Antimicrobial compounds from seaweedsassociated bacteria and fungi
Ravindra Pal Singh, Puja Kumari & C. R. K. Reddy
Applied Microbiology and Biotechnology ISSN 0175-7598 Volume 99 Number 4 Appl Microbiol Biotechnol (2015) 99:1571-1586 DOI 10.1007/s00253-014-6334-y
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Author's personal copy Appl Microbiol Biotechnol (2015) 99:1571–1586 DOI 10.1007/s00253-014-6334-y
MINI-REVIEW
Antimicrobial compounds from seaweeds-associated bacteria and fungi Ravindra Pal Singh & Puja Kumari & C. R. K. Reddy
Received: 27 August 2014 / Revised: 14 December 2014 / Accepted: 15 December 2014 / Published online: 31 December 2014 # Springer-Verlag Berlin Heidelberg 2014
Abstract In recent decade, seaweeds-associated microbial communities have been significantly evaluated for functional and chemical analyses. Such analyses let to conclude that seaweeds-associated microbial communities are highly diverse and rich sources of bioactive compounds of exceptional molecular structure. Extracting bioactive compounds from seaweedassociated microbial communities have been recently increased due to their broad-spectrum antimicrobial activities including antibacterial, antifungal, antiviral, anti-settlement, antiprotozoan, antiparasitic, and antitumor. These allelochemicals not only provide protection to host from other surrounding pelagic microorganisms, but also ensure their association with the host. Antimicrobial compounds from marine sources are promising and priority targets of biotechnological and pharmaceutical applications. This review describes the bioactive metabolites reported from seaweed-associated bacterial and fungal communities and illustrates their bioactivities. Biotechnological application of metagenomic approach for identifying novel bioactive metabolites is also dealt, in view of their future development as a strong R. P. Singh (*) : P. Kumari : C. R. K. Reddy (*) Discipline of Marine Biotechnology and Ecology, CSIR—Central Salt and Marine Chemicals Research Institute, Bhavnagar 364002, Gujarat, India e-mail:
[email protected] e-mail:
[email protected] R. P. Singh Laboratory of Microbial Technology, Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan P. Kumari Institute of Plant Sciences, Agricultural Research Organization (ARO), Volcani Center, PO Box 6, Bet Dagan 50250, Israel C. R. K. Reddy Academy of Scientific and Innovative Research (AcSIR), New Delhi, India
tool to discover novel drug targets from seaweed-associated microbial communities. Keywords Biotechnological application . Seaweed . Antibacterial . Antifungal . Antifouling . Bioactive compounds . Metagenomics
Introduction Marine waters comprise a high diversity of microbial life, predominantly including bacteria, fungi, viruses, spores, and actinomycetes (Engel et al. 2002; Harder 2009). These organisms also settle on marine animals and plants, besides occurring in sea surface, and form unique associations with their hosts (Lafi et al. 2005; Webster et al. 2008; Singh and Reddy 2014). Associated microorganisms utilize nutrients (e.g., carbon) source produced by their host and in return protect them from harmful entities in surrounding by secretion of certain biological active molecules called “bioactives” (Armstrong et al. 2001; Jiang et al. 2001; Jamal et al. 2006; Lane and Kubanek 2008). Seaweeds are part of highly productive ecosystems and are habitats of numerous bioactive compounds producing microorganisms. Bioactive compounds obtained from associated microorganisms are known for broad range of biological effects such as antimicrobial, antisettlement, antiprotozoan, antiparasitic, and antitumors (Egan et al. 2001, 2008; Penesyan et al. 2011; Lee et al. 2013). For example, Egan et al. (2001; 2002) identified a number of Pseudoalteromonas strains from surface of Ulva australis that exhibited antisettlement activity against invertebrate larvae and algal spores as well as antibacterial and antifungal activities. Mostly, bioactive compounds producing microorganisms are evolved through high competitive environment due to nutrient and space limitation on their host surface that led them to produce
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allelochemicals capable of preventing secondary colonisation (Egan et al. 2001, 2008). These bioactives are secondary metabolites and have exceptional molecular structure as compared to those produced by terrestrial microorganisms (Fenical and Jensen 1991; Fenical 1993; Clardy et al. 2006; Penesyan et al. 2009, 2010). The bioactivities of such secondary metabolites indicate that they possess pharmaceuticals, industrial, agricultural, and biotechnological applications (Armstrong et al. 2001; Penesyan et al. 2011). Recently, seaweed-associated microorganisms have significantly been investigated for analysis of microbial communities and identification of their bioactivities (Molinski et al. 2009; Penesyan et al. 2009, 2011, 2013a, b; Burke et al. 2011; Bondoso et al. 2013; Goecke et al. 2013; Hollants et al. 2013; Tebben et al. 2014). Nevertheless, most of the studies have been carried out to understand bioactivities produced mostly from bacterial and fungal sources associated with seaweeds as compared to other microorganisms, which remains mostly unexplored (Egan et al. 2008). Therefore, this review discusses the significance of associated bacteria and fungi for targeting isolation of bioactive molecules and exploring metagenomic approach for searching broad range bioactives (Fig. 1).
Bioactivities of seaweeds-associated bacteria Among other microbial communities living on the seaweed surface, bacteria are ubiquitous and present as either extracellular or in the cytosol of living host cells and determine the different stages of life span of Ulva and Gracilaria species (Holmström et al. 2002; Tait et al. 2009; Burke et al. 2011; Singh et al. 2011a, b). Several studies have been demonstrated that seaweed-associated bacteria play crucial roles in
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determining the normal morphology, growth, and development of the host (Nakanishi et al. 1999; Matsuo et al. 2003; Marshall et al. 2006; Singh and Reddy 2014). For instance, Matsuo et al. (2005) found a thallusin bioactive molecule, which was responsible for morphogenesis in Monostroma oxyspermum. As above mentioned, seaweeds can also be considered as rich sources for microbial nutrients that ultimately leads to high competition between different microbial communities (Burgess et al. 1999; Armstrong et al. 2001; Penesyan et al. 2009). Such circumstances force bacteria to evolve in such a way that they can produce certain antimicrobial compounds to sustain competition from other microbes. This selection further revealed that associated bacterial communities might produce novel drugs as compared to other surface dwelling microbes to ensure their position on host. Thus, it has been found that these associated bacteria produce various bioactive compounds including haliangicin, violacein, pelagiomicin A, korormicin, macrolactines, and chlorophyll d which exhibit the antifungal, antiprotozoal, antisettlement, antibiotic activity against gram-negative bacteria, gram-positive, and photosynthetic activity, respectively (Imamura et al. 1997; Yoshikawa et al. 1997, 1999; Gerard et al. 1997; Fudou et al. 2001; Murakami et al. 2004; Matz et al. 2008; Goecke et al. 2010). Bioactive compounds extracted from seaweed-associated microorganisms have dramatically increased in past decades with nearly 600 % from the last century (Gulder and Moore 2009; Waters et al. 2010). Such increasing evidences are proved that marine-associated bacteria produce novel valuable compounds having the higher chances for development of pharmaceutical drugs (Debnath et al. 2007; IsmailBen Ali et al. 2012; Tebben et al. 2014). For instance, Lemos et al. (1985) demonstrated that 17 % of 224 isolates displayed antibacterial activity affiliated with five species of green and brown algae. Kanagasabhapathy et al. (2006) reported that
Fig. 1 Graphical represent of green seaweed, existing of bacterial and fungal communities on their surface and structure of bioactive compounds
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20 % of epiphytic bacterial strains associated with nine species of brown alga exhibit antibiotic activities. Similarly, Penesyan et al. (2009) isolated 325 bacterial isolates from Delisea pulchra and U. australis and 12 % of them showed antibacterial activities. Moreover, high proportions of antimicrobial producing bacterial isolates have also been reported. Kanagasabhapathy et al. (2008) reported that 33 % of epiphytic bacterial strains associated with nine species of red alga exhibit antibiotic activities. Burgess et al. (1999) found 35 % of the surface-associated bacteria having antibacterial activities. Wiese et al. (2009) studied the antibiotic active bacteria associated with brown algae Saccharina latissima and found that 50 % associated bacterial strains inhibited the growth of either gram-negative or gram-positive bacteria or yeast. Ma et al. (2009) isolated 192 bacterial strains and out of them 63 strains (32.81 %) revealed antisettlement effect against Ulva lactuca as well as anti-larval activity. JanakiDevi et al. (2013) isolated 126 bacteria from five different seaweeds (Gracillaria corticata, Geledium pussilum, Hypnea musiformis, Padina gymnosphora, and Valoniopsis pachynema) which showed antibacterial activity (2.6 to 16 mm inhibitory zone) against Escherichia coli, Staphylococcus sp., Klebshilla pneumonia, Pseudomonas aeroginosa, Micrococcus sp., Salmonells sp., Vibrio cholera, Shigella dysenteriae, and Serratia sp. Recent studies revealed that bacterial communities associated with seaweeds are significantly different from marine waters (Burke et al. 2011; Tujula et al. 2010; Lachnit et al. 2011). The seaweed surface is predominately occupied by diverse groups of bacterial communities belonging to Alphaproteobacteria, Gammaproteobacteria, Firmicutes, Actinobacteria, Bacteroidetes, and Planctomycetes (Burke et al. 2011; Tujula et al. 2010; Longford et al. 2007; Bondoso et al. 2013; Hollants et al. 2013). Therefore, antimicrobial compounds extracted from associated bacterial communities are belonged to various genera such as Pseudomonas, Pseudoalteromonas, Stenotrophomonas, Vibrio, Alteromonas, Shewanella, Streptomyces, and Bacillus species (Wiese et al. 2009). Burgess et al. (2003) identified most of the Bacillus strains associated with antifouling activities. Epiphytic Vibrio species present on green alga Ulva reticulata significantly inhibited settlement and metamorphosis of polychaete larvae and may attribute to the host alga protection against further fouling (Dobretsov and Qian 2002). Similarly, epiphytic Pseudoalteromonas tunicata and Roseobacter gallaeciensis are found in association with green alga U. australis and produce a range of extracellular inhibitory compounds against marine fungi, bacteria, invertebrate larvae, and algal spores (Holmström et al. 2002; Rao et al. 2007). In contrast, three epiphytic strains of Pseudoalteromonas sp. isolated from seaweeds exhibited autoinhibitory activities (Holmström et al. 2002). Autoinhibitory activity might serve to prevent the predominance of any single specific bacterial species and assist in maintaining the bacterial diversity on the specific host. Some gram-positive and gram-negative bacteria produce autolysin
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compounds, which hydrolyse the peptidoglycan of the bacterial cell wall and lead to the release of intracellular substances (Li et al. 1998). Kumar et al. (2011) isolated ten residential bacteria from tropical green alga U. lactuca and found that most of the epiphytic isolates showed antibacterial and antidiatom activity against other resident bacteria and a diatom, Cylindrotheca fusiformis, respectively. Furthermore, their results indicated that Pseudoalteromonas genus has a broad-spectrum activity whereas Bacillus, Vibrio, and Shewanella mostly revealed antidiatom activity. The antibacterial compounds produced by seaweedassociated Alteromonas aurantia (Gauthier and Breittmayer 1979), Alteromonas rubra (Gauthier 1979), and Alteromonas luteoviolacea (Gauthier 1976) were composed of high molecular mass molecules, suggested to inhibit bacterial respiration and reduce further fouling. Therefore, Silva-Aciares and Riquelme (2008) studied the effect of biofilms and extracellular products (EP) of the indigenous bacterium Alteromonas sp. strain Ni1LEM (associated with red macroalga, Rhodymenia sp.) on zoospores germination and settlement of green alga U. lactuca. They also found a high molecular weight protein, 3500 Da that was thermostable, hydrophilic in nature with high antifouling potential. The present study is hereby summarizing the bioactivities of seaweed-associated bacterial genera which are highly promising candidates for pharmaceutical applications. Pseudoalteromonas Those species of genus Pseudoalteromonas that are present in association with marine macroalgae produce extracellular compounds that inhibits or control fouling of other species on the host surface (Holmstrom and Kjelleberg 1999). These activities related to the production of some microbial compounds. For example, two important diketopiperazines, cyclo-(L-prolyl-Lglycine) and cyclo-(L-phenylalanyl-4R-hydroxy-L-proline), and 2,4-dibromo-6-chlorophenol were extracted from Padina australis associated with marine bacteria Pseudoalteromonas luteoviolacea (Jiang et al. 2001). Both diketopiperazines stimulated antibiotic production in this strain whereas 2,4-dibromo6-chlorophenol showed antibacterial activity against cystic fibrosis associated with pathogen Burkholderia cepacia and methicillin resistant Staphylococcus aureus (MRSA). The novel korormicin drug (Fig. 2a) originally was obtained from Halimeda sp. associated with bacterium, Pseudoalteromonas sp. F-420 and was significantly investigated for its biological activity against gram-negative bacteria (Yoshikawa et al. 1997). Further study of Yoshikawa et al. (2003) identified five derivatives of original compound korormicin from Pseudoalteromonas sp. F-420 which showed antibacterial activity against marine Vibrio spp., Salinivibrio costicola and Pseudoalteromonas haloplanktis, but no activity against terrestrial bacterium. Interestingly, the respiratory chain of marine bacterium Vibrio alginolyticus and halophilic
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Fig. 2 Some representatives of structurally potential bioactive compounds obtained from seaweed associated bacteria. a Base structure of korormicin; b tetrodotoxin, c 2,4diacetylphloroglucinol, d haliangicin, and e tropodithietic acid
Vibrio costicolus has a unique Na+ -dependent NADHquinone reductase that functions as a primary Na+ pump and is required for its maximum activity (Unemoto et al. 1977; Hayashi et al. 2002). The Na+-translocating NADH-quinone reductase (NQR) of V. alginolyticus is composed of six structural genes, namely nqrA, nqrB, nqrC, nqrD, nqrE, and nqrF (Beattie et al. 1994; Hayashi et al. 1994; 1995). It has been found that korormicin specifically inhibited the NQR complex of these marine halophilic Vibrio species (Nakayama et al. 1999). Later, homology search of the nqr operon revealed that the Na+-pumping NQR complex is widely distributed among gram-negative pathogenic bacteria (Hayashi et al. 2002). This drug is potentially suggested for pharmaceutical application. Recently, Tebben et al. (2014) identified 13 natural products from Pseudoalteromonas strain J010, which were isolated from surface of the crustose coralline alga Neogoniolithon fosliei. Among them, a new bromopyrrole, 4-((3,4,5-tribromo1H-pyrrol-2-yl) methyl)phenol and five new korormicins G– K were obtained which exhibited antibacterial activity. Interestingly, this strain also produced a coral larval metamorphosis inducer compound, tetrabromopyrrole which had a broad-spectrum activity against the tested bacteria, fungi, and protozoan (Tebben et al. 2011, 2014). Two more novel compounds (violacein and YP1) were obtained from U. australis associated with P. tunicata (Franks et al. 2006; Matz et al. 2008). Violacein (an alkaloid) producing P. tunicata and P. ulvae showed antiprotozoal activity against amoeba Acanthamoeba castellanii at nanomolar concentration (Matz et al. 2008). It also demonstrated that violacein induces apoptosis-like cell death program in protozoan predators. It has been observed that violacein produced by Chromobacterium violaceum induces apoptosis in mammalian cell lines (Ferreira et al. 2004; Kodach et al. 2006). Therefore, it could be a novel therapeutic agent to treat cancerous cells (Matz et al. 2008). Recently, Subramaniam et al.
(2014) demonstrated that synergistic administration of violacein with available antibiotics such as azithromycin, gentamicin, kanamycin, and cefadroxil could increase its potential. It was observed that violacein-azithromycin and violacein-kanamycin combination exhibited significant fractional inhibitory concentration indices (0.3) against Salmonella typhi as compared to violacein alone (5.7 μg/ mL). Similarly, violacein-gentamicin and violaceincefadroxil combination had MIC of 1.0 μg/mL against S. aureus as compared to violacein alone (5.7 μg/mL). P. tunicata produces YP1 (a tambjamine class of compound), a yellow pigment compound that contains a 2,2-bipyrrolering with an unsaturated 12 carbon alkyl chain (Franks et al. 2005) and is reported for its antifungal activity (Franks et al. 2006). Pseudomonas The genus Pseudomonas species are also known to produce several antimicrobial compounds by which they protect host alga from harmful microorganisms. An important drug tetrodotoxin (TTX, a potent neurotoxin, Fig. 2b) initially isolated from toxic pufferfish (Yokoo 1950) was also obtained from Pseudomonas sp. associated with Jania sp. (Yasumoto et al. 1986), and the structure was elucidated in 1964 (Tsuda et al. 1964; Woodward 1964; Goto et al. 1965). TTX inhibits nerve and muscle conduction via binding to the voltage-gated Na+ channels in nerve cell membranes and thereby preventing action potential generation and propagation (Lee and Ruben 2008), ultimately leading to death of the organism. Magnesidin, a novel magnesium-containing antibiotic, was obtained from novel bacterium Pseudomonas magnesiorubra associated with Caulerpa peltata (Gandhi et al. 1973). It is a complex structure of the magnesium salts of two tetramic acids, l-acetyl-3-n-hexanoyl-5-ethylidene tetramic acid (n= 4) and l-acetyl-3-n-octanoyl-5-ethylidene tetramic acid (n=
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6). It has a strong antibacterial activity against Staphylococcus and Bacillus spp. (Gandhi et al. 1973). Another compound 2, 4-diacetylphloroglucinol, DAPG (Fig. 2c) was obtained from novel bacterium Pseudomonas sp. strain AMSA. This strain was originally isolated from a red alga Ceratodyction spongiosum (Isnansetyo et al. 2001) and strongly inhibited growth of the Methicillin-resistant S. aureus (MRSA). Further study of Kamei and Isnansetyo (2003) found that DAPG inhibited growth of MRSA at 1 mg/L and V. parahaemolyticus at 24 mg/L. It was also observed that DAPG stables at temperature ranging from 35 to 70 °C and pH at 2 to 7. Four important compounds massetolides A, B, C, and D were extracted from EtOAc-fraction of the Pseudomonas sp. associated with an unidentified red alga (Gerard et al. 1997). These novel cyclic depsipeptides inhibited growth of Mycobacterium tuberculosis and M. avium-intracellulare (Gerard et al. 1997). In another study, two new peptides cyclo-[phenylalanyl-prolyl-leucylprolyl] and cyclo-[isoleucyl-prolyl-leucyl-alanyl] were obtained from a Pseudomonas sp. associated with Japanese seaweed Diginea sp. (Rungprom et al. 2008). These peptides were found to inhibit growth of S. aureus, Micrococcus luteus, Bacillus subtilis, E. coli, and Vibrio anguillarum. Massetolide A obtained from Pseudomonas fluorescens was found as a biological agent to control the growth of late blight producing fungal pathogens Phytophthora infestans (Tran et al. 2007). Recently, Ravisankar et al. (2013) identified an alkaloid from Pseudomonas sp. associated with Padina tetrastromatica. This compound inhibited growth of human pathogenic bacteria, K. pneumoniae and Pseudomonas aeruginosa with 15 and 10 mm inhibitory zone, respectively, at a concentration of 300 μg. Bacillus Among firmicutes group, Bacillus species are dominantly present on the surface of diverse seaweeds (Lachnit et al. 2009; Tujula et al. 2010; Burke et al. 2011; Lachnit et al. 2011). These species have been reported for antibacterial and antifungal activities (Burgess et al. 2003; Kanagasabhapathy et al. 2006; Penesyan et al. 2010). An important antibacterial protein (30.7 kDa) was obtained from Bacillus licheniformis associated with Fucus serratus. This novel protein showed activity against MRSA, vancomycin-resistant enterococci, and Listeria monocytogenes (Jamal et al. 2006). A series of novel macrolactin G, H, I, J, K, L, and M was extracted from Bacillus sp. PP19-H3 associated with seaweed, Schizymenia dubyi (Nagao et al. 2001). It was also found to produce macrolactines A and F that were previously extracted from Actinomadura sp. (Kim et al. 1997) and Bacillus sp. (Jaruchoktaweechai et al. 2000), respectively. Among all macrolactines, macrolactin A had strong antibacterial activity
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against S. aureus IFO 12732 and B. subtilis IFO 3134 (Nagao et al. 2001), while none of them inhibited growth of the E. coli IFO 3301 and S. costicola (ATCC33508). However, recently reported novel macrolactin S (obtained from a marine Bacillus sp.) and macrolactin W (obtained from a marine Bacillus sp. 09ID194) exhibited broad-spectrum antibacterial activity against gram-positive and gram-negative pathogenic bacteria (Lu et al. 2008; Mondol et al. 2011). Additionally, a novel polyketide family member 7-O-methyl-5′-hydroxy-3′heptenoate-macrolactin was also obtained from seaweed, Anthophycus longifolius associated with B. subtilis MTCC 10403 strain (Chakraborty et al. 2014). The particular compound showed 12–22 mm inhibitory zone against different species of Vibrio sp. Interestingly, a bacteriocin (lichenicidin, a class of lentibiotics) was also confirmed from seaweeds-associated B. licheniformias and also suggested that seaweed-associated Bacillus spp. could be source for novel bacteriocin (Prieto et al. 2012). Subsequently, another bacteriocin (approximately 8 kDa molecular weight) was partially characterized from seaweed-associated Staphylococcus haemolyticus MSM and exhibited strong antibacterial activity against human pathogenic bacteria (Suresh et al. 2014).
Bioactivities of some other seaweed-associated bacterial groups Some other bacterial groups also produce potential bioactive drugs. For instance, a halophilic gram-negative bacterium Pelagiobacter variabilis isolated from a brown alga Pocockiella variegata (Imamura et al. 1997) produce an important drug pelagiomicin A, a phenazine antibiotic. This compound exhibits activity against gram-positive and gramnegative bacteria and has antitumor activity against HeLa (IC50 0.04 μg/mL), BALB3T3 (IC50 0.02 μg/mL), and BALB3T3/H-ras (IC50 0.07 μg/mL) in vivo. An antifungal drug, haliangicin (Fig. 2d), was obtained from marine seaweed (undefined) associated with bacterium, Haliangium luteum (Fudou et al. 2001). It has potent activity against filamentous fungi comparable to antifungal known drugs amphotericin B and nystatin and other drugs belonging to β-methoxyacrylate type compounds (Fudou et al. 2001). It is suggested that haliangicin blocked the electron flow within cytochrome b-cl part of the electron transport chain of mitochondria. Haliangicin was also reported to possess cytotoxicity against mouse P388 cell lines (IC50 0.21 μM) (Fudou et al. 2001). An epiphytic bacterium, Pseudovibrio sp. D323 isolated from D. pulchra produced antibacterial compound tropodithietic acid (TDA) (Fig. 2e). TDA has a broadspectrum effect against large range of bacteria belonging to
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Proteobacteria, Actinobacteria, Firm icutes , and Bacteroidetes (Penesyan et al. 2011). Interestingly, it was found that only TDA producing bacterial strains are resistant to this compound while non-TDA producing strains were sensitive (Bruhn et al. 2007; Penesyan et al. 2011). Although, it is suggested that TDA producing bacterial strains may possess resistance mechanism to prevent auto-inhibition but this mechanism is still not well defined. Latest, Braña et al. (2014) identified several bioactive compounds from seaweed-associated (also found with coral) Streptomyces strains, Streptomyces cyaneofuscatus M-27 and Staphylococcus carnosus M-40. These compounds are daunomycin (anticancer), cosmomycin B (antitumor), galtamycin B (antitumor), maltophilins (antifungal), and lobophorins (anti-inflammatory, anti-BCG and antituberculosis) and are known to display several biological activities. Recently, Suvega and Kumar (2014) isolated 673 isolates from different seaweeds, sediments, and soil. Maximum bacterial isolates were obtained from different seaweeds and 40.2 % isolates belonged to the species of Bacillus sp. Interestingly, maximum bioactive compounds producing bacterial isolates (epibiotics, 39.54 % and endobiotics, 40.74 %) were obtained from the surface of seaweeds as compared to the seawater (8.61 %) and the sediments (11.11 %). These isolates produced antimicrobial compounds and were active against plant pathogens (Xanthomonas axonopodis pv. citri, X. oryzaepv. oryzae and Ustilaginoidea virens). Proteins present in the extracellular components of these bacterial isolates were highly active at pH 7.0 and showed antibacterial activity up to 40 °C and antifungal property up to 60 °C. Whereas nonpolar lipophilic compounds extracted from these active bacteria only displayed antifungal activity (Suvega and Kumar 2014). Kanagasabhapathy et al. (2009) screened 96 bacterial isolates obtained from a brown alga Colpomenia sinuosa for identification of quorum quenching against Serratia rubidaea JCM 14263, as an indicator organism which controls the production of red pigment, prodigiosin, and is mediated by acylhomoserine lactone (quorum sensing molecule). Out of them, only 12 % of the isolates inhibited the production of prodigiosin. The phylogenetic analysis revealed that those isolates belonged to Bacillaceae, Pseudomonadaceae, and Pseudoalteromonadaceae. Cho and Kim (2012) isolated one actinomyces (Streptomyces cinnabarinus) and bacteria (Alteromonas sp.) from rhizospheric part of the seaweed and observed that in presence of Alteromonas sp., S. cinnabarinus increased production of lobocompactol which showed significant antifouling activity against Ulva pertusa and the diatom Navicula annexa with 0.18 and 0.43 μg/mL, respectively. It also showed antifouling activity against bacteria. VillarrealGómez et al. (2010) isolated 35 bacterial strains from different seaweeds and among them Cc51 (associated with Centroceras clavulatum), Sm36 (associated with Sargassum muticum), and
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Eb46 strains (associated with Endarachne binghamiae) showed anticancer activity, with IC50 values of 6.492, 5.531, and 2.843 μg/mL, respectively.
Bioactivities of seaweeds-associated fungi Seaweeds represent second largest, source of diverse assemblage of marine fungi (Bugni and Ireland 2004; Schulz et al. 2008; Loque et al. 2010; Suryanarayanan et al. 2010; Godinho et al. 2013). Seaweed-associated fungi mostly include parasites, saprobes, or asymptomatic fungal endosymbionts (Bugni and Ireland 2004; Zuccaro et al. 2008; Loque et al. 2010; Suryanarayanan et al. 2010). A number of seaweeds encompassing genera of Adenocystis, Ascophyllum, Desmarestia, Dictyota, Fucus, Lobophora, Padina, Phaeurus, Sargassum, Stocheospermum, and Turbinaria (belonging to Phaeophyceae), Gelidiella, Gracilaria, Grateloupia, Halymenia, Palmaria, Plocamium, Portieria, Pyropia (belonging to Rhodophyceae) and Acrosiphonia, Caulerpa, Halimeda, Monostroma, and Ulva (belonging to Chlorophyceae) have been extensively studied worldwide for their fungal associations (Table 1). Most of the studies revealed that ascomycetes and anarmorphic fungi were the dominant fungal endosymbionts (Schulz et al. 2008; Zuccaro et al. 2008; Loque et al. 2010; Suryanarayanan et al. 2010; Suryanarayanan 2012; Suryanarayanan et al. 2012; Flewelling et al. 2013; Godinho et al. 2013; Furbino et al. 2014). Red and brown seaweeds harbored greater fungal species diversity as compared to green seaweeds (Suryanarayanan et al. 2010). It has been proposed that short life cycle of some of the green seaweeds and characteristically slow growth of the endosymbionts could together be responsible for low fungal diversity in green seaweeds (Zuccaro and Mitchell 2005). Members of genera Acremonium, Alternaria, Arthrinium, Aspergillus, Cladosporium, Fusarium, Geomyces, Penicillium, and Phoma (Zuccaro et al. 2003; 2008; Loque et al. 2010; Suryanarayanan et al. 2010; Flewelling et al. 2013; Godinho et al. 2013; Furbino et al. 2014) were the most common fungal endosymbionts in different seaweeds (Table 1). Like bacteria, seaweed-associated fungi also produce numerous novel bioactive metabolites that exhibit anticancer, antibacterial, antiplasmodial, anti-inflammatory, nematicidal, antiviral, and antiangiogenic activities (Suryanarayanan et al. 2010; Oliveira et al. 2012; Flewelling et al. 2013; Godinho et al. 2013; Lee et al. 2013; Furbino et al. 2014; Suja et al. 2014). Suryanarayanan and coworkers (Suryanarayanan et al. 2010; Suryanarayanan 2012) demonstrated that fungal isolates from green, red, and brown seaweeds produce antialgal, antifungal, and insecticidal metabolites which may help in deterring colonization of algal thalli by other microbes thereby reducing competition and in warding off herbivores.
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List of fungi isolated from seaweeds
Seaweed host
Seaweed-associated fungi
Acrosiphonia arcta
Geomyces sp., Metschnikowia australis, Penicillium sp., Candida sake, Cladosporium sp., Godinho et al. 2013 Cladosporium tenuissimum, Debaryomyces hansenii, Mortierella sp., Phoma sp., Thelebolus globosus Aspergillus spp., Aureobasidium pullulans, Chaetomium spp., Cladosporium spp., Fusarium Suryanarayanan et al. 2010 spp., Mucor sp., Penicillium spp., Phoma sp., Pyrenochaeta sp. Aspergillus spp., Chaetomium spp., Curvularia spp., Paecilomyces spp., Penicillium spp. Suryanarayanan et al. 2010
Caulerpa racemosa
Caulerpa scalpelliformis Caulerpa Aspergillus spp., Chaetomium spp., Cladosporium spp., Fusarium spp., Myrothecium sp., sertularioides Penicillium spp., Phialophora sp. 1 1 Desmarestia [Metschnikowia australis, Penicillium sp.], 2[Geomyces pannorum menziesii, 2 D. anceps Halimeda macroloba Aspergillus spp., Chaetomium spp., Paecilomyces spp., Penicillium spp., Trichoderma sp. Monostroma hariotii
Ulva lactuca
Ulva fasciata Ulva intestinalis
References
Suryanarayanan et al. 2010 1
Godinho et al. 2013, 2Loque et al. 2010
Suryanarayanan et al. 2010
1
1
[Geomyces destructans, Penicillium sp., Meyerozyma guilliermondii, Cryptococcus cf. Godinho et al. 2013, 2Furbino laurentii, Cordycipitaceae sp., Helotiales sp., Hyaloscyphaceae sp., Rhodotorula et al. 2014 mucilaginosa], 2[Penicillium steckii, Penicillium sp., Aspergillus sp., Aspergillus tabacinus, Cladosporium sp., Penicillium citrinum, Penicillium crustosum Thom, Penicillium crustosum, Metschnikowia australis, Guehomyces pullulans, Cryptococcus albidosimilis, Cryptococcus adeliensis, Rhodotorula larynges, Rhodotorulaminuta, Rhodotorula mucilaginosa, Phoma sp., Pseudogymnoascus sp., Cystofilobasidium firmominiatum, Meyerozyma guilliermondii] 1 [Aspergillus spp., Chaetomium spp., Cladosporium spp., Nigrospora sp., Penicillium spp.], 1Suryanarayanan et al. 2010, 2 2 [Leotiomyceta sp., Eurotium sp., Stilbella fimetaria, Penicillium sp., Pseudeurotium Flewelling et al. 2013, bakeri] Aspergillus spp., Chaetomium spp., Curvularia spp., Paecilomyces spp. Suryanarayanan et al. 2010 1
1
Gelidiella acerosa
[Penicillium sp., Penicillium discolor, Antarctomyce spsychrotrophicus, Cryptococcus victoriae, Engyodontium sp., Geomycesluteus, Helotiales sp., Mycoarthris cf. corallines, Penicillium sp., Thelebolus globosus], 2[Bionectria ochroleuca, Leptosphaeria sp., Penicillium sp., Cordyceps sp.] Alternaria spp., Aspergillus sp., Penicillium spp., Phoma sp.
Gracilaria spp.
Aphanocladium sp., Aspergillus sp., Monilia sp., Paecilomyces spp.
Suryanarayanan et al. 2010
Grateloupia lithophila Halymenia spp.
Aspergillus sp., Cladosporium spp.
Suryanarayanan et al. 2010
Aspergillus sp., Cladosporium spp., Drechslera spp., Emericella nidulans, Paecilomyces spp., Penicillium spp., Phoma sp. Palmaria decipiens 1[Penicillium sp., Geomyces sp., Acremonium sp., Fusarium sp., Yamadazyma mexicana, Aspergillus sp., Chaetomium sp., Penicillium spinulosum] 2[Cryptococcus carnescens] Seaweed host Seaweed associated Fungi Portieria hornemanii Aspergillus sp., Cladosporium spp., Memnoniella sp., Penicillium spp., Phomopsis sp., Trimmatostroma sp. Pyropia endiviifolia Cladophora maronum, Penicillium spp., Pseudogymnoascus spp., T. globosus, Aspergillus sp., Aspergillus protuberus, Antarctomyces psychrotrophicus, Cladosporium lignicola, Mortierella antarctica, Oidiodendron truncatum, Metschnikowia australis, Dipodascus australiensis, Meyerozyma guilliermondii, Verticillum sp., Lecanicillium sp. 1 Adenocystis spp. [Penicillium spp., Aspergillus conicus, Geomyces sp., Debaryomyces hansenii, Meyerozyma caribbica] 2[Antarctomyces psychrotrophicus, Geomyces pannorum, Oidiodendron sp., Penicillium sp., Phaeosphaeria herpotrichoides, Algicolous fungi] Ascophyllum Aspergillus fumigatus, Lichtheimia corymbifera, Cladosporium sp., Dendryphiella salina nodosum Dictyota dichotoma Aspergillus spp., Trichoderma sp.
Suryanarayanan et al. 2010
Suryanarayanan et al. 2010 Godinho et al. 2013 References Suryanarayanan et al. 2010 Furbino et al. 2014
1
Godinho et al. 2013, 2Loque et al. 2010
Flewelling et al. 2013 Suryanarayanan et al. 2010
Fucus vesiculosus
[Lindra, Lulworthia, Engyodontium, Sigmoidea/ Corollospora complex, and Emericellopsis/ Zuccaro et al. 2008, 2Flewelling Acremonium-like ribotypes], 2[Aspergillus fumigatus, Coniothyrium sp., Penicillium sp., et al. 2013 Coniothyrium sp.] Aspergillus fumigatus, Coniothyrium sp., Penicillium sp., Alternaria sp. Flewelling et al. 2013
Fucus spiralis
Penicillium sp.
Fucus serratus
1
Godinho et al. 2013, 2 Flewelling et al. 2013
1
Flewelling et al. 2013
Lobophora variegata Aspergillus spp., Chaetomium spp., Emericella nidulans, Nigrospora sp.
Suryanarayanan et al. 2010
Padina tetrastomatica
Suryanarayanan et al. 2010
Acremoniella sp., Aspergillus spp., Chaetomium spp., Monodictys sp., Paecilomyces spp., Penicillium spp.
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Table 1 (continued) Seaweed host
Seaweed-associated fungi
References
Padina gymnospora
Aspergillus spp., Chaetomium spp., Cladosporium spp., Phoma sp., Trichoderma sp.
Suryanarayanan et al. 2010
Phaeurus antarcticus Penicillium sp., Geomyces sp., Aspergillusterreus, Eurotium herbariorum, Eurotium repens, Godinho et al. 2013 Penicillium steckii Plocamium Metschnikowia sp., Acremonium sp., Cladosporium sp., Penicillium biourgeianum Flewelling et al. 2013 cartilagineum 1 Sargassum sp. [Corollospora sp.], 2[Alternaria spp., Aspergillus spp., Colletotrichum sp., Drechslera spp., 1Schulz et al. 2008, 2 Suryanarayanan et al. 2010 Helicosporium sp., Nigrospora sp., Taeniolella sp., Varicosporium sp.] Sargassum wightii Stocheospermum marginatum Turbinaria spp.
Aspergillus spp., Cladosporium spp., Emericella nidulans, Nigrospora sp., Oidiodendron sp., Suryanarayanan et al. 2010 Paecilomyces spp. Alternaria spp., Aspergillus spp., Chaetomium spp., Emericella nidulans, Nigrospora sp. Suryanarayanan et al. 2010 Aspergillus spp., Chaetomium spp., Cladosporium spp., Colletotrichum sp., Curvularia spp., Suryanarayanan et al. 2010 Drechslera spp., Emericella nidulans, Fusarium spp., Monodictys sp., Nigrospora sp., Paecilomyces spp., Phaeotrichoconis sp., Phialophora sp., Phoma sp.
Superscript numbers represent their respective references
Additionally, it has been found that endophytes produce antioxidant chemicals that protect their host plants from diseases, drought, and heavy metal toxicity by increasing tolerance of the host to oxidative stress (White and Torres 2010). Flewelling et al. (2013) demonstrated that the mycelial and broth extracts from endophytic fungal isolates isolated from different seaweeds showed potent bioactivities wherein, 15 extracts had antimicrobial activities with >80 % inhibition against S. aureus, P. aeruginosa, and Candida albicans. Also, seven extracts obtained from Microdochium sp. (isolated from Porphyra sp.), Sterile Pigmented II and III (isolated from Ulva intestinalis), Penicillium sp. V and VI (isolated from Fucus spiralis) had larvicidal activities with a LC50 < 100 μg/mL. Mathan et al. (2013) screened 19 seaweed endophytic fungal strains for their bioactivity against human and fish pathogenic bacteria such as E. coli, S. aureus, V. parahaemolyticus, Klebsiella oxycota, V. cholera, and fish bacterial pathogens, Aeromonas hydrophila, Enterobacter aerogens, Flavobacterium sp., Micrococcus sp., and P. fluorescens of which six strains showed >10 mm of zone of inhibition. These authors proposed that antibacterial activity might be due to the presence of bioactive metabolites produced by the seaweed endophytic fungi. Recently, Furbino et al. (2014) collected 239 fungal isolates from 390 thalli of the endemic Antarctic macroalgae, Monostroma hariotii and Pyropia endiviifolia, and found that extracts of these endemic and cold-adapted fungi displayed biological activities. Only six fungal taxa potentially showed antifungal activity with 61–96 % of inhibition. The extracts of Pseudogymnoascus sp., Guehomyces pullulans, and Metschnikowia australis showed selective antifungal activities against C. albicans, Candida krusei, and Cladosporium sphaerospermum. The extract of Dipodascus australiensis inhibited selectively the growth of C. albicans; G. pullulans, M. australis, and Pseudogymanoascus sp. 1 were selective
against C. krusei. Pseudogymnnoascus sp. 2 displayed 95 % antifungal activity against the target C. sphaerospermum, which was approximately the same value of the control drug benomyl (94.5 % of inhibition). The extract of Penicillium steckii inhibited 96 % of yellow fever virus, which was much better than the control interferon alpha (IFN-α) (68 %) (Furbino et al. 2014). Metabolites produced from seaweed-associated fungi include ß aromatic polyketides, alkaloids, sesquiterpenes, and terpenes (Osterhage et al. 2000, 2002; Bugni and Ireland 2004; Gao et al. 2011a, b, c; Oliveira et al. 2012). In general, metabolites derived from fungi associated with green seaweeds (such as Coniothyrium cereal, Chaetomium sp., and Penicillium sp.) are reported to contain bicyclical structures with oxygenations or even aromatic moieties and showed cytotoxicity, antiprotozoal, antimicrobial activities, and protection from DNA damage (Gamal-Eldeen et al. 2009; Zhu et al. 2009; Elsebai et al. 2010). Metabolites derived from fungi associated with brown seaweeds (such as Aspergillus niger and Aspergillus ochraceus) demonstrated a greater structural diversity and included compounds with naphto- and pyrone derivatives exhibiting antifungal and antioxidant activities (Zhang et al. 2007; 2010), antioxidant benzodiazepine derivatives (Cui et al. 2009), and ergosterolide derivates with an unusual pentalactone B-ring exhibiting cytotoxic activity (Cui et al. 2010). Metabolites derived from fungi associated with red seaweeds (such as Aspergillus spp., Curvularia sp., Drechslera dematioidea, and Penicillium spp.) include curvularin-type macrolides showing antibacterial, antifungal, and algicide properties (Dai et al. 2011), antimicrobial indoloterpenes (Qiao et al. 2010), sesquiterpenoids with antiplasmodial activity (Osterhage et al. 2002), antimicrobial monoterpene, and tetracyclic diterpenes (Gao et al. 2011a). Acremonium sp. isolated from Plocamium sp. produce aromatic pentaketides of the dihydroisocoumarins class (Pontius
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et al. 2008a). An Epicoccum sp. associated with Fucus vesiculosus produces a novel antioxidant epicoccone (AbdelLateff et al. 2003). Further, we are now summarizing the potential bioactivities of important seaweed-associated fungal strains of genera Aspergillus and Penicillium, in view of their wide abundance in most of the seaweeds as well as owing to their pharmaceutical and industrial applications. Aspergillus Aspergillus spp. are common colonizers of marine seaweeds and produce numerous potential pharmacological compounds. Phenylahistin (Fig. 3a) was extracted from a marine algae associated A. ustus and showed cytotoxic activity towards human cancer cell lines (P388 cell lines) and particularly inhibited cell cycle progression in the G2/M phase (Kanoh et al. 1997, 1999). Later, it was found that it inhibited tubulin polymerization at a submicromolar concentration in vivo condition via binding at the colchicine binding site (Kanoh et al. 1999). A new isochroman derivative, pseudodeflectusin (Fig. 3b) with cytotoxicity to human cancer lines NUGC-3, HeLa-S3, and HL-60 (LD50 values of 49, 47, and 39 μM, respectively) was obtained from Aspergillus pseudodeflectus, an epibiont of Sargassum fusiform (Ogawa et al. 2004). Cui et al. (2009) isolated benzodiazepine analogue, 2-hydroxycircumdatin C from A. ochraceus derived from brown alga Sargassum kjellmanianum and it displayed significant antioxidant 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity (IC50 9.9 μM), almost 8.9-fold more potent than that of synthetic positive control, butylated hydroxytoluene (BHT). Further, Cui et al. (2010) also isolated a rare 7norsteoid with an unusual pentalactone B-ring system, 7-Norergosterolide (Fig. 3c) from the same endophytic fungus. This compound showed cytotoxicity against NCI-H460, SMMC7721, and SW1990 cell lines with IC50 values of 5, 7.0, and 28 μg/mL, respectively (Cui et al. 2010). This fungal endophyte also produced a new steroid derivative, 3 β,11αdihydroxyergosta-8,24(28)-dien-7-one and showed cytotoxicity Fig. 3 Some representatives of structurally potential bioactive isolated from seaweed-associated fungi. a phenylahistin; b pseudodeflectusin; c 7-Norergosterolide; d citrinal A; and e chromanone A
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against SMMC-7721 cell line (IC50 28.0 μg/mL) (Cui et al. 2010). From the culture of Aspergillus sp., (associated with Sargassum sp.) two new terpeptin analogs were discovered (JBIR-81 and JBIR-82) along with a known terpeptin. JBIR-81 JBIR-82 and known terpeptin were showed strong protective activity against L-glutamate toxicity in cells with IC50 values of 0.7, 1.5, and 0.9 μM, respectively. The activity was comparable to α-tocopherol (IC50 8.8 μM), a representative antioxidant (Izumikawa et al. 2010). Li et al. (2005) extracted five bioactive compounds namely, epoxydone, (+)-epoxydone monoacetate, gentisyl alchol, 3chlorogentisyl alcohol, and methylhydroquinone (of the class epoxycyclohexenones and aromatic polyols) from an organic extract of Aspergillus sp. derived from red alga Hypnea asidana, all of which showed potent antibacterial activities against MRSA and multidrug-resistant S. aureus with MIC values of 12.5, 12.5, 12.5, 50.0, and 6.2 μg/ mL, respectively. Miao et al. (2012) obtained 11 compounds from fungal endophyte Aspergillus versicolor, isolated from brown seaweed Sargassum thunbergii and out of them only three compounds, brevianamide M, 6,8-di-O-methylaverufin, and 6-O-methylaverufin showed antibacterial activities against E. coli and S. aureus. Recently, Suja et al. (2014) showed that the purified fractions F7 and F8 of ethyl acetate extract obtained from A. terrus displayed cytotoxicity against HepG2 cancer cell lines. The fractions F7 and F8 were shown growth inhibition (GI50), total growth inhibition (TGI), and ethality (LC50) with 10, >80,>80, and >80>80 respectively. Penicillium Marine-derived Penicillium is also an important source of pharmacologically active metabolites. Zhu et al. (2009) obtained citrinal A, along with two other previously known compounds ( c i t r i n i n a n d 2, 3 , 4 - t r i m e t hyl- 5,7 -dih yd roxy -2, 3dihydrobenzofuran) from Penicillium sp. isolated from a green alga Blidingia minima. The study particularly determined structure and stereochemistry of citrinal A which is a novel tricyclic
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compound with a rare tetrahydro-2H-benzofuro[7-b][1,4]dioxin9(3H)-one skeleton (Fig. 3d) and showed cytotoxicity against A549 (IC50 80.7 μmol/L) and HL-60 cell lines (IC50 143.1 μmol/ L). Gamal-Eldeen et al. (2009) isolated a new chromone derivative, chromanone A [2-(hydroxymethyl)-8-methoxy-3-methyl4H-chromen-4-one] (Fig. 3e) from Penicillium sp. associated with Ulva sp., that exhibits anti-tumorigenesis properties via modulation of carcinogen metabolizing enzymes (such as NADPH-cytochrome P-450 (NADPH-CYP) reductase or isozymes of CYP or glutathione S-transferases) and protection from DNA damage. Gao et al. (2011a) extracted several tetracyclic diterpenes, conidiogenones from Penicillium chrysogenum QEN-24S associated with red alga Laurencia sp., of which conidiogenone B showed potent activity against methicillin resistant S. aureus, Staphylococcus epidermidis, P. aeruginosa, and P. fluorescens (each with a MIC value of 8 μg/mL) along with a week antifungal activity against C. albicans (MIC, 128 mg/mL) whereas conidiogenol showed activity against P. fluorescens and S. epidermidis (each with a MIC value of 16 μg/mL). In another study of chemical investigation of this fungus (P. chrysogenum QEN-24S) led to discoveries of four new compounds, polyketide derivative penicitides A and B, 2-(2,4-dihydroxy-6methylbenzoyl)-glycerol, and penicimonoterpene. Among them, penicitides A displayed cytotoxic activity against the human hepatocellular liver carcinoma, HepG2 cell line (IC50 32 μg/mL) while penicimonoterpene showed strong inhibitory activity against plant pathogenic insect Alternaria brassicae in dual culture test with 17 mm inhibition zone at the concentration of 20 μg/disk (Gao et al. 2011b). Further, extensive spectroscopic analysis revealed two more novel polyoxygenated steroids compounds, namely, penicisteroids A and B (Gao et al. 2011c). Penicisteroids A is structurally unique compound containing tetrahydroxy and C-16-acetoxy groups and showed potent antifungal activity against A. niger with a clear inhibition zone of 18 mm diameter at the concentration of 20 μg/disk. It also displayed selective activity against the tumor cell lines HeLa, SW1990, and NCI-H460 with the IC50 of 15, 31, and 40 μg/mL respectively. Two pinophilins, a class of hydrogenated azaphilones along with the co-isolated metabolite Sch 725680 were isolated from Penicillium pinophilum associated with Ulva fasciata. These compounds selectively inhibited the activities of mammalian DNA polymerases (pols), A (pol g), B (pols a, d, and 3), and Y (pols h, i, and k) families and the growth and proliferation of several human tumor cell lines (Myobatake et al. 2012).
Bioactivities of some other seaweed associated fungal groups Some other fungal groups also produce potential bioactive compounds. For instances, Osterhage et al. (2000) isolated
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ascosalipyrrolidinone A (3R,4S,5S,6S,8R,10R)-3-[1,2,4a,5,6, 7,8,8a-octahydro-3,6,8-trimethyl-2-[(E)-1-methyl-1propenyl]-1-naphthalenyl]carbonyl-5-butoxy-1,5-dihydro-5methyl- 2H-pyrrol-2-one) from endophytic obligate marine fungus Ascochyta salicorniae associated with Ulva sp. This compound displayed antiplasmodial activity toward Plasmodium falciparum strains K1 (IC50 736 ng/mL) and NF 54 (IC50 378 ng/mL). It also showed antimicrobial activity against Bacillus megaterium (5 mm), Mycotypha microsporum (4 mm), and Microbotryum violaceum (2 mm) at a concentration of 50μg per filter disk and inhibited tyrosine kinase p56lck to 70 % of its activity at a concentration of 40μg/mL and to 23 % at a concentration of 200μg/mL. Wang et al. (2006) identified A novel 2H-benzopyran derivative, chaetopyranin exhibiting moderate DPPH radical scavenging activity (IC50 35 μg/mL) and a weak to moderate cytotoxic activities against three tumor cell lines human microvascular endothelial cells, HMEC (IC50 15.4 μg/mL), hepatocellular carcinoma cells, SMMC 7221 (IC50 28.5 μg/mL), and human lung epithelial cells, A549 (IC50 39.1 μg/mL). This compound was isolated from Chaetomium globosum derived from Polysiphonia urceolata (Wang et al. 2006). Naganuma et al. (2008) reported 1-deoxyrubralactone, a novel specific inhibitor of families X (rat pol β) and Y (human pol κ) of eukaryotic DNA polymerases from a fungal strain derived from sea algae. Its IC50 values on family X and family Y were 11.9 and 59.8 μM, respectively. Pontius et al. (2008b) isolated a novel heterodimeric chromanone compound, noduliprevenone exhibiting cancer chemopreventive potential from algal endophytic fungus Nodulisporium sp. This compound contained two uniquely modified xanthone-derived units, including four chiral centers and a chiral axis. This compound was found to be a competitive inhibitor of cytochrome (P450) 1A activity with an IC50 value 6.5±1.6 μM and induced at the same time twofold NAD(P)H:quinone reductase (QR) activity in Hepa 1c1c7 mouse culture cells with a concentration of 5.3±1.1 μM. Pontius et al. (2008c) also isolated two dimeric xanthone derivatives, monodictyochromes A and B from algicolous fungus Monodictys putredinis. Both these compounds displayed cancer chemopreventive potential and inhibited cytochrome (P450) 1A activity with IC50 values of 5.3 and 7.5 μM, respectively, as well as aromatase inhibitory activity, with IC50 values of 24.4 and 16.5 μM. In addition, they displayed moderate activity as inducers of QR in cultured mouse Hepa 1c1c7 cells, with CD values (concentration required to double the specific activity of QR) of 22.1 and 24.8 μM, respectively. Moreover, Thirunavukkarasu et al. (2011) and Suryanarayanan et al. (2012b) showed that fungal endosymbionts of seaweeds (such as Alternaria, Chaetomium, Cladosporium, Colletotrichum, Curvularia, Nigrospora, Paecilomyces, Phaeotrichoconis, Phoma, and Pithomyces are a good source of the therapeutic enzyme L-asparaginase which is used in the treatment of acute lymphoblastic leukemia.
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Biotechnology approach for finding new potential bioactive products It is known that 99 % of the microorganisms present in natural environments are not willingly culturable (Ward et al. 1990; Handelsman 2004; Streit et al. 2004) and many favorable reasons has suggested for this cause (Simu and Hagstrom 2004). Thus, it can be concluded that majority of microorganisms are not accessible for phylogenetic and functional analysis using classical culture-dependent methods (Ward et al. 1990; Handelsman 2004; Krohn-Molt et al. 2013). Recent advances in nucleic acid-based techniques and sequence technologies have endorsed for the diversity and functional analysis of bacteria within a microbial community without the use of laborious microscopy techniques (Rastogi and Sani 2011). These advancements have led to identify several novel enzymes from diverse sources including the green alga U. australis associated with bacterial communities (Yung et al. 2011; Schallmey et al. 2011; Chow et al. 2012) and antibiotics such as terragine, acyltyrosines, turbomycin A and B (Brady and Clardy 2000; Wang et al. 2000; Gillespie et al. 2002). Even, application of such techniques has greatly been enhanced for identification of seaweed-associated microbial communities and functional analysis of associated communities (Penesyan et al. 2010, 2013b; Burke et al. 2011; Bondoso et al. 2013; Hollants et al. 2013). For instance, using metagenomic approach, a biosynthetic gene cluster of antifungal drug tambjamineYP1 was successfully determined in P. tunicata associated with U. australis via constructed E. coli fosmid library (Burke et al. 2007). Notably, this bacterial genus is also known for various biological activities as aforementioned. Furthermore, functional genomics-based studies of bioactives from bacteria derived from diverse sources represent a powerful tool for identifying novel pharmaceutical drugs. Frequency of metagenomic clones was significantly low due to heterologous expression of clone libraries in different host (Uchiyama and Miyazaki 2009; Ekkers et al. 2012) or toxic effect of cloned genes (Kimelman et al. 2012). However, it is also mentioned that such screening are targeted and likelihood gene of interest may not be distributed in all the members of particular communities (Uchiyama and Miyazaki 2009; Penesyan et al. 2013a). For example, only three clones of the green alga U. australis associated bacteria showed antifungal activity against C. albicans out of 884 clones (Burke et al. 2007). Recently, Penesyan et al. (2013b) developed 2880 fosmid clone libraries using DNA of six bacterial strains which were previously obtained from green alga U. australis and red alga D. pulchra, already known to have antibacterial activities. Subsequently, these clones were screened for antibacterial and antinematode activities. Out of them, 13 clones produced compounds or enzymes with antibacterial and antinematode activities. The results of this study suggest that
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a pre-selection of bioactive-producing genomes could help in improving the hit-rates in metagenomic screening. Despite low hit rate of functional metagenomic analysis for searching bioactive compounds from diverse sources, it can be improved by using appropriate host strains, e.g., some similarities between codon uses and the presence of common biosynthetic pathway for particular metabolites of host and clone libraries (Butzin et al. 2010; Penesyan et al. 2013b). Additionally, Foerstner et al. (2008) employed metagenomics Shotgun Data for identifying novel genes of type I polyketide synthases and non-ribosomal peptide synthetases (NRPS). These genes are found to be generally constituted part of biosynthetic pathways of production of bioactive compounds (Foerstner et al. 2008), and it enhances the chance of hit rate in metagenomic screening. Recently, a clone, 19 F10 of Penesyan et al. (2013b) study was shown sequence similarity to NRPS gene and homology with the NRPS gene indC from Erwinia chrysanthemi (Reverchon et al. 2002), and bpsA from Streptomyces lavendulae (Takahashi et al. 2007). Despite these few successes, there is still a serious need for the advancement of the metagenomic approach where heterologous gene expression barrier can be overcome and hit rate can be increased.
Conclusions and future directions Marine environment and organisms are potential sources of bioactive compounds, and the exploration of seaweedassociated microbes promises to deliver novel bioactives with potential pharmaceutical applications. Unique seaweedmicrobial interaction has attracted a large group of researchers for understanding their chemical interactions and studies of microbial communities. Development of new tools and techniques significantly contribute to the discovery of next-generation, bioactive compounds. Metagenomic (including functional metagenomics) approaches for exploring bioactive compounds form seaweed-associated microorganism is still in its infancy, due to low hit ratio and heterologous gene expression in foreign host. These high-throughput genomic approaches will surely help in identifying novel metabolites from uncultivable seaweed-associated microbes. Notably, there is a requirement to improve such technique to overcome barrier of heterologous expression. Probably, choosing appropriate host and highly expected clone sources of bioactive producers. So far, a number of novel bioactive compounds have been obtained from seaweed-associated bacterial and fungal sources, which represent seaweed as another hub of novel marine derived natural products, despite there are several studies which only screened microorganism for antimicrobial compounds without identified potential molecules (Suryanarayanan et al. 2010, 2012; Suryanarayanan 2012;
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Suryanarayanan et al. 2012; Suvega and kumar 2014). Seaweed-associated microbes provide unique and novel metabolites of unprecedented structures, with antibacterial, antifungal, antiviral, antiplasmodial, nematicidal, anti-inflammatory, anticancer, and antiangiogenic activities. Thus, these bioactive compounds may provide high-quality drug candidates for pharmaceutical applications, as well as agricultural and industrial applications. Therefore, the exploration of seaweed-associated microbes using new tools and techniques, such as those of high-throughput genomic and metagenomic approaches, will led to the discovery of more novel bioactive natural products in future, and will help in exploiting their biotechnological potential Acknowledgments CSIR is gratefully acknowledged for awarding the Senior Research Fellowship (SRF) to R.P. Singh and P. Kumari. CSIRCSMCRI also thanked for facilities and encouragement provided while preparing this manuscript.
References Abdel-Lateff A, Fisch KM, Wright AD, König GM (2003) A new antioxidant isobenzofuranone derivative from the algicolous marine fungus Epicoccum sp. Planta Med 69:831–834 Armstrong E, Yan L, Boyd KG, Wright PC, Burgess JG (2001) The symbiotic role of marine microbes on living surfaces. Hydrobiologia 461:37–40 Beattie P, Tan K, Bourne RM, Leach D, Rich PR, Ward FB (1994) Cloning and sequencing of four structural genes for the Na(+)translocating NADH-ubiquinone oxidoreductase of Vibrio alginolyticus. FEBS Lett 356:333–338 Bondoso J, Balague V, Gasol JM, Lage OM (2013) Community composition of the Planctomycetes associated with different macroalgae. FEMS Microbiol Ecol 88:445–456 Brady SF, Clardy J (2000) Long-chain N-acyl amino acid antibiotics isolated from heterologously expressed environmental DNA. J Am Chem Soc 122:12903–12904 Braña AF, Fiedler HP, Nava H, González V, Sarmiento-Vizcaíno A, Molina A, Acuña JL, García LA, Blanco G (2014) Two Streptomyces species producing antibiotic, antitumor, and antiinflammatory compounds are widespread among intertidal macroalgae and deep-sea coral reef invertebrates from the central cantabrian sea. Microb Ecol. doi:10.1007/s00248-014-0508-0 Bruhn JB, Gram L, Belas R (2007) Production of antibacterial compounds and biofilm formation by Roseobacter species are influenced by culture conditions. Appl Environ Microbiol 73:442–450 Bugni TS, Ireland CM (2004) Marine-derived fungi: a chemically and biologically diverse group of microorganisms. Nat Prod Rep 21: 143–163 Burgess JG, Jordan EM, Bregu M, Mearns-Spragg A, Boyd KG (1999) Microbial antagonism: a neglected avenue of natural products research. J Biotechnol 70:27–32 Burgess JG, Boyd KG, Armstrong E, Jiang Z, Yan L, Berggren M, May U, Pisacane T, Granmo A, Adams DR (2003) The development of a marine natural product-based antifouling paint. Biofouling 19:197– 205 Burke C, Thomas T, Egan S, Kjelleberg S (2007) The use of functional genomics for the identification of a gene cluster encoding for the biosynthesis of an antifungal tambjamine in the marine bacterium Pseudoalteromonas tunicata. Environ Microbiol 9:814–818
Appl Microbiol Biotechnol (2015) 99:1571–1586 Burke C, Steinberg P, Rusch D, Kjelleberg S, Thomas T (2011) Bacterial community assembly based on functional genes rather than species. Proc Natl Acad Sci U S A 108:14288–14293 Butzin NC, Owen HA, Collins MLP (2010) A new system for heterologous expression of membrane proteins: Rhodospirillum rubrum. Protein Expr Purif 70:88–94 Chakraborty K, Thilakan B, Raola VK (2014) Polyketide family of novel antibacterial 7-o-methyl-5′-hydroxy-3′-heptenoate-macrolactin from seaweed-associated Bacillus subtilis MTCC 10403. J Agric Food Chem. doi:10.1021/jf504845m Cho JY, Kim MS (2012) Induction of antifouling diterpene production by Streptomyces cinnabarinus PK209 in co-culture with marinederived Alteromonas sp. KNS-16. Biosci Biotechnol Biochem 76: 1849–1854 Chow J, Kovacic F, Dall Antonia Y, Krauss U, Fersini F, Schmeisser C, Lauinger B, Bongen P, Pietruszka J, Schmidt M, Menyes I, Bornscheuer UT, Eckstein M, Thum O, Liese A, MuellerDieckmann J, Jaeger KE, Streit WR (2012) The metagenomederived enzymes LipS and LipT increase the diversity of known lipases. PLoS One 7:e47665 Clardy J, Fischbach MA, Walsh CT (2006) New antibiotics from bacterial natural products. Nat Biotechnol 24:1541–1550 Cui CM, Li XM, Li HF, Gao SS, Wang BG (2009) Benzodiazepine alkaloids from marine-derived endophytic fungus Aspergillus ochraceus. Helv Chim Acta 92:1366–1370 Cui CM, Li XM, Meng L, Li CS, Huang CG, Wang BG (2010) 7-Norergosterolide; a pentalactone- containing norsteroid and related steroids from the marine- derived endophytic Aspergillus ochraceus EN-31. J Nat Prod 73:1780–1784 Dai J, Krohn K, Flörke U, Pescitelli G, Kerti G, Papp T, Kövér KE, Bényei AC, Draeger S, Schulz B, Kurtán T (2011) Curvularintype metabolites from the fungus Curvularia sp. isolated from a marine alga. Eur J Org Chem 36:6928–6937 Debnath M, Paul AK, Bisen PS (2007) Natural bioactive compounds and biotechnological potential of marine bacteria. Curr Pharm Biotechnol 8:253–260 Dobretsov SV, Qian PY (2002) Effect of bacteria associated with the green alga Ulva reticulata on marine micro- and macrofouling. Biofouling 18:217–228 Egan S, James S, Holmstrom C, Kjelleberg S (2001) Inhibition of algal spore germination by the marine bacterium Pseudoalteromonas tunicata. FEMS Microbiol Ecol 35:67–73 Egan S, James S, Holmstrom C, Kjelleberg S (2002) Correlation between pigmentation and antifouling compounds produced by Pseudoalteromonas tunicata. Environ Microbiol 4:433–442 Egan S, Thomas T, Kjelleberg S (2008) Unlocking the diversity and biotechnological potential of marine surface associated microbial communities. Curr Opin Microbiol 11:219–225 Ekkers DM, Cretoiu MS, Kielak AM, Elsas JD (2012) The great screen anomaly—a new frontier in product discovery through functional metagenomics. Appl Microbiol Biotechnol 93:1005–1020 Elsebai MF, Kehraus S, Lindequist U, Sasse F, Shaaban S, Gütschow M, Josten M, Sahl HG, König GM (2010) Antimicrobial phenalenone derivatives from the marine-derived fungus Coniothyrium cereal. Org Biomol Chem 9:802–808 Engel S, Jensen PR, Fenical W (2002) Chemical ecology of marine microbial defense. J Chem Ecol 28:1971–1985 Fenical W (1993) Chemical studies of marine bacteria: developing a new resource. Chem Rev 93:1673–1683 Fenical W, Jensen PR (1991) Marine Biotechnology. Plenum Press, New York Ferreira CV, Bos CL, Versteeg HH, Justo GZ, Duran N, Peppelenbosch MP (2004) Molecular mechanism of violacein-mediated human leukemia cell death. Blood 104:1459–1464
Author's personal copy Appl Microbiol Biotechnol (2015) 99:1571–1586 Flewelling AJ, Johnson JA, Gray CA (2013) Isolation and bioassay screening of fungal endophytes from North Atlantic marine macroalgae. Bot Mar 56:287–297 Foerstner KU, Doerks T, Creevey CJ, Doerks A, Bork PA (2008) Computational screen for type I polyketide synthases in metagenomics shotgun data. PLoS One 3:e3515 Franks A, Haywood P, Holmstrom C, Egan S, Kjelleberg S, Kumar N (2005) Isolation and structure elucidation of a novel yellow pigment from the marine bacterium Pseudoalteromonas tunicata. Molecules 10:1286–1291 Franks A, Egan S, Holmström C, James S, Lappin-Scott H, Kjelleberg S (2006) Inhibition of fungal colonization by Pseudoalteromonas tunicata provides a competitive advantage during surface colonization. Appl Environ Microbiol 72:6079–6087 Fudou R, Iizuka T, Yamanaka S (2001) Haliangicin, a novel antifungal metabolite produced by a marine Myxobacterium 1. Fermentation and biological characteristics. J Antibiot 54:149–152 Furbino LE, Godinho VM, Santiago IF, Pellizari FM, Alves TMA, Zani CL, Junior PAS, Romanha AJ, Carvalho AJO, Gil LHVG, Rosa CA, Minnis AM, Rosa LH (2014) Diversity patterns; ecology and biological activities of fungal communities associated with the endemic macroalgae across the Antarctic peninsula. Microb Ecol 67:775–787 Gamal-Eldeen AM, Abdel-Lateff A, Okino T (2009) Modulation of carcinogen metabolizing enzymes by chromanone A; a new chromone derivative from algicolous marine fungus Penicillium sp. Environ Toxicol Phar 28:317–322 Gandhi NM, Nazareth J, Divekar PV, Kohl H, Desouza NJ (1973) Magnesidin, a novel magnesium-containing antibiotic. J Antibiot 26:799–801 Gao SS, Li XM, Du FY, Li CS, Proksch P, Wang BG (2011a) Secondary metabolites from a marine-derived endophytic fungus Penicillium chrysogenum QEN- 24S. Mar Drugs 9:59–70 Gao SS, Li XM, Du FY, Li CS, Proksch P, Wang BG (2011b) Penicisteroids A and B; antifungal and cytotoxic polyoxygenated steroids from the marine alga-derived endophytic fungus Penicillium chrysogenum QEN- 24S. Bioorg Med Chem Lett 21: 2894–2897 Gao SS, Li XM, Du FY, Li CS, Proksch P, Wang BG (2011c) Conidiogenones H and I; two new diterpenes of cyclopiane class from a marine-derived endophytic fungus Penicillium chrysogenum QEN-24S. Chem Biodivers 8:1748–1753 Gauthier MJ (1976) Morphological, physiological, and biochemical characteristics of some violet-pigmented bacteria isolated from seawater. Can J Microbiol 22:138–149 Gauthier MJ (1979) Alteromonas rubra sp. nov a new marine antibioticproducing bacterium. Int J Syst Bacteriol 26:459–466 Gauthier MJ, Breittmayer VA (1979) A new antibiotic-producing bacterium from seawater: Alteromonas aurantia sp.nov. Int J Syst Bacteriol 29:366–372 Gerard J, Lloyd R, Barsby T, Haden P, Kelly MT, Andersen RJ (1997) Antimycobacterial cyclic depsipeptides produced by two pseudomonads isolated from marine habitats. J Nat Prod 60:223–229 Gillespie DE, Brady SF, Bettermann AD, Cianciotto NP, Liles MR, Rondon MR, Clardy J, Goodman RM, Handelsman J (2002) Isolation of antibiotics turbomycin A and B from a metagenomic library of soil microbial DNA. Appl Environ Microbiol 68:4301– 4306 Godinho VM, Furbino LE, Santiago IF, Pellizzari FM, Yokoya NS, Pupo D, Alves TM, Junior PA, Romanha AJ, Zani CL, Cantrell CL, Rosa CA, Rosa LH (2013) Diversity and bioprospecting of fungal communities associated with endemic and cold-adapted macroalgae in Antarctica. ISME J 7:1434–1451 Goecke F, Labes A, Wiese J, Imhoff JF (2010) Chemical interactions between marine macroalgae and bacteria. Mar Ecol Prog Ser 409: 267–300
1583 Goecke F, Thiel V, Wiese J, Labes A, Imhoff JF (2013) Algae as an important environment for bacteria—Phylogenetic relationships among new bacterial species isolated from algae. Phycologia 52: 14–24 Goto T, Takahashi S, Kishi Y, Hirata Y (1965) Tetrodotoxin. Tetrahedron 21:2059–2088 Gulder TAM, Moore BS (2009) Chasing the treasures of the sea— Bacterial marine natural products. Curr Opin Microbiol 12:252–260 Handelsman J (2004) Metagenomics: Application of genomics to uncultured microorganisms. Microbiol Mol Biol Rev 68:669–685 Harder T (2009) Marine epibiosis: Concepts, ecological consequences and host defence. In: Costerton JW (ed) Marine and Industrial Biofouling. Springer, Berlin, pp 219–231 Hayashi M, Hirai K, Unemoto T (1994) Cloning of the Na(+)translocating NADH-quinone reductase gene from the marine bacterium Vibrio alginolyticus and the expression of the beta-subunit in Escherichia coli. FEBS Lett 356:330–332 Hayashi M, Hirai K, Unemoto T (1995) Sequencing and the alignment of structural genes in the nqr operon encoding the Na+-translocating NADH-quinone reductase from Vibrio alginolyticus. FEBS Lett 363:75–77 Hayashi M, Shibata N, Nakayama Y, Yoshikawa K, Unemoto T (2002) Korormicin insensitivity in Vibrio alginolyticus is correlated with a single point mutation of Gly-140 in the NqrB subunit of the Na(+)translocating NADH-quinone reductase. Arch Biochem Biophys 401:173–177 Hollants J, Leliaert F, Verbruggen H, Willems A, De-Clerck O (2013) Permanent residents or temporary lodgers: characterizing intracellular bacterial communities in the siphonous green alga Bryopsis Proc R Soc Lond B 20122659 Holmstrom C, Kjelleberg S (1999) Marine Pseudoalteromonas species are associated with higher organisms and produce active extracellular agents. FEMS Microbiol Ecol 30:285–293 Holmström C, Egan S, Franks A, McCloy S, Kjelleberg S (2002) Antifouling activities expressed by marine surface associated Pseudoalteromonas species. FEMS Microbiol Ecol 41:47–58 Imamura N, Nishijima M, Takadera T, Adachi K (1997) New anticancer antibiotics pelagiomicins, produced by a new marine bacterium Pelagiobacter variabilis. J Antibiot 50:8–12 Ismail-Ben Ali A, El Bour M, Ktari L, Bolhuis H, Ahmed M, Boudabous A, Stal LJ (2012) Jania rubens-associated bacteria: Molecular identification and antimicrobial activity. J Appl Phycol 24:525–534 Isnansetyo A, Horikawa M, Kamei Y (2001) In vitro antimethicillinr e s i s ta n t Staphylococcus au reu s a ct i v i ty of 2, 4 diacetylphloroglucinol produced by Pseudomonas sp. AMSN isolated from a marine alga. J Antimicrob Chemother 47:719–730 Izumikawa M, Hashimoto J, Takagi M, Shin-ya K (2010) Isolation of two new terpeptin analogs—JBIR-81 and JBIR-82 from a seaweedderived fungus, Aspergillus sp. SpD081030G1f1. J Antibiot 63: 389–391 Jamal MT, Morris PC, Hansen R, Jamieson DJ, Burgess JG, Austin B (2006) Recovery and characterization of a 30.7- kDa protein from Bacillus licheniformis associated with inhibitory activity against methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococci, and Listeria monocytogenes. Mar Biotechnol 8:587– 592 JanakiDevi V, YokeshBabuM, Umarani R, Kumarguru A (2013) Antagonistic activity of seaweed associated bacteria against human pathogens. Int J Cur Micobiol App Sci 2:140–147 Jaruchoktaweechai C, Suwanboriux K, Tanasupawatt S, Kittakoop P, Menasveta P (2000) New macrolactins from a marine Bacillus sp. ScO26. J Nat Prod 63:984–986 Jiang Z, Mearns-Spragg A, Adams DR, Wright PC, Burgess JG (2001) Two diketopiperazines and one halogenated phenol from cultures of the marine bacterium, Pseudoalteromonas luteoviolacea. Nat Prod Lett 14:435–440
Author's personal copy 1584 Kamei Y, Isnansetyo A (2003) Lysis of methicillin-resistant Staphylococcus aureus by 2, 4-diacetylphloroglucinol produced by Pseudomonas sp. AMSN isolated from a marine alga. Int J Antimicrob Agents 21:71–74 Kanagasabhapathy M, Sazaki H, Haldar S, Yamasaki S, Ngata S (2006) Antibacterial activities of marine epibiotic bacteria isolated from brown algae. Ann Microb 56:167–173 Kanagasabhapathy M, Sasaki H, Nagata S (2008) Phylogenetic identification of epibiotic bacteria possessing antimicrobial activities isolated from red algal species of Japan. World J Microbiol Biotechnol 24: 2315–2321 Kanagasabhapathy M, Yamazaki G, Ishida A, Sasaki H, Nagata S (2009) Presence of quorum-sensing inhibitor-like compounds from bacteria isolated from the brown alga Colpomenia sinuosa. Lett Appl Microbiol 49:573–579 Kanoh K, Kohno S, Asari T, Harada T, Katada J, Muramatsu M, Kawashima H, Sekiya H, Uno I (1997) (−)-phenylahistin: a new mammalian cell cycle inhibitor produced by Aspergillus ustus. Bioorg Med Chem Lett 7:2847–2852 Kanoh K, Kohno S, Katada J, Hayash Y, Muramatsu M, Uno I (1999) Antitumor activity of phenylahistin in vitro and in vivo. Bios Biotechol Biochem 63:1130–1133 Kim H, Kim W, Ryoo I, Kim C, Suk J, Han K, Hwang S, Yoo I (1997) Neuronal cell protection activity of macrolactin A produced by Actinomadura sp. J Microbiol Biotechnol 7:429–434 Kimelman A, Levy A, Sberro H, Kidron S, Leavitt A, Amitai G, YoderHimes DR, Wurtzel O, Zhu Y, Rubin EM, Sorek R (2012) A vast collection of microbial genes that are toxic to bacteria. Genome Res 22:802–809 Kodach LL, Bos CL, Durán N, Peppelenbosch MP, Ferreira CV, Hardwick JC (2006) Violacein synergistically increases 5fluorouracil cytotoxicity, induces apoptosis and inhibits Aktmediated signal transduction in human colorectal cancer cells. Carcinogenesis 27:508–516 Krohn-Molt I, Wemheuer B, Alawi M, Poehlein A, Güllert S, Schmeisser C, Pommerening-Röser A, Grundhoff A, Daniel R, Hanelt D, Streit WR (2013) Metagenome survey of a multispecies and algaassociated biofilm revealed key elements of bacterial-algal interactions in photobioreactors. Appl Environ Microbiol 79:6196–6206 Kumar V, Rao D, Thomas T, Kjelleberg S, Egan S (2011) Antidiatom and antibacterial activity of epiphytic bacteria isolated from Ulva lactuca in tropical waters. World J Microbiol Biotechnol 27:1543–1549 Lachnit T, Blümel M, Imhoff JF, Wahl M (2009) Specific epibacterial communities on macroalgae: Phylogeny matters more than habitat. Aquat Biol 5:181–186 Lachnit T, Meske D, Wahl M, Harder T, Schmitz R (2011) Epibacterial community patterns on marine macroalgae are host-specific but temporally variable. Environ Microbiol 13:655–665 Lafi FF, Garson MJ, Fuerst JA (2005) Culturable bacterial symbionts isolated from two distinct sponge species (Pseudoceratina clavata and Rhabdastrella globostellata) from the Great Barrier Reef display similar phylogenetic diversity. Microb Ecol 50:213–220 Lane AL, Kubanek J (2008) Secondary metabolite defenses against pathogens and biofoulers. In: Amsler CH (ed) Algal chemical ecology. Springer, Berlin, pp 229–243 Lee CH, Ruben PC (2008) Interaction between voltage-gated sodium channels and the neurotoxin, tetrodotoxin. Channels (Austin) 2: 407–412 Lee YM, Kim MJ, Li H, Zhang P, Bao B, Lee KJ, Jung JH (2013) Marinederived Aspergillus species as a source of bioactive secondary metabolites. Mar Biotechnol 15:499–519 Lemos ML, Toranzo AE, Barja JL (1985) Antibiotic activity of epiphytic bacteria isolated from Inter-tidal seaweeds. Microbiol Ecol 11:149– 163 Li S, Norioka S, Sakiyama F (1998) Bacteriolytic activity and specificity of Achromobacter beta-lytic protease. J Biochem 124:332–339
Appl Microbiol Biotechnol (2015) 99:1571–1586 Li Y, Li X, Son BW (2005) Antibacterial and radical scavenging epoxycyclohexenones and aromatic polyols from a marine isolate of the fungus Aspergillus. Nat Prod Sci 11:136–138 Longford SR, Tujula NA, Crocetti G, Holmes AJ, Holmström C, Kjelleberg S, Steinberg PD, Taylor MW (2007) Comparisons of diversity of bacterial communities associated with three sessile marine eukaryotes. Aquat Microb Ecol 48:217–229 Loque CP, Medeiros AO, Pellizzari FM, Oliveira EC, Rosa CA, Rosa LH (2010) Fungal community associated with marine macroalgae from Antarctica. Polar Biol 33:641–648 Lu XL, QZh X, Shen YH, Liu XY, Jiao BH, Zhang WD, Ni KY (2008) Macrolactin S, a novel macrolactin antibiotic from marine Bacillus sp. Nat Prod Res 22:342–347 Ma Y, Liu P, Yu S, Li D, Cao S (2009) Inhibition of common fouling organisms in mariculture by epiphytic bacteria from the surfaces of seaweeds and invertebrates. Acta Ecol Sin 29:222–226 Marshall K, Joint I, Callow ME, Callow JA (2006) Effect of marine bacterial isolates on the growth and morphology of axenic plantlets of the green alga Ulva linza. Microb Ecol 52:302–310 Mathan S, Subramanian V, Nagamony S, Ganapathy K (2013) Isolation of endophytic fungi from marine algae and its bioactivity. Int J Res Pharm Sci 4:45–49 Matsuo Y, Suzuli M, Kasai H, Shizuri Y, Harayama S (2003) Isolation and phylogenetic characterization of bacteria capable of inducing differentiation in the green alga Monostroma oxyspermum. Environ Microbiol 5:25–35 Matsuo Y, Imagawa H, Nishizawa M, Shizuri Y (2005) Isolation of an algal morphogenesis inducer from a marine bacterium. Science 307: 1598 Matz C, Webb JS, Schupp PJ, Phang SY, Penesyan A, Egan S, Steinberg P, Kjelleberg S (2008) Marine biofilm bacteria evade eukaryotic predation by targeted chemical defense. PLoS One 3:e2744 Miao FP, Li XD, Liu XH, Cichewicz RH, Ji NY (2012) Secondary metabolites from an algicolous Aspergillus versicolor strain. Mar Drugs 10:131–139 Molinski TF, Dalisay DS, Lievens SL, Saludes JP (2009) Drug development from marine natural products. Nat Rev Drug Discov 8:69–85 Mondol MA, Kim JH, Lee HS, Lee YJ, Shin HJ (2011) Macrolactin W, a new antibacterial macrolide from a marine Bacillus sp. Bioorg Med Chem Lett 21:3832–3835 Murakami A, Miyashita H, Iseki M, Adachi K, Mimuro M (2004) Chlorophyll d in an epiphytic cyanobacterium of red algae. Science 303:1633 Myobatake Y, Takeuchi T, Kuramochi K, Kuriyama I, Ishido T, Hirano K, Sugawara F, Yoshida H, Mizushina Y (2012) Pinophilins A and B, inhibitors of mammalian A-, B-, and Y-family DNA polymerases and human cancer cell proliferation. J Nat Prod 75:135–141 Naganuma M, Nishida M, Kuramochi K, Sugawara F, Yoshida H, Mizushina Y (2008) 1-Deoxyrubralactone, a novel specific inhibitor of families X and Y of eukaryotic DNA polymerases from a fungal strain derived from sea algae. Bioorg Med Chem 16:2939–2944 Nagao T, Adachi K, Sakai M, Nishijima M, Sano H (2001) Novel macrolactins as antibiotic lactones from a marine bacterium. J Antibiot 54:333–339 Nakanishi K, Nishijima M, Nomoto AM, Yamazaki A, Saga N (1999) Requisite morphologic interaction for attachment between Ulva pertusa (Chlorophyta) and symbiotic bacteria. Mar Biotechnol 1: 107–111 Nakayama Y, Hayashi M, Yoshikawa K, Mochida K, Unemoto T (1999) Inhibitor studies of a new antibiotic, korormicin, 2-n-heptyl-4hydroxyquinoline N-oxide and Ag+toward the Na+-translocating NADH-quinone reductase from the marine Vibrio alginolyticus. Biol Pharm Bull 22:1064–1067 Ogawa A, Murakami C, Kamisuki S, Kuriyama I, Yoshida H, Sugawara F, Mizushina Y (2004) Pseudodeflectusin; a novel isochroman derivative from Aspergillus pseudodeflectus a parasite of the seaweed;
Author's personal copy Appl Microbiol Biotechnol (2015) 99:1571–1586 Sargassum fusiform; as a selective human cancer cytotoxin. Bioorg Med Chem Lett 14:3539–3543 Oliveira ALL, de Felício R, Debonsi HM (2012) Marine natural products: Chemical and biological potential of seaweeds and their endophytic fungi. Brazil J Pharmacogn 22:906–920 Osterhage C, Kaminsky R, König GM, Wright AD (2000) Ascosalipyrrolidinone A, an antimicrobial alkaloid, from the obligate marine fungus Ascochyta salicorniae. J Org Chem 5: 6412–6417 Osterhage C, König GM, Höller U, Wright AD (2002) Rare sesquiterpenes from the algicolous fungus Drechslera dematioidea. J Nat Prod 65:306–313 Penesyan A, Marshall-Jones Z, Holmstrom C, Kjelleberg S, Egan S (2009) Antimicrobial activity observed among cultured marine epiphytic bacteria reflects their potential as a source of new drugs. FEMS Microbiol Ecol 69:113–124 Penesyan A, Kjelleberg S, Egan S (2010) Development of novel drugs from marine surface associated microorganisms. Mar Drugs 8:438– 459 Penesyan A, Tebben J, Lee M, Thomas T, Kjelleberg S, Harder T, Egan S (2011) Identification of the antibacterial compound produced by the marine epiphytic bacterium Pseudovibrio sp. D323 and related sponge-associated bacteria. Mar Drugs 9:1391–1402 Penesyan A, Ballestriero F, Daim M, Kjelleberg S, Thomas T, Egan S (2013a) Assessing the effectiveness of functional genetic screens for the identification of bioactive metabolites. Mar Drugs 11:40–49 Penesyan A, Breider S, Schumann P, Tindall BJ, Egan S, Brinkhoff T (2013b) Epibacterium ulvae gen. nov sp. nov epibiotic bacteria isolated from the surface of a marine alga. Int J Syst Evol Microbiol 63: 1589–1596 Pontius A, Mohamed I, Krick A, Kehraus S, König GM (2008a) Aromatic polyketides from marine algicolous fungi. J Nat Prod 71:272–274 Pontius A, Krick A, Kehraus S, Foegen SE, Müller M, Klimo K, Gerhäuser C, König GM (2008b) Noduliprevenone: a novel heterodimeric chromanone with cancer chemopreventive potential. Chem Eur J 14:9860–9863 Pontius A, Krick A, Mesry R, Kehraus S, Foegen SE, Müller M, Klimo K, Gerhäuser C, König GM (2008c) Monodictyochromes A and B, dimeric xanthone derivatives from the marine algicolous fungus Monodictys putredinis. J Nat Prod 71:1793–1799 Prieto ML, O’Sullivan L, Tan SP, McLoughlin P, Hughes H, O’Connor PM, Cotter PD, Lawlor PG, Gardiner GE (2012) Assessment of the bacteriocinogenic potential of marine bacteria reveals lichenicidin production by seaweed-derived Bacillus spp. Mar Drugs 10:2280– 2299 Qiao MF, Ji NY, Liu XH, Li K, Zhu QM, Xue QZ (2010) Indoloditerpenes from an algicolous isolate of Aspergillus oryzae. Bioorg Med Chem Lett 20:5677–5680 Rao D, Webb JS, Holmström C, Case R, Low A, Steinberg P, Kjelleberg S (2007) Low densities of epiphytic bacteria from the marine alga Ulva australis inhibits settlement of fouling organisms. Appl Environ Microbiol 73:7844–7852 Rastogi G, Sani R (2011) Molecular techniques to assess microbial community structure, function, and dynamics in the environment. In: Ahmad I, Ahmad F, Pichtel J (eds) Microbes and Microbial Technology. Springer, New York, pp 29–57 Ravisankar A, Gnanambal MEK, Sundaram LR (2013) A Newly Isolated Pseudomonas sp. epibiotic on the seaweed, Padina tetrastromatica, off southeastern coast of India, reveals antibacterial action. Appl Biochem Biotechnol 171:1968–1985 Reverchon S, Rouanet C, Expert D, Nasser W (2002) Characterization of indigoidine biosynthetic genes in Erwinia chrysanthemi and role of this blue pigment in pathogenicity. J Bacteriol 184:654–665 Rungprom W, Siwu ERO, Lambert LK, Dechsakulwatana C, Barden MC, Kokpol U (2008) Cyclic tetrapeptides from marine bacteria
1585 associated with the seaweed Diginea sp. and the sponge Halisarca ectofibrosa. Tetrahedron 64:3147–3152 Schallmey M, Ly A, Wang C, Meglei G, Voget S, Streit WR, Driscoll BT, Charles TC (2011) Harvesting of novel polyhydroxyalkanaote (PHA) synthase encoding genes from a soil metagenome library using phenotypic screening. FEMS Microbiol Lett 321:150–156 Schulz B, Draeger S, Del Cruz TE, Rheinheimer J, Siems K, Loesgen S, Bitzer J, Schloerke O, Zeek A, Kock I, Hussain H, Dai J, Krohn K (2008) Screening strategies for obtaining novel; biologically active; fungal secondary metabolites from marine habitats. Bot Mar 51: 219–234 Silva-Aciares F, Riquelme C (2008) Inhibition of attachment of some fouling diatoms and settlement of Ulva lactuca zoospores by filmforming bacterium and their extracellular products isolated from biofouled substrata in Northern Chile. Elect J Biotechnol 11:60–70 Simu K, Hagstrom A (2004) Oligotrophic bacterioplankton with a novel single-cell life strategy. Appl Environ Microbiol 70:2445–2451 Singh RP, Reddy CRK (2014) Seaweed–microbial interactions: Key functions of seaweed-associated bacteria. FEMS Microbiol Ecol 88:213–230 Singh RP, Bijo AJ, Baghel RS, Reddy CRK, Jha B (2011a) Role of bacterial isolates in enhancing the bud induction in the industrially important red alga Gracilaria dura. FEMS Microbiol Ecol 76:381– 392 Singh RP, Mantri VA, Reddy CRK, Jha B (2011b) Isolation of seaweedassociated bacteria and their morphogenesis inducing capability in axenic cultures of the green alga Ulva fasciata. Aquat Biol 12:13–21 Streit WR, Daniel R, Jaeger KE (2004) Prospecting for biocatalysts and drugs in the genomes of non-cultured microorganisms. Curr Opin Biotechnol 15:285–290 Subramaniam S, Ravi V, Sivasubramanian A (2014) Synergistic antimicrobial profiling of violacein with commercial antibiotics against pathogenic microorganisms. Pharm Biol 52:86–90 Suja M, Vasuki S, Sajitha N (2014) Anticancer activities of compounds isolated from marine endophytic fungus Aspergillus terreus. World J Pharm Pharm Sci 3(6):661–672 Suresh M, Iyapparaj P, Anantharaman P (2014) Optimization, characterization and partial purification of bacteriocin produced by Staphylococcus haemolyticus MSM an isolate from seaweed. Biocatal Agric Biotechnol. doi:10.1016/j.bcab.2014.08.005 Suryanarayanan TS (2012) Fungal Endosymbionts of Seaweeds. In: Raghu Kumar C (ed) Biology of marine fungi; progress in molecular and subcellular biology. Springer, Berlin, pp 53–69 Suryanarayanan TS, Venkatachalam A, Thirunavukkarasu N, Ravishankar JP, Doble M, Geetha V (2010) Internal mycobiota of marine macroalgae from the Tamilnadu coast: distribution; diversity and biotechnological potential. Bot Mar 53:457–468 Suryanarayanan TS, Thirunavukkarasu N, Govindarajulu MB, Gopalan V (2012) Fungal endophytes: an untapped source of biocatalysts. Fungal Divers 54:19–30 Suvega T, Kumar KA (2014) Antimicrobial activity of bacteria associated with seaweeds against plant pathogens on par with bacteria found in seawater and sediments. British Microbiol Res J 4(841–85):2014 Tait K, Williamson H, Atkinson S, Williams P, Camara M, Joint I (2009) Turnover of quorum sensing signal molecules modulate crosskingdom signalling. Environ Microbiol 11:1792–1802 Takahashi H, Kumagai T, Kitani K, Mori M, Matoba Y, Sugiyama M (2007) Cloning and characterization of a Streptomyces single module type non-ribosomal peptide synthetase catalyzing a blue pigment synthesis. J Biol Chem 12:9073–9081 Tebben J, Tapiolas DM, Motti CA, Abrego D, Negri AP, Blackall LL, Steinberg PD, Harder T (2011) Induction of larval metamorphosis of the coral Acropora millepora by tetrabromopyrrole isolated from a Pseudoalteromonas bacterium. PLoS One 6:e19082 Tebben J, Motti C, Tapiolas D, Thomas-Hall P, Harder T (2014) A coralline algal-associated bacterium, Pseudoalteromonas strain J010,
Author's personal copy 1586 yields five new korormicins and a bromopyrrole. Mar Drugs 12: 2802–2815 Thirunavukkarasu N, Suryanarayanan TS, Murali TS, Ravishankar JP, Gummadi SN (2011) L-asparaginase from marine derived fungal endophytes of seaweeds. Mycosphere 2:147–155 Tran H, Ficke A, Asiimwe T, Höfte M, Raaijmakers JM (2007) Role of the cyclic lipopeptide massetolide A in biological control of Phytophthora infestans and in colonization of tomato plants by Pseudomonas fluorescens. New Phytol 175:731–742 Tsuda K, Ikuma S, Kawamura M, Tachikawa R, Sakai K, Tamura C, Amakasu D (1964) Tetrodotoxin. VII. On the structures of tetrodotoxin and its derivatives. Chem Pharm Bull 12:1357–1374 Tujula NA, Crocetti GR, Burke C, Thomas T, Holmstrom C, Kjelleberg S (2010) Variability and abundance of the epiphytic bacterial community associated with a green marine Ulvacean alga. ISME J 4:301–311 Uchiyama T, Miyazaki K (2009) Functional metagenomics for enzyme discovery: Challenges to efficient screening. Curr Opin Biotechnol 20:616–622 Unemoto T, Hayashi M, Hayashi M (1977) Na+-dependent activation of NADH oxidase in membrane fractions from halophilic Vibrio alginolyticus and V. costicolus. J Biochem 82:1389–1395 Villarreal-Gómez LJ, Soria-Mercado IE, Guerra-Rivas G, Ayala-Sánchez NE (2010) Antibacterial and anticancer activity of seaweeds and bacteria associated with their surface. Revista de Biología Marina y Oceanografía 45:267–275 Wang GY, Graziani E, Waters B, Pan W, Li X, McDermott J, Meurer G, Saxena G, Andersen RJ, Davies J (2000) Novel natural products from soil DNA libraries in a streptomycete host. Org Lett 2:2401– 2404 Wang S, Li X, Teuscher F, Li D, Diesel A, Ebel E, Proksch P, Wang B (2006) Chaetopyranin, a benzaldehyde derivative, and other related metabolites from Chaetomium globosum, an endophytic fungus derived from the marine red alga Polysiphonia urceolata. J Nat Prod 69:1622–1625 Ward DM, Weller R, Bateson MM (1990) 16S rRNA sequences reveal numerous uncultured microorganisms in a natural community. Nature 345:63–65 Waters AL, Hill RT, Place AR, Hamann MT (2010) The expanding role of marine microbes in pharmaceutical development. Curr Opin Biotechnol 21:780–786 Webster NS, Cobb RE, Negri AP (2008) Temperature thresholds for bacterial symbiosis with a sponge. ISME J 2:830–842 White JF Jr, Torres MS (2010) Is plant endophyte-mediated defensive mutualism the result of oxidative stress protection? Physiol Plant 138:440–446
Appl Microbiol Biotechnol (2015) 99:1571–1586 Wiese J, Thiel V, Nagel K, Staufenberger T, Imhoff JF (2009) Diversity of antibiotic active bacteria associated with the brown alga Laminaria saccharina from the Baltic Sea. Mar Biotechnol 11:287–300 Woodward RB (1964) The structure of tetrodotoxin. Pure Appl Chem 9: 49–74 Yasumoto T, Yasumura D, Yotsu M, Michishita T, Endo A, Kotaki Y (1986) Bacterial production of tetrodotoxin and anhydrotetrodotoxin. Agric Biol Chem 50:793–795 Yokoo A (1950) Chemical studies on pufferfish toxin (3)—Separation of spheroidine. Nippon Kagaku Zasshi 71:590–592 Yoshikawa K, Takadera T, Adachi K, Nishijima M, Sano H (1997) Korormicin, a novel antibiotic specifically active against marine Gram-negative bacteria, produced by a marine bacterium. J Antibiot 50:949–953 Yoshikawa K, Nakayama Y, Hayashi M, Unemoto T, Mochida K (1999) Korormicin, an antibiotic specific for gram-negative marine bacteria, strongly inhibits the respiratory chain-linked Na+-translocating NADH: Quinone reductase from the marine Vibrio alginolyticus. J Antibiot 52:182–185 Yoshikawa K, Adachi K, Nishida F, Mochida K (2003) Planar structure and antibacterial activity of korormicin derivatives isolated from Pseudoalteromonas sp. F-420. J Antibiot 56:866–870 Yung PY, Burke C, Lewis M, Kjelleberg S, Thomas T (2011) Novel antibacterial proteins from the microbial communities associated with the sponge Cymbastela concentrica and the green alga Ulva australis. Appl Environ Microbiol 77:1512–1515 Zhang Y, Li XM, Wang BG (2007) Nigerasperones A~C; new monomeric and dimeric naphto-γ-pyrones from a marine alga-derived endophytic fungus Aspergillus niger EN-13. J Antibiot 60:204–210 Zhang Y, Li XM, Feng Y, Wang BG (2010) Phenethyl-α-pyrone derivatives and cyclodipeptides from a marine algous endophytic fungus Aspergillus niger EN-13. Nat Prod Res 24:1036–1043 Zhu TJ, Du L, Hao PF, Lin ZJ, Gu QQ (2009) Citrinal A, a novel tricyclic derivative of citrinin, from an algicolous fungus Penicillium sp. i-11. Chin Chem Lett 20:917–920 Zuccaro A, Mitchell JI (2005) Fungal communities of seaweeds. In: Dighton J, White JF Jr, Oudemans P (eds) The fungal community. CRC Press, New York, pp 533–579 Zuccaro A, Schulz B, Mitchell JI (2003) Molecular detection of ascomycetes associated with Fucus serratus. Mycol Res 107:1451–1466 Zuccaro A, Schoch CL, Spatafora JW, Kohlmeyer J, Draeger S, Mitchell JI (2008) Detection and identification of fungi intimately associated with the brown seaweed Fucus serratus. Appl Environ Microbiol 74:931–941
