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Two new 3,8-cyclized cembranoids, briarenols O (1) and P (2), featuring with briarane carbon skeleton have been isolated from a cultured octocoral Briareum excavatum. The structures of 1 and 2 were established by spectroscopic methods and 1 was found to be a rare 2-ketobriarane. Briarane 1 enhanced the generation of inducible nitric oxide synthase (iNOS) from RAW 264.7 stimulated by lipopolysaccharides (LPS).

Located in tropical and subtropical region, Taiwan is an island with high algal species diversity. In this study, a number of fungal strains were isolated from marine macroalgae collected from northeastern intertidal zone of Taiwan. Preliminary anti-inflammatory screening has shown that the methanolic extracts of solid fermented products of the red alga Mastophora rosea-derived fungal strain Acremonium sp. NTU492 exhibited significant bioactivity. In an attempt to disclose the active principles from this fungal strain, a series of separation and purification was thus undertaken, which has led to the isolation and characterization of seven compounds including four new peptides, namely acrepeptins A-D (1-4), along with previously reported destruxin B (5), guangomide A (6), and guangomide B (7). Their structures were elucidated by spectroscopic analysis and compared with literatures. Of these, acrepeptins A (1) and C (3) showed markedly inhibitory activities on nitric oxide production in lipopolysaccharide-activated microglial BV-2 cells with IC

Marine fungi are regarded as an under-explored source of structurally interesting and bioactive natural products with the potential to provide attractive lead compounds for drug discovery. In this study, several fungal strains were isolated from marine algae collected from the northeastern coast of Taiwan. In the preliminary antimicrobial screening against bacteria and fungi, the ethyl acetate extract of the fermented products of Aspergillus terreus NTU243 derived from a green alga Ulva lactuca was found to exhibit significant antimicrobial activities. Therefore, bioassay-guided separations of the active principle from liquid and solid fermented products of A. terreus NTU243 were undertaken, which resulted in the isolation and purification of 16 compounds. Their structures were elucidated by spectroscopic analysis to be four previously undescribed aspulvinones S-V as well as twelve known compounds. All the isolates were assessed for anti-inflammatory activity by measuring the amount of nitric oxide (NO) production in lipopolysaccharide (LPS)-induced BV-2 cells, and aspulvinone V, butyrolactone I, and (+)-terrein inhibited 45.0%, 34.5%, and 49.2% of NO production, respectively, at 10 μM concentration. Additionally, zymography showed that the conditioned medium of THP-1 cells post-LPS challenged significantly enhanced matrix metalloproteinase (MMP)-9-mediated gelatinolysis, and pretreatment with aspulvinones U and V significantly attenuated MMP-9-mediated gelatinolysis by 56.0% and 67.8%, separately.

Five 2-acetoxybriaranes, including two known analogues, excavatolides B (1), E (2), along with three new metabolites, briaviolides V–X (3–5), have been obtained from the octocoral Briareum violaceum. The absolute configurations of 1 and 2 were determined by X-ray analysis for the first time and the structures of 3–5 were established by spectroscopic methods. Bioactivity study showed that briarane 3 decreased the release of elastase from human neutrophils.

A known briarane, brianthein W (1), along with four new hydroperoxybriaranes, briaviolides R–U (2–5), have been obtained from the octocoral Briareum violaceum. The absolute configuration of 1 was determined by X-ray analysis for the first time and the structures of briaranes 2–5 were established by spectroscopic methods. Bioactivity study showed that briarane 3 decreased the production of superoxide anions from human neutrophils.

Fungal endophytes have been found to exist in many plant species and appear to be important to their plant hosts. However, the diversity and biological activities of these fungi remain largely unknown. Zanthoxylum simulans Hance, a popular natural spice and medicinal plant, commonly known as Szechuan pepper or Chinese-pepper, grows on Kinmen Island, Taiwan. In this study, leaf and stem samples of Z. simulans, collected in summer and winter, were screened for antimicrobial and anti-inflammatory metabolite-producing endophytic fungi. A total of 113 endophytic strains were isolated and cultured from Z. simulans, among which 23 were found to possess antimicrobial activity, belonging to six fungal genera: Penicillium (26.09%, 6), Colletotrichum (21.74%, 5), Diaporthe (21.74%, 5), Daldinia (17.39%, 4), Alternaria (8.70%, 2), and Didymella (4.34%, 1). We also found that the number of species with antimicrobial activity and their compositions differed between summer and winter. Our study demonstrated that Z. simulans might contain large and diverse communities of endophytic fungi, and its community composition varies seasonally. In addition, fungal endophytes produce antimicrobial agents, which may protect their hosts against pathogens and could be a potential source of natural antibiotics.

A high diversity of culturable foliar endophytic fungi is known from various mangrove plants, and the core taxa include species from Colletotrichum, Pestalotiopsis, Phoma, Phomopsis, Sporomiella, among others. Since a small fraction of fungi is able to grow in culture, this study investigated the diversity of fungi associated with leaves of Acanthus ilicifolius var. xiamenensis using both isolation and metabarcoding approaches. A total of 203 isolates were cultured from surface-sterilized leaves, representing 47 different fungal species: 30 species from the winter samples (104 isolates), and 26 species from the summer samples (99 isolates). Ascomycota was dominant in both types of leaf samples, while Basidiomycota was isolated only from the summer samples. Drechslera dematioidea (10.58%, percentage of occurrence), Colletotrichum sp. 3 (7.69%) and Alternaria sp. (7.69%) were dominant in the winter samples; Fusarium oxysporum (13.13%), Diaporthe endophytica (10.10%) and Colletotrichum sp. 1 (9.09%) in the summer samples. Overall, Corynespora cassiicola (6.90%), F. oxysporum (6.40%) and Guignardia sp. (6.40%) had the highest overall percentage of occurrence. In the metabarcoding analysis, a total of 111 operational taxonomic units (OTUs) were identified from 17 leaf samples: 96 OTUs from the winter and 70 OTUs from the summer samples. Sequences belonging to Ascomycota and Basidiomycota were detected in both samples but the former phylum was dominant over the latter. Based on read abundance, taxa having the highest percentage of occurrence included Alternaria sp. (3.46%), Cladosporium delicatulum (2.56%) and Pyrenochaetopsis leptospora (1.41%) in the winter leaves, and Aureobasidium sp. (10.72%), Cladosporium sp. (7.90%), C. delicatulum (3.45%) and Hortaea werneckii (3.21%) in the summer leaves. These latter four species also had the highest overall percentage of occurrence. Combining the results from both methods, a high diversity of fungi (at least 110 species) was found associated with leaves of A. ilicifolius var. xiamenensis. Many of the fungi identified were plant pathogens and may eventually cause diseases in the host.

Background Acanthus ilicifolius var. xiamenensis (Acanthaceae) is an old world mangrove species and has long been used as a folk remedy for treating various ailments in traditional medicine. The nature source of A. ilicifolius var. xiamenensis is now in short supply because of the urban development and habitat destruction. To better utilize this resource, biodiversity and bioactivity of endophytic fungi isolated from A. ilicifolius var. xiamenensis were investigated. Results A total of 168 fungal isolates were cultured from leaves and stems of the mangrove plant collected in January (winter) and July (summer) 2014 at Kinmen County, Taiwan. Spent culture extract of 28 isolates were found to have bioactivities against one of the following pathogenic microorganisms: the bacteria Bacillus subtilis, Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) and the fungi Candida albicans and Cryptococcus neoformans. These positive extracts were mostly active against the Gram-positive bacteria and C. albicans. Corynespora cassiicola NTOU4889 and Xylaria sp. NTOU4900 inhibited growth of all 3 test bacteria whereas Phellinus noxius NTOU4917 inhibited both test fungi. A further anti-inflammatory study of culture extracts of these 28 isolates revealed that extracts with a high iNOS inhibition caused a low viability of cells, and those with a low iNOS inhibition had a high cell viability. Three extracts showed low cytotoxicity (i.e. > 100% cell viability) and high iNOS inhibition (

The marine red alga Pterocladiella capillacea is an economic alga for the food industry in Taiwan, and its associated highly diversified fungi have not been investigated meticulously thus far. The EtOAc extract of the fermented broth of Chondrostereum sp. NTOU4196, a fungal strain isolated from P. capillacea, was found to exhibit significant nitric oxide (NO) production inhibitory activity in lipopolysaccharide-activated murine RAW 264.7 cells at a concentration of 100 μg/mL in the preliminary screening. Therefore, separation of the active principles from the fermented broths was performed, and that has led to the isolation of eight new 5,5,5-tricyclic hirsutane-type sesquiterpenes, namely, chondroterpenes A-H (1-8), together with seven known analogues. They were identified by analyses of spectroscopic data and comparison with literature values. Among the new isolates, chondroterpene A (1) exhibited more significant NO production inhibitory activity in murine BV-2 microglial cells, and of all the isolated compounds, hirsutanol A (9) exerted limited cytotoxic effects and the most potent inhibitory activity on NO production.

Shewanella sp. NTOU1 was able to decolorize a range of anthraquinone dyes [Reactive Blue 4 (RB4), Reactive Blue 19 (RB19), Mordant Red 11 (MR11), Disperse Red 15 (DR15), and Disperse Blue 3 (DB3)] under anaerobic conditions. By supplementing the medium with formate and ferric citrate as the electron donor and acceptor, respectively and cultivating it under the optimum pH (8–9) and temperature (45°C), this strain could decolorize these dyes (1,000 mg/L) at the initial color removal rates of 15–126 mg/L/h and the rates among them were RB19 > RB4 > DB3 > DR15 > MR11. The extent of color removal was in the range of 90–98% for RB19, 86–96% for RB4, 39–41% for MR11, 69–82% for DR15, and 89–91% for DB3. Based on the decolorization products detected by means of GC/MS analyses, probable pathways for the decolorization of these dyes by this strain were proposed.

The discovery of new natural products from fungi isolated from the marine environment has increased dramatically over the last few decades, leading to the identification of over 1000 new metabolites. However, most of the reported marine-derived species appear to be terrestrial in origin yet at the same time, facultatively halo- or osmotolerant. An unanswered question regarding the apparent chemical productivity of marine-derived fungi is whether the common practice of fermenting strains in seawater contributes to enhanced secondary metabolism? To answer this question, a terrestrial isolate of Aspergillus aculeatus was fermented in osmotic and saline stress conditions in parallel across multiple sites. The ex-type strain of A. aculeatus was obtained from three different culture collections. Site-to-site variations in metabolite expression were observed, suggesting that subculturing of the same strain and subtle variations in experimental protocols can have pronounced effects upon metabolite expression. Replicated experiments at individual sites indicated that secondary metabolite production was divergent between osmotic and saline treatments. Titers of some metabolites increased or decreased in response to increasing osmolite (salt or glycerol) concentrations. Furthermore, in some cases, the expression of some secondary metabolites in relation to osmotic and saline stress was attributed to specific sources of the ex-type strains.

It was found in this study that while addition of the predicted intermediate product benzoate did not, addition of cyclohex-1-ene or cyclohexane carboxylate did inhibit the biotransformation of o -phthalate in sulfate-reducing o -phthalate-adapted sediment slurries under a CO 2 /H 2 atmosphere. Biotransformation rates of benzoate were slightly higher than those of o -phthalate in sediment slurries amended with o -phthalate plus benzoate. By using the most probable number (MPN) method to determine the number of o -phthalate transformers, similar growth dynamics of o -phthalate transformers were observed in sediment slurries amended with or without benzoate. The number of benzoate transformers (1 × 10 9 cells g −1 of sediment) remained the same in sediment slurries repeatedly amended with a mixture of o -phthalate and benzoate after their transformation. o -Phthalate transformers decreased about three orders (1 × 10 9 to 1 × 10 6 cells g −1 of sediment) of magnitude after biotransformation of o -phthalate, and remained at the low number thereafter until re-amendment with o -phthalate. o -Phthalate transformers increased to 1 × 10 8 cells g −1 of sediment just prior to the onset of biotransformation of the o -phthalate.

Composition of the headspace gas affected the biotransformation pattern of toluic acid isomers in anoxic sediment slurries. Under an N2 atmosphere, o- and m-, and p-toluic acid (20-25 mg L(-1)) were biotransformed in 100 days, 77 days, and 148 days, respectively, with a lag period of 50 days, 49 days, and 50 days, respectively. Under a CO2 atmosphere, the same toluic acid isomers were biotransformed by the sediment microorganisms in 16-25 days without a lag period. CO2 thus increased the biotransformation rates. The presence of H2, on the other hand, decreased the biotransformation rates: in most cases, adding H2 gas (5% and 20% to the N2 and CO2 atmospheres, respectively) not only increased the lag period but also decreased the maximum biotransformation rates. These effects were especially noticeable for the N2 atmosphere. Under N2, the maximum biotransformation rates of the toluic acid isomers were in the order o-toluic acid > m-toluic acid > p-toluic acid. However, under CO2, the maximum biotransformation rates were reversed, i.e., p-toluic acid > m-toluic acid > o-toluic acid. The presence of the methanogen inhibitor bromoethanesulfonic acid (BESA) slowed the biotransformation rates of p-toluic acid, and this together with the population dynamics of the acetogenic bacteria in the sediment slurries, suggested that acetogenic bacteria were involved in the degradation pathway. However, their exact role remains unclear.