Bioactive compounds guided diversity of endophytic fungi from Baliospermum montanum and their potential extracellular enzymes.

Baliospermum montanum (Willd.) Muell. Arg, a medicinal plant distributed throughout India from Kashmir to peninsular-Indian region is extensively used to treat jaundice, asthma, and constipation. In the current study, 203 endophytic fungi representing twenty-nine species were isolated from tissues of B. montanum. The colonization and isolation rate of endophytes were higher in stem followed by seed, root, leaf and flower. The phytochemical analysis revealed 70% endophytic isolates showed alkaloids and flavonoids, 13% were positive for phenols, saponins and terpenoids. Further, these endophytes produced remarkable extracellular enzymes such as amylase, cellulase, phosphates, protease and lipase. The most promisive three endophytic fungi were identified by ITS region and secreted metabolites were identified by gas chromatography-mass spectrometry (GC-MS/MS). The GC-MS profile detected twenty-five bioactive compounds from ethyl acetate extracts. Among endophytic fungi, Trichoderma reesei isolated from flower exhibited nine bioactive compounds namely, 2-Cyclopentenone, 2-(4-chloroanilino)-4-piperidino, Oxime-methoxy-Phenyl, Methanamine N-hydroxy-N-methyl, Strychane, Cyclotetrasiloxane, Octamethyl and 1-Acetyl-20a-hydroxy-16-methylene. The endophyte, Aspergillus brasiliensis isolated from root and Fusarium oxysporum isolated from seed produced nine and seven bioactive compounds, respectively. Overall, a significant contribution of bioactive compounds was noticed from the diverse endophytic fungi associated with B. montanum and could be explored for development of novel drug with commercial values.

Combined Effects of Dissolved Nutrients and Oxygen on Plant Litter Decomposition and Associated Fungal Communities.

Aquatic ecosystems worldwide have been substantially altered by human activities, which often induce changes in multiple factors that can interact to produce complex effects. Here, we evaluated the combined effects of dissolved nutrients (nitrogen [N] and phosphorus [P]; three levels: concentration found in oligotrophic streams in the Cerrado biome, 10× and 100× enriched) and oxygen (O2; three levels: hypoxic [4% O2], depleted [55% O2], and saturated [96% O2]) on plant litter decomposition and associated fungal decomposers in laboratory microcosms simulating stream conditions under distinct scenarios of water quality deterioration. Senescent leaves of Maprounea guianensis were incubated for 10 days in an oligotrophic Cerrado stream to allow microbial colonization and subsequently incubated in microcosms for 21 days. Leaves lost 1.1-3.0% of their initial mass after 21 days, and this was not affected either by nutrients or oxygen levels. When considering simultaneous changes in nutrients and oxygen concentrations, simulating increased human pressure, fungal biomass accumulation, and sporulation rates were generally inhibited. Aquatic hyphomycete community structure was also affected by changes in nutrients and oxygen availability, with stronger effects found in hypoxic treatments than in depleted or saturated oxygen treatments. This study showed that the effects of simultaneous changes in the availability of dissolved nutrients and oxygen in aquatic environments can influence the activity and composition of fungal communities, although these effects were not translated into changes in litter decomposition rates.

3-Arylisoindolinone and sesquiterpene derivatives from the mangrove endophytic fungi Aspergillus versicolor SYSU-SKS025.

A pair of 3-arylisoindolinone enantiomers: (+)-asperglactam A (1), (-)-asperglactam A (1) and a pair of nor-bisabolane enantiomers: (+)-1-hydroxyboivinianic acid (2), (-)-1-hydroxyboivinianic acid (2), along with seven known compounds (3-8) were obtained from the mangrove endophytic fungus Aspergillus versicolor SYSU-SKS025. Their structures were determined on the basis of HRESIMS and NMR spectroscopic data, and X-ray diffraction. (+)-Asperglactam A (1) and (-)-asperglactam A (1) are the first optically pure examples in the 3-arylisoindolinone family, which are rarely found in natural sources. All isolated compounds were evaluated for α-glucosidase inhibitory activity. The enantiomers of 1-3 showed moderate inhibitory activity against α-glucosidase with IC50 values ranging from 50 to 190µM. Compound 7 exhibited significant inhibitory activity against α-glucosidase with IC50 value of 7.5µM. In addition, compound 7 was found to inhibit nitric oxide production in RAW 264.7 macrophages with IC50 value of 12.5µM.

Cytotoxic polyphenols from the fungus Penicillium expansum 091 006 endogenous with the mangrove plant Excoecaria agallocha.

As part of our ongoing chemical investigation of biologically active metabolites from marine-derived fungi, four new polyphenols containing both phenolic bisabolane and diphenyl ether units, expansols C-F (1-4), and one new diphenyl ether derivative, 3-O-methyldiorcinol (5), as well as twelve known compounds (6-17), were isolated from Penicillium expansum 091006 endogenous with the mangrove plant Excoecaria agallocha (Euphorbiaceae). The structures of the new metabolites were determined on the basis of NMR and mass spectroscopy. Among them, expansols C (1) and E (3) exhibited weak cytotoxicity against the HL-60 cell lines with IC50 values of 18.2 and 20.8 µM, respectively. The results showed that diphenyl ether substituted phenolic bisabolanes with a Δ7 double bond in the side chain are slightly less cytotoxic to HL-60 cell lines than the 7-OH or 7-OCH3 derivatives.

[Comparative studies on the fatty acids contained in four species of medicinal plants from family Euphorbiaceae and their endophytic fungi].

OBJECTIVE: The relation of four species of medicinal plants from family Euphorbiaceae and their endophytic fungi was studied to find the source of active substances for developing new pharmaceutical resources. METHOD: The main fatty acids contained in Sapium sebiferum, Euphorbia pekinensis, Euphorbia helioscopia, Bischofia polycarpam and their 28 strains of endophytic fungi were compared and analysed by GC. RESULT: The main fatty acids of the plants are: alpha-linolenic acid, palmitic acid, linolenic acid and oleic acid. Linolenic acid, palmitic acid and oleic acid are the main fatty acids of the endophytic fungi. CONCLUSION: The fatty acids could be produced by the endophytic fungi, which could be used as a factor for identification. There are great differences at the contents of alpha-linolenic acid between the plants and their endophytic fungi, which were suggested to be related with the nutrition absorption and the relationship between the endophytes and the host plant.