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A chemical study of the EtOAc extract of Nemania bipapillata (AT-05), an endophytic fungus isolated from the marine red alga Asparagopsis taxiformis - Falkenbergia stage, led to the isolation of five new botryane sesquiterpenes, including the diastereomeric pair (+)-(2R,4S,5R,8S)-(1) and (+)-(2R,4R,5R,8S)-4-deacetyl-5-hydroxy-botryenalol (2), (+)-(2R,4S,5R,8R)-4-deacetyl-botryenalol (3), one pair of diastereomeric botryane norsesquiterpenes bearing an unprecedented degraded carbon skeleton, (+)-(2R,4R,8R)-(4) and (+)-(2R,4S,8S)-(5), which were named nemenonediol A and nemenonediol B, respectively, in addition to the known 4β-acetoxy-9β,10β,15α-trihydroxyprobotrydial (6). Their structures were elucidated using 1D and 2D NMR, HRESIMS and comparison with literature data of similar known compounds. The absolute configurations of 2, 3 and 4 were deduced by comparison of experimental and calculated electronic circular dichroism (ECD) spectra, while those of 1 and 5 were assigned from vibrational circular dichroism (VCD) data. Compound 4 weakly inhibited acetylcholinesterase, whereas compound 1 inhibited both acetylcholinesterase and butyrylcholinesterase. Compounds 1, 3, 5 and 6 were tested against two carcinoma cell lines (MCF-7 and HCT-116), but showed no significant citotoxicity at tested concentrations (IC 50  > 50 µM).

In recent years, fungi have been shown to produce a plethora of new bioactive secondary metabolites of interest, as new lead structures for medicinal and other pharmacological applications. The present investigation was carried out to study the pharmacological properties of a potent and major bioactive compound: xylaranic acid, which was obtained from Xylaria primorskensis (X. primorskensis) terpenoids in terms of antibacterial activity, antioxidant potential against DPPH & H 2 O 2 radicals and anticancer activity against human lung cancer cells. Due to terpenoid nature, low water solubility and wretched bioavailability, its pharmacological use is limited. To overcome these drawbacks, a novel xylaranic acid silver nanoparticle system (AgNPs) is developed. In addition to improving its solubility and bioavailability, other advantageous pharmacological properties has been evaluated. Furthermore, enhanced anticancer activity of xylaranic acid and its AgNPs due to induced apoptosis were also confirmed by determining the expression levels of apoptosis regulatory genes p53, bcl-2 and caspase-3 via qRT PCR method. This is the first study developing the novel xylaranic acid silver nanoparticle system and enlightening its therapeutic significance with its improved physico-chemical properties and augmented bioactive potential.

Four new 12,8-Eudesmanolides (1-4) and one known compound 5 named 13-Hydroxy-3,7(11)-eudesmadien-12,8-olide, were isolated from a mangrove rhizosphere-derived fungus Eutypella sp. 1-15. Their structures with absolute stereochemistry were determined by the comprehensive spectroscopic data, experimental and calculated ECD analysis. Compound 1 exhibited potent anticancer activity against JEKO-1 and HepG2 with IC 50 values of 8.4 and 28.5 μM, respectively. Additionally, compound 1 also showed moderate antimicrobial activity.

Two new cyclopentapeptides, xylapeptide A (1) with an uncommon L-pipecolinic acid moiety, and xylapeptide B (2) having a common L-proline residue were identified from an associated fungus Xylaria sp. isolated from the Chinese medicinal plant Sophora tonkinensis. Their planar structures were elucidated by a comprehensive analysis of NMR and MS spectroscopic spectra. The absolute configurations were determined by Marfey's method and single-crystal X-ray diffraction (Cu Kα) analysis. Xylapeptide A (1) is the first example of cyclopentapeptide with L-Pip of terrestrial origin and showed strong antibacterial activity against Bacillus subtilis and B. cereus with MIC value of 12.5 μg/mL.

A strain of Hypoxylon submonticulosum was isolated as an endophyte from a surface-sterilized leaf of a cultivated raspberry (Rubus idaeus). The liquid culture extract displayed growth inhibition activity against Saccharomyces cerevisiae using a disc diffusion assay. The extract's major component was identified as a new natural product, trienylfuranol A (1S,2S,4R)-1-((1'E,3'E)-hexa-1',3',5'-trienyl)-tetrahydro-4-methylfuran-2-ol (1), by high-resolution LC-MS and 1D and 2D NMR spectroscopy. Two additional new metabolites, trienylfuranones A (2) and B (3), were isolated as minor components of the extract and their structure elucidation revealed that they were biosynthetically related to 1. Absolute stereochemical configurations of compounds 1-3 were confirmed by NOE NMR experiments and by the preparation of Mosher esters. Complete hydrogenation of 1 yielded tetrahydrofuran 7 that was used for stereochemical characterization and assessment of antifungal activity.

Three new phthalide derivatives (1-3) named 5-(3'-methyl-2'-butenyl)-2-hydroxy-3-methoxy-4-methylbenzoic acid (1), 5-(3'-carboxyl-3'-methyl-2E-allyloxy)-3-methoxy-4-methylphthalide (2) and 5-(3',3'-dimethylallyloxy)-2-methoxycarbonyl-3-methoxy-4-methylbenzoic acid (3) together with six known phthalide derivatives named 5-(3',3'-dimethylallyloxy)-3-methoxy-4-methylphthalide (4), zinnimidine (5), 5-(3',3'-dimethylallyloxy)-3-methoxy-4-methylphthalide (6), 5-(3',3'-dimethylallyloxy)-3-methoxy-4-methylphthalic acid (7), zinniol anhydride (8) and porriolide (9) were isolated from the liquid culture of the plant endophytic fungus Pestalotiopsis photiniae isolated from the Chinese Podocarpaceae plant Podocarpus macrophyllus. Their structures were elucidated by extensive spectroscopic analysis. Compounds 1-9 displayed significant antifungal activities against three plant pathogens.