A new natural mycotoxin was isolated from the fermentation broth of Trichoderma sp. Jing-8 and the structure was determined as alternariol 1'-hydroxy-9-methyl ether (1), together with twelve known compounds. The structures were elucidated on the basis of their 1D, 2D NMR spectra and mass spectrometric data. Compounds 1, 8 and 9 indicated inhibitions against germination of the seeds of cabbage with MICs < 3 μg/mL. The compound 1 showed the antibacterial activity against Bacillus subtilis and Staphylococcus aureus with MICs at 64 μg/mL. Compound 1 and 3 showed significant DPPH radical-scavenging activities with IC at 12 μg/mL, respectively. The OH at C-1' in compound 1 decreased the cytotoxicity of these mycotoxins. A primary structure-activity relationship about the alternariol derivatives was discussed. Compounds 2-7 and 8 were the first time to be isolated from the Trichoderma.

Two new oxidation products-related aureonitol and cytochalasan were isolated from Chaetomium globosum fermented in Chinese yam (Dioscorea opposita) and determined as 10,11-dihydroxyl- aureonitol (1) and yamchaetoglobosin A (2). Compound 2 indicated significant inhibitory effect on nitric oxide production in LPS-activated macrophages, anti-acetylcholinesterase activity with the inhibition ratios of 92.5, 38.2% at 50 μM, and cytotoxicity to HL-60, A-549, SMMC-7721, MCF-7 and SW480 with the range of inhibition ratio at 51-96% for a concentration of 40 μM. Compounds 1, 2 showed weak anticoagulant activity with PT at 16.8 s. Few work was reported on the anti-acetylcholinesterase, and anticoagulant activities of aureonitol, and cytochalasan derivatives. The preliminary structure-activity relationship stated that the oxidation ring-opening in yamchaetoglobosin A can retain the inhibitory effect against NO production and tumor cell.

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Five new benzopyran derivatives (2-6) and a new natural product (1) were isolated from endophytic Daldinia eschscholzii in Dendrobium chrysotoxum and determined as (R)-2,3-dihydro-2,5-dihydroxy-2-methylchromen-4-one (1), (2R, 4S)-2,3-dihydro-2-methyl-benzopyran-4,5-diol (2), (R)-3-methoxyl-1-(2,6-dihydroxy phenyl)-butan-1-one (3), 7-O-α-d-ribosyl-5-hydroxy-2-methyl-4H-chromen-4-one (4), 7-O-α-d-ribosyl-2,3-dihydro-5-hydroxy-2-methyl-chromen-4-one (5), daldinium A (6). These compounds were evaluated for their antimicrobial activity, anti-acetylcholinesterase, nitric oxide inhibition, anticoagulant, photodynamic antimicrobial activities and glucose uptake of adipocytes. Some compounds showed photoactive antimicrobial activities and glucose uptake stimulating activities.

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