New bioactive compounds from aquatic endophyte <i>Chaetomium globosum</i>

<p>Two new oxidation products-related aureonitol and cytochalasan were isolated from <i>Chaetomium globosum</i> fermented in Chinese yam (<i>Dioscorea opposita</i>) and determined as 10,11-dihydroxyl- aureonitol (<b>1</b>) and yamchaetoglobosin A (<b>2</b>). Compound <b>2</b> 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 <b>1</b>, <b>2</b> 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.</p

Benzopyran derivatives from endophytic <i>Daldinia eschscholzii</i> JC-15 in <i>Dendrobium chrysotoxum</i> and their bioactivities

<p>Five new benzopyran derivatives (<b>2</b>–<b>6</b>) and a new natural product (<b>1</b>) were isolated from endophytic <i>Daldinia eschscholzii</i> in <i>Dendrobium chrysotoxum</i> and determined as (R)-2,3-dihydro-2,5-dihydroxy-2-methylchromen-4-one (<b>1</b>), (2R, 4S)-2,3-dihydro-2-methyl-benzopyran-4,5-diol (<b>2</b>), (R)-3-methoxyl-1-(2,6-dihydroxy phenyl)-butan-1-one (<b>3</b>), 7-O-α-d-ribosyl-5-hydroxy-2-methyl-4H-chromen-4-one (<b>4</b>), 7-O-α-d-ribosyl-2,3-dihydro-5-hydroxy-2-methyl-chromen-4-one (<b>5</b>), daldinium A (<b>6</b>). 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.</p