Secondary metabolites from a peanut-associated fungus Aspergillus niger IMBC-NMTP01 with cytotoxic, anti-inflammatory, and antimicrobial activities.

Chemical investigation of a peanut-associated fungal strain Aspergillus niger IMBC-NMTP01 resulted in isolation and identification of 14 secondary metabolites, including two new, epi -aspergillusol ( 1 ) and aspernigin ( 3 ), and 12 known compounds: pyrophen ( 2 ), 2-(hydroxyimino)-3-(4-hydroxyphenyl)propanoic acid ( 4 ), aspergillusol A ( 5 ), rubrofusarin B ( 6 ), nigerasperone A ( 7 ), fonsecin ( 8 ), TMC-256C1 ( 9 ), pyranonigrin A ( 10 ), orlandin ( 11 ), nigerasperone C ( 12 ), asperpyrone A ( 13 ), and 5-(hydroxymethyl)-2-furancarboxylic acid ( 14 ). Compounds 9 , 12-14 showed cytotoxicity toward all six human cancer cell lines, including HepG2, KB, HL-60, MCF-7, SK-Mel2, and LNCaP, with IC ₅₀ values ranging from 8.4 to 84.5 µM, compounds 3-5 were cytotoxic against five cancer cell lines except HepG2, whereas 1 exhibited cytotoxicity toward HepG2, KB, and MCF-7 cells. All of the compounds, except 2 and 13 , inhibited NO overproduction in LPS-induced RAW264.7 cells. In addition, all of the compounds displayed antimicrobial effects against Enterococcus faecalis , whereas 13 compounds, except 10 , significantly inhibited the growth of the yeast Candida albican s.