title: Dibenzo-α-pyrones from the endophytic fungus Alternaria sp. Samif01: isolation, structure elucidation, and their antibacterial and antioxidant activities.
abstract: The EtOAc extract of the liquid fermentation of Alternaria sp. Samif01, an endophytic fungus obtained from Salvia miltiorrhiza Bunge, showed antibacterial activity against several tested bacterial pathogens. Fractionation of this extract led to the isolation of seven dibenzo-α-pyrones (1-7), including one new compound, 2-acetoxy-2-epi-altenuene (1) and one new natural product, 3-epi-dihydroaltenuene A (2). The structures of the new metabolites were elucidated by comprehensive analysis of the spectroscopic data including (1D, 2D) NMR and HRESIMS, while the absolute configuration of 1 was determined by TDDFT-ECD computation. Altenuisol (5), 4-hydroxyalternariol-9-methyl ether (6), and alternariol (7) showed inhibitory activities against the tested bacteria with minimum inhibitory concentration values in the range of 86.7-364.7 μM. A preliminary structure-antibacterial activity relationship was discussed. In addition, compounds 2, 5 and 6 displayed promising antioxidant effects using DPPH and hydroxyl radical assays. The cytotoxicity of the isolated compounds was evaluated as well.
authors.affiliation: a Department of Plant Pathology, College of Plant Protection , China Agricultural University , Beijing , China.|b National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology , Chinese Academy of Sciences , Beijing , China.
authors.forename: Jin
authors.initials: J
authors.lastname: Tian
authors.affiliation: a Department of Plant Pathology, College of Plant Protection , China Agricultural University , Beijing , China.
authors.forename: Linyun
authors.initials: L
authors.lastname: Fu
authors.affiliation: a Department of Plant Pathology, College of Plant Protection , China Agricultural University , Beijing , China.
authors.forename: Zihao
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: a Department of Plant Pathology, College of Plant Protection , China Agricultural University , Beijing , China.
authors.forename: Xuejiao
authors.initials: X
authors.lastname: Dong
authors.affiliation: a Department of Plant Pathology, College of Plant Protection , China Agricultural University , Beijing , China.
authors.forename: Dan
authors.initials: D
authors.lastname: Xu
authors.affiliation: a Department of Plant Pathology, College of Plant Protection , China Agricultural University , Beijing , China.
authors.forename: Ziling
authors.initials: Z
authors.lastname: Mao
authors.affiliation: c Institute of Food Science and Technology , Chinese Academy of Agricultural Sciences , Beijing , China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: a Department of Plant Pathology, College of Plant Protection , China Agricultural University , Beijing , China.
authors.forename: Daowan
authors.initials: D
authors.lastname: Lai
authors.affiliation: a Department of Plant Pathology, College of Plant Protection , China Agricultural University , Beijing , China.
authors.forename: Ligang
authors.initials: L
authors.lastname: Zhou
mesh_terms: D000528:Alternaria / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D007783:Lactones / Q000494:pharmacology; D011753:Pyrones / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; D000975:Antioxidants; D007783:Lactones; D011753:Pyrones; C005197:alternariol
keywords: Alternaria sp.; Endophytic fungus; Salvia miltiorrhiza; antibacterial; antioxidant; dibenzo-α-pyrones