title: Identification and Bioactivity of Compounds from the Mangrove Endophytic Fungus Alternaria sp.
abstract: Racemic new cyclohexenone and cyclopentenone derivatives, (±)-(4R*,5S*,6S*)-3-amino-4,5,6-trihydroxy-2-methoxy-5-methyl-2-cyclohexen-1-one (1) and (±)-(4S*,5S*)-2,4,5-trihydroxy-3-methoxy-4-methoxycarbonyl-5-methyl-2-cyclopenten-1-one (2), and two new xanthone derivatives 4-chloro-1,5-dihydroxy-3-hydroxymethyl-6-methoxycarbonyl-xanthen-9-one (3) and 2,8-dimethoxy-1,6-dimethoxycarbonyl-xanthen-9-one (4), along with one known compound, fischexanthone (5), were isolated from the culture of the mangrove endophytic fungus Alternaria sp. R6. The structures of these compounds were elucidated by analysis of their MS (Mass), one and two dimensional NMR (nuclear magnetic resonance) spectroscopic data. Compounds 1 and 2 exhibited potent ABTS [2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)] scavenging activities with EC50 values of 8.19 ± 0.15 and 16.09 ± 0.01 μM, respectively. In comparison to Triadimefon, compounds 2 and 3 exhibited inhibitory activities against Fusarium graminearum with minimal inhibitory concentration (MIC) values of 215.52 and 107.14 μM, respectively, and compound 3 exhibited antifungal activity against Calletotrichum musae with MIC value of 214.29 μM.
authors.affiliation: College of Materials and Energy (Formerly College of Science), South China Agricultural University, Guangzhou 510642, China. alanwongjh@sina.com.
authors.forename: Jinhua
authors.initials: J
authors.lastname: Wang
authors.affiliation: College of Materials and Energy (Formerly College of Science), South China Agricultural University, Guangzhou 510642, China. dwjzsu@scau.edu.cn.
authors.forename: Weijia
authors.initials: W
authors.lastname: Ding
authors.affiliation: College of Materials and Energy (Formerly College of Science), South China Agricultural University, Guangzhou 510642, China. wangruimin47@sina.cn.
authors.forename: Ruimin
authors.initials: R
authors.lastname: Wang
authors.affiliation: College of Materials and Energy (Formerly College of Science), South China Agricultural University, Guangzhou 510642, China. ohbilly@sina.com.
authors.forename: Yipeng
authors.initials: Y
authors.lastname: Du
authors.affiliation: College of Materials and Energy (Formerly College of Science), South China Agricultural University, Guangzhou 510642, China. LHLincredible@gmail.com.
authors.forename: Huanliang
authors.initials: H
authors.lastname: Liu
authors.affiliation: College of Materials and Energy (Formerly College of Science), South China Agricultural University, Guangzhou 510642, China. akongxuehua@sina.com.
authors.forename: Xuehua
authors.initials: X
authors.lastname: Kong
authors.affiliation: College of Materials and Energy (Formerly College of Science), South China Agricultural University, Guangzhou 510642, China. chunyuanli@scau.edu.cn.
authors.forename: Chunyuan
authors.initials: C
authors.lastname: Li
mesh_terms: D000528:Alternaria / Q000737:chemistry*; D000935:Antifungal Agents / Q000302:isolation & purification* / Q000494:pharmacology; D005670:Fusarium / Q000187:drug effects; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D031643:Myoporum / Q000382:microbiology; D020081:Phyllachorales / Q000187:drug effects
chemical_list: D000935:Antifungal Agents
keywords: Alternaria sp.; antimicrobial activity; antioxidant activity; cyclohexenone; cyclopentenone; secondary metabolites; xanthone