title: Antioxidant activities and phenolics of fermented Bletilla formosana with eight plant pathogen fungi.
abstract: The tubers of Bletilla formosana were fermented with eight plant pathogen fungi, respectively, and antioxidant activities and total phenolic content (TPC) of the crude extracts of fermented products and non-fermented products were investigated. The antioxidant activities were evaluated in three different test systems [DPPH, ABTS radical-scavenging activity, and ferric reducing-antioxidant power (FRAP)]. It was found that the extract of Helminthosporium maydis fermented B. formosana (FBF) possessed the highest TPC and exhibited a significant antioxidant activity compared with non-fermented product and other fermented products. Correlation analysis between antioxidant activities and TPC was also investigated. The good correlation between antioxidant activities and TPC revealed that the phenolic compounds might be the major contributors for the high antioxidant activities of the fermented B. formosana. Two phenolic compounds, curvularin and dehydrocurvularin, were isolated from H. maydis FBF, which had never been reported from plant of orchidaceae or H. maydis. Curvularin exhibited significant antioxidant activities, and was also present at a high concentration (0.373 mg/mg extract sample), implying an important role for the antioxidant activity of H. maydis FBF. This study suggested that proper fermentation processing could improve TPC and antioxidant activities of B. formosana.
authors.affiliation: Key Laboratory of Medicinal Chemistry for Nature Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China.
authors.forename: Jianwei
authors.initials: J
authors.lastname: Dong
authors.affiliation: Yunnan Institute of Microbiology, Kunming 650091, China.
authors.forename: Lixing
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Medicinal Chemistry for Nature Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China.
authors.forename: Le
authors.initials: L
authors.lastname: Cai
authors.affiliation: Key Laboratory of Medicinal Chemistry for Nature Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China.
authors.forename: Haixian
authors.initials: H
authors.lastname: Fang
authors.affiliation: Key Laboratory of Medicinal Chemistry for Nature Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China.
authors.forename: Xiuhua
authors.initials: X
authors.lastname: Chen
authors.affiliation: Key Laboratory of Medicinal Chemistry for Nature Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China. Electronic address: ztding@ynu.edu.cn.
authors.forename: Zhongtao
authors.initials: Z
authors.lastname: Ding
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification; D052160:Benzothiazoles / Q000037:antagonists & inhibitors; D001713:Biphenyl Compounds / Q000037:antagonists & inhibitors; D005285:Fermentation; D006375:Helminthosporium / Q000502:physiology*; D029595:Orchidaceae / Q000737:chemistry* / Q000382:microbiology; D010084:Oxidation-Reduction; D010636:Phenols / Q000737:chemistry* / Q000302:isolation & purification; D010851:Picrates / Q000037:antagonists & inhibitors; D010936:Plant Extracts / Q000737:chemistry; D035281:Plant Tubers / Q000737:chemistry / Q000382:microbiology; D013451:Sulfonic Acids / Q000037:antagonists & inhibitors; D015025:Zearalenone / Q000031:analogs & derivatives / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D000975:Antioxidants; D052160:Benzothiazoles; D001713:Biphenyl Compounds; D010636:Phenols; D010851:Picrates; D010936:Plant Extracts; D013451:Sulfonic Acids; C013914:dehydrocurvularin; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D015025:Zearalenone; C004931:1,1-diphenyl-2-picrylhydrazyl; C013455:curvularin
keywords: Antioxidant activity; Bletilla formosana; Curvulari; Fermentation; Helminthosporium maydis; Phenolics; Plant pathogen fungus