title: Phenolic composition and antioxidant activity in seed coats of 60 Chinese black soybean (Glycine max L. Merr.) varieties.
abstract: Phenolics in black soybean seed coat (BSSC) are considered to be responsible for the health benefits of black soybean. BSSCs of 60 Chinese varieties were examined for phenolic contents, anthocyanin profiles, and antioxidant activity. Total phenolic and condensed tannin contents ranged from 512.2 to 6057.9 mg gallic acid equivalents/100 g and from 137.2 to 1741.1 mg (+)-catechin equivalents/100 g, respectively. Six anthocyanins (delphinidin-3-glucoside, cyanidin-3-galactoside, cyanidin-3-glucoside, petunidin-3-glucoside, peonidin-3-glucoside, and malvidin-3-glucoside) were detected by HPLC. Total anthocyanin contents (TAC) were from 98.8 to 2132.5 mg/100 g, and cyanidin-3-glucoside was the most abundant anthocyanin in all varieties, with a distribution of 48.8-94.1% of TAC. Antioxidant properties detected by DPPH, FRAP, and ORAC methods all showed wide variations ranging from 4.8 to 65.3 μg/100 mL (expressed as EC(50)), from 17.5 to 105.8 units/g, and from 42.5 to 1834.6 μmol Trolox equivalent/g, respectively. Sixty varieties were classified into four groups by hierarchical clustering analysis, and group 4 consisting of nine varieties had the highest phytochemicals content and antioxidant activity.
authors.affiliation: Key Laboratory of Functional Food Research, Ministry of Agriculture, Bio-Technical Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510610, China.
authors.forename: Rui Fen
authors.initials: RF
authors.lastname: Zhang
authors.forename: Fang Xuan
authors.initials: FX
authors.lastname: Zhang
authors.forename: Ming Wei
authors.initials: MW
authors.lastname: Zhang
authors.forename: Zhen Cheng
authors.initials: ZC
authors.lastname: Wei
authors.forename: Chun Ying
authors.initials: CY
authors.lastname: Yang
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiao Jun
authors.initials: XJ
authors.lastname: Tang
authors.forename: Yuan Yuan
authors.initials: YY
authors.lastname: Deng
authors.forename: Jian Wei
authors.initials: JW
authors.lastname: Chi
mesh_terms: D000975:Antioxidants / Q000737:chemistry*; D002681:China; D006801:Humans; D010636:Phenols / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D012639:Seeds / Q000737:chemistry; D013025:Glycine max / Q000737:chemistry* / Q000145:classification
chemical_list: D000975:Antioxidants; D010636:Phenols; D010936:Plant Extracts