title: Extraction, characterization and in vitro antioxidant activity of polysaccharides from black soybean.
abstract: Optimization of extraction conditions, preliminary characterization and in vitro antioxidant activity of polysaccharides from black soybean (BSPS) were investigated. The results of Box-Behnken design showed that the optimal extraction conditions for BSPS were as follows: ratio of water to material of 20 ml/g, extraction time of 6.4h and extraction temperature of 92 °C, with a corresponding yield of 2.56%. The crude BSPS were further fractionated on DEAE-52 and Sepharose CL-4B chromatography to afford three purified fractions (BSPS-1, BSPS-2 and BSPS-3). Chemical analysis showed that the three purified fractions were mainly composed of carbohydrate and uronic acid. In addition, BSPS-1 was composed of arabinose, rhamnose, galactose, glucose and mannose in the molar ratio of 1.79:1.00:2.59:26.54:1.01. BSPS-2 was composed of arabinose, rhamnose, xylose, galactose and mannose in the molar ratio of 8.10:4.80:9.15:13.38:1.00. BSPS-3 was composed of arabinose, rhamnose, galactose and mannose in the molar ratio of 16.80:3.60:33.66:1.00. The results of Fourier transform-infrared spectroscopy further confirmed the characteristic polysaccharide structures of the three purified fractions. Moreover, antioxidant assays showed crude BSPS and its purified fractions had potential superoxide anion and DPPH radical scavenging activities, and their antioxidant activity decreased in the order of crude BSPS > BSPS-3 > BSPS-2 > BSPS-1.
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China. Electronic address: junliu@yzu.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors.forename: Xiao-yuan
authors.initials: XY
authors.lastname: Wen
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors.forename: Xue-qing
authors.initials: XQ
authors.lastname: Zhang
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors.forename: Hui-min
authors.initials: HM
authors.lastname: Pu
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Kan
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors.forename: Chang-hai
authors.initials: CH
authors.lastname: Jin
mesh_terms: D000704:Analysis of Variance; D000975:Antioxidants / Q000494:pharmacology*; D001713:Biphenyl Compounds / Q000737:chemistry; D002849:Chromatography, Gas; D016166:Free Radical Scavengers / Q000494:pharmacology; D010851:Picrates / Q000737:chemistry; D011134:Polysaccharides / Q000302:isolation & purification* / Q000494:pharmacology*; D013025:Glycine max / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013481:Superoxides / Q000737:chemistry; D013696:Temperature; D013997:Time Factors; D014867:Water
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D010851:Picrates; D011134:Polysaccharides; D014867:Water; D013481:Superoxides; C004931:1,1-diphenyl-2-picrylhydrazyl
keywords: Antioxidant activity; Black soybean; Characterization; Polysaccharides