酶法制备的豆渣可溶性膳食纤维组成分析及其抗氧化性能研究

采用纤维素酶、α-淀粉酶酶解,乙醇分级沉淀法制备得到三种不同组分的豆渣可溶性膳食纤维（SDF-1、SDF-3、SDF-5）,并采用气相色谱法、红外光谱法、体外抗氧化法等对其成分及抗氧化活性进行研究。成分分析结果表明,SDF-1中含有的总糖和半乳糖醛酸含量均为最高,分别为53.44%和20.43%,而SDF-5中还原糖含量最高,为10.56%;SDF-1由Ara、Man、Glu和Gal所组成,摩尔比为1.21∶1.60∶4.90∶1.33;SDF-3与SDF-5均由Rha、Ara、Xyl、Man、Glu和Gal所组成,摩尔比分别为2.00∶4.05∶0.98∶0.84∶0.96∶13.64和1.46∶4.75∶1.04∶2.10∶1.64∶23.92。体外抗氧化的结果表明,SDF-5具有最强的清除DPPH、ABTS+自由基和Fe3+还原力3种抗氧化活性。 

Composition analysis and antioxidant activities of okara soluble dietary fiber prepared by a variety of enzymes

In this study,enzymatic preparation with cellulase and α- amylase and ethanol fractionation precipitation method were used to obtain three different okara soluble dietary fiber( SDF- 1,SDF- 3,SDF- 5),and their composition and antioxidant activity were investgated by gas chromatography,infrared spectroscopy,and in vitro evaluation method.The results showed that the total sugar and galacturonic acid content contained in SDF-1 were the highest,53.44% and 20.43%,respectively,while SDF-5 had the highest reducing sugar content of 10.56%.GC analysis revealed that SDF-1 was composed of Ara,Man,Glu and Gal with a molar ratio of 1.21 ∶ 1.60 ∶ 4.90 ∶ 1.33,both SDF-3 and SDF-5 were composed of Rha,Ara,Xyl,Man,Glu and Gal,with a molar ratio of 2.00 ∶ 4.05 ∶ 0.98 ∶0.84∶ 0.96∶ 13.64 and 1.46 ∶ 4.75 ∶ 1.04 ∶ 2.10 ∶ 1.64 ∶ 23.92,respectively. SDF- 5 exhibited the strongest antioxidant activities in three okara SDFs,evidenced by its ability to scavenge DPPH and ABTS radicals,high reducing power.Based on the results above,it could establish foundation for further development and utilization of soluble dietary fiber from okara.