水酶法水解液中大豆多肽的吸附纯化及其氨基酸组成分析

Purification and amino acid composition ofpeptides from soybean byproduct protein hydrolysate fromaqueous enzymatic extraction of soybean Oil

考察大孔吸附树脂对水酶法水解液中大豆多肽的吸附性能和纯化效果,通过静态吸附和解吸实验对8种树脂进行了初步筛选,并进一步研究了上样体积、上样流速、解吸剂体积分数等条件对大孔吸附树脂纯化能力的影响。结果表明:DA201-C大孔吸附树脂对水酶法大豆多肽的吸附性能优于其他7种树脂,其最佳动态吸附工艺为:上样体积140 m L、上样流速1.5 m L/min、水洗体积350 m L,体积分数25%、50%、75%、100%乙醇溶液分级洗脱,每次80 m L,流速2 m L/min。经纯化后各大豆多肽组分纯度均在80%以上,总回收率为95.65%,树脂吸附量为13.32 mg/g,糖类及盐类杂质分别降低51%及90%以上;乙醇分级洗脱可分离4个大豆多肽组分,其中75%体积分数组分SP-DA75氧自由基清除能力最强,肽段的抗氧化性与其疏水性氨基酸含量及酸性氨基酸含量具有一定相关性。

In this paper,the adsorption performances and purification efficiencies of 8 macroporous adsorption resins(MARs)for peptides from soybean byproduct protein hydrolysate from aqueous enzymatic extraction of soybean oil were comparatively evaluated by static adsorption and desorption experiments in order to find the best one among these MARs.Further,the effects of feeding volume,feeding rate and desorbent concentration on the purification efficiency of MARs were investigated.Results showed that DA201-C resin had the highest adsorption capability for soybean peptides among 8 resins tested.The optimum dynamic adsorption conditions of DA201-C resin were determined as follows:sample loading volume,140 mL;feeding flow rate,1.5 mL/min;350 mL of water as washing solvent;and fractional elution with 25%,50%,75%and 100%using 80 mL of each concentration gradient at 2 mL/min flow rate.Under these conditions,the purity of the purified soybean peptides reached above 80%with a total recovery of 95.65%and a removal rate of more than 90%and 51%for salt and sugar impurities,respectively,and the adsorption capacity of DA201-C resin was 13.32 mg/g.Four soybean peptide fractions were separated by fractional elution with ethanol.A fraction eluted with 75%ethanol,SP-DA75,showed the highest oxygen radical adsorption capacity(ORAC)among the four fractions.Moreover,there was a correlation between antioxidant activities of peptide fragments and their contents of hydrophobic amino acids and acidic amino acids.In conclusion,DA201-C resin exhibited excellent adsorption performance and could be applied as an effective method to purify soybean peptides.