Glutamine peptides were obtained from defatted soybean meal by enzymatic hydrolysis using a combination of Protamex~? and trypsinase. The results showed that the extent of hydrolysis and the concentration of Gln pepti...Glutamine peptides were obtained from defatted soybean meal by enzymatic hydrolysis using a combination of Protamex~? and trypsinase. The results showed that the extent of hydrolysis and the concentration of Gln peptides in the hydrolysate were 22.02%and 6.05 mmol/L, respectively. The hydrolysates were fractionated by size-exclusion chromatography on a Sephadex G-15 into five major fractions(GelF1–GelF5). The peptide(GelF1) fraction with the highest glutamine peptide content(51.8%) was further evaluated to determine its molecular weight distribution. Most(92.37%) peptides were less than 1 000 Da. Glutamic acid and glutamine were the most abundant amino acids, accounting for up to 12.98% of the total amino acid content. In addition, the total amino acid content in GelF1 was higher than that in GelF2 and GelF3.展开更多
本文通过单螺杆挤压机改性白酒糟(Distiller's grains,DGs),研究了挤压物料水分(21%、24%、27%、30%、33%)对白酒糟醇溶蛋白(Prolamins from distiller's grains,PDGs)理化(溶解度、表面疏水性、巯基和二硫键含量)、功能(持水...本文通过单螺杆挤压机改性白酒糟(Distiller's grains,DGs),研究了挤压物料水分(21%、24%、27%、30%、33%)对白酒糟醇溶蛋白(Prolamins from distiller's grains,PDGs)理化(溶解度、表面疏水性、巯基和二硫键含量)、功能(持水、持油能力)和二、三级结构等性质的影响。结果表明,不同挤压物料水分对PDGs改性效果具有显著影响,随物料水分增加,挤压对PDGs天然结构的破坏程度逐渐增大,分子构象的改变促进内部亲水基团的暴露和二硫键的生成,物料水分为27%时,溶解度提高了1.56倍,达到34.75%,表面疏水性降低了56.11%,增强了持水能力,热变性温度由96.79℃增大到102.53℃,热稳定性更强,PDGs经变性重排后,蛋白聚集体有序程度增加。而物料水分过高时(高于27%),挤压造成PDGs过度变性,稳定聚集态的破坏反而会弱化其亲水、热特性、有序程度等,说明挤压物料水分对PDGs性质的改变具有十分重要的调控作用。展开更多
基金Supported by National Key R&D Program of China(2016YFD0400203)
文摘Glutamine peptides were obtained from defatted soybean meal by enzymatic hydrolysis using a combination of Protamex~? and trypsinase. The results showed that the extent of hydrolysis and the concentration of Gln peptides in the hydrolysate were 22.02%and 6.05 mmol/L, respectively. The hydrolysates were fractionated by size-exclusion chromatography on a Sephadex G-15 into five major fractions(GelF1–GelF5). The peptide(GelF1) fraction with the highest glutamine peptide content(51.8%) was further evaluated to determine its molecular weight distribution. Most(92.37%) peptides were less than 1 000 Da. Glutamic acid and glutamine were the most abundant amino acids, accounting for up to 12.98% of the total amino acid content. In addition, the total amino acid content in GelF1 was higher than that in GelF2 and GelF3.
文摘本文通过单螺杆挤压机改性白酒糟(Distiller's grains,DGs),研究了挤压物料水分(21%、24%、27%、30%、33%)对白酒糟醇溶蛋白(Prolamins from distiller's grains,PDGs)理化(溶解度、表面疏水性、巯基和二硫键含量)、功能(持水、持油能力)和二、三级结构等性质的影响。结果表明,不同挤压物料水分对PDGs改性效果具有显著影响,随物料水分增加,挤压对PDGs天然结构的破坏程度逐渐增大,分子构象的改变促进内部亲水基团的暴露和二硫键的生成,物料水分为27%时,溶解度提高了1.56倍,达到34.75%,表面疏水性降低了56.11%,增强了持水能力,热变性温度由96.79℃增大到102.53℃,热稳定性更强,PDGs经变性重排后,蛋白聚集体有序程度增加。而物料水分过高时(高于27%),挤压造成PDGs过度变性,稳定聚集态的破坏反而会弱化其亲水、热特性、有序程度等,说明挤压物料水分对PDGs性质的改变具有十分重要的调控作用。
