羊乳表皮生长因子(EGF)在人工模拟胃肠液中的稳定性

Study on the stability of goat milk EGF in simulated gastrointestinal fluid

文中在研究羊乳EGF和EGF标品在人工胃液、人工肠液和人工胃肠液中消化稳定性的基础上,研究添加乳成分和食源性蛋白酶抑制剂的EGF标品在人工胃液和人工肠液中的稳定性。结果表明:羊乳中EGF浓度在人工胃液、人工肠液或人工胃肠液中消化1 h内迅速下降,消化1 h后基本稳定,但与纯EGF消化程度相比,羊乳中EGF消化速度明显降低;通过研究添加乳成分的EGF样品在人工胃肠液中的消化稳定性,发现在人工胃液中,乳清和乳清液对EGF的消化有保护作用,而酪蛋白和乳清蛋白对EGF的消化无保护作用,在人工肠液中,乳清、乳清液、酪蛋白和乳清蛋白均能对EGF的消化产生保护作用;通过研究添加食源性蛋白酶抑制剂和乳清液的EGF样品在人工胃肠液中的消化稳定性,发现在人工胃液中,乳清液(GMSF)对EGF的消化有保护作用,而大豆蛋白酶抑制剂(SBTI)、青豆蛋白酶抑制剂(LBTI)、蛋清蛋白酶抑制剂(EWPI)对EGF的消化无保护作用;在人工肠液中,大豆蛋白酶抑制剂(SBTI)、青豆蛋白酶抑制剂(LBTI)、蛋清蛋白酶抑制剂(EWPI)和乳清液(GMSF)对EGF的消化均产生保护作用。

The digestion stability of goat milk EGF and EGF standard in artificial gastric,intestinal juice and artificial gastrointestinal juice were studied and based on its result,the stability of EGF standard which has goat milk composition and food protease in artificial gastrointestinal fluid was investigated. The results showed that EGF concentration in goat milk digested rapidly in artificial gastric,intestinal juice and artificial gastrointestinal within 1 hour. It became stable after 1 h,but compared with the pure EGF,EGF digestion rate was significantly lower in goat milk.the digestive stability of EGF with milk composition in artificial gastrointestinal fluid showed that whey and whey liquid protected the digestion of EGF in the artificial gastric juice,while casein and whey protein did not have the protective effect. Whey,whey liquid,casein and whey protein all had protective effect on the digestion of EGF in artificial intestinal juice. The digestive stability of EGF with food protease inhibitor and goat milk-soluble fraction in artificial gastrointestinal fluid showed that goat milk-soluble fraction had protective effect on the digestion of EGF in artificial gastric juice while soya bean trypsin inhibitor,lima bean trypsin inhibitor and egg white trypsin inhibitor had no protective effect. Meanwhile,soya bean trypsin inhibitor,lima bean trypsin inhibitor,egg white trypsin inhibitor and goat milksoluble fraction all had protective effect on EGF in artificial intestinal juice.