[关键词]
[摘要]
本文研究了高静压结合酶解处理对白果蛋白抗原性的影响,分别采用4种蛋白酶水解白果蛋白,水解前分别采用不同压力的高静压对白果蛋白进行预处理,酶解产物水解率和分子量采用OPA法和SDS-PAGE测定,致敏性采用western-blotting和ELISA法测定。结果表明,木瓜蛋白酶,碱性蛋白酶或胃蛋白酶为水解酶时,高静压能显著提高白果蛋白的水解率和降低其致敏性;而中性蛋白酶为水解酶时,白果蛋白的水解和脱敏效果很差,即使高压处理也未见明显提高。木瓜蛋白酶或碱性蛋白酶在处理压力为300 MPa时,而胃蛋白酶在400 MPa时,其水解和脱敏效果最好,在此条件下白果蛋白能被水解为分子量小于15 ku的多肽,95%以上的白果蛋白致敏性能被消除,酶解产物中致敏蛋白条带全部消失。因此,高静压处理能明显提高蛋白酶对白果蛋白的水解效率和脱敏效果,但是取决于选择的蛋白酶种类和处理压力的大小。
[Key word]
[Abstract]
The purpose of this paper was to study the combined effect of high hydrostatic pressure (HHP) and enzymatic hydrolysis treatments on the allergenicity of ginkgo seed proteins (GSP). Four food-grade proteases (papain, alcalase, pepsin, and neutrase) were used to hydrolyze GSP after pre-treatment with HHP (200, 300, or 400 MPa). The extent of hydrolysis and molecular weights of the hydrolysates were measured by the o-phthaldialdehyde (OPA) method and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and the allergenicity was assessed by western blotting and enzyme-linked immunosorbent assay (ELISA). The results showed that HHP could significantly improve the extent of proteolysis and reduce the antigenicity of GSP when the hydrolase was papain, alcalase, or pepsin, whereas neutrase showed a low degree of proteolysis and poor anti-allergenicity on GSP, and no significant improvement was observed upon high-pressure treatment. The highest degree of proteolysis and the optimal anti-allergenicity were obtained with papain or alcalase hydrolysis combined with HHPtreatment at 300 MPa or with pepsin hydrolysis combined with HHP treatment at 400 MPa. Under the above conditions, GSP could be hydrolyzed into polypeptides with molecular weights lower than 15 ku, the antigenicity was reduced over 95%, and all immunoreactive bands disappeared in the hydrolysates obtained. These results suggest that HHP can improve the degree of hydrolysis of GSP and reduce the residual antigenicity of hydrolysates, but the effects are dependent on the protease used and the magnitude of processing pressure.
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[基金项目]
江苏省自然科学基金项目(BK20141073);江苏省林业三新工程项目(LYSX[2015]25);“十二五”国家科技支撑计划项目(2012BAD21B04)