脱酚棉籽蛋白限制性酶解因素的分析

Parameter analysis of limited enzymolysis to de-gossypol cottonseed protein

【目的】对脱酚棉籽蛋白限制性酶解因素进行分析，为提高棉籽蛋白的溶解性提供参考。【方法】采用胰蛋白酶对脱酚棉籽蛋白（CPF）进行限制性酶解，以蛋白质的溶解度和水解度为指标，研究浸泡时间、搅拌方式以及酶解因素（酶用量、体系pH、底物（CPF）质量浓度、酶解温度、时间）对棉籽蛋白水解的影响。【结果】将棉籽蛋白于酶解前在3倍量（mL／g）去离子水中浸泡3h有利于酶解。在酶用量为75kU／g、pH为8、底物质量浓度为80g／L、50℃条件下磁力搅拌（120r／min）酶解3h，可得到水解度为10．67％、溶解度为54．47％的酶解棉籽蛋白。溶解度分析结果表明，限制性酶解棉籽蛋白在pH1～11时具有较好的溶解度，且保持了棉籽蛋白酸溶性的特点。【结论】用胰蛋白酶限制性水解脱酚棉籽蛋白，既可以显著提高棉籽蛋白的溶解度，又保持了其酸溶性的特点。

[Objective] To provide some references for improving the solubility of cottonseed protein, the limited enzymolysis parameters of de-gossypol cottonseed protein were analyzed. [Method] The cottonseed protein was partially hydrolyzed by trypsinase. Taking solubility and degree of hydrolysis （DH） as e- valuation index,the steeping time before enzymolysis,mixing ways and the enzymolysis parameters （such as trypsinase concentration, substrate concentration, pH value and temperature） were investigated in this paper. [Result] Steeping the cottonseed protein flour in three times de-ionized water （mL/g） before en- zyme hydrolysis is helpful to enzymolysis. In this test, a proper DH （10. 67%） and a higher solubility （54.47%） of cottonseed protein can be obtained on the condition of trypsinase concentration 75 kU/g,pH value 8,CPF mass concentration 80 g/L,the temperature 50℃ and hydrolysed 3 h with magnetic force stiring （120 r/min）. The results of solubilty analyzed in different pH solutions show that the enzymolytic cottonseed protein has higher solubility in pH value from 1 to 11 ,and it still maintains the acid-soluble character of cottonseed protein before enzymolysis. [Conclusion] The solubility of de-gossypol cottonseed protein can be significantly improved by limited hydrolyzed with trypsinase in proper condition,and the acid-soluble character of cottonseed protein is remained.