酶法制备乳铁蛋白抗菌肽的工艺

Preparation of Antimicrobial Peptides from Lactoferrin by Enzymatic Hydrolysis

乳铁蛋白具有抗菌活性,胃蛋白酶酶解乳铁蛋白时得到的乳铁蛋白多肽的抗菌活性远高于其自身。通过响应面回归分析,得到了胃蛋白酶酶解乳铁蛋白的优化条件为:底物浓度30 mg/mL、水解时间2 h、温度45℃、加酶量1%(w/w)、pH 2.5。在优化酶解条件下,水解度约为11%,抑菌率为98.8%。高效液相排阻色谱分析表明,多肽的分子质量主要分布在200～6 000 u。

Lactoferrin （LF） is a kind of muhifunctional protein with antimicrobial property. When it was hydrolyzed by pepsin, stronger antimicrobial activity peptides generated. The objective of the study is to optimize the conditions of enzymatic hydrolysis with pepsin. By response surface regression analysis, the optimum enzyme hydrolysis conditions were achieved as substrate （S]）30 mg/mL, time 2 h, temperature （T） 45℃, enzyme： substrate ratio （[E]/[S]）1% （w/w）, and pH 2.5. The resulted degree of hydrolylsis （DH） was about 11%, and inhibitory activity （Y） was about 98.8%. By high performance size exclusion chromatography （HPSEC）, it was suggested that molecular masses of the digestion of LF by pepsin were between 200-6 000 u.