酪蛋白酶解物中抗菌肽的分离及其分子量的测定

使用离子交换层析分离纯化酪蛋白酶解物中的抗菌肽并测定其分子量。选用Q-Sepharose Fast Flow为分离介质,对分离条件进行了研究,并对各洗脱组分进行抑菌活性测定,确定了适宜分离条件下酪蛋白抗菌肽的洗脱体积,同时测定了酪蛋白抗菌肽的分子量。结果表明,离子交换层析对酪蛋白酶解物中的抗菌肽的最佳梯度洗脱条件为:流动相A:pH10.5的0.05mol/L乙醇胺盐酸缓冲液;流动相Β:含1mol/L氯化钠的A相溶液,pH10.5;洗脱程序:7%B,1.55CV;13%B,1.40CV;25%B,1.25CV;100%B,1.55CV,洗脱流速:0.5mL/min,检测波长:280nm,酪蛋白抗菌肽的洗脱体积为76.57mL和89.48mL。酪蛋白抗菌肽的平均分子量为3137u。

Separation and determination of molecular weight of the antibacterial peptides from the casein hydrolysate

Used the ion exchange chromatography to separate antibacterial peptides of the casein hydrolysate whose molecular weights were also determined.By selecting Q-Sepharose Fast Flow as the chromatography medium,the separation conditions were studied and the elution volume of antibacterial peptides of the casein under the optimal separation conditions through the antibacterial performance were determined,and the molecular weight of the antibacterial peptides.The result showed that the optimal step elution conditions of using the ion exchange chromatography to separate antibacterial peptides of the casein hydrolysates were as follows:mobile phase A:0.05mol/L MEA-HCl,pH 10.5;mobile phase B:mobile phase A contain 1mol/L NaCl,pH 10.5,elution program:7%B(1.55CV),13%B(1.40CV),25%B(1.25CV),100%B(1.55CV).Elution flow rate was 0.5mL/min,detection wavelength:280nm.By the further separation,the elution volumes of antibacterial peptides of the casein were 76.57mL and 89.48mL.The peptides’ average molecular weight was measured to be 3137u.