采用不同截留分子质量的超滤膜对紫贻贝酶解物进行超滤分离,确定了一级超滤的条件,并比较超滤前后酶解物的ACE抑制活性、分子量分布及组成变化。结果表明:采用操作压力138kPa,操作温度25℃,料液浓度15g/L的超滤条件,截留分子质量为10ku的超滤膜能将紫贻贝酶解物的ACE抑制率提高到89.42%,IC50也降低到40.03μg/mL;同时,一级超滤能够有效截留多糖化合物,而富集多肽,但对于表观分子量分布没有显著影响。

The effects of ultrafiltration on Angiotensin-I converted enzyme(ACE)inhibitory activity,molecular weight distribution and composition of Mytilus edulis protein hydrolysates were investigated.The results showed that the optimum conditions of the first-degree ultrafiltration are:pressure 138 kPa,temperature 20℃ and concentration 15g/L.The permeate fractions of 10 KD membrane showed higher ACE inhibitory activity than original hydrolysates.Meanwhile,ultrafiltration can effectively cut off the polysaccharides and concentrate the ACE inhibitory peptides.However,the effect of ultrafiltration on molecular weight distribution was not as obvious.