膜分离耦合离子交换层析制备高纯度α-乳白蛋白

Membrane Separation Followed by Ion Exchange Chromatography for Preparation of High-Purityα-Lactalbumin

以生牛乳为原料,经膜分离及喷雾干燥制得鲜乳乳清蛋白粉,结合离子交换层析制备高纯度α-乳白蛋白。结果表明:在浓缩3倍、微滤1次、洗滤2次的膜分离条件下,50 nm陶瓷膜渗透液中α-乳白蛋白占真蛋白的21.04%,高于100 nm陶瓷膜渗透液(15.84%);对50 nm陶瓷膜渗透液进行喷雾干燥,并进行离子交换层析,层析时,在10倍柱体积内,Na Cl溶液浓度由0 mol/L增至0.5 mol/L,α-乳白蛋白与β-乳球蛋白能较好地分离,得到的α-乳白蛋白和β-乳球蛋白纯度分别为98.18%和97.82%。本研究结果可为工业化制备高纯度α-乳白蛋白乳基料提供技术支持。

In this study,ion exchange chromatography was employed to prepare high-purityα-lactalbumin from whey protein powder obtained from raw cow’s milk by sequential membrane separation and spray drying.The results showed thatα-lactalbumin constituted 21.04%of the true protein in the permeate obtained using a 50-nm pore-sized ceramic membrane with three-fold concentration,one cycle of microfiltration and two cycles of washing,which was higher than that obtained using a 100-nm pore-sized ceramic membrane(15.84%).The permeate was spray dried and separated by ion exchange chromatography.Good chromatographic separation ofα-lactalbumin andβ-lactoglobulin was achieved with increasing NaCl concentration from 0 to 0.5 mol/L at up to 10 column volumes,and 98.18%pureα-lactalbumin and 97.82%pureβ-lactoglobulin were obtained.The results of this study provide support for the industrial preparation of high-purityα-lactalbumin.