Abstract: In this study, ion exchange chromatography was employed to prepare high-purity α-lactalbumin from whey protein powder obtained from raw cow’s milk by sequential membrane separation and spray drying. The results showed that α-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 of α-lactalbumin and β-lactoglobulin was achieved with increasing NaCl concentration from 0 to 0.5 mol/L at up to 10 column volumes, and 98.18% pure α-lactalbumin and 97.82% pure β-lactoglobulin were obtained. The results of this study provide support for the industrial preparation of high-purity α-lactalbumin.

Key words: α-lactalbumin; β-lactoglobulin; separation and purification; membrane separation; ion exchange chromatography

摘要： 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，NaCl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。

关键词: α-乳白蛋白；β-乳球蛋白；分离纯化；膜分离；离子交换层析