探索壳聚糖法分离乳清粉中酪蛋白糖巨肽的工艺条件，通过单因素试验考察混合液pH值、壳聚糖添加量、吸附时间、氯化钠浓度和pH值对酪蛋白糖巨肽分离效果的影响。结果表明最佳分离工艺条件为：在混合液pH4.6时，采用质量浓度2g/L的壳聚糖吸附60min，再用2mol/L、pH9的氯化钠溶液进行洗脱。洗脱液经过超滤除盐、浓缩和冷冻干燥后可获得酪蛋白糖巨肽干粉。采用上述工艺进行放大实验，酪蛋白糖巨肽和唾液酸的回收率分别为83.3%和70.64%，每克酪蛋白糖巨肽含有10mg唾液酸。电泳检测结果显示制备的酪蛋白糖巨肽主要是分子质量约22ku和30ku的酪蛋白糖巨肽多聚体。%This study aimed to investigate process conditions for the isolation of casein glycomacropeptide (CGMP) from whey powder by chitosan adsorption. The effects of final pH, final chitosan concentration and adsorption time as well as NaCl concentration and pH for CGMP elution on the efficacy of chitosan for isolating CGMP were explored. The optimum conditions for the isolation of CGMP were determined as follows: chitosan was added to a final concentration of 2 g/L and the pH was adjusted to 4.6 for adsorption of CGMP by chitosan for 60 min; the adsorbed CGMP was then eluted using 2 mol/L NaCl solution alkalified to pH 9; finally the resultant eluate was pooled, desalinate by means of ultrafiltration, concentrated and lyophilized. As a result, CGMP powder was obtained. The results of scale-up experiments showed that the recovery rates of CGMP and sialic acid were 83.3% and 70.64%, respectively and that the CGMP obtained contained 10 mg of sialic acid per gram of sample. This CGMP was composed of a multimer with respective molecular weights of 22 ku and 30 ku as demonstrated by gel electrophoresis analysis.
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