反胶团萃取分离葡萄酒下脚料中葡萄皮蛋白质

采用阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)反胶团萃取葡萄皮中的蛋白质。分别考察水相pH值、表面活性剂浓度、离子强度、蛋白质浓度、有机溶剂与助剂种类和比例、萃取温度对前萃取率的影响,并采用二次正交旋转组合的试验方法,考察前萃取过程中离子强度、表面活性剂浓度、水相pH值对前萃取率的影响。结果表明:32.68 mmol/L CTAB/三氯甲烷-正丁醇(体积比4∶1)的反胶团体系用于前萃取水相pH为6.4,包含0.4 mol/L NaCl的葡萄皮中蛋白质的浸提液,前萃取率可达56.54%。理想的前萃取条件是:pH 6.4、NaCl浓度0.4 mol/L、CTAB浓度32.68 mmol/L、蛋白质浓度1 mg/mL、萃取温度30℃。在该条件下,采用pH 3.8、后萃取温度20℃、0.8 mol/L NaCl水相进行后萃取,后萃取率可达71.29%。

Separation of Grape Skins Protein from Wine Sediment by Reversed Micelles Extraction

Extraction of protein from grape skins was investigated with reversed micelles extraction by using cationic surfactant CTAB.Effect of some parameters,such as pH value in aqueous phase,the content of surfactant,ionic strength,concentration of grape skins protein,the species and volume of organic solvent and co-solvent in reversed micellar solution as well as temperature,on the extraction ratio of grape skins protein was examined.Quadratic orthogonal rotation combination experiments were conducted to investigate the effects of concentrations of surfactant,ionic strength and pH value on the extraction rate.The forward-extraction yield of protein was found as high as 56.54% by 32.68mmol/L CTAB /Chloroform/ n-butane(4∶1,v/v)from the supernatant with pH 6.4,0.4mol/L NaCl.The best extraction condition was pH value 6.4,concentrations of surfactant 32.68mmol/L,protein concentration 1mg/mL,NaCl concentration 0.4mol/L,temperature 30℃.Under this condition: the backward extraction yield was 71.29% by 0.8 mol/L NaCl solution,temperature 20℃with pH3.8 as backwards extraction condition.