凯氏定氮法测定啤酒酵母碱溶性多糖中蛋白质的质量分数

Determination of protein content in a alkaline-soluble polysaccharide of Beer Yeast by Kjeldahl method

从啤酒酵母中提取出碱溶性粗多糖ASP,经乙醇分级、savag法脱蛋白以及分子筛层析进一步纯化得ASP2和ASP3,采用半微量凯氏定氮法,通过消化、蒸馏、滴定后计算其蛋白质质量分数,ASP,ASP2,ASP3分别为15.41%,3.17%和2.89%.

A alkaline-soluble crude polysaccharide ASP isolated from the caput-mdusa of S. cerevisiae has been fractionated. The matter was been deproteinizationed by the evage, alcohol fractional precipitation and purified by column chromatography. So ASP2 and ASP3was abtained by purification further. Which were digested and distilled and titrated with hydrochloric acid standard solution to give the protein content of ASP, ASP2 and ASP3＇were determined 15.41%, 3.17% and 2. 89 % respectively.