期刊论文

Determination of protein in celery by salicylic acid-indophenol blue spectrophotometry

中文

中国卫生检验杂志

1004-8685

2009

19

11

2553-2554,2677

本校为第一机构

目的：建立水杨酸-靛酚蓝光度法间接测定芹菜中蛋白质含量的新方法。方法：样品经过浓硫酸消化后生成的NH4＋,在亚硝基铁***催化作用下,与水杨酸等试剂在30℃水浴中反应1 h,生成蓝色的靛酚蓝物质在636 nm处有最大吸收,以吸光度A对NH4＋浓度进行线性回归,间接测定芹菜样品中蛋白质的含量。结果：显色产物最大吸收波长为636 nm,NH4＋浓度在2.82×10^-6-0.21×10^-3mol/L范围内,A与其浓度呈良好线性关系,回归方程为：A=4.32C＋0.0024,相关系数r=0.9999。方法检出限为0.739μg（以蛋白质计）,相对标准偏差为1.34%。用此方法测得芹菜杆中蛋白质含量为6.66 mg/g（以湿重计）,芹菜叶中蛋白质含量为7...

Objective：A new method of indirect determination of protein in celery was developed by salicylic acid-indophenol blue spcetrophotometry.Methods：The protein in celery sample was digested into NH＋4 by the use of concentrated sulfuric acid.NH＋4 reacted with the reagent of salicylic acid when sodium nitroferricyanide dihydrate was present as a catalyst,with water bath of 30℃ for 1h to form blue product.The absorption spectra of the blue product was scanned and it showed that it had the maximal absorption at 636 nm.Results：The linear regress e...