柱前衍生-超高效液相色谱测定不同品种桑枝中的17种氨基酸的含量

Determination of 17 amino acids in different varieties of mulberry branches by ultra-high performance liquid chromatography with precolumn derivatization

为研究桑枝氨基酸含量情况,采用酸水解、异硫氰酸苯酯柱前衍生、超高效液相色谱仪法对采自重庆不同区县的9个采样点、3个品种共18批次桑枝中的17种氨基酸含量进行测定。结果表明,17种氨基酸在各自质量浓度范围内,峰面积和浓度呈现良好的线性关系,相关系数r为0.9979~0.9999。18批次桑枝样品中均检出17种氨基酸,桑枝中氨基酸总量为41.09~111.70 mg/g,平均含量为64.48 mg/g;必需氨基酸的总含量为16.88~35.45 mg/g,平均含量为23.53 mg/g;药用氨基酸总量为22.98~59.99 mg/g,平均含量为35.58 mg/g。不同品种桑枝在氨基酸种类上基本无差异,但含量差异较大,其中含量最高的脯氨酸和谷氨酸平均含量为10.49 mg/g和6.37 mg/g,分别占氨基酸总量的16.27%和9.88%。结果表明桑枝中氨基酸种类丰富,含量较高。该研究可为深入研究桑枝的药用价值提供基础资料。

In this study,acid hydrolysis,phenyl isothiocyanate pre-column derivatization and ultra-high performance liquid chroma-tography were used to explore the content of amino acids in mulberry branches.UPLC method was used to determine the content of 17 ami-no acids in 18 batches,3 varieties of mulberry branches collected from 9 sampling points in Chongqing.The results showed that there was a good linear relationship between the peak area and concentration of 17 amino acids in the range of respective mass concentrations with a correlation coefficient r 0.9979-0.9999.The total amount of amino acids in mulberry branches was 41.09-111.70 mg/g,on the av-erage of 64.48 mg/g;the total content of essential amino acids ranges from 16.88 mg/g to 35.45 mg/g,on the average of 23.53 mg/g.Moreover,the total content of medicinal amino acids ranged from 22.98 mg/g to 59.99 mg/g,on the average of 35.58 mg/g.There was no difference in amino acids types among different varieties of mulberry branches,but the content of amino acids varied greatly.The aver-age content of proline and glutamate with the highest two were 10.49 mg/g and 6.37 mg/g,which accounting for 16.27%and 9.88%of the total amino acids,respectively.The results showed that the type of amino acids in mulberry branches were abundant and with relative-ly high concentration.This study could provide basic data for further explore the medicinal value of mulberry branches.