反相高效液相色谱法同时测定咖啡豆中的6种酚酸类化合物

建立了同时测定咖啡豆中6种酚酸类化合物(咖啡酸、3-咖啡酰奎尼酸、4-咖啡酰奎尼酸、5-咖啡酰奎尼酸、3,5-二咖啡酰奎尼酸、4,5-二咖啡酰奎尼酸)的反相高效液相色谱测定方法。采用Kromasil C18柱(200 mm×4.6 mm, 5 μm),以乙腈和0.1%甲酸水溶液为流动相进行梯度洗脱,二极管阵列检测器检测,45 min内可对6种目标物进行同时检测,且各化合物都能达到基线分离。经测定,样品中6种酚酸类化合物的加标回收率为90.76%～104.73%,相对标准偏差为0.7%～3.9%。该法简便、快速、灵敏度高,适用于咖啡豆中6种酚酸类化合物的同时分析以及咖啡豆原料与制品的质量控制和综合评价。

Simultaneous determination of 6 phenolic acids in coffee beans by reversed-phase high performance liquid chromatography

A method of reversed-phase high performance liquid chromatography coupled with diode array detection (HPLC-DAD) was established for the simultaneous determination of 6 phenolic acids in green coffee beans. These phenolic acids are caffeic acid, 3-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, 5-O-caffeoylquinic acid, 3,5-O-dicaffeoylquinic acid and 4,5-O-dicaffeoylquinic acid. The separation was achieved using a Kromasil C18 column (200 mm x 4.6 mm, 5 microm) under the gradient elution with the mobile phases of acetonitrile and 0.1% (v/v) formic acid/water. The 6 phenolic acids were well separated within 45 min. The recoveries were from 90.76% to 104.73% with the relative standard deviations between 0.7% and 3.9%. The method is simple, rapid and highly sensitive, suitable for the simultaneous determination of 6 phenolic acids and quality control of coffee beans.