OPA柱前衍生化HPLC同时测定川红工夫红茶20种氨基酸含量  

Simultaneous determination of 20 amino acids in Sichuan black tea by the method of online pre-column OPA derivatization HPLC

作　　者：罗学平[1,2] 蒋宾 李丽霞 钟晓雪[1,2] 杨丽冉 焦文文 彭康丽 陈岗 LUO Xueping;JIANG Bin;LI Lixia;ZHONG Xiaoxue;YANG Liran;JIAO Wenwen;PENG Kangli;CHEN Gang(College of Modern Agriculture,Yibin Vocational and Technical College,Yibin,Sichuan 644003,China;Yibin Chuanhong Gongfu Black Tea Engineering Technology Research Center,Yibin,Sichuan 644000,China)

机构地区：[1]宜宾职业技术学院现代农业学院,四川宜宾644003 [2]宜宾川红工夫红茶工程技术研究中心,四川宜宾644000

出　　处：《贵州师范大学学报（自然科学版）》2024年第4期53-62,共10页Journal of Guizhou Normal University：Natural Sciences

基　　金：四川省科技厅重点研发项目(2021YFN0091);宜宾职院科技创新团队项目(ybzy20cxtd06);宜宾职院科研项目(zrky21yb-06、zrky21yb-07)。

摘　　要：建立在线柱前衍生液相色谱法同时测定不同品种川红工夫红茶中的20种氨基酸含量,并评价其与滋味品质相关性。以邻苯二甲醛(OPA)为衍生试剂,利用液相色谱仪的自动进样器进行柱前衍生,采用Hypersil BDS C 18柱(150 mm×4.6 mm,3μm),以0.016 mol/L的磷酸盐缓冲液(pH=8.2)与甲醇-乙腈-水(4.5∶4.5∶1,V∶V∶V)组成流动相进行梯度洗脱,流速为1.0 mL/min,柱温50℃,荧光检测器激发波长340 nm、发射波长450 nm;通过相关分析,比较不同滋味属性氨基酸含量与红茶滋味的相关性。结果表明:20种氨基酸在0.195~2.584μg/mL的范围内与各自峰面积呈良好的线性关系,其相关系数为0.9954~0.9999,检测限为0.006~0.036μg/mL,定量限为0.020~0.184μg/mL,加标回收率为90.40%~99.13%;除四川群体种红茶和梅占红茶中未检出组氨酸外,其余氨基酸均在5个品种红茶中检出,氨基酸总量27.33~65.29 mg/g之间,其中含量最高的是黄金芽红茶,氨基酸组分中,含量最高的是茶氨酸,然后是天冬氨酸和谷氨酸;红茶中的鲜味氨基酸、甜味氨基酸、苦味氨基酸、氨基酸总量与红茶的鲜味、甜味和综合滋味评分呈显著或极显著正相关,对红茶滋味的鲜爽度和浓强度起着重要作用。采用OPA柱前衍生反相液相色谱荧光法检测氨基酸组分精密度和回收率高,具有成本低、快速、准确的特点,可用于红茶中20种氨基酸组分的快速测定。To establish a method of online pre-column derivatization HPLC for simultaneous determination of 20 amino acids in different varieties of Sichuan black tea,and to evaluate their correlation with taste quality,Ortho phthalaldehyde(OPA)was used as a derivative reagent,and derivatized in the automatic sampler of liquid chromatograph.The derivatives of amino acids were separated by gradient elution with phosphate buffer(0.016 mol/L,pH=8.2)and methanol-acetonitrile-water(4.5∶4.5∶1,V∶V∶V)under the conditions of 1 mL/min and column temperature 50℃in Hypersil BDS C 18 chromatographic column(150 mm×4.6 mm,3μm),and were detected in a fluorescence detector with excitation wavelength 340 nm and emission wavelength 450 nm,then the correlation between amino acid contents of different flavor attributes and the taste of black tea was compared through correlation analysis.Results showed that:The 20 amino acids showed a good linear relationship with their respective peak areas from 0.195 to 2.584μg/mL with correlation coefficients ranging from 0.9954 to 0.9999,their detection limit was between 0.006~0.036μg/mL,the quantification limit was 0.020~0.184μg/mL,and the spiked recovery rate ranged from 90.40%to 99.13%.With the exception of histidine that was not detected in black teas prepared with Sichuan populations tea plant and Meizhan tea plant,other amino acids were dectected in 5 black teas with a content of 27.33~65.29 mg/g,and the highest content of variety was Huangjinya black tea.Among the amino acid components,the highest content was theanine,followed by aspartic acid and glutamic acid.Through relevant analysis,it showed that there was a significant or extremely significant positive correlation between the content of fresh amino acids,bitter amino acids,sweet amino acids,total amino acids to the scored of freshness,sweetness and overall taste,and they played an important role in freshness and intensity of the taste of black tea.The pre-column OPA derivatization HPLC has high precision and recovery rate in detec

关 键 词：邻苯二甲醛 柱前衍生 川红工夫红茶 氨基酸 

分 类 号：O657.7[理学—分析化学] TS272[理学—化学]