反相高效液相色谱法评价烟台苹果中游离氨基酸

利用反相高效液相色谱法对烟台境内多地红富士苹果中游离氨基酸含量进行检测和分析.色谱条件为:Capcell PAK C18色谱柱(4.6 mm×150 mm,3μm),以10 mmol/L磷酸氢二钠和10 mmol/L硼酸钠的缓冲溶液(pH 8.2)为流动相A,乙腈-甲醇-水(45∶45∶10,V/V/V)为流动相B,梯度洗脱,流速1.5 mL/min,外标法定量,检测波长为338 nm和262 nm.在10¹ 000 pmol/μL浓度范围内,17种氨基酸线性关系良好(R2>0.999),峰面积的精密度(RSD):1.47%1 000 pmol/μL浓度范围内,17种氨基酸线性关系良好(R2>0.999),峰面积的精密度(RSD):1.47%³.84%,回收率91%3.84%,回收率91%¹11%.8种烟台红富士苹果中游离氨基酸总量为47.0111%.8种烟台红富士苹果中游离氨基酸总量为47.0¹40.9μg/g,必需氨基酸的含量比例为6.6%140.9μg/g,必需氨基酸的含量比例为6.6%²9.5%,不同产地苹果中氨基酸含量在极差0.05水平上有显著性差异,对测定值分别进行聚类分析和主成分分析,8种不同产地的苹果样品可分为3类.

Evaluation of Free Amino Acids in Flesh of Yantai Apple by RP-HPLC

A reversed-phase high performance liquid chromatography （RP-HPLC） method is used to measure and evaluate the contents of 17 kinds of free amino acids in Red Fuji Apples from different place of origin in Yantai.The separation is performed on Capcell PAK C18 column （4.6 mm × 150 mm,3 μm）.10 mmol/LNa2HPO4 and 10 mmol/L Na2B4O7 buffer solution （pH 8.2） are used as mobile phase A and a mixture of acetonitrile,methanol and water （45∶ 45∶ 10） as B.Gradient elution is proceeded at a flow rate of 1.5 mL/min and the contents of amino acids are quantitied by external standard method.Linear calibration of 17 amino acid standard is good in the range of 10 pmol/μL to 1000 pmol/μL at 338 nm and 262 nm （R2 〉0.999）.The method precision （RSD） of peak area is in the range of 1.47% to 3.84%,and recovery ratio is 91% to 111%.The contents of amino acids in 8 kinds of Yantai apples vary from 47.0 μg/g to 140.9 μg/g and the ratio of essential amino-acid ranges from 6.6% to 29.5%.There is a significant difference of the contents of amino acid at 0.05 level by Duncans test.On basis of the contents of amino acids,both cluster analysis and principal component analysis are conducted on Yantai Apples,which can be clustered into 3 groups.