Ultra-High Performance Liquid Chromatography Combined with Pre-column Derivatization for Quantification of Free Amino Acids in Poria / 中国药学杂志

ABSTRACT

OBJECTIVE: To establish the quantification method for free amino acids including threonine, alanine, lysine and tyrosine in the inner part of Poria cocos. METHODS: AQC (6-quinolyl-N-hydroxy-succinimidyl-carboxylate) was used as deriving reagent, and pre-column derivatization combined with ultra-high performance chromatography was applied to quantify threonine, alanine, lysine and tyrosine in 24 batches of the inner part of Poria cocos from Yunnan, Hubei and Anhui provinces. The experimental data were analyzed by partial least squares discriminant analysis (PLS-DA) using Simca-p+11 software. RESULTS: Alanine existed in every batch of sample, and its content ranged from 16.97-69.92 μg·g-1 in samples collected from different origins. Threonine, lysine and tyrosine were not found in some samples. The PLS-DA result showed that the samples from Yunnan and Anhui provinces clustered well. While the amino acid contents in the samples from Hubei province varied greatly. CONCLUSION: AQC combined with pre-column derivatization is a convenient, rapid and sensitive method to quantify the free amino acids in Poria.