ABSTRACT
Objective: A method for simultaneous determination of nine active organic acids [shikimic acid, catechinic, (-)- epicatechin, gallic acid, protocatechuic acid, 6-hydroxykynurenic acid (6HKA), p-hydroxybenzoic acid (PHBA), hydroxycinnamic acid, and caffeic acid] in Ginkgo biloba extracts (GBEs) by HPLC wavelength switching method was established, and its quality was evaluated by statistical analysis. Methods: An Inertsil ODS-3 C18 column (250 mm×4.6 mm, 5 μm) was used with a column temperature of 40 ℃ and a mobile phase gradient of acetonitrile-0.4% phosphoric acid. The detection wavelengths were 220 nm [shikimic acid, catechinic, (-)-epicatechin], 254 nm (gallic acid, protocatechuic acid, 6HKA, PHBA), 310 nm (hydroxycinnamic acid, caffeic acid), respectively. Results: Remarkable differences were found among the nine compositions in different producing areas samples. The samples from different manufacturers showed significant difference in organic acid compounds. There were great difference of the contents of organic acid in various batches from different manufacturers. The data were processed through unsupervised principal component analysis (PCA), cluster analysis (CA), correlation, and regression analysis to compare the quality differences. Catechinic, gallic acid, protocatechuic acid, and 6HKA were recognized as characteristic chemical markers that contributed most to reflect the difference between samples, and there were internal relations among these compounds. Conclusion: The established method was simple, accurate, and reliable with good precision, repeatability and stability, which can be used for the simultaneous determination of nine organic acid compounds. Through multivariate statistical analysis, the Q-markers that may affect the difference of GBEs were better identified, which can lay the foundation for the comprehensive quality control of GBEs. Meanwhile, the extracting process of GBEs were not uniform. The stability of process parameter in the enterprise was prepared to be further enhanced.