Comparison on chemical constituent changes of gallnut fermented Chinese gall leaven by HPLC fingerprint / 中草药

ABSTRACT

Objective To study and establish the HPLC fingerprint standard for the quality analysis and compare effects on the chemical composition of gallnut by ferment of Chinese gall leaven. Methods The fingerprint of Chinese gall leaven was built by Waters Symmmetry ShieldTM RP18 (250 mm × 4.6 mm, 5 μm) C18 column, and acetonitrile-0.1% trifluoroacetic acid aqueous in gradient as mobile phase, the flow rate was 0.8 mL/min, and the detecting wavelength was set at 280 nm. The chemical fingerprint similarity of 10 batches of Chinese gall leaven was calculated with the Chromap Chromafinger 2005 beta 0.1 standard substance comparison and HPLC-MS were adopted to identify the common peaks. Results The fingerprint chromatography for the 10 batches of Chinese gall leaven included 10 common peaks, with a good separation at each peak. The relative retention time for common peaks of each batch was less than 1.0%, and the similarities among 10 samples were greater than 0.90. Gallic acid (peak 1), (-)-epigallocatechin (EGC, peak 2), methyl gallate (peak 3), ethyl gallate (peak 5), epigallocatechin gallate (EGCG, peak 6), 2,4,6-tri-O-galloyl-β-D-glucose (peak 7), and 2,4,6-tri-O-galloyl-α-D-glucose (peak 9) were identified. The gallnut fermented made the content of gallic acid and 2,4,6-tri-O-galloyl-α-D-glucose increased and the contents of methyl gallate, ethyl gallate, and (-)-epigallocatechin gallate decreased. It was found that (-)-epigallocatechin and 2,4,6-tri-O-galloyl-β-D-glucose had formed in the process for the first time. Conclusion The processing mechanism of Chinese gall leaven is related to gallnut fermentation process change and create new chemical composition and fingerprint can be used to monitor the quality of fermentation processing of Chinese gall leaven.