Application of multifold characteristic ion filtering combined with statistical analysis for comprehensive profiling of chemical constituents in anti-renal interstitial fibrosis I decoction by ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap high resolution mass spectrometry

A Chinese herbal formula of Anti-Renal Interstitial Fibrosis I Decoction (ARIF I) is composed of Eucommia ulmoides Oliv., Scutellaria baicalensis Georgi, and Rheum. officinale Baill., and it has been used for the treatment of chronic kidney disease for many years. However, the comprehensive chemical analysis of the formulated ARIF I has yet to be clarified. In this study, an ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap high resolution mass spectrometry (UHPLC/Q-orbitrap HRMS) method executed in full scan/data-dependent MS² (full MS/dd-MS²) mode has been established in negative ion mode to analyze the major chemical constituents in ARIF I as well as in its three constituent herbs. To rapidly and efficient identify these compounds, we employed a combination of statistical analysis of the MS² data and fragmentation pathway method to screen for elementary characteristic ions and sub-characteristic ions. Then, we applied multifold characteristic ion filtering to comprehensively profile ARIF I extract chemical constituents with diverse structures. A total of 360 compounds, including anthraquinones, sennosides, galloyl glucoside derivatives, catechin and its derivatives, flavonoids, iridoids, phenylpropanoids, lignan, organic acid, and other compounds were rapidly identified or tentatively characterized by multifold characteristic ion filtering based on their accurate mass spectra (within 5 ppm error) and structure types or by comparison with reference standards. All the ARIF I compounds were also detected in the individual constituent herbs. This study provides a basis for further pharmacokinetic studies of ARIF I and may help in the discovery of new chemical drugs to treat chronic kidney disease. This study also provides a more efficient approach for the screening of appropriate characteristic ions, and a practical strategy for the detection of the types of compounds identified in this study in other herbal medicines.