ABSTRACT
Objective: The effects of different decoction time and different decoction temperature on its chemical constituents of anthraquinones, anthrone, and tannins were revealed by pseudo-targeted metabolomics, which provided the basis for clinical use of rhubarb. Methods: Using LTQ-Orbitrap-MSn to accurately excavate the characteristic ions of various chemical components of rhubarb, the ion pairs of chemical components were determined as much as possible by characteristic ions to obtain the peak area of various components by using the MRM mode of QQQ-MS. The effects of different decoction methods on the chemical components of rhubarb was compared by multivariate statistical analysis combined with paired t test. Results: Both decoction time and decoction temperature have impacts on the chemical components of rhubarb decoction. Short-term decocting for 15 min was beneficial to the dissolution of dianthrone glycosides and anthraquinone glycosides, while long-term decocting for 60 min was beneficial to the dissolution of tannins; Compared with boiling water maceration, boiling water decoction was more favorable for the dissolution of anthraquinones and tannins. Conclusion: This paper adopts the method of pseudo-targeted metabolomics, and clearly points out that short-term decocting or maceration is conducive to exerting the laxative effect of rhubarb, and long-time boiling decocting is conducive to exerting clearing heat and detoxifying efficacy, which provides a reference for the clinical application of rhubarb.
ABSTRACT
A simple, specific and selective quantitative analysis of multi-components by single marker(QAMS) method for simultaneous determination of anthraquinones and anthraquinone glycosides in Polygonum multiflorum was developed. Four main anthraquinones and its glycosides, emodin, emodin-8-O-β-D-glucoside, physcion and physcion-8-O-β-D-glucoside were selected as analytes to evaluate the quality of P. multiflorum. Emodin was used as the internal standard, and the relative correction factors(RCFs) between emodin and the other three anthraquinones were calculated. Comparison of the contents of the four components in 30 batches of P. multiflorum from different regions and 12 batches decoction pieces from different manufacturers by QAMS and external standard method(ESM) showed that there was no significant difference between QAMS and ESM for quantification of the four main components by using relative error results, and the QAMS method was accurate and reliable, and had a good repeatability. In addition, compared with the results calculated by the difference method between total anthraquinone and free anthraquinone in the content determination of P. multiflorum in Chinese Pharmacopoeia, the results of direct determination combined anthraquinone by QAMS were very close to that by measured the external standard method. Therefore, simultaneous quantification of four main anthraquinones by using QAMS is suitable to evaluate the quality of P. multiflorum. Then the optimized assay method of the combined anthraquinone contents showed simple and feasible, which could be replaced and improved the quantification method of the combined anthraquinone in the current Chinese Pharmacopeia.