UPLC-Q-TOF-MS/MS Analysis of Chemical Components of Polyphenols in Herba Sophorae
Mesona chinensis Benth. is a herb of the genus Mesona of Labiatae, distributed in northeast India, southeast Asia, Taiwan, China, Fujian, Guangdong, Guangxi and Yunnan of China. As a traditional Chinese medicine, Liangfen Grass is known as the “fairy grass” and has the effects of astringency, sweetness, coldness, heat clearing, blood cooling, and detoxification. It has been developed into food, natural health products, and even clinical drugs. Existing research has shown that its roots, stems, leaves, and flowers contain a large amount of bioactive substances, including polysaccharides, flavonoids, terpenes, vitamins, and phenols, which have high nutritional and medicinal value.

Phenolic compounds play an important role in plant growth and have strong protective effects on various organs of the human body. According to reports, scholars have found through research that liangfen grass contains hypoglycemic and hypertensive substances, including β – sitosterol, stigmasterol, α – and β – amyloid proteins, oleanolic acid, aristolochic acid, and β – sitosterol glycosides. At the same time, scholars have identified nine active compounds from the water extract of liangfen grass, including kaempferol, apigenin, caffeic acid, protocatechuic acid, eugenic acid, vanillic acid, p-hydroxybenzoic acid, oleanolic acid, and ursolic acid. Among them, caffeic acid, protocatechuic acid, and kaempferol are considered important components of the antioxidant activity of liangfen grass, including reducing LDL oxidation and inflammation, thereby providing protection against cardiovascular disease.

Ultra high performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) technology has the advantages of high sensitivity, high resolution, high separation efficiency, and short analysis time. At the same time, it can also obtain information on the molecular weight, elemental composition, and ion fragments of compounds, which can quickly determine the structure of compounds. It has been widely used in the field of drug analysis. At present, the composition of polyphenols in Sophora japonica is not fully understood. In this experiment, UPLC-Q-TOF-MS/MS technology was used to rapidly and comprehensively qualitatively analyze the chemical components in Sophora japonica, providing important reference for the study of phenolic chemical components in Sophora japonica.

This study established a UPLC-Q-TOF-MS/MS method for analyzing the polyphenolic components of Sophora japonica. By analyzing the mass spectrometry raw data, including relative molecular weight, retention time, elemental composition, fragment ions, and other information, combined with reference standards, databases, and literature reports, 51 compounds were identified and speculated. It was confirmed that the polyphenolic components of Sophora japonica were mainly composed of flavonoids, phenylpropanoid acid, and their oligomers, including caffeoyl hexoside, salvianolic acid F, and salvianolic acid H apigenin-6,8-di-C-hexoside、 Chuanchenpi extract, nobiletin-3-O – β – D-glucoside, 20-deoxysalvianolic acid, 3-O-D-glucopyranosyl platydigenin methyl ester, and marstenacigenin A have not been reported in relevant literature on Chinese herbal medicine. This study suggests that these nine compounds have been discovered for the first time in Chinese herbal medicine. The research results lay the foundation for the basic research and development of effective substances in herbal medicine, and have important guiding significance for the further development of new drugs.