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Updated: Jul 11, 2026

Microwave-Assisted Extraction of Phenolic Compounds and Antioxidants for Cosmetic Applications Using Polyol-Based Technology
Published on: August 23, 2024
Phenolic derivatives with free-radical-scavenging activities from Ixeridium gracile (DC.) Shih
Xue-Mei Ma1, Yong Liu, Yan-Ping Shi
1Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, PR China.
Abstract:
Phytochemical investigation of the Tibetan medicinal plant Ixeridium gracile resulted in the isolation and identification of twelve flavonoids and two coumarins, compounds 1-14, the dimeric '2alpha,3alpha-epoxy-5,7,3',4'-tetrahydroxyflavan-(4beta-->8)-epicatechin' (1) being a new constituent. The free-radical-scavenging potentials of different extract fractions as well as of the pure compounds towards the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical were evaluated, and are discussed in terms of structure-activity relationship (SAR). The flavonoids were found to be the major constituents contributing to the free-radical-scavenging activity of I. gracile, but the high concentration of coumarins additionally contributed to the observed activity.
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