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Semi-Targeted Ultra-High-Performance Chromatography Coupled to Mass Spectrometry Analysis of Phenolic Metabolites in Plasma of Elderly Adults
Published on: April 22, 2022
Stereospecificity in hydroxyl radical scavenging activities of four ginsenosides produced by heat processing
Ki Sung Kang1, Hyun Young Kim, Noriko Yamabe
1Institute of Natural Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
Abstract:
The activity-guided fractionation of sun ginseng (SG, heat processed Panax ginseng C. A. Meyer at 120 degrees C) was carried out to identify its main active hydroxyl radical (*OH) scavenging components. As a result, the n-BuOH fraction mainly consisting of ginsenosides showed the strongest activity. Of several ginsenosides of SG, the *OH scavenging activities of relatively high contents of 20(S)-Rg(3), 20(R)-Rg(3), Rk(1), and Rg(5) were compared. Rg(5) and 20(S)-Rg(3) showed strong *OH scavenging IC(50) values of 0.15 and 0.44 mM, respectively, and these activities were prominently higher than each of their respective isomers. Therefore, stereospecificity exists in the *OH scavenging activities of ginsenosides produced by heat processing. Especially, the double bond at carbon-20(22) or the OH group at carbon-20 geometrically close to OH at carbon-12 is thought to increase the *OH scavenging activity of ginsenosides.
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