title: Increase in antioxidant effect of ginsenoside Re-alanine mixture by Maillard reaction.
abstract: Ginsenoside Re, one of the major triol type ginsenosides contained in Panax ginseng, has a hydrophobic four-ring steroid-like structure with hydrophilic sugar moieties at carbon-3 and -20. The aim of the present study was to identify the changes in structure and antioxidant activity of ginsenoside Re by the Maillard reaction, which has not been reported yet. The free radical-scavenging activity of ginsenoside Re-alanine mixture was increased by heat-processing. Ginsenoside Re was gradually changed into Rg(2), Rg(6) and F(4) by heat-processing, and the glucosyl moiety at carbon-20 was separated. The improved-free radical-scavenging activity by heat-processing was mediated by the generation of antioxidant Maillard reaction products (MRPs). Antioxidant MRPs were generated from the reaction of glucose and alanine. Based on the viability results of LLC-PK1 renal epithelial cells, MRPs and less-polar ginsenosides contributed to the combined renoprotective effect against oxidative renal damage. Maillard reaction is importantly involved in the increased antioxidant effect of ginsenoside by heat-processing.
authors.affiliation: Natural Medicine Center, Korea Institute of Science and Technology, Gangneung 210-340, Republic of Korea.
authors.forename: Woojung
authors.initials: W
authors.lastname: Lee
authors.forename: Soon-Hye
authors.initials: SH
authors.lastname: Park
authors.forename: Seungyong
authors.initials: S
authors.lastname: Lee
authors.forename: Bong Chul
authors.initials: BC
authors.lastname: Chung
authors.forename: Min Ok
authors.initials: MO
authors.lastname: Song
authors.forename: Kyung Il
authors.initials: KI
authors.lastname: Song
authors.forename: Jungyeob
authors.initials: J
authors.lastname: Ham
authors.forename: Su-Nam
authors.initials: SN
authors.lastname: Kim
authors.forename: Ki Sung
authors.initials: KS
authors.lastname: Kang
mesh_terms: D000409:Alanine / Q000737:chemistry* / Q000494:pharmacology; D000818:Animals; D000975:Antioxidants / Q000737:chemistry* / Q000494:pharmacology; D002460:Cell Line; D036145:Ginsenosides / Q000737:chemistry* / Q000494:pharmacology; D006358:Hot Temperature; D007668:Kidney / Q000378:metabolism; D018374:LLC-PK1 Cells; D015416:Maillard Reaction; D018384:Oxidative Stress / Q000187:drug effects; D005894:Panax / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology; D013552:Swine
chemical_list: D000975:Antioxidants; D036145:Ginsenosides; D010936:Plant Extracts; C049864:ginsenoside Re; D000409:Alanine