Open AccessAntioxidant Activity of Natural Samwirin A: Theoretical and Experimental Insights
Author(s) -
Thuc Dinh Ngoc,
Mai Vu Thi Ha,
Thanh Nguyen Le,
Thi Van Anh Nguyen,
Ádám Mechler,
Nguyễn Thị Hòa,
Quan V. Vo
Publication year - 2021
Publication title -
acs omega
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.779
H-Index - 40
ISSN - 2470-1343
DOI - 10.1021/acsomega.1c04569
Subject(s) - hydroperoxyl , trolox , chemistry , antioxidant , scavenger , scavenging , reaction rate constant , aqueous solution , aqueous medium , electron transfer , biochemistry , biophysics , stereochemistry , organic chemistry , antioxidant capacity , radical , kinetics , biology , physics , quantum mechanics
Samwirin A ( SW ), a natural compound isolated from Sambucus williamsii or Rourea harmandiana , is known to exhibit potent antiosteoporosis activity and promote cell proliferation in rat osteoblast-like UMR 106 cells. Antiosteoporosis activity suggests that the compound must also exhibit antioxidant activity but this has not been studied thus far. In the present study, the antioxidant activity of SW was examined by experimental and computational studies. It was found that SW exhibits good hydroperoxyl scavenging activity, particularly in water at physiological pH ( k overall = 1.01 × 10 7 M -1 s -1 ). The single-electron transfer mechanism defines the HOO • + SW reaction in water, while the activity in the lipid medium is moderate and it follows the formal hydrogen transfer mechanism. The rate constant of the HOO • scavenging reaction in the aqueous solution is about 78 times higher than the reference compound Trolox. The computational results are in line with experimental data underscoring that SW is a promising radical scavenger in aqueous media at physiological pH.