Phytochemical analysis, in vitro antioxidant and in vivo anti-inflammatory activities of a hydroethanolic extract of Zingiber officinale Roscoe rhizome

Abstract

This present study aims to evaluate the in vitro antioxidant and the in vivo anti-inflammatory activities of the ethanolic extract of Zingiber officinale Roscoe rhizome. The extract is obtained by maceration (80 %). The analysis of total phenolic and flavonoid contents showed that the ethanolic extract is rich in polyphenols (206.95 ± 11.78 µg equivalent gallic acid) and flavonoids (11.62 ± 0.00 µg equivalent quercetin/mg dry extract). According to the 1-diphenyl-2-picrylhydrazyl assay, the ethanolic extract exhibitsan important antioxidant activity with an IC50 of 0.11 ± 0.00 mg/ mL. Furthermore, the ethanolic extract demonstrates a higher reducing power compared to the butylated hydroxytoluene, with IC50 values of 0.01 ± 0.00 mg/mL. The ethanolic extract shows the highest inhibition in the β-carotene assay, with an inhibition of 82 %. The two induced inflammation tests, Xylene-Induced Ear Edema and Carrageenan-Induced Paw Edema, showed that the ethanolic extract of Zingiber officinale produced a remarkable anti-edematous effect, with a dose of 400 mg/kg for Xylene-Induced Ear Edema and a dose of 200 mg/kg for Carrageenan-Induced Paw Edema. In conclusion, the rhizome extract of Zingiber officinale has demonstrated both antioxidant and anti-inflammatory properties, as can be justified by its traditional uses.