Biotechnology and Biotech Industries Meet

Biography

Biography: Mawahib ElAmin Mohamed ElNour

Abstract

The present study aimed to investigate antioxidant activity, total phenolic and flavonoid contents of callus and rhizome extracts of Ginger (Zingiber officinale Rosc). The solvents used for extraction were petroleum ether and methanol:chloroform (1:1). Shoot tip was used as explants for callus induction. They were cultured on MS medium supplemented with different concentrations (0.00, 0.5, 1.00, 2.00 and 3.00 mg/l) of auxin 2,4-dichloro-phenoxyacetic acid (2,4-D). The highest mean of fresh weight of callus (p<0.05) was induced by 1.00 mg/l of 2,4-D (1.30±0.09) gm. Free radical scavenging activity was evaluated by DPPH method. The highest scavenging activity (p<0.05) was obtained from petroleum ether extract of rhizome (97.47±0.06%) followed by (methanol:chloroform) extract of rhizome (86.69±0.01%) and methanol:chloroform extract of callus (50.53±0.28%). Petroleum ether extract of callus demonstrated weak (p<0.05) antioxidant activity (41.23±0.01%). The total phenolic and flavonoid contents were estimated by Folin-Ciocaltue and aluminum chloride colorimetric methods sequentially. Highest phenolic contents were observed in (methanol:chloroform) extract of rhizome (58.10±0.1 mg/l), compared to petroleum ether of rhizome (10.28±0.12 mg/l) and (methanol:chloroform) extract of callus (7.1±0.17 mg/l). The amounts of total phenolic compounds were calculated as mg/l gallic acid equivalent of phenols. Flavonoid contents were detected to rhizome extracts using solvents (methanol:chloroform) and petroleum ether. The results obtained were (6.512±0.29 mg/l) and (1.841±0.20 mg/l) respectively. The amounts were calculated as mg/l quercetin equivalent of flavonoids. A positive correlation coefficients (R²) values were observed between total phenol and flavonoid content versus percentage inhibition of DPPH radical (R²=0.548) and (R²=0.666) respectively.