Chemical constituents and biological activities of different extracts from ginger plant (Zingiber officinale)

Background Ginger is widely used in traditional food and folk medicine. It was known to contain monoterpenoids, sesquiterpenoids, phenolic compounds and its derivatives as well as aldehydes, ketones, alcohols, and esters. The current work aims to evaluate the antioxidant and anticancer activities of different extracts from ginger peels and residues. Methods Ginger samples were collected from local market and extracted using water and ethanol solvent. Four different antioxidant assays were used (DPPH, ABTS, potassium permanganate and methylene blue), the anticancer activity was determined using HepG2 cell line and the active ingredients for the promising extract were identified using HPLC/UV. Results The obtained results recorded that hot water extract of ginger peels was the promising extract exhibiting promising antioxidant activity. Fractionation of this promising extract was achieved by silica gel column chromatography with petroleum ether/ethyl acetate as mobile phase. Six fractions were produced. Thin layer chromatography (TLCF254) was used for separation of active compounds and bioautography confirmed their antioxidant efficiency. Higher antioxidant activity and cytotoxicity against HepG2 cell line was recorded by fraction No. 4. Cold water extract of ginger peels exhibited comparatively higher antioxidant efficiency while both aqueous peel extracts showed antibacterial efficiency against four Gram-positive and Gram-negative bacterial strains using well diffusion assay. Conclusion Ginger peels hot water extract is the promising extract as antioxidant, antiradical, antibacterial and anticancer. Graphical Abstract