Ionizing radiation impacts the powerful antioxidant activity of Zingiber officinale Rosc. extracts: in vitro study

Abstract

Certain herbs showed radio-protective against ionizing and non-ionizing radiation. Few studies investigated the effect of radiation on the polyphenols and flavonoids constituents of herbs. This study is aimed to investigate the effect of ionizing radiation (X-ray) on the certain constituents of Zingiber officinale Rosc. extracts taking in considerations the nature of preparation of extracts. Hydro-distilled, aqueous, ethanol and methanol extracts (1%) were prepared and exposed to X-ray radiation at dose rate of 1.9 Gy / min at room temperature. UV-visible scan of each extract was achieved and the physiochemical properties including pH, conductivity and total dissolved salts were determined for irradiated and non irradiated extracts. Biochemical testing including total polyphenolic compounds, total flavonoids, allantoin, and nitric oxide generation were also determined. Ionizing radiation resulted in disappearance of UV-peak at 277-278.5 nm and changes in the physiochemical properties of extracts that were related to the nature of extract. Total polyphenolic compounds were reduced in irradiated hydro-distilled, aqueous, and ethanol extracts while total flavonoids were reduced in all tested extracts. Allantoin level and the ability to donate nitric oxide were slightly improved by ionizing radiation. It concluded that the deleterious effects of ionizing radiation Zingiber officinale Rosc. extracts is depended on the nature of extract and on the nature of the constituents of each extract. Methanol extract is less affected by ionizing radiation compared with other extracts