Semiquinone glucoside derivative (SQGD) isolated from Bacillus sp. INM-1 protects against gamma radiation-induced oxidative stress

• SQGD inhibits γ radiation-induced in vitro toxicity.
• SQGD inhibits radiation-induced carbonylation in proteins.
• SQGD protects enzymes against radiation-induced inactivation.
• SQGD protect DNA from radiation-induced damage.
• SQGD protects lipid peroxidation in brain, intestine and liposomal membrane.

In the present study, radioprotective potential of Semiquinone glucoside derivative (SQGD) isolated from radioresistant bacterium Bacillus sp. INM-1 was evaluated. γ-Radiation induced protein carbonylation, plasmid DNA damage, enzyme functional impairment, lipid peroxidation, HO radicals generation and their protection by SQGD was assessed. As a result of SQGD treatment, significant inhibition (p < 0.05) in protein carbonylation was observed with BSA. SQGD treatment was found to restore supercoiled (∼70 ± 3.21%) form of irradiated plasmid DNA against γ-irradiation. SQGD protects enzymes (EcoR1 and BamH1) against radiation-induced dysfunctioning. SQGD significantly inhibited (p < 0.05) lipid peroxidation in liposomes, brain and liver homogenate. Higher HO
• radicals-averting activity of SQGD was observed in the serum and liver homogenate of C57BL/6 mice against H2O2-induced oxidative stress. In conclusion, SQGD demonstrates excellent radical-scavenging activity towards bio-macromolecules in irradiated environment and can be developed as an ideal radioprotector against radiation-induced oxidative stress in future.