Pharmacological screening of Hypericum androsaemum extracts for antioxidant, anti-lipid peroxidation, antiglycation and cytotoxicity activity

Oxidative stress and glycation processes have a combined effect on diabetes related complications. Crude plant extracts and plant derived compounds possessing both antiglycation and antioxidant activities have a high therapeutic potential for treating these complications. Antioxidant, antiglycation, anti-lipid per oxidation and cytotoxic activities of crude methanol extract and solvent fractions of Hypericum androsaemum L. (Hypericaceae) were evaluated and correlated with total content of phenolics and flavonoids. Significant radical scavenging activity was observed for the methanol extract against 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical used as a basis for antioxidant activity with IC50 value of 92.70±2.85 µgmL-1 (96.20±2.34% inhibition at 500µgmL-1). In case of anion scavenging activity the results were not very significant (33.20±1.22% inhibition at 500µgmL-1). Anti-lipid per oxidation activity was highest for n-hexane fraction (67.83±1.33% inhibition at 500µgmL-1) while the ethyl acetate fraction had the highest antiglycation activity (62.77±2.54% inhibition at 500µgmL-1). Statistically significant correlation was determined for antioxidant and antiglycation activity and phenolic and flavonoid contents. In cytotoxicity assay all the extracts had IC50 values >30µg mL-1 as compared to the standard cycloheximide (IC50 value 0.084±0.1 µgmL-1). The polar extracts of H. androsaemum can be a good source of non-toxic compounds with antioxidant, anti-lipid per oxidation and antiglycation activities.