Antihemolytic Activity of Clerodendrum viscosum Vent. is Mediated by its Antioxidant Effect

Abstract

Aims: The objective of this study was to evaluate the protective effect of polar extract of Clerodendrum viscosum vent. against in vitro hemolysis of human erythrocytes and its association with the antioxidant activity of C. viscosum. Study Design: Extraction of C. viscosum dried root, in vitro antihemolytic activity assay, lipid peroxidation assay, phytochemical analysis, estimation of polyphenols and flavonoids. Place and Duration of Study: Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Dhaka, Bangladesh, between January 2011 and May 2011. Methodology: C. viscosum polar extract-pretreated erythrocytes were hemolysed by hypotonia and oxidizing agent, H2O2. The liberated hemoglobin was determined as a measure of hemolysis. Total reducing power and 2,2-diphenyl-1-picrylhydrazyl (DPPH)-free radical scavenging activity of extract were compared with those of vitamin C. Anti-lipid peroxidation activity of C. viscosum polar extract also was determined by exposing rat brain cortex tissue to Fenton's reagent (H2O2+FeSO4)- induced oxidative stress. Then C. viscosum extract was subjected to estimation of total polyphenols and total flavonoids following qualitative phytochemical analysis. Results: C. viscosum polar extract significantly inhibited in vitro hemolysis. Total reducing power and DPPH-radical scavenging activity were higher than those of vitamin C. In cortical tissue homogenate, C. viscosum polar extract significantly reduced (~38%) the levels of lipid peroxides (LPO). Phytochemical analysis revealed the presence of substantial amount of polyphenols, flavonoids and other antioxidant chemicals in the extract. Conclusion: Present investigation demonstrates that antihemolytic activity of C. viscosum polar extract is mediated by its antioxidant effect.