Radical Scavenging Activities of Lagerstroemia speciosa (L.) Pers. Petal Extracts and its hepato-protection in CCl4-intoxicated mice

BACKGROUND Lagerstroemia speciosa (L.) Pers. has medicinal importance. Bioactive phytochemicals isolated from different parts of L. speciosa, have revealed hypoglycemic, antibacterial, anti-inflammatory, antioxidant and hepato protective properties. Despite one report from Philippines detailing the use of L. speciosa as curative for fever and as well as diuretic, there is no experimental evidence about the hepatoprotective activity of the flower extracts. METHODS Several spectroscopic methods, including GC-MS, were used to characterize phytochemicals present in the petal extract of L. speciosa. Ethanol extract of petals was evaluated for anti-oxidant and free radical scavenging properties by using methods related to hydrogen atom transfer, single electron transfer, reducing power, and metal chelation. This study has also revealed the in vitro antioxidant and in vivo hepatoprotective properties of petal extract against carbon tetra chloride (CCl4)-induced liver toxicity in Swiss albino mice. Hepatoprotection in CCl4 -intoxicated mice was studied with the aid of histology and different enzymatic and non-enzymatic markers of liver damage. Cytotoxicity tests were done using murein spleenocytes and cancareous cell lines, MCF7 and HepG2. RESULT GCMS of the extract has revealed the presence of several potential antioxidant compounds, of them γ-Sitosterol and 1,2,3-Benzenetriol (Pyrogallol) were the predominant ones. The antioxidants activities of the flower-extract were significantly higher than curcumin (in terms of Nitric oxide scavenging activity; p = 0.0028) or ascorbic acid (in terms of 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) assay; p = 0.0022). The damage control by the flower extract can be attributed to the reduction in lipid peroxidation and restoration of catalase activity. In vitro cytotoxicity tests have shown that the flower extract did not affect growth and survivability of the cell lines. It left beyond doubt that a flower of L. speciosa is a reservoir of antioxidant and hepatoprotective agents capable of reversing the damage inflicted by CCl4-intoxication. CONCLUSION Results from the present study may be used in developing a potential hepato-protective health drink enriched with antioxidants from Lagerstroemia speciosa (L.) Pers.