Assessment of macrofilaricidal activity of leaf extracts of Terminalia sp. against bovine filarial parasite Setaria cervi

Antifilarial potential of three medicinal plants namely, Terminalia bellerica, Terminalia chebula and Terminalia catappa was explored using Setaria cervi, a bovine filarial parasite at concentrations of 2.5, 5 and 10 mg/ml. Amongst all the extracts, methanol extract of T. bellerica showed highest macrofilaricidal activity i.e. 84.63 ± 1.11 at 10 mg/ml in MTT reduction assay with IC50 value of 2.7 mg/ml. which was better than the standard DEC i.e. 79.22 ± 3.1% at 10 mg/ml with IC50 value 2.84 mg/ml. Other plant extracts showed mild in vitro macrofilaricidal activity. T. bellerica methanol extract exhibited significant GST activity of 18.86 ± 0.21 and 12.83 ± 0.03 μM/ml/min at 5 and 10 mg/ml with percentage inhibition value of 73.96% and 82.29% respectively. DEC showed GST activity value of 40.03 ± 4.14 and 21.48 ± 6.44 μM/ml/min with percentage inhibition value of 21.76% and 58.01% at 5 and 10 mg/ml respectively. Thus, methanol extract of leaves of T. bellerica exhibited highly significant antifilarial potential and needs detailed analysis.