IN-VITRO LOUSCIDAL AND ACARICIDAL ACTIVITIES OF ALKALOID OF CALPURNIA AUREA EXTRACTS AGAINST LINOGNATHUS OVILLUS AND AMBLYOMMA VARIEGATUM

The study was designed to evaluate the louscidal, and acaricidal activities of alkaloids of Calpurnia aurea leaves extracts. Alkaloid of C. area leaves extract at concentrations of 200, 100, 50, 25, 12.5 and 6.25 mg/ml were used for in-vitro adult immersion test of ticks and lice, which they were monitored for their mortality rates for 24 h. The activities of test substances were evaluated against Amblyomma variegatum and Linognathus ovillus, and compared with diazinon 60 EC. After 24 h post exposure, two higher concentrations of 200 and 100 mg/ml of the alkaloid extract caused 100 ± 0.5% and 100 ± 0.6% lice mortality, and 100 ± 0.33 and 93.3 ± 0.33 tick mortality respectively. The alkaloid extract showed an insignificant difference in its acaricidal and louscidal activity when compared to the Diazinon 60EC at the same concentration (P>0.05). LC₅₀ and LC₉₀ values (with 95% confidence limits) of the alkaloid of C. aurea for lice and tick were estimated 9.08 mg/ml (6.21-13.47), 17.65 mg/ml (11.71-22.49) and mg/ml 16.69 (11.77, 26.64), 31.69 mg/ml (21.25-50.72), respectively. Dose-response data of C. aurea alkaloid extract on L. ovillus and A. variegatum indicated the gradual increase in the mortality pattern with slopes of 3.1188, and 3.2321, and R² values of 0.9702 and 0.9882 suggesting that 97.02, 98.82% data were correlated with log concentration, respectively.  The results obtained in this study indicate that the alkaloid extract of C. aurea has promising louscidal and acaricidal activities, lending support for further investigation of the plants to isolate the active components.