In vitro Anti-leishmanial Activity of Polygonum glabrum Stem Extract on Leishmania tropica (KWH23) Strain

Abstract

Aims: The aim of current study is to evaluate the Polygonum glabrum aqueous extract for anti-leishmanial activity, with the hope to find less expensive and common drug for this neglected disease. Study Design: In vitro Susceptibility of Leishmania tropica. Place and Duration of Study: After Polygonum glabrum collection from District Mardan, further work was carried out in Parasitology Laboratory, Quaid-i-Azam University Islamabad, Pakistan from May 2013 to October 2013. Methodology: Soxhlet apparatus was used for plant extraction followed by rotary evaporator to remove the solvent. Various concentrations of the plant extract were made. The flat bottoms 96 well ELISA plate was used for antileishmanial assay, amphotericin B was taken as positive control. The morphology and number of the promastigotes were monitored after each 24 hours. The LC50/90 was calculated using SPSS version 21. Results: After 72 hours of incubation at 25±ºC promising results were shown by P. glabrum. The percent mortality recorded at different concentration (0.05 ug/ml, 0.5 ug/ml, 5 ug/ml, 50 ug/ml, and 500ug/ml) were (4.23±0.68, 19.16±0.56, 40.5±0.05, 68.1±0.76 and 100±0.00%) respectively. The LC50, LC90 and R2 values find out for the assay were 7.25 ug/ml, 227.4ug/ml and 0.97 ug/ml. In comparison, the percent mortality shown by amphotericin B were 30.27±0.54, 45.12±1.10, 80.87±1.78, 100±0.00 and 100±0.00 with 0.35 ug/ml, 9.49 ug/ml and 0.91 values of LC50, LC90 and R2 respectively. The negative control has zero mortality. Conclusion: The current investigation reveals that Polygonum glabrum extract possess activity against Lesihmania tropica. As crude form of P. glabrum extract showed promising antileishmanial results, P. glabrum and other members of the family need further investigation so that the pure bioactive antileishmanial compounds should be isolated with cost effective, promising results and less side effects.