Anti-leishmanial, anti-inflammatory and antioxidant potential of Omphalocarpum ahia A. Chev

Omphalocarpum ahia A.Chev. is an evergreen medium-sized tree, about 30 m tall, and exudes a whitish fluid from the incised bark. It is used in folklore medicine for the treatment of pain, inflammation, bacterial and parasitic diseases. Reports of its pharmacological activities are not widespread. This study sought to evaluate its antileishmanial, anti-inflammatory and antioxidant potential. Its anti-leishmanial activity in comparison to Amphotericin B was evaluated in vitro against promastigote forms of Leishmania donovani using a hemocytometer counting chamber and a high field microscope with mobility of the parasite as a marker of cell viability. The extract was tested at concentrations between 15.6-500 μg/mL. The anti-inflammatory activity of the extract was evaluated using the carrageenan-induced foot edema in chicks whereas the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay was used for the antioxidant evaluation. O. ahia showed a lower anti-leishmanial activity (IC50=124.0±0.67 μg/ml) than the standard drug amphotericin B (2.4± 0.67 μg/ml). It also showed moderate anti-inflammatory activity (ED50=75.9±0.667 mg/kg BDW) compared to diclofenac (ED50=3.74±0.333). The radical scavenging activity of O. ahia was just three times less potent than Vitamin E used as positive control. These activities may be due to the presence of tannins, glycosides, saponins, terpenoids and phytosterols found in the phytochemical analysis of the plant. Thus from the observed activity, barring any toxicity issues, O ahia may be harnessed and integrated into the treatment of leishmanias is caused by L. donovani as it may present a cheaper and safe alternative to the toxic synthetic analogues.