Anti-inflammatory, Antibacterial and Acaricidal Activities of Various Leaf Extracts of Bitter Apple, Citrullus colocynthis Schrad (Cucurbitaceae)

The present study involved the investigation of various leaf extracts of Citrullus colocynthis (bitter apple) viz. alcoholic, acetone and chloroform for their in vivo anti-inflammatory and in vitro antibacterial and acaricidal activities. For in vivo evaluation, doses of the extracts were taken as 50 mg/kg and 100mg/kg and for in vitro experiments, concentrations @5% and 10 % were used in the study. The antibacterial activity was studied against gram +ve (Staphylococcus aureus) and gram –ve (Escherichia coli) bacteria and was compared with standard drug (ampicillin). For anti-inflammatory activity; fifty rats were divided into 10 groups of five animals each. Initially the normal paw volumes of all the animals were noted down. All animals were injected in the sub-planter region of the right hind paw with 1% carrageenan (in normal saline) @ 0.1 ml to induce inflammation. The acaricidal activity of the alcoholic leaf extract was investigated by Adult immersion test against engorged adult females of Rhipicephalus microplus (Canestrini, 1888) (Acari: Ixodidae). No dose-dependent acaricidal activity of the extracts was demonstrated as there was no mortality of the ticks and absence of significant inhibition of oviposition by any of the concentrations of the extracts. Also the results revealed no significant antibacterial activity but all the extracts demonstated significant anti-inflammatory activity with maximum activity in alcoholic extract at higher concentration.