Context Manilkara zapota (L.). P. Royen. (Sapotaceae) has been used in folk medicine to treat pain, diarrhoea, inflammation, arthralgia, and other disorders. Objective Screening of Manilkara zapota leaves ethanol extract and its different solvent soluble fractions for possible antinociceptive and antidiarrhoeal activities in Swiss albino mice. Materials and methods The extract and various fractions (200 and 400 mg/kg body weight; p.o.) were tested for peripheral and central antinociceptive activity by acetic acid-induced writhing and radiant heat tail-flick method, respectively; castor oil-induced diarrhoeal model was used to evaluate antidiarrhoeal activity at both doses. All the samples were administered once in a day and the duration of study was approximately 5 h. Results Ethanol extract (400 mg/kg), petroleum ether fraction (400 mg/kg), and ethyl acetate fraction (400 mg/kg) showed significant peripheral antinociceptive activity having 59.89, 58.24, and 46.7% (p < 0.001) of writhing inhibition, respectively, which is comparable with that of standard diclofenac (59.34% inhibition). The ethanol extract (400 mg/kg) and petroleum ether fraction (400 mg/kg) also showed promising central analgesic activity having 74.15 and 82.15% (p < 0.001) elongation of reaction time, respectively, at 90 min after administration of sample which is also similar to that obtained by morphine (85.84% elongation). In antidiarrhoeal activity screening, ethanol extract (200 and 400 mg/kg) showed significant inhibition of defecation by 53.57 and 60.71%, respectively (p < 0.001) compared with that of loperamide (71.42%). Discussion and conclusion The findings of the studies demonstrated antinociceptive and antidiarrhoeal activities of M. zapota leaves which could be the therapeutic option against pain and diarrhoeal disease.
Keywords: Acetic acid; castor oil-induced diarrhoea; percent (%) time elongation; radiant heat; tail-flick; writhing inhibition.