Evaluation of Antinociceptive, Antidiarrheal and Antimicrobial Activities of Leaf Extracts of Clerodendrum indicum

Abstract

Introduction: The methanolic extracts and its different partitioning fractions of leaves of Clerodendrum indicum were evaluated for their anti-nociceptive, anti-diarrheal and in vitro antimicrobial activities. Methods: The anti-nociceptive activity was evaluated using the acetic acid-induced writhing test in mice; the anti-diarrheal activity was investigated by the effect of extracts on castor oil-induced diarrhea while the in vitro antimicrobial activities were examined by the disc diffusion method. Results: In the acetic acid-induced writhing test, the methanolic extract at a dose of 200 and 400 mg/kg showed a significant (p<0.001) and dose-dependent reduction in the number of writhes with 62.57% and 70.76% of inhibition, respectively, while the CCL4 fraction at the same dose showed potent anti-nociceptive activity (p<0.001) with 73.09% of inhibition of writhing which was even higher than that of standard diclofenac sodium (55.56% inhibition). The methanolic extract, CCL4 and chloroform fraction showed moderate activity against the tested microorganisms in terms of both zones of inhibition (ranged from 9–13 mm, 10–13 mm and 10–13 mm, respectively, at a concentration of 400 µg/disc) and spectrum of activity. In castor oil-induced diarrhea testing, the methanolic extract and chloroform fraction at a dose of 400 mg/kg produced 21.74% and 26.96% inhibition of defecation, respectively, which were found to be comparable to that of standard drug loperamide (37.39% inhibition at 50 mg/kg ) with regard to the severity of diarrhea. Conclusion: The results of the investigation demonstrated that the methanolic extract and its different fractions of leaves of Clerodendrum indicum possess significant anti-nociceptive, antimicrobial and antidiarrheal activities.