Antidiarrhoeal and antibacterial activity of aqueous and methanolic leaves extracts of Dissotis thollonii Cogn. (Melastomataceae)

• Published in: Asian Pacific Journal of Tropical Biomedicine
• Main Authors: Ateufack Gilbert, Tadjoua Tchoumbou Herve, Yousseu Nana William, Sama Fonkeng Leonard, Kuiate Jules-Roger, Kamanyi Albert
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wolters Kluwer Medknow Publications 2014
• Subjects: Antidiarrhoeal; Antibacterial; Phytochemical test; Dissotis thollonii; Arctic medicine. Tropical medicine; RC955-962; Biology (General); QH301-705.5; Arctic
• Online Access: https://doi.org/10.12980/APJTB.4.201414B214; https://doaj.org/article/a710a33f064540e5b2223e0a47e8d760

Objective: To investigate the phytochemical test and selected pharmacological activities (antidiarrhoeal and antibacterial activity) of the aqueous and methanolic leaves extracts of Dissotis thollonii Cogn. (Melastomataceae) (D. thollonii). Methods: The aqueous and methanolic extracts were evaluated for their antibacterial activities on the in vitro growth of 2 clinical isolates (Staphylococcus aureus and Shigella flexneri), and 5 reference bacteria strains [Escherichia coli ATCC 8739 (E. coli), E. coli ATCC 10536, Salmonella typhi ATCC 6539, Enterobacter aerogenes ATCC 13048 and E. coli ATCC 11775] by determining the minimum inhibitory concentrations (MICs) and bactericidal concentrations using broth microdilution method as well as on the infectious, secretory and osmotic induced diarrhoea models in rats. Results: The aqueous extract inhibited the in vitro growth of all bacteria tested (the 05 reference bacteria strains and the 02 clinical isolates), with MICs values comprised between 32 and 512 μg/mL, whereas the methanolic extract has done the same with the MICs values located between 128 and 512 μg/mL. In vivo, the methanolic and aqueous extracts provoqued at all doses, a significant decrease (P<0.001) in the bacterial load in the faeces of rats, 6 and 7 d of treatment respectively. Infected animals relatively lost weight when treated with the aqueous extract but it remained constant for those treated with the methanolic extract. The results also showed that, the aqueous and methanolic leaves extracts of D. thollonii had, after 6 h of observation, significantly (P<0.001) inhibited in vivo, diarrhoea induced experimentally by castor oil and magnesium sulphate, particularly by prolonging the latency time, reducing the water content of faeces, the frequency of defecation and the number of wet defecation as compared to the negative control which received distilled water and the animals having received 2.5 mg/kg of loperamide used as reference substance. The phytochemical assay revealed the presence of ...