Pharmacodynamic and cytotoxicity effects of Syzygium cordatum {S Ncik, 48 (UZ)} fruit-pulp extract in gastrointestinal tract infections

Purpose: To evaluate the pharmacodynamic effect and cytotoxicity of S. cordatum pulp extract in the treatment of gastrointestinal tract infections. Methods: The air-dried fruit pulps were ground, extracted with 100 % methanol and screened for phytochemicals. Serial microdilution method was used to determine the antibacterial activity of the extract against Bacillus cereus (ATCC 10102), Staphylococcus aureus (ATCC 25925), Enterococcus hirae (ATCC 8043), Escherichia coli (ATCC 25922), Salmonella typhimurium (ATCC 700030), Klebsiella pneumonia (ATCC 4352), Pseudomonas aeruginosa (ATCC 7700), Vibrio fluvialis (AL 019) and Vibrio vulnificus (AL 042). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to assess the cytotoxicity of the extract. Antidiarrheal and antimotility activities were evaluated using castor oil-induced diarrhoea model in rats. Results: The extract revealed the presence of alkaloids, cardiac glycosides, flavonoids, saponins and terpenoids. Total phenolic content was 16.4 ± 1.8 µg/mg. The extract exhibited antibacterial activity with minimum inhibitory concentration (MIC) of as low as 3.13 mg/ml against B. cereus (ATCC 10102), S. aureus (ATCC 25925), E. hirae (ATCC 8043), P. aeruginosa (ATCC 7700) and K. pneumonia (ATCC 4352). Median inhibitory concentration (IC₅₀) of 92 µg/ml and therapeutic index of 0.1 - 0.3 were exerted by the extract. In vivo antidiarrheal activity was 49 % at extract dose of 400 mg/kg, which was much higher than that of the control (0 %). Conclusion: The fruit-pulp extract of Syzyhium cordatum has both antibacterial, antimotility and antidiarrheal activities, and may therefore be clinically safe for use at low concentrations as an antidiarrheal agent.