ABSTRACT
Objective: To investigate the antibacterial activities of green vegetables (pennywort, mint, garlic, parsley and celery) against four common enteric bacteria [Salmonella enterica (ATCC 25957) (S. enterica), Shigella flexneri (ATCC 12022) (S. flexneri), Escherichia coli (ATCC 43889) (E. coli) and Enterobacter cloacae (ATCC 13047) (E. cloacae)] as an alternative medicine for controlling food borne diarrhea disease and the synergistic effect of green vegetables against those bacteria. Methods: Five common vegetables (pennywort, mint, garlic, parsley and celery) were purchased and extracted. The antimicrobial activities of these extracts were tested against four common enteric bacteria (S. enterica, S. flexneri, E. coli and E. cloacae). Ten different concentrations of the extracts (from 640 to 1.25 mg/mL) were prepared and used for the study. The minimal inhibitory concentration (MIC) was determined by the broth dilution method. The antimicrobial activities were assessed by using both well diffusion and disc diffusion methods. Results: Garlic extract showed excellent inhibitory effects on all enteric bacteria. Other plants (parsley, celery, mint and pennywort) were not effective against enteric bacteria. The MIC of garlic against S. flexneri and E. cloacae was 40 mg/mL. The MIC of S. enterica and E. coli were 20 and 10 mg/mL, respectively. The performance of the well diffusion method was better than that of the disc diffusion method with clear and sharp inhibition zones of tested bacteria against plant extracts. Conclusions: Garlic had excellent antimicrobial effects against enteric bacteria and was recommended to be given to patients with gastroenteritis. The other vegetables (pennywort, mint, parsley and celery) showed no inhibitory effects on enteric bacteria but still can be used for its richness in vitamins and fibers. The performance of the well diffusion method was better than that of the disc diffusion method in detecting the antibacterial effects of green vegetables.
ABSTRACT
Aims: Camellia sinensis ( green t ea) is known for its therapeutic properties (anti - inflammatory, anti - oxidative and anti - ageing). The aim of this study was to determine the in vitro inhibitory activity of gree n tea extract on some odorous skin commensal bacteria. Methodology and results: Tea leaves were collected from MARDI Agro Technology Park, Cameron Highlands. A standardised protocol was used to obtain green tea extract. Aqueous green tea extracts were tes ted for antibacterial activity by well diffusion method. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) assays were performed by broth microdilution assays using green tea extract concen trations from 16 to 0.0313 mg/ mL . Green tea extract showed antibacterial activity against skin microbiota. The high antimicrobial effect was achieved against Micrococcus luteus with MIC and MBC of 0.125 and 0.25 mg/μL respectively, followed by Staphylococcus epidermidis with MIC and MBC o f 0.25 and 0.25 mg/μL respectively, Bacillus subtilis with MIC and MBC of 0.5 and 0.5 mg/μL respectively and lastly, Corynebacterium xerosis with MIC and MBC of 0.5 and 1.0 mg/μL respectively. Conclusion, significance and impact of study: The results obta ined from the study confirm the in vitro anti - microbial activity of green tea extracts against skin microbiota. The antibacterial effects of green tea against skin bacteria with its anti - oxidant and anti - aging properties will help in keeping skin healthy, fresh and reducing unpleasant odo rs .