Evaluation of Phytochemical and Antibacterial Potential of Vernonia amygdalina and Elaeis guineensis on Some Bacteria Associated with Diarrhea

Background: Bitter leaf and palm oil combination in treating diarrhoea is common in Africa. The aim of this study is to determine the synergistic and antimicrobial potential of Vernonia amygdalina and Elaeis guineensis on bacteria isolates from diarrheic stool.

Methodology: One hundred and fifty (150) diarrheic stool samples from the Diagnostic Laboratory in Rivers State University Teaching Hospital (RSUTH), Port Harcourt, were inoculated in Selenite F broth, MacConkey, Nutrient and Salmonella-Shigella agar plates using standard methods. Fresh and dry bitter leaf extracts were prepared by mashing, weighing and dissolving 100 grams(g) and 150 g concentrations of each in 100 milliliters(mls) of ethanol and sterile distilled water respectively. Undiluted mixture of bitter leaf and palm oil were prepared by mixing 2 mls of each in a sterile beaker. Zero-point one milliliter (0.1ml) of each undiluted extract, their mixture, ethanol and palm oil were separately dispensed into appropriately labeled wells using sterile pipette for sensitivity test on the isolated bacteria. The pH, temperatures and the phytochemical contents of the bitter extracts and palm oil were determined using pH meter, thermometer and spectrophotometric method.

Results: Escherichia coli, Staphylococcus aureus and Salmonella sp. were isolated. The pH and temperature of bitter leaf extract and palm oil were 7.2 and 26⁰C and 6.7 and 26⁰C respectively while the pH and temperature for bitter leaf and the palm oil mixture was 6.9 and 26⁰C. The bitter leaf and palm oil extracts, their combination, ethanol and distilled water used on the isolates as antibiotics did not show any sensitivity. The phytochemicals identified in the bitter leaf were saponins, alkaloids and tannins while carotene was detected in the palm oil.

Conclusion: It can be concluded that the bitter leaf extract, palm oil and their combination did not inhibit the growth of bacteria as a result of lack of bioactive components from the bitter leaf. The nature of the diluents used for the extraction may not have been the right one as it would have caused the low concentration, dilution and disfiguring of the molecules of the bioactive compounds that prevented the proper reaction between the bacteria and the extracts used.