Antimicrobial Screening and Phytochemical Analysis of Elaeis guineensis (Ewe Igi Ope) against Salmonella Strains

Aim: The study aimed at determining the in vitro anti-salmonella effect of Elaeis guineensis on Salmonella species isolated from clinically suspected typhoid fever patients in FUTA, Nigeria.

Study Design: The study evaluated the prospective use of Elaeis guineensis as an alternative to conventional drugs in the treatment of salmonellosis and gastroenteritis.

Place and Duration of Study: Federal University of Technology, Akure (FUTA) Health Centre was used for the study which Investigation was done during June to September, 2015.

Methodology: Two hundred (200) blood samples were collected from clinically suspected typhoid fever patients attending FUTA Health Centre in Akure, Ondo State, Nigeria. Salmonella Typhi and Salmonella Typhimurium were isolated from the blood samples using selective media. The identities of the isolates were verified using conventional microbiological techniques. Elaeis guineensis leaves were collected from Federal University of Technology Akure (FUTA) Teaching and Research Farm, and the plant’s identity was authenticated using standard manuals at Crop Science and Pest Department, FUTA. The antibacterial effect of methanolic, acetone and hexane extracts of the plant leaves on Salmonella Typhi and Salmonella Typhimurium were evaluated. Quantitative and qualitative phytochemical screening were performed on the leaf extracts. Antibiotics susceptibility profile of the isolates was also assessed using commercially available antibiotics.

Results: The highest zone of inhibition (21.67±1.20 mm) was observed with the methanolic extract at concentration of 100 mg/mL for Salmonella Typhimurium. No zone of inhibition was observed for hexane at the concentration of 6.25 and 12.5 (mg/mL). Highest zone of inhibition (17.00±0.58 mm) was observed with the methanolic extract at concentration of 100 mg/ml for Salmonella Typhi and the least (0.33±0.33 mm) was observed with the hexane extract at a concentration of 25 mg/mL. Phytochemical analysis of the extracts revealed the presence of many secondary metabolites including alkaloids, flavonoids, tannins and saponins. Flavonoids was highest (118.03±0.29) in methanol extract and least (8.00±0.00) in hexane extract. Same trend was observed for other phytochemicals present. As for the conventional antibiotics, Salmonella Typhi had the highest zone of inhibition (23.00 mm) with ciprofloxacin and the least (1.33 mm) with augmentin, Salmonella Typhimurium recorded the highest zone of inhibition (23 mm) with ciprofloxacin and pefloxacin, while the lowest (4 mm) was recorded with tetracycline.

Conclusion: These findings showed that Elaeis guineensis is a potential source of reliable phytotherapy in combating salmonellosis and gastroenteritis.