Abstract

IN VITRO ANTIOXIDANT AND ANTISALMONELLAL ACTIVITIES OF HYDROETHANOLIC AND AQUEOUS STEM BARK EXTRACTS OF KHAYA GRANDIFOLIOLA (MELIACEAE)

Yamako Konack E., Kamsu T. G., Djenguemtar J., Sokoudjou J. B., Kodjio N., Feudjio H. B. L. and *Gatsing D.

ABSTRACT

Salmonella infections remain a significant problem in the veterinary and human health sector. In addition, the inappropriate use of antibiotics as growth factor or against infectious diseases has led to resistance issues, especially in poultry farm. The aim of this study was to evaluate the in vitro antisalmonellal and antioxidant properties of Khaya grandifoliola in order to develop new control strategies against salmonellosis. The antisalmonellal properties of Khaya grandifoliola were evaluated (against two isolates and one strain of Salmonella) by serial dilution method while the antioxidant activities and phytochemical screening were performed using standard methods. The result showed that the 95% ethanol and hydroethanolic 70% extracts of Khaya grandifoliola were the most active against Salmonella Typhimurium and Salmonella Typhi, having the same MIC (128 µg/ml). For the DPPH• radical scavenging activity, all the hydroethanolic extracts and decoction showed IC50 ˂ 12.5 µg/ml while the IC50 of infusion and the maceration were 39.57 µg/ml and 15.16 µg/ml, respectively. In the FRAP assay, the reducing power of the 70% ethanol extract is the highest of all the extracts (1.46) at a concentration of 50 μg/ml followed by 50% and 30% ethanolic extracts. At 200 µg/ml, the 95% ethanol extracts, 70% and the infusion showed the strongest reducing power of iron (1.41). At the highest concentration (200 µg/ml), the anti-radical power of hydroxyl is highest for the 95% extracts (11.00), followed by maceration and 30% hydroethanolic extract. The overall results of this study showed that extracts of Khaya grandifoliola especially the 95% ethanol extract can be successfully used as alternative treatment against salmonellosis.

Keywords: Salmonella, Khaya grandifoliola, antisalmonellal potential, antioxidant activity.