In vitro Antioxidant Activities and Effect of Hydroethanolic and Aqueous Extracts of Terminalia avicennioides (Combretaceae) on Salmonella

Abstract

Today, Typhoid fever remains a public health problem in developing countries due to the poor quality of lifestyle associated with abusive and inappropriate use of antibiotics. Aims: Considering the ethnopharmacological relevance of Terminalia avicennioides                              (T. avicennioides) (Combretaceae), this study was designed to investigate the in vitro antisalmonella and antioxidant activities of various extracts of this plant. Methodology: The microdilution method was used to determine the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of T. avicennioides extract. These extracts were also subjected to in vitro antioxidant tests such as diphényl-2-picrylhydrazyle (DPPH) radical scavenging test, ferric reducing-antioxidant power (FRAP), hydroxyl radical (OH) nitric oxide (NO) and Hydrogen Peroxide Scavenging Capacity. Results: In vitro antisalmonella activity reveals that T. avicennioides stem bark extracts presented MIC values ranging from 64 to 512 μg / mL on tested microorganisms. This extract exhibited a good ability to trap DPPH with an IC50 of 8.30 μg / mL. The iron reducing power obtained with this extract had ODs ranging from 0.96 to 1.63. Phytochemical screening showed the presence of alkaloids, flavonoids, saponins, phenols anthocyanin and anthraquinone in all the extracts. Conclusion: The results suggest that stem extract of T. avicennioides contains antisalmonella and antioxidant substances, which could be used for the treatment of typhoid fever and another salmonellosis.