In vitro antibacterial, non-cytotoxic and antioxidant activities of Boscia Senegalensis and Tapinanthus dodoneifolius, plants used by pastoralists in Cameroon

Abstract

In the Far North Region of Cameroon, pastoralists use the leaves of Boscia senegalensis and the stem of Tapinanthus dodoneifolius to treat common animal diseases. This study aimed to evaluate the in vitro antibacterial, non-cytotoxic and antioxidant potentials of these plants. To achieve this, four extracts (water, methanol, chloroform and hexane) of both plants obtained by successive fractionation were used. Antibacterial activities of the different extracts were evaluated against three bacterial reference strains including Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli and Salmonella typhi) using agar disc diffusion and broth dilution methods. Human colon cancer cells were used to screen their toxicity. 2,2-Ddiphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferrous ion chelating assays have been used to investigate the antioxidant activities of the best extract of each plant after antibacterial assay. A sensitive inhibitory effect was observed against S. aureus with hexane extract of B. senegalensis and methanolic extract of T. dodoneifolius. In addition, the results showed that both plant extracts are not toxic. The hexane and methanolic extracts of B. senegalensis and T. dodoneifolius, respectively, showed higher antioxidant activities, but the hexane extract demonstrate a strong hydrogen donating ability or the electron transfer reaction in comparison with vitamin C used as standard. This finding may support the traditional use of both plants for managing animal diseases in the Far North of Cameroon.