Synergistic Effect of the Extracts of Vernonia amygdalina and Solenostemon monostachyus on Gram-negative Bacteria.

Abstract

Herbal medicines are getting more importance in the treatment of infections ailments because most of the synthetic drugs have side effects. A large proportion of the developing countries populations depend on herbal remedy for their physical and psychological health needs depend. Hence, the anti-bacterial activity of the mixture of the extracts of Solenostemon monostachyus and Vernonia amygdalina, common medicinal plants use in Africa, Asia and Europe on some Gram-negative bacteria was investigated. The plants that were cultivated in a well-drained soil and the bacteria, Salmonella typhii, Escherichi coli and Enterobacter aerogenes freshly isolated from clinical samples were used for this study. The plant leaves were grounded separately into a powder and analyzed quantitatively for phytochemical composition and extracted using acetone. Similarly, equal volume of the two plants was homogenized. The sensitivity of the bacteria isolates was performed using disk diffusion method and the antimicrobial activity was determined by measuring the diameter zones of inhibition and for the sensitive measurement (inhibitory zones >20) and resistant measurement (inhibitory zones <17). Analysis of the plants revealed their phytochemical composition. The plant's extracts had high diameter zones of inhibition at the higher concentrations and the concoction treatment was more sensitive. In V. amygdalina, the zone of inhibition varied significantly between S. typhi and E. aerogenes (p<0.05, F = 7.2) and between E. coli and E. aerogenes (p<0.05, F = 6.7), while in S. monostachyus, it varid significantly between S. typhi and E. coli (p<0.05, F = 9.2) and between E. coli and E. aerogenes (p<0.05, F = 5.8). These plants were readily available at no cost therefore, they could be exploited to provide novel compounds that may be used as starting materials for the production of drug that can obliterate resistance bacteria.