Phytochemical Analysis and Antibacterial Activity of selected Kenyan Wild Orchids

Abstract The current study evaluated antibacterial activity of dichloromethane and methanol (DCM-MeOH) extracts of four Kenyan orchid species against three selected bacterial strains. Extracts of E1 (Ansellia africana), E2 (Trydactylescottelli), E3 (Polystachyabella) and E4 (Liparis bowkeri) were screened for antibacterial activity againstStaphylococcus aureus, Bacillus subtilis and Pseudomonas aeruginosausing agar disc diffusion. Ampicillin was included as a positive control.Qualitative analysis revealed the presence of flavonoids, saponins, alkaloids, tannins, terpenoids, steroids and glycosides. Trydactyle scottelli and Polystachyabella extracts revealed stronger presence of tannins and steroids respectively compared to the others. All extracts showed varying levels of antibacterial activity against the test bacteria. However, extracts of Polystachyabella and Liparis bowkeri against Bacillus subtilis and Ansellia africana against Pseudomonas aeruginosa exhibited higher activities similar to that of Ampicillin. The study further showedthat the DCM-MeOH extracts of the four orchids contain potential bioactive compounds that should be further analysed for conventional and traditional management of bacterial infections.