In Vitro Anti-Bacterial Activities of Aqueous, Ethanol and Chloroform Crude Extracts of Olinia Rochetiana, Vernonia Myriantha and Diclipteria Laxata
| dc.contributor.advisor | Mamo Hassen (PhD) | |
| dc.contributor.author | Erdedo Ayana | |
| dc.date.accessioned | 2019-08-28T13:33:22Z | |
| dc.date.accessioned | 2023-11-08T16:39:17Z | |
| dc.date.available | 2019-08-28T13:33:22Z | |
| dc.date.available | 2023-11-08T16:39:17Z | |
| dc.date.issued | 2018-01-04 | |
| dc.description.abstract | With the advent of antibiotics, bacterial diseases which claimed enormous lives in the past have been put under control. However, the emergence and rapid spread of antibiotic-resistant bacterial strains is reversing this success and searching for newer antibacterial agents is currently a top priority. This study was, thus, aimed at assessing the anti-microbial activities of three traditional medicinal plants: Vernonia myriantha, Diclipteria laxata and Olinia rochetiana. The leaves of the three plants and stem-bark of the last one was collected from their natural habitat in Hadiyya, southwest Ethiopia, washed and air-dried in shade and ground into a powder. Each plant powder was soaked in water, ethanol and chloroform in separate Erlenmeyer flasks in a 1:10 solute-solvent ratio and placed on a water bath shaker for 72 hours. The extracts were concentrated in a rotary evaporator and dried on an oven at 35 and the aqueous extract was freeze-dried using a lyophilizer. The crude extracts were tested for their in vitro antibacterial activities, in vivo acute toxicity and phytochemical content. The extracts were tested against selected 3 clinical and 4 standard test bacterial strains by using agar well-diffusion method and the minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC). The ethanol leaves and stem-bark extracts of O. rochetiana inhibited the growth of all bacterial strains at a concentration of 250mg/mL. The inhibition zones, ranged from 20.33±0.57mm for clinical Pseudomonas aeruginosa to 25.66±0.57mm for standard Salmonella typhi strains. The values for these same extracts were 20.66±2.51mm and 24.33±1.15mm for standard P. aeruginosa and Staphylococcus aureus strains respectively. The chloroform extract was similarly effective against all of the strains with inhibition zones between 19.00±1.73mm against P. aeruginosa and 22.66±2.51mm for S. aureus. Comparatively, the ethanol extract of O. rochetiana had the lowest MIC (1.95mg/mL) and MBC of 31.25mg/mL against S. aureus. The highest MIC (7.81mg/mL) and MBC (62.50mg/mL) were noted against P. aeruginosa. On the other hand, chloroform extract of O. rochetiana leaf showed the lowest MIC (3.9mg/mL) and MBC (62.5mg/mL) against S. aureus and the highest MIC (15mg/mL) and MBC (125mg/mL) were recorded against P. aeruginosa. The ethanol extract of V. myriantha showed growth inhibition only on S. aureus (21.00±1.7mm). While none of D. laxata extracts demonstrated any antibacterial activity, only the aqueous extract failed concerning O. rochetiana and V. myriantha. The ethanol and chloroform extracts of O. rochetiana and ethanol extract of V. myriantha were not toxic to Swiss albino mice up to dose 2000mg/kg. Both plants tested for terpenoids and glycosides showed positive result, but none for resin. Tannins, phenols, steroids and saponins were detected only in O. rochetiana, and flavonoid and alkaloid only in V. myriantha. It is worth considering these two plants for future antibacterial discovery studies in light of their potential and safety. | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/123456789/18890 | |
| dc.language.iso | en | en_US |
| dc.publisher | Addis Ababa University | en_US |
| dc.subject | Antibacterial Activity | en_US |
| dc.subject | Minimum Inhibitory Concentration | en_US |
| dc.subject | Minimum Bactericidal Concentration | en_US |
| dc.subject | Phytochemicals | en_US |
| dc.subject | Crude Extract | en_US |
| dc.subject | Pathogenic Bacteria | en_US |
| dc.title | In Vitro Anti-Bacterial Activities of Aqueous, Ethanol and Chloroform Crude Extracts of Olinia Rochetiana, Vernonia Myriantha and Diclipteria Laxata | en_US |
| dc.type | Thesis | en_US |