ABSTRACT
Over the years, plants have been used as valuable sources of natural products for maintaining animal and human health. In Nigeria, a large percentage of the populace depends on herbal medication because the commercially available orthodox medicines are becoming increasingly expensive and out of reach. The aim of this study was to carry out the antibacterial and phytochemical properties of the leaf extracts of Bryphyllum pinnatum. Samples of Bryophyllum pinnatum leaves were collected from Department of Agriculture, Faculty of Agricultural Sciences, University of Benin, Benin City, Nigeria. The samples were taken to the laboratory for analysis. Freshly grown clinical isolates were collected from Medical Microbiology Laboratory, University of Benin Teaching Hospital (UBTH), Benin City, Nigeria. The phytochemical constituents of Bryophyllum pinnatum leaves were assayed using standard methods. The proximate analysis was carried out using the standard analytical methods. Antibacterial susceptibility tests of the extracts were carried out using agar well diffusion technique. Data obtained for the different parameters were subjected to statistical analysis. The results of the phytochemical analysis revealed the phenols (19.34 ±1.040 mg/100g), tannins (14.32 ±1.040 mg/100g), flavonoids (13.66 ±1.380 mg/100g), alkaloids (<0.01 ±0.00 mg/100g), saponins (6.54 ±1.330 mg/100g), steroids (<0.01 ± 0.00 mg/100g) and glycoside (2.58 ± 0.23 mg/100g) in aqueous extracts, while phenols (44.48 ±0.96 mg/100g), tannins (32.94 ±1.284 mg/100g), flavonoids (31.42 ± 2.835 mg/100g), alkaloids (3.17 ±0.59 mg/100g), saponins (2.26 ±0.390 mg/100g), steroids (0.25 ±0.00 mg/100g) and glycoside (0.73 ± 0.00 mg/100g) were present in the ethanolic extract. Aqueous and ethanolic leaf extract of Bryophyllum pinnatum inhibited the growth of the tested bacterial isolates with 100 mg/ml concentration having the highest zone of inhibition (24 ±1.0 mm; 18 ±1.0 mm) against Enterococcus faecalis respectively. The minimum inhibitory concentration of the aqueous extract against clinical isolates ranged from 25 mg/ml – 75 mg/ml while the minimum inhibitory concentration of the ethanolic extract against clinical isolates ranged from 50 mg/ml – 100 mg/ml while minimum bactericidal concentration ranged from 75 mg/ml – 100 mg/ml in both aqueous and ethanolic extracts. The proximate analysis revealed the presence of moisture (5.73 ± 0.52 %), protein (21.06 ± 0.29 %), ash (1.72 ± 0.00 %), fibre (3.54 ± 0.29 %), lipid (4.06 ± 0.40 %) and carbohydrate (59.89 ± 1.66 %). Gentamycin, xi pefloxacin and ciprofloxacin were the most sensitive antibiotic against Klebsiella oxytoca (32 ±2.8 mm), Pseudomonas aeruginosa (32 ±0.8 mm) and E. coli (31.4 ±0.9 mm) while chloramphenicol, sparfloxacin and streptomycin were the least sensitive antibiotics to K. oxytoca (19.2 ±3.3 mm), P. mirabilis (17.6± 0.7 mm) and E. faecalis (19.2 ±1.3 mm) respectively. The findings from the study indicated that Bryophyllum pinnatum is a possible important plant of medical and pharmacological value from which important drugs can be made. It confirms the efficacy of the plant extract as natural therapy, and this could employed in the treatment of infectious diseases caused by the test clinical isolates.
