Antimicrobial activity of aqueous and methanol extract of naturally growing and cultivated Aloe turkanensis

Abstract

The aim of the study was to determine the antibacterial properties of aqueous and methanol extracts of naturally occurring and cultivated Aloe turkanensis. The plant is widely used as a traditional herb by communities in Turkana County, Kenya. However its efficacy has not been established. Aqueous and methanol extract of a naturally occurring whole Aloe turkanensis and cultivated one was obtained. The extracts were tested for in-vitro activity against 4 standard bacterial cultures and a fungal clinical isolate. Benzyl penicillin, Gentamycin and Amphotericin B were used as positive controls. Efficacy data analysis showed that methanol extracts of naturally growing plant inhibited the growth of B. cereus (100 mg/ml), S. aureus (100 mg/ml), and P. aeroginosa (200 mg/ml) with mean diameters of inhibition zones for S. aureus and B. cereus being 18.5±0.7 mm and 16.5±0.7 mm, respectively. Aqueous extract of the plant inhibited the growth of B. cereus and S. aureus at a Minimum Inhibitory Concentration of 200 mg/ml and 50 mg/ml respectively with mean diameter of inhibition zones for S. aureus and B. cereus being 19.75±1.0 mm and 11.5±0.0 mm respectively. Methanol extracts of cultivated A. turkanensis inhibited the growth B. cereus (100 mg/ml), S. aureus (50 mg/ml), E. coli (400 mg/ml) and P. aeroginosa (200 mg/ml) with mean diameters of inhibition zones for S. aureus and B. cereus being 18.5±0.7 mm and 11.5±0.0 mm respectively. There was a significant difference in antibacterial activity between the two plant ecotypes (p<0.05).