Studies on the Antibacterial Activity and Chemical Composition of Methanol Extract of Cochlospermum tinctorium Root

Abstract

The aim of study was to evaluate the antibacterial activity of Cochlospermum tinctorium against ten (10) strains of antibiotic resistant food-borne pathogens Staphylococcus aureus and Listeria monocytogene. Ten (10) strains of antibiotic resistant food-borne pathogens Staphylococcus aureus and Listeria monocytogene procured from Microbiology Research Laboratory Usman Danfodiyo University Sokoto. The roots of Cochlospermum tinctorium were collected from the rock side in Dambu Gomo, Zuru Local Government Area of Kebbi State, Nigeria. The roots were washed, air-dried and milled to powder using mortal and pestle and sieved to obtained fine powder. Maceration was used for extraction using methanol as solvent. The antibacterial activity of the plant was determined on Mueller Hinton agar using agar well diffusion method. Minimum concentration (MIC) and minimum inhibitory concentration (MBC) of plant extract was also determined. Thin layer chromatography and column chromatography was employed for separation and fraction of different compounds in the plant extract. The fractions were screened for antibacterial activity and active fractions having high antibacterial activity were subjected Gas Chromatography Mass Spectoscopy (GC-MS) analysis. The result of methanol extraction yield 5.17% extracts. The methanol extract of Cochlospermum tinctorium was effective in inhibiting the isolates at high concentration of 10 mg/mL. The results thin layer chromatography revealed four spots with Rf values 0.02, 0.37, 0.44 and 0.80 respectively. The GC-MS analysis of the active methanol extract of Cochlospermum tinctorium root powder revealed the existence of major peaks 1-(+)-Ascorbic acid 2,6-dihexadecanoate (R.T: 13.666), Diethyl phthalate (R.T: 10.440), Undecyl acetate (R.T: 10.007), 3-tetradecanone (R.T: 9.793), 3-hexadecanone (R.T: 12.427). It therefore concluded that the root of Cochlospermum tinctorium has immense potential to be used in the area of pharmacology as it possess antimicrobial activity against the antibiotic resistant food-borne pathogens, thus could be exploited as alternative antimicrobial drugs.