This study was aimed at evaluating the extract of Jatropha tanjorensis leaves for bioactive components, proximate composition and antimicrobial activity. The collection of the plant leaves, processing of the leaves and extracts were all done using standard methodologies. Qualitative screening and gas chromatography (GC-MS) were used to screen for phytochemicals. Proximate composition, vitamins, minerals and anti-nutrients were all carried out using standard techniques. Standard microbiological techniques were used to isolate, characterize and identify Escherichia coli isolates from dumpsite soil samples. The standard disc method was used to assay the antibiotics sensitivity of the test antibiotics and that of the extracts. The proximate nutrients and their respective amounts in g/100g per dry matter were moisture (80.23±1.53), protein (5.01±0.17), ash (2.91±0.31), crude fiber (3.21±0.17) fat (1.94±0.11) and carbohydrate (86.93±1.47). Mineral analysis revealed the presence of sodium, potassium, calcium, magnesium, zinc, copper, and iron. Furthermore, vitamin analysis showed the presence of vitamins A, B, C and E. Anti-nutrient analysis revealed the presence of permissible levels of hydrocyanic acid, soluble oxalate, total oxalate, and phytate. Phytochemical analysis via GC-MS revealed a total of 16 compounds belonging to five different categories of phytochemical namely: alkanes and associated hydrocarbons, organic acid and fatty acid, flavonoids, alkaloids and amines. Organic and fatty acids had the highest concentration of 80.52% followed by flavonoids with a concentration of 18.44%. Alkaloids, amines and alkanes and associated hydrocarbons had concentrations of 0.18, 0.692 and 0.113, respectively. The test antibiotics showed zones that ranged from 12.00 to 23.00mm. The highest and least zones of inhibition were 28.00 and 10.00 mm for aqueous extract while it was 17.30 and 10.00 mm for ethanolic extract, respectively. Jatropha tanjorensis could be rich source of nutrients, vitamins, essential minerals as well as phytochemicals with effective antimicrobial potential against Escherichia coli.

Keywords : Nutrition, Phytochemicals, Jatropha tanjorensis Leaf Extract, Escherichia coli, Antimicrobial Susceptibility.