ANTIOXIDANT AND ANTIMICROBIAL ASSAY OF THE CRUDE METHANOL EXTRACT OF THE LEAF OF LAWSONISA INERMIS. LINN

ABSTRACT The use of medicinal plants as natural substitute is the main focus of research in order to overwhelm the drug resistance of infectious agents with high level of potency and effectiveness and no or minimal tisxicity. Lawsonia inermis Linn is a member of the lyrthocede family and is also known as "Henna" in India. It is known to posses both Traditional, medicinal and ethnobotanical uses. Methanol was used as solvent for extraction of Lawsonia inermis leaf constituents. In this research work, the methanol extract of Lawsonia inermis was evaluated for both antioxidant and antibacterial properties. The antibacterial property of the plant's leaf extract was evaluated using dise-diffusion assay of antimicrobial activity. The extract was investigated against seven bacterial isolates; Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, klebsiella pneumonia, Bacillus subtilis, Staphylococcus citrus. The presence of inhibition zone diameter indicated it has possesses antimicrobial activity. In the determination of the plant's extract antioxidant activity, DPPH (2,2-diphenyl-1-pierylhydrazyi) method of antioxidant assay was used. A UV/Vis spectrophotometer was used to measure the absorbance at 517nm. The free radical scavenging assay obtained ranged between 6.93-62.63 for the plant extract and 12.46-90.08 for the Ascorbic acid. In determining the antimicrobial activity of the plant extract, the inhibition zone diameter of the various microorganism which ranged from 7.04-11.06 for the 5mg disc, 8.90-12.88 for the 10mg disc and 8.25-15.08 for the 20 mg dise was observed. The result obtained was plotted on a bar chart. In summary, the crude methanol extract of Lawsonia inermis possessed both Antimicrobial and antioxidant property.