Antimicrobial, Phytochemical and Antioxidant Screening of Acalypha fimbriata Leaf Extract for Alternative Antimicrobial Therapy

Abstract

In folklore, Acalypha fimbriata have been associated with ‘cure all’ properties, but without sufficient empirical ethno-pharmacological scientific backups. This research work is therefore necessitated to determine the antimicrobial, phytochemicals and antioxidant activity of Acalypha fimbriata. The leaf of Acalypha fimbriata were Soxhlet extracted, reconstituted, and screened for phytochemical constituent of antimicrobial importance. Conventional biochemical characterization was carried out on the isolates of Staphylococcus aureus, Escherichia coli Pseudomonas aeruginosa and Klebsiella pneumoniae obtained for the research work and the antimicrobial activity of the plant sample was determined using the agar well diffusion technique. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) of the extract were determined by broth dilution method on the isolates. The antioxidant activity of the extract was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and Graphpad prism were used to interprets the data. Alkaloids, flavonoid, anthraquinones, tannins and saponins was found in the leaf extract. Staphylococcus aureus exhibited highest zone of growth inhibition (28mm) at 100mg/ml while Pseudomonas aeruginosa had the lowest (14mm) at 100mg/ml from the antimicrobial assay. In the determination of the minimum inhibitory concentration and minimum bactericidal concentration, Staphylococcus aureus exhibited MIC and MBC at 0.625µg/ml and 12.5 µg/ml, while Pseudomonas aeruginosa elicited MIC and MBC at 10 µg/ml and >10 µg/ml of MIC and MBC respectively. Themethanol extract of the plant acted as hydrogen/electrons donor or scavenger of radicals with fifty percent inhibitory concentration (IC50) of 59.83 µg/ml while that of Ascorbic acid (standard) was found to be 92.70 µg/ml using. The varied MIC’s and MBC’s obtained coupled with the values recorded for the antioxidant radicals validate the antimicrobial and antioxidant potential of Acalypha fimbriata that can be explored for therapeutic option, if further purified and optimally processed.