Evaluation of In vitro Activity of Antimicrobial Potential and Phytochemical Screening of Methanol Extract of Curcuma longa Linn against Some Clinical Isolates

Abstract

Since ancient times, plants have been used as a source of medicinal compounds. This study was carried out to assess the antimicrobial potential of the methanol extract of Curcuma longa rhizome against some clinical isolates. A total of seven clinical isolates including Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Candida albicans, Aspergillus flavus, and Fusarium species were used. Different concentrations of the extracts were made. Agar well diffusion methods were used for bacterial and Candida albicans while agar dilution technique was used for the mold strains. Ciprofloxacin and Fluconazole were used as a standard positive control against the bacteria and fungi respectively. Dimethyl sulfoxide (DMSO) was used as a negative control. The result showed that methanol extract of Curcuma longa rhizome inhibited the growth of all tested organisms. The zone of inhibition of K. pneumoniae ranged from 9.33-13.33mm, S. aureus, 6.33-12.67mm, E. coli, 8- 11.67mm, P. aeruginosa, 7.67-10mm, and Candida albicans 8.33-13mm while the control drug Ciprofloxacin ranged from 25.33-41.33mm and fluconazole was 20mm. The percentage inhibition of diameter of growth of Fusarium spp ranged from 74.61-100% and that of A. flavus ranged from 32.44-100%. The positive control drug (Fluconazole) and 250mg/ml of the extract showed complete inhibition of the test organisms. Qualitative phytochemical studies of the extract of Curcuma longa in different solvents (N-hexane, water, methanol, and acetone) showed the presence of alkaloids, phenols, saponins, steroids, tannins, glycosides, and flavonoids. This result is indicative of its broad-spectrum antimicrobial potential and could be employed in the management and treatment of infections. This study corroborates the plant's historic use and lays the groundwork for potential therapeutic development.