PHYTOCHEMICAL SCREENING, IN-VITRO EVALUATION OF ANTIOXIDANT AND ANTIBACTERIAL EFFICACY OF METHANOLIC LEAF EXTRACT OF CLINOPODIUM NEPETA (L.) KUNTZEAbstract
The objective of the present study is to evaluate the phytochemical constituents, antioxidant and antibacterial activities of methanolic leaf extract of Clinopodium nepeta (L.) Kuntze. Total phenolic content of leaf extracts was assessed using Folin-Ciocalteu and AlCl3 reagent. Antioxidant assays were evaluated using DPPH, ABTS radical scavenging, and ferric, reducing antioxidant power (FRAP) methods. The leaf extract was screened against four pathogenic bacteria, two gram-positive (Escherichia coli, Bacillus cereus) and two-gram negative (Pseudomonas aeruginosa, Klebsiellea pneumonia) using disc diffusion method. The results showed the total phenolic content (378.52mg gallic acid equivalent (GAE)/g) and flavonoid content (189.4 mg quercetin equivalents (QE)/g) of methanolic leaf extracts. DPPH and ABTS radical scavenging activity with an IC50 value of 0.49mg/ml and 1.68mg/ml, respectively. It also exhibited good absorbance in the FRAP assay. The in-vitro antibacterial assay showed an excellent zone of inhibition against Pseudomonas aeruginosa (19.01±0.3mm), Bacillus cereus (24.66±0.3mm), Klebsiellea pneumoniae (16.74±0.3mm), and Escherichia coli (17.56±0.31). Clinopodium nepeta (L.) Kuntze showed maximum antioxidant property and maximum inhibition against the test organisms. The high phytochemical constituents coupled with antioxidant and antibacterial activities of the leaves of Clinopodium nepeta (L.) Kuntze is indicative of its ability to treat various diseases and therefore supports its use in ethnomedicine.
M. D. Ghosh *, D. B. Golageri, W. K. S. Sandaruwan, J. Vishnu and S. Rachel
Department of Chemistry, Indian Academy Degree College Autonomous, Bangalore, Karnataka, India.
24 May 2020
21 July 2020
24 November 2020
01 December 2020