Phytochemical analysis and in vitro antibacterial activity of curcuma longa extracts against escherichia coli and cholera vibrio

Abstract

Antibacterial resistance poses a threat to global public health. To respond to the challenges imposed on the scientific community by the WHO, several studies are carried out to test the antimicrobial activities of medicinal plants, with the aim of designing new molecules with more effective pharmacological potential or of developing new antibiotics. In this context, this experimental laboratory research, quantitative with non-probabilistic convenience sampling, aims to analyze the chemical composition and antibacterial activity of extracts of the rhizome of Curcuma longa (Turmeric) against E. coli and Choleric vibrio. The rhizome extracts were obtained through the maceration method with 90% ethanol and the crushing technique to obtain the extract. Secondary metabolites were identified using specific reagents for each class. Analysis of antibacterial activity was performed using the disk diffusion method described by Kirby-Bauer. The impregnation, in triplicate, of the 0.4cm diameter filter paper discs was carried out at concentrations of 20mg/ml, 30mg/ml, 40mg/ml and 90mg/ml to obtain the ethanolic extract and the natural extract of the rhizomes. In the phytochemical analysis, Saponins, alkaloids and flavonoids were identified. The diameters of the inhibition halos for ethanolic extracts ranged from 6mm to 12mm and the unnatural form from 6mm to 13mm. The Mann-Whitney U test had P=0.050 indicating that there is no statistically significant difference between the inhibition zones and the concentrations tested for E. coli and V. choleric. It is concluded that the secondary metabolites found are precursors of antibacterial activity.

Key words: Antibacterial activity, phytochemical analysis, Curcuma longa L.