Phytochemical screening and antibacterial activity of the aqueous extract of the leaves of Alchornea cordifolia (Euphorbiaceae) on the in -vitro growth of tetracycline-resistant strains of avian Escherichia coli

Abstract

Tetracycline is one of the most widely used antibiotics in poultry farming for the control of bacterial pathologies such as Escherichia coli, responsible for colibacillosis, causing significant economic losses in poultry farming. Unfortunately, high rates of resistance of these bacteria to tetracycline are increasingly observed. Thus, the search for new effective molecules is proving to be an alternative. It is in this context that this study is carried out with the objective of proposing a medicinal plant as an alternative to the fight against bacteria resistant to Tetracycline. Phytochemical analysis revealed the presence of phenols, flavonoids, catechic tannins, saponosides, sterols, polyterpenes, alkaloids and quinonics. The bacterial strains were sensitive to the aqueous extract with inhibition diameters ranging from 13.3± 0.3 and 18.3 ± 0.6 mm at 200 mg/ml. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract ranged from 3.12 to 50 mg/ml and 6.25 to 100 mg/ml respectively with MBC/MIC ratios ≤ 2 for all bacterial strains. Thus, the extract has bactericidal potential on all the strains after 24 hours and 48 hours of incubation. The antibacterial potential of this extract highlighted in this study could make this plant a candidate for further investigations that may lead to the discovery of new antibacterial molecules.