Résumé:
The assigned objective to this experimental research work is to determine the antimicrobial effect of phenolic compounds "Mentha piperita L" on the lactic acid germ "Lactobacillus bulgaricus" specific to yogurt. Moreover, the phenolic components of the studied plant were collected and extracted (in the Wilaya of Ouargla) by maceration in an aqueous solution. Furthermore, the measurements of the antibacterial activity of the aqueous extract that is rich of phenolic compounds were carried out in vitro triplicate tests on the bacterial strain "Lactobacillus bulgaricus" that are concerned with the growth tests, the test of the diffusion discs on agar, the concentration minimum inhibitory and minimum bactericidal concentration.
The aqueous extract of "Mentha piperita L" that is rich in phenolic compounds (45.41 mgEAG / ml) and poor in flavonoids (0.43 mgEQ / ml) results it a remarkable inhibitory activity on the growth of the germ "Lactobacillus bulgaricus". It seems to exert an inhibitory effect of the bactericidal type on the growth of this lactic acid germ. MIC and CMB in Lactobacillus bulgaricus were obtained at concentrations of 40% and 60%, of aqueous extract of peppermint.
