Extraction study and the antibacterial activity of phenol and flavonoid contents in Mentha pulegium L. from Algeria

The present study describes the total phenolic and flavonoids content,and in vitro antibacterial activity of petroleum ether,ethyl acetate and n-butanolic extracts from mentha pulegium l. growing in tarik ibn ziad within the region of ain-defla located in northern algeria. the harvesting of the plant is made for three months: february,march and april 2013. we chose four bacterial strains common in human pathology,belonging to gram positive and gram negative classes. bacterial strains used were: pseudomonas aeruginosa (gram negative),escherichia coli (gram negative),klebsiella pneumoniae (gram negative) and staphylococcus aureus (gram positive). these bacterial species are responsible for skin infections (staphylococcus aureus),urinary and digestive tract infections (escherichia coli),and nosocomial infections (klebsiella pneumoniae and pseudomonas aeruginosa). antimicrobial was performed with the bauer-kirby method by the well diffusion technique using petri plates made by muller hinton agar containing the culture. we initially made the extractions with ethanol and after we used petroleum ether,etoac and n-buoh. tests by the shibata reaction and chromatography (tlc) showed the presence of flavonoids in all samples. the quantitative determination of total polyphenols by folin-ciocalteu presented the richness of ethyl acetate extract polyphenol (115.81,277.38,and 61.36) μg gae/g (microgram of gallic acid equivalent / gram) for crops of february,march and april respectively. expression of results of antibacterial activity showed that the petroleum ether extract (28%) and the n-butanol extract (30.67%) are more active in klebsciella pneumoniae; by against the ethyl acetate extract is more active on e .coli (32%).