Berbaoui H, Cheriti A and Ould El Hadj-Khelil A
The study presents an interest in the antibacterial effect of some Asteraceae of southern Algeria, on nosocomial strains of the genus Staphylococcus precisely strains of two species Staphylococcus aureus and Staphylococcus epidermidis. Both species of Staphylococcus were omnipresent in nosocomial environment investigated according ato previous study. Plants tested were all shown an antimicrobial effect against the tested strains with maximum inhibition zone of 21 mm for Staphylococcus epidermidis for Cotula cinerea, Staphylococcus aureus shown maximum inhibition zones of 22 mm also for Cotula cinerea and bubonium graveolens and those for the reference strain, Staphylococcus aureus ATCC 25923, were 32 mm for Bubonium graveolens . Plants tested shown minimal inhibitory concentration ranging from 1 × 10-3 g to 5 × 10-4 g. Staphylococcus strains tested were totally resistant to β lactams with rate of 51.84% whereas their rate of resistance for cotula cinerea was only 07.21%.