study of antibiotic resistance and biofilm formation of staphylococci isolated from dental department liquid effluents

Staphylococcus sp. are pathogenic bacteria commonly found in clinical environments, including dental clinics. their pathogenic potential derives from their ability to express various virulence factors. our study was conducted to investigate the prevalence of antibiotic resistance and biofilm formation by strains of staphylococcus isolated from the liquid effluent of two (02) dental practices in sidi bel abbés, algeria. seven strains (07) were purified from three (03) oral rinse samples collected. three (03/07) were positive on chapman agar, with positive catalase, confirming their belonging to the staphylococcus genus. biochemical gallery identification revealed three different biotypes: 4104100: staphylococcus capitis, 6310111: staphylococcus warneri, 6104100: staphylococcus capitis, using the api staph system. all strains tested positive for free coagulase in tubes and bound coagulase, which the staphytect plus latex agglutination test confirmed. in addition, our strains showed positive dnase activity. the isolated strains were multi-resistant to antibiotics, with antibiotic susceptibility tests revealing total resistance (100%) to the following antibiotics: penicillin, oxacillin, cephalotin and nalidixic acid. the 03 strains also showed morphological characteristics of biofilm formation when grown on congo red agar, in which biofilm-producing colonies appeared black. the study highlights the need for further research to explore the underlying resistance mechanisms and identify innovative strategies to prevent and eradicate biofilms to curb the spread of resistant bacterial strains.