Identification of Streptococcus sanguinis genes producing biofilm from gingivitis.

Streptococcus sanguinis is a teeth commensal frontier colonizer and among the most common species in the oral biofilm. Dental plaque, caries, and gingivitis/periodontitis are caused by dysbiosis of oral flora. A biofilm assay was developed to investigate biofilm formation in S. sanguinis using the microtiter plate, tube, and Congo red agar methods in order to identify causing bacteria and determine responsible genes. Three genes, including pur B, thr B, and pyre E, were suspected of playing a role in forming in vivo biofilms in S. sanguinis. The present study shows these genes to be responsible for increased biofilm formation in gingivitis patients.

The effect of black and green tea extracts on some bacteria-infected burns skin in rats.

Herbal teas are the most common natural alternatives for the treatment of infectious diseases due to increasing antibiotic resistance, and are increasingly gaining more popularity and are known for their activity of antibacterial to many pathogenic micro-organisms. This research was necessitated by the need to counter the rapid emergence of drug-resistant human pathogens, which is becoming a regular phenomenon in the world making life-threatening illnesses easily curable infections. The study was done to determine the antimicrobial activities by agar diffusion inhibition assay of black and green tea Extract (cold and hot) against Pseudomonas aeruginosa and Staphylococcus aureus antibiotic resistance after injuring the skin of rats for burning, also to screen the effect of both types of tea on rat skin healing. Minimum inhibitory concentration was performed by broth micro-dilution assays, and Antibiotic Sensitivity was done for both types of bacteria. Our findings are in accordance that hot watery green and black tea extracts are more effective against both bacterial types than cold once based on an assessment of inhibition zones, green tea extract could be used for wound healing and burned skin of rats when treated with green and black tea showed reductions in the number of inflammatory cells and also arranged collagen bands. We concluded that green tea has a greater activity which is indicated by a higher anti-inflammatory effect compared to black tea.