Characterization of capsule expression of both MSSA/MRSA strains isolated from various body sites of colonization and infections in Amman and Gaza

Abstract Background: Staphylococcus aureus is a major cause of nosocomial and community-acquired infections. Despite the predominance of two capsular polysaccharides, types 5 and 8, on the surface of clinical isolates, molecular and epidemiological variations have been reported among various geographical areas in addition to various clinical outcomes of S. aureus increasing the challenge for preventive and control measurements against staphylococcal infections and diseases. Materials and Methods: A total of 315 S. aureus isolates of various clinical conditions comprised both hospital and community-acquired infections between 2009 and 2011 in Amman and Gaza were studied. All S. aureus clinical isolates included in the present study have been investigated by PCR method to determine the distribution and diversity of capsule polysaccharide expression. Results: Collectively, most of the clinical isolates (90%) expressed either capsular polysaccharide CP5 (37%) or CP8 (53%), whereas 10% were nontypeable by PCR. Interestingly, significant predominance of CP8 genotype was reported in clinical strains of S. aureus isolated from infections in comparison to those which are commonly colonising various normal body sites. Conclusion:  Correlation between capsule genotypes and pathogenic behaviour of S. aureus could be established. Further studies on the molecular levels are required to determine the role and mechanisms of capsular expression in the variability of pathogenic potential of S. aureus

In Vitro anti- Helicobacter pylori and urease inhibitory effects of polyphenolic extracts of local herbs from Algeria

Gastritis and peptic ulcers are considered as major health problems worldwide with more than 80% of chronic active gastritis are due to the pathogenic bacterium H. pylori. Due to the emergence of antibiotic resistance among clinical strains of H. pylori, alternative approaches are increasingly needed. Methanolic extracts of Algerian originated Mentha rotundifolia, Eucalyptus globulus, Malva sylvestris, Inula viscosa, Achillea odorata and Utrica dioica and their contents of phenolics and flavonoids were evaluated for the in vitro antimicrobial activity against H. pylori in addition to its associated urease. The antimicrobial activity and determination of the MICs of these extracts against control strain of H. pylori was performed using standard agar diffusion method.  The highest phenolic and flavonoid contents were found in M. rotundifolia and E. globulus while M. sylvestris showed the least phenolic contents. In addition, polyphenolic fractions exhibited anti-H. pylori activity of all of the herbal extracts with  highest activity for E. globulus (MIC 0.094 mg/ml), I. viscosa, (0.375 mg/ml) and U. dioica (0.75 mg/ml), low antimicrobial activity was revield for  A. odorata, M. rotundifolia and Malva sylvestris respectively (MIC > 1 mg/ml).  For the urease activity, all extracts showed inhibitory effect at concentration of 250 mg/ml. However, the range of the urease inhibitory concentrations varied significantly among the extracts with highest activity and widest range found for E. globulus (70-90% at concentrations 8-125 mg/ml). In conclusion, the presence of potential antimicrobial activities in the polyphenolic extracts of medicinal plants against H. pylori and its associated urease would open the door for investigation of novel agents for the control of H. pylori infections