disinfecting potential of contact lens solutions used by Sultan Qaboos university students

This study aimed to determine the disinfecting potential of some contact lens solutions used by some university students in Oman. This work was carried out from January to June 2010 in the Department of Microbiology and Immunology, College of Medicine and Health Sciences, Sultan Qaboos University, Oman. Fifty disinfecting solutions, in which contact lenses were disinfected according to the manufacturers' instructions, were collected from the students and plated on various microbiological culture media. Bacterial isolates were identified by API-20E, API-20NE and Phoenix automated systems while fungi were identified by their cultural characteristics and biochemistry. From 98 isolates, Pseudomonas aeruginosa was 23.5%; Penicillium, 13%; Candida species, 9.2%; coagulase negative staphylococci, 9.2%; Serratia marcescens, 6.1%; Bacillus, 5.1%; Aspergillus flavus, 5.1%; Serratia liquefaciens, Pseudomonas fluorescens, Enterbacter cloacae and Aspergillus niger, 4.1% each; Chryseomonas luteola and chryseomonas indologenes, 3.1% each; Stenotrophomonas maltophilia, Serratia odorifera, 2.0% each; enterobacter aerogenes and Klebsiella pneumoniae, 1% each. Most isolates [65%] came from polyhexanide containing solutions. Contact lens disinfecting solutions with the same formulations, but manufactured by different companies, possessed different disinfecting potentials

Antimicrobial activities of clove and thyme extracts

It has been postulated that geographical locations of the herbs affect the constituents of their essential oils and thus the degree of their antimicrobial action. This study examine two samples of clove obtained from Sri Lanka and Zanzibar and two samples of thyme from Iran and Oman to determine the antimicrobial potential of their extracted oils. The active agents in each plant were extracted by steam distillation and by boiling. The antimicrobial activities of the extracts were determined at neat and by two-fold dilutions in well agar diffusion technique using Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Streptococcus pyogenes, Corynebacterium species, Salmonella species, Bacteroides fragilis and Candida albicans. All oil extracts possessed antimicrobial activity against all bacteria and yeast tested. Their water extracts exhibited lower antimicrobial activity, though thyme aqueous extract was active only against S. aureus. The lowest concentration of antimicrobial activity [0.1% i.e., 1:1024] was obtained with thyme oil extract using Candida albicans. There was no significant difference in antimicrobial activity between clove obtained from Sri Lanka or Zanzibar or thyme obtained from Iran or Oman. Our experiment showed that the country of origin of the herbs has no effect on their antimicrobial activity. However, further work is necessary to ascertain why Candida albicans displayed remarkable degree of sensitivity with the extracts than all the other organisms test

Antimicrobial potential of honey on some microbial isolates

To determine the extent of rickettsial infections prevalence of potential vector ticks in the rural population of Dhofar, Oman. Human sera [n = 347] were obtained from six rural localities [school children, farmers, outpatients] in Dhofar, Sultanate of Oman. Sera were tested by mmunofluorescence for the presence of antibodies reacting with Rickettsia conorii antigen. More than half the samples [59%] gave positive reactions [titres of at least 1:64]. Ticks [n = 707] were collected from cattle, camels and goats [n = 102] and included Amblyomma variegatum, Hyalomma a. anatolicum, H. dromedarii, H. rufipes and Rhipicephalus spp., all of which can potentially transmit rickettsiae to humans. The results suggest that rickettsial infections are common among the rural population of Dhofar

Carrier status of group B streptococci among some pregnant women attending sultan gabnoos University Hospital

Group B streptococci has been associated with neonatal sepsis resulting in neonatal septicaemia, meningitis or pneumonia. The organism is also a normal flora of the vagina. This study is to determine the prevalence of this organism among pregnant women attending the Sultan Qaboos University Hospital with the objective of linking the finding with any neonatal sepsis. Materials and High vaginal swabs in Stuarts transport medium were collected from pregnant and non-pregnant women and cultured on gentamicin blood agar plates which were incubated in C02 overnight. Colonies suggestive of group B streptococci were identified using antisera to polysaccharide C antigen of Streptococcus group. The result indicates that 18 [14.3%] and 16 [20.8%] of pregnant and non-pregnant women respectively had group B streptococci. The highest carrier rate [42.4%] was found in women between the ages of 19 and 28, while women above 49 years were all negative. Discussion/The study indicates that women at sexually active ages [19-28] had the highest carrier rate. There was no significant difference in carrier rate between pregnant and non-pregnant subjects and no neonatal or perinatal sepsis was reported during the period of the investigation. We therefore feel that group B streptococci as a major cause of neonatal sepsis may be very low in Omani pregnant women. Further investigation is necessary to confirm this observation