Iranian Journal of

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BackgroundsAandObjectives: Pseudomonas aeruginosa and Staphylococcus aureus are important pathogens that producewidespread infections. Purpose of this studywas to evaluate the antimicrobial effect of ultrasonic irradiation (US) alone and in combination with antibiotic on antibiotic resistance Pseudomonas aeruginosa and Staphylococcus aureus.
Materials and Methods: In this study ultrasonic irradiation (US) in a laboratory-scale batch sonoreactor with low frequency (42 kHz) plate type transducer at 170W of acoustic power was used. The Water samples, were taken from different wards of the 3 teaching hospitals which were affiliated to the Kurdistan University of Medical Sciences to isolate Pseudomonas aeruginosa and Staphylococcus aureus and also to determine their antimicrobial susceptibility pattern.
Results:Our results showed that Pseudomonas aeruginosa and Staphylococcus aureus were affected by the ultrasound and the bactericidal effect increased with time.
Conclusion: It was found that P. aeruginosa was more susceptible to the ultrasonic treatment than S. aureus. The combination of US with an antibiotic (amoxicillin) enhanced killing of both bacteria over the use of US alone. There were no differences in resistance to ultrasound between isolated strains and standard strains from persian type culture collection.

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MicrosoftInternetExplorer4 Background and Objectives: Nosocomial infection is the cause of deaths, morbidity, higher costs and increased length of stay in hospitals. Correct and appropriate use of antiseptic and disinfectants play an important role in reducing infections. In this study the efficacy of antiseptics on bacteria causing hospital infections has been studied.
Materials and Methods: This study was conducted in the laboratory of Imam Khomeini Hospital of Uremia. In this study the Antimicrobial activity of Descocid, Korsolex basic, Mikrobac forte and persidin 1% was studied against bacteria causing hospital infections such as Enterobacter aeruginosa 1221 (NCTC 10006), Staphylococcus epidermidis (PTCC: 1435 (Cip81.55) and Pseudomonas aeruginosa Strain PAO1. Sensitivities of bacteria were determined by Minimum inhibitory Concentration (MIC) and Minimum bactericidal Concentration (MBC) antiseptics. In the second stage, the concentration of antiseptics was prepared according to the manufacturer's suggested protocol and the effect of antimicrobial agents were studied at the certain concentration and contact time.
Result: All disinfectants (Descocid, Korsolex basic, Mikrobac forte) concentration and contact time, Accordance with the manufacturer's brochure, had inhibitory effect on all bacteria. That this is consistent with the manufacturer's brochure. Persidin one percent in concentration of from 2 and 4 V/V % and exposure time 5 minutes could not inhibit the growth of bacterial. But at concentrations of 10 and 20% respectively 15 and 30 minutes exposure time, all three types of bacteria can be inhibited, which is consistent with the manufacturer's claims.
Conclusion: In this study, the efficacy of antiseptics was determined with the Micro-dilution method recommended by the NCCLS. Korsolex basic, weakest antiseptics (the highest MIC) for the inhibition of three bacteria was determined. But Between all four antiseptics (according to manufacturer concentration), Only one percent Percidine 2 and 4 V/V %  in consumer dilution and 5 minutes exposure time failed to inhibit the growth of Pseudomonas aeruginosa, Staphylococcus epidermidis and Enterobacter aeruginosa.

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Background and Objectives: Organophosphate pesticides are used most commonly for domestic, commercial, and agricultural purposes and have been found to be highly toxic. In essence, bioremediation has become one of the most important tools for removing these compounds in the environment, considering its higher efficiency when compared with the physicochemical methods.

Materials and Methods: The biodegradation efficiency of two bacterial strains (i.e. Serratia marcescens BNA1 and Pseudomonas aeruginosa BNA2) were assessed. In order to evaluate Malathion biodegradation, each sample was cultured on mineral salts medium containing Malathion as a sole carbon source. Malathion biodegradation efficiency of the strains was monitored in different culture media. The ability of bacterial isolates to degrade Malathion was studied using gas chromatography.

Results: Serratia marcescens BNA1 and Pseudomonas aeruginosa BNA2 were able to degrade Malathion. Biodegradation percentage in different treatments recorded were: BNA1+Ma (33.88%), BNA2+MA (26.45%), BNA1+BNA2+Ma (46/96%), BNA1+Ma+Tween (61.05%), BNA2+Ma+Tween (40.17%), and BNA1+BNA2+Ma+ Tween (67.79%).

Conclusion: It could be speculated that the best degradation efficiency can be yielded using mixture of strains plus a surfactant. The results of this study can be used in the bioremediation of Malathion contaminate soil after doing the pilot experiments.