فصلنامه دنیای میکروب ها
پیاپی 1 (زمستان 1387)

Today use of microorganisms for removing crude oil pollution from contaminated sites (bioremediation) was considered by scientists because other methods such as surfactant washing and incineration lead to production of more toxic compounds and they are non-economic. Fifteen crude oil degrading Bacillus spp. were isolated from contaminated sites. Two isolated showed best growth in liquid media with 1-3% (v/v) crude oil and mineral salt medium. The results show maximal increase in optical densities, total viable count and total protein concomitant with decrease in pH on fifth day of experiment period for Bacillus S6. Typical generation time on mineral salt with 1% crude oil is 18h and 25-h respectively for Bacillus S6 and S35. These bacilli reduce surface tension from 60 (mN/m) to 31 and 38 (mN/m) it means that these bacilli can produce sufficient surfactant. Total of carbon, nitrogen and hydrogen was measured before and after of treatment by using ASTM D5291 method. The results reflect that total of carbon was decreased from 85.6 (mass %) to 41 and 48.8 (mass %) respectively by Bacillus S6 and S35. Biodesulfurization of crude oil was investigated by using IP 242 method. After one month of treatment at 30°C, 42% and 80% of total sulfur content was removed respectively by Bacillus S6 and S35. Quantitative analysis using gas chromatography carried out to demonstrate the effect of biodegradation on n-alkanes (C13-C30). In our study the amounts of hydrocarbons lost by biological processes. The results confirm that isolated Bacillus can use crude oil as source of carbon and energy.

Enteroviruses are one of the most important enteric viruses which produce a broad range of human diseases. But being time consuming and also the necessity to perform confirmed tests for Enteroviruses detection, using molecular direct methods have been recently considered. The aim of this research is evaluation of ICC-RT-PCR and cell culture methods for detection of enteroviruses in sewage system. In this research 63 specimens were provided through Grab sample method which concentrated by pellet & Two-phase method and cultured in RD and HEp-2 cells respectively. All specimens, then, were inoculated using sensitive cell cultures of RD and HEp-2. After 24 hours incubation at 360C by means of Pan E.V primers and afterwards Pan P.V Primers along with specific sabin primers, test of RT-PCR was carried out on the cell culture specimens. Out of all collected specimens, enteroviruses were isolated from 33 specimens (52.38%) and 41(65.01%) specimens which utilized cell-culture & ICC-RT-PCR methods respectively. Polioviruses were also isolated from 6 specimens. Statistical analysis indicated that there is a significant relationship (p= 0.05) between cell culture and ICC-RT-PCR methods for isolating enteroviruses. Further the sensitivity of ICC-RTPCR method to detect enteroviruses less than 0.01 TCID50 was evaluated, which can indicated the acceptability and sensitivity of this method for detection of enteroviruses in sewages.

Jail prisoners with or without drug addiction is an high risk population for affecting of different blood born viral complications like hepatitis type C virus (HBV) infection. Then, in this research the seroepidemiological prevalence of HCV infections and also the possible role of different risk factors of HCV complications were evaluated in jail prisoners of Sharekord. In this investigation, the plasma samples of 600 Sharekord jail prisoners were collected and preserved in -20°C. The prevalence of HCV-Ab was monitored by a third generation ELISA protocol in these plasma samples. The possible role of different HCV risk factors like: sex, marriage, history of drug injection, and types of drug addiction, history of prisonership, history of tattooing, transfusion of blood and blood products, unethical sex relationship, and the knowledge of prisoners from the route of HCV transmission were statically analyzed by SPSS and Instat soft wares. HCV-Ab was diagnosed in seventy six of 600(12.66%) jail prisoners by ELISA method. Also the relationship of HCV infection with different risk factors including: sex, marriage, history of drug injection, and types of drug addiction, history of prisonership, history of tattooing, transfusion of blood and blood products, unethical sex relationship, and the knowledge of prisoners from the route of HCV transmission were as follow: 8.16%, 10.66%, 5.83%, 9.16%, 7.33%, 0.33%, 2.16%, 1.0%, and 10.5%. Significant associations were not detected between HCV infections with sex, marriage, transfusion of blood and blood products, unethical sex relationship and knowledge of prisoners from the route of HCV transmission. But significant associations were detected between HCV infections with history of drug injection, and types of drug addiction, history of prisonership, tattooing, and age grouping. Detection of significant associations between HCV infections with history of drug injection, and types of drug addiction, history of prisonership, tattooing, and age grouping, and diagnosis of insignificant associations between HCV infections with different HCV risk factors and also diagnosis of different prevalence of HCV-Ab in jail prisoners announced the need of completed study in other jail populations.

Predominant organisms in plaques are of the genus Streptococcus, withStreptococcus mutansbeing the species most important in the formation of dental caries. Another organism that is important in the development of caries is the lactobacillus. Lactobacillus species are not important in the initiation of caries but in the continuation. The aim of this study was to isolate and identify of lactic acid bacteria from the mouth in different ages, determination of pH and study the inhibitory effect of isolated Lactobacilli on some entropathogens bacteria (Salmonella, Shigellaand Escherchia coli). From 75 persons in different ages, the samples were collected from saliva and around dental and were cultured in MRS medium. Lactobacilli and Streptococci were isolated and identified by standard methods (morphology, microscopic shape and chemical characteristics and fermentation of carbohydrates). Growth pH of isolated Lactobacillus was determined. Inhibitory effects of isolated bacteria were evaluated by spot on the lawn, blank disk and well-diffusion methods on Salmonella, Shigellaand Escherichia coli. Isolated Lactobacillus were including L. fermentum, L. casei, L. gasseri, L. brevis, L. plantarumand L. acidophilus, and isolated Streptococci was Streptococcus mutans. Isolated Lactobacilli had inhibitory effect on Escherichia coli but they didnt have any inhibitory effect on Salmonella andShigella. Our results showed that some Lactobacilli had inhibitory effect on some pathogenic in vitro. So, consumption of dairy (because of the presence of Lactobacilli) is recommended.

AFP (Acute flaccid paralysis) is a suddenly weakness of any organs ofbody that its symptoms reach to peak after 4-5 day, but it dont progress. AFP has much etiology that Poliovirus is more important than others. At currently, Poliovirus has been eradicated in most countries, and then we must analysis role of nonpolio agent in this disease. In this work, all of stool specimens of AFP patient (2003) inoculate to five cell line (L20B, RD, Hep-2, Vero and GMK). And have evaluted with micronutrilization tests. We inoculate two specimens from any 460 case fewer than 15 years AFP patient to these five lines. Ultimately, we isolated 34 different species and serotypes of Entroviruses. Upon this result, 7.1% of all cases were positive for cell culture and isolation of Entroviruses. Sexuality doesnt have an effective role in isolation of Entroviruses. Most of these viruses isolated from less than 0-5 year's children and it decline by increase in age. Echoviruses (12 cases) and Polioviruses (12 cases) have been isolated more than others. We showed a meaningful difference between RP (Residual Paralysis) positive and RP negative cases. Upon this result, we showed nonpolioEntrovirusescan cause RP. It doesnt have meaningful difference isolation of Vaccine Poliovirus between RP positive and RP negative patient. Then we showed OPV vaccines used in Iran, have enough safety. The difference in isolation of Coxsacievirus between RP positive and RP negative is not meaningful. We demonstrate Echoviruses can cause AFP in patient fewer 5 years, because the difference in isolation of Echoviruses between RP positive and RP negative patient is meaningful.

Mercury is one of the most toxic heavy metals. Even small amounts of mercury are highly toxic for all organisms, but some bacteria are resistant to mercury using special mechanisms. The aims of this study were isolation and identification of mercury resistant bacteria and survey of relation between levels of environment pollution to mercury and isolation of resistant bacteria. The samples were collected from water and sediments of four stations of KorRiver in four seasons from summer 2006 to spring 2007. Amount of mercury in the samples were measured. Bacterial numbers in both medium containing mercury and with out mercury were enumerated. Isolation of mercury resistant bacteria was performed using primary enrichment and direct plating on agar. The bacteria were identified with conventional biochemical tests. The number bacteria in the medium with out Hg was 1×107CFU/ml or CFU/g and more than medium containing Hg. Frequencies of mercury resistant bacteria was 54.2 % in PloeKhan station and 4.3 % in Droodzan station. These stations were the most contaminated and uncontaminated areas of the Kor River Respectively. Different bacterial genera such as Pseudomonas sp., Staphylococcus aureus, Bacillus sp., Entrobacter sp., Klebsiella sp., Serratiamarcescensand etc. were identified as mercury resistant bacteria. Our study showed utilization of primary enrichment in comparing to the direct plating on agar lead to better isolation of mercury resistant bacteria. Moreover, enhancement of mercury levels in the environment will increase the probability of the isolation of mercury resistant bacteria.

Nowadays, the synthesized biopigments by bacteria possess enormous efficiency as medicinally important products. One of the most important biopigments is tripyrrole red pigment of Serratiamarcescens that is called prodigiosin. Resent studies reported antifungal and anticancer activity for them. The aim of this work from an industrial point of view is the necessity of obtaining a suitable medium to enhance the growth of Serratiamarcescens and the pigment production. In this research Serratiamarcescens PTCC 1111 was used. The enhancement of prodigiosin production on Peanut broth, Sesame seed broth, TSB, BHI and nutrient broth medium at 24, 28, 30 and 37C by UV Spectrophotometer method at 535 nm was investigated. In the next process, Serratiamarcescens grow in peanut broth was centrifuged at 10,000 rpm and by using organic solvents such as acetone, ethyl acetate, sodium sulphate, chloroform, dichloromethane and column chromatography, pigments got purified. The result of this research determines the optimum situations for pigment production as follow Temperature 28C, Culture medium: Peanut seed broth containing significant fatty acid source. The results of pigment purification showed only one peak by using UV Spectrophotometer at 535 nm. With regard to importance of biopigment application, optimization in large scale is recommended.

Viral infections like hepatitis type B virus (HBV) is one of the main causes of blood born microbial complications in high risk groups especially jail prisoners with or without drug addiction. However, in this research the prevalence of HBV infections and also the possible role of different risk factors in HBV presentation were studied in Sharekord jail prisoners. In this retrospective study, the blood samples of 600 jail prisoners were collected and their plasma were isolated and stored in -20°C. The prevalence of HBsAgwas determined by a third generation ELISA method in these collected samples. Also the possible role of different HBV risk factors like: sex, marriage, history of injected or un-injected drug addiction, prisoner ship history, history of tattooing, transfusion of blood and blood products, unethical sex relationship, and the knowledge of prisoners from the route of HBV transmission were statically analyzed by SPSS and Instat soft wares. HBsAg was detected in 90 of 600(15%) jail prisoners. Also the relationship of HBV infection with multiple risk factors including: sex, marriage, history of injected or uninjecteddrug addiction, prisoner ship history, history of tattooing, transfusion of blood and blood products, unethical sex relationship, and the knowledge of prisoners from the route of HBV transmission were as follow: 14.66%, 9.5%, 7.34%, 3.17%, 4.66%, 4.0%, 1.16%, 1.0%, and 8.66%. Significant associations were not detected between HBV infections with history of drug addiction and types of drug addiction, prisoner ship history, unethical sex relationship and knowledge of prisoners from the route of HBV transmission. But significant associations were detected between HBV infections with tattooing and transfusion of blood and blood products. Detection of significant associations between HBV infections with tattooing and transfusion of blood and blood products and insignificant associations between HBV infections with different HBV risk factors and also diagnosis of different prevalence of HBsAg, announced the need of completed study in other jail populations.