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Introduction: Phytase hydrolyzes phytic acid and enhances bioavailability of phosphorus and other nutritive minerals for monogastric animals, so it is commonly used as an important food additive. Materials and methods: The aim of this study was isolation of phytase producing bacteria from one of Shushtar's bean farms, Southwest of Iran by phytase screening medium (PSM) and optimization of the growth and enzyme productive conditions by the best isolate. Results: The best isolate was identified as Citrobacter farmeri strain phas32. Optimized conditions for phytase production by this isolate were 30˚C, pH 7, 0.25% phytic acid and 48 h incubation and phytase enzyme of phas32 had the best activity at 65˚C and pH 8.5. Enzyme unit and its molecular weight were 31 U/ml and 40 KD, respectively. Discussion and conclusion: Finally, based on these results it can be concluded that the Citrobacter farmeri strain phas32 is potent phytase producer that can be used for large scale enzyme production.

Introduction. Chlamydia trachomatis is mainly transmited by sexusal contact and similar to other STDs (sexually transmitted diseases) affect primarily young and sexually active persons which due to its undesirable effects in pregnancy is of great importance. The aim of this study is review the role of different C. trachomatis serovars and their relaition with infection consequents. Methods. This study was a review of data collected from scientific databases including Web of science, Google scholar, PubMed, Sciencedirect, ISC and magiran using the following keywords: Chlamydia trachomatis, serovar, STD, prevalence and infertility. After initial search with emphasis on the published English papers over the last 5 years, 66 articles were included. Results. The distribution of different strains of this intracellular bacterium in different parts of the world can be a suitable clue for planning epidemiologic programs for control of this infection and consequently other STDs. All studies on this subject nearly revealed that E serovar is the dominant serovar in the infection of cervix, vagina and uro-genital system but its prevalence varies between 20 – 50% in different researches. Conclusion. The distribution of serological groups of C. trachomatis around the wolrd is very similar at national scale but are different between cities. The most prevalent serovars are E, D and F. Various studies have shown the relation of serovars involved in urogenital infections with clinical symptoms severity and the duration of C. trachomatis infection; however contradictory data have been reported.

Endophytes are symbiont microorganisms within apoplast or symplast of plants that promote growth, control phytopathogens, increase plant resistance to stress and improve plant growth conditions. The aim of this study was identification of endophytes from six rice cultivars in Khouzestan province and assessment of their effects on growth of the host plant. For this purpose, a suspension was prepared from sterilized seeds, and their endophytes were isolated in LB broth. The ability of isolates in nitrogen fixation, auxin production and phosphate solubilizing was discovered. The seeds of Champa cultivar were then infected by endophytes and growth and physiologic outcomes of this treatment were studied. As a result of this study six endophytes belong to Bacillus, Staphylococcus and Erwinia genus were isolated from them only the Erwinia sp. was able to fix N2, dissolve phosphate and produced auxin more than others. Treatment with Erwinia sp. significantly increased the fresh and dry weight of aerial parts and root and aerial part length and density of hair roots. The auxin and carbohydrate content of treated rice with Erwinia sp. had significant difference than control. No significant difference was observed for chlorophyll a and b chlorophylls in different treatments and untreated plants produced more a and b chlorophylls. While there was significant difference for carotenoid between endophyte treated samples and untreated ones. Finally based on the obtained results it can be suggested that Erwinia sp. as an endophyte has significant effect on increasing of Champa cultivar performance and improvement main characteristics of this cultivar.

The triazole core is an important part of the therapeutically drugs such as antimicrobial, analgesic and anti-inflammatory agents. Therefore, a facile synthesis of a series of 1,2,3-triazoles has been introduced by the sequential azidation of alcohols or epoxides and then Cu (I)-catalyzed azide-alkyne cycloaddition (CuAAC) in water. The biological profiles of some of these five-membered heterocyclic scaffolds toward anti-bacterial activities were evaluated using Kirby-Bauer Disc Diffusion method. The biological obtained results were very interesting and revealed that most of the examined molecules are potent antibacterial agents when compared with standard drugs.

Municipal and industrial effluents continually release into the environment heavy metals of a variety of physical and chemical forms and at various concentrations. Biological treatment processes have attracted a growing attention for the removal of heavy metals from these effluents. For the purposes of the present study, bacteria that are relatively resistant to heavy metals, such as cadmium and lead, were isolated from municipal waste and purified. They were then subjected to biochemical tests for identification and their minimum inhibitory concentrations were determined. Bacterial minimum inhibitory concentrations were initially measured in flasks containing 25, 50, 75, 100, 150, 300, 500, and 700 ppm of lead and cadmium before superior bacteria at populations of 108 CFU/ml were evaluated in terms of their ability to remove lead and cadmium at concentrations of 50, 100, 150, and 300 ppm from enriched municipal wastewater. Base on the results, Bacillus laterosporous and Yersinia pseudotuberculosis were identified as the resistant bacteria and the minimum lead and cadmium inhibitory concentrations for these bacteria were determined to be 300 and 500 ppm, respectively. Moreover, Bacillus laterosporous and Yersinia pseudotuberculosis recorded maximum removal efficiencies of around 50.6% and 45.7%, respectively, with wastewater containing 100 mg/l of lead and 36.18% and 21.41% in the case of cadmium from wastewater enriched with 100 mg/l of lead and 150 mg/l of cadmium.

Introduction: Polyhydroxyalkanoate (PHA) is counted biodegradable polymer, produced by bacteria, which is employed instead of petrochemical plastics, to reduce environment pollution. The purpose of this study is the isolation and identification of the PHA producing bacteria in Masjed-Soleiman oil fields, determination of PHA produced by the bacteria, determine the optimal conditions of temperature, pH, concentration and type of carbon and nitrogen sources on the level of PHA synthesis and the use of waste oil as a cheap substrate of carbon for the synthesis of PHA by isolated bacteria. Materials and methods: At first 9 samples of soil contaminated with crude oil, from 9 points at 4 well sites in Masjed-Soleiman oil field were taken. The initial screening was done by MSM at the temperature of 28 °C. Isolates from the view point of producing PHA, were confirmed, by using Sudan black stain and were identified by using phenotypical tests and 16S rRNA sequence determination. Also, optimization of temperature, pH, carbon and nitrogen sources were made for bacteria growth. Results: In this study eleven isolates were identified as PHA producers and among them the highest range belongs to MIS-1 strain by the range of 58.522 percent of the cellular dry waight, wich produces the maximum PHA. This isolate is recognized as the species of pseudomonas aeroginosa according to the phenotypic tests and sequence analysis of 16S rRNA with 95 % similarity. In addition, the results of optimization tests showed that, the isolates in the temperature of 37 °C, pH7, glucose as the source of carbon and ammonium sulphate as the source of nitrogen and finally, concentration of 10 g/lit of the carbon source and 0.5 g/lit of nitrogen source, the highest range of PHA was synthesized. Discussion and conclusion: The results of this research show that the soil polluted with crude oil of Masjed- Soleiman oil field, in long term and also due to high rate of carbon, provides a suitable environment for screening of beneficial bacteria such as PHA producing bacteria.

Introduction : Environmental contaminations due to petrochemical plastic usage have forced researchers to search new biological methods for biodegradable polymer production. The aim of this study was to find native PHA producing bacteria from Abadan oil refinery in order to be used in biodegradable polymer production studies. Materials and method s : For this purpose soil samples were harvested from oil sludge contaminated soil of Abadan refinery. After primary enrichment, screening of PHA producing bacteria was done by PHA- Detection agar and was confirmed by Sudan black and Nile Blue A staining methods. These isolates were identified based on phenotypic methods and sequencing of 16s rRNA. Polymer extraction was performed and optimized using different concentrations of HClO and SDS. Results : As a result of this study 26 different bacterial isolates were obtained from which 17 isolates were PHA producer with different potentiality. Based on the polymer accumulation 4 isolates were selected for further studies. The efficiency of PHA production in these isolates was 75.53±5.08, 82±19.05, 81.06±6.92 and 79.86±11.84%. Based on sequence analysis in NCBI database, these isolates were identified as Bacillus cereus. Discussion and conclusion : With respect to the results of this study it can be suggested that oil contaminated soils due to high C/N and C/P ratios and also different carbohydrate contents are suitable candidates for PHA producer bacteria isolation. So the native strains in such habitats with high carbon content can be optimized for industrial polymer production.

Introduction: “Bioremediation” is one of the most effective methods to remove petroleum contaminants. The aim of the present study is to isolate the indigenous bacteria from the waste petroleum in the Masjed Soleiman No. 9 production tank and to examine the effect of their application on the elimination of petroleum heavy chain hydrocarbons and converting them into light compounds . Materials and methods: Two percent of petroleum sludge was inoculated to the mineral basal medium and after proliferation of its indigenous bacteria, they were inoculated into the mixture of oil sludge and sand at level of 5%, and the amount of total hydrocarbons and residual oil were measured and compared. The isolates were identified based on biochemical tests and 16S rRNA gene sequencing. Optimization of nitrogen and phosphate sources was done based on growth curves of selected isolates. Gas chromatography was used to determine degradation of sludge hydrocarbons. Results: In this study, 10 bacterial isolates were isolated from petroleum sludge . Measurement of petroleum total hydrocarbons, using Soxhlet-extraction method, showed that two isolates named MIS1 and MIS2 are able to decompose oil sludge hydrocarbons within 7 days, with the yields of 62% and 72%, respectively. Furthermore, the two isolates reach the end of the logarithmic phase at 48 and 120 hrs, respectively. The best source of nitrogen and phosphate for both isolates was ammonium nitrate and potassium di ­hydrogen phosphate, respectively. The isolates were identified as Arthrobacter aurescens and Pseudomonas aeruginosa , respectively. In gas chromatography analysis it was revealed that Pseudomonas aeruginosa was more potent in degradation of heavy chain hydrocarbons and their conversion to light chain compounds. Discussion and conclusion: Resident bacteria are present in the oil sludge and are able to degrade the heavy petroleum compounds and convert them into light compounds. These bacteria are effective in the reduction of environmental pollution and production of low molecular weight hydrocarbons.

Khuzestan Province accommodates the largest oil-fields with huge petroleum production in Iran. During the Persian Gulf war in 1991, more than 6-8 million gallons of oil was spilt in the Persian Gulf, the greatest amount of which was transported into Khuzestan soil. Thus, oil removal from contaminated soil by advanced technologies such as bioremediation seems to be of vital necessity. The aim of this study was to evaluate the effect of sewage-sludge application on bioremediation of oil-contaminated soil. Soil samples (5kg) were artificially contaminated with crude oil to a level of 1000 mg/kg. Sewage sludge treatments were applied at the 3 levels of 0, 100, and 200 gr/5kg soil in 3 replicates. The soils were kept in the normal moisture aerobic environment for 5 and 10 weeks. The soils were then analyzed for Hydrocarbon-degrading heterotrophic bacterial count. Oil extraction from the samples was accomplished using the oil Soxhlet extraction method and oil degradation was measured by GC chromatography. The results showed that the hydrocarbon-degrading and heterotrophic bacterial counts in all the treatments increased with time. Results indicate that heterotrophic bacterial population increased from 6×103 cfu/gr soil to 2×1010 cfu/gr soil. Also, C/N ratio decreased from 6 to 3. GC results indicated that all normal Alkanes and Isopernoids, i.e. Phytane and Pristane, decreased by 50-90 percent in all the treatments. It was also found that the application of sewage sludge at 100 gr/5kg soil to oil-contaminated soil leads to greater rates of biodegradation after 5 weeks