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Abstract Skin wounds have the potential to rapidly become infected, with bacteria having the ability to quickly penetrate to the skin’s deeper layers. Then they enter the lymph nodes and spread throughout the body; therefore, all wounds should be cleaned and have a permanent cover. Modern wound dressings with effective antibacterial and therapeutic properties are required to create a sterile environment for the acceleration of healing. The aim of this work was to prepare zein electrospun nanofibers containing Scrophularia striata extract for wound healing promotion. Electrospun nanofibers made of zein, a natural polymer, have attracted a lot of attention due to their biocompatibility and biodegradability. The prepared nanofibers were characterized by scanning electron microscopy (SEM), energy dispersive X‑ray analysis (EDX), water contact angle test, and Fourier transform infrared spectroscopy (FT-IR). The parameters affected by the electrospinning process were investigated and optimized. The results revealed that the zein nanofibers (25% w/v, zein) containing Scrophularia striata extract (6.7% w/v) had a smooth and bead-free morphology with improved surface hydrophilicity. The measurement of water contact angle confirmed that nanofibers containing extract showed higher wettability (64.9°) compared to fibers without extract (119.8), so the proposed mat adequately moisturizes the wound environment. The antimicrobial studies show that Scrophularia striata extract incorporated nanofibers has the ability to inhibit the growth of both gram-negative and gram-positive bacteria. The biophenols release profile indicated that nanofibrous mat can release more effective substances to promote wound healing. The biocompatibility and biodegradability of nanofibrous scaffold containing Scrophularia striata extract tested in in vivo and in vitro conditions show a significantly higher survival rate of fibroblast cells. In addition, macroscopic and histological observations confirmed that the implanted nanofibers containing the extract did not exhibit any signs of inflammation or redness after a month when inserted beneath the skin of mice surrounded by vessels containing epidermis. Graphical Abstract

Damage to the skin and creating a wound can always cause problems for the human body. Therefore, to repair the wound, the medical industry is looking for different methods to repair and regenerate the damaged tissue. One of the promising methods is tissue engineering and polymer scaffolds, including hydrogels. Chitosan and alginate are natural polymers widely used for wound healing and hydrogel preparation due to their excellent properties. Adding natural compounds such as essential oil and nettle (Urtica dioica) extract to hydrogels can effectively accelerate wound healing. Using nanocarriers such as nanoemulsions and putting nettle oil and extract in these systems can increase their efficiency in hydrogel structure and more effective wound healing. This study combines nanoemulsions containing nettle extract and oil in chitosan/alginate hydrogels, resulting in promising wound dressing materials. The findings show that these nanocomposites exhibit effective inhibition of bacterial growth, minimal cytotoxicity, increased cell adhesion, exceptional water absorption capabilities, and remarkable blood compatibility.

One of the most important causes of soil desertification is wind erosion. Deserts are known for their poor physical, chemical, and biological properties. In order to solve the problem of loose sand, many solutions have been thought and used so far. Today, scientists have greatly benefited from the capabilities of MICP in the field of sand dune stabilization, which seems to be an environmentally friendly solution. In Khuzestan, a lot of "vinasse" enter the environment every year, which is considered a pollutant. Combining it with beneficial native microorganisms can turn it into a valuable ingredient. The objectives of this study were to investigate the microbial activity of bacteria isolated from the sand dunes of Khuzestan in Iran using vinasse as a carbon source for growth. In order to eliminate the effect of competition and investigate the activity of the studied bacterial isolates (Bacillus licheniformis MZ057843, MZ057842, OP329211, and Sporosarcina pasteurii), the samples of sand dunes collected from Khuzestan were first sterilized. Then, inoculated vinasses were added to them, and the prepared samples were incubated for five weeks. The experiments (counting bacteria by plate count technique, Soil catalase by the method of titration with KMnO4, and Soil microbial respiration by measuring the amount of CO2) were measured after the first, third and fifth weeks of incubation time. Then, the data were analyzed by split plot in time design. The current study showed significant effects of vinasse, bacteria, time and their interaction in all three tests (p < 0.0001). Isolate B1 was able to cause the highest amount of microbial population and microbial respiration, and isolate B3 produced the highest amount of catalase enzyme in the soil. Among the three types of vinasse, V3 had the highest amount of catalase and microbial population, and V2 had the highest soil microbial respiration rate. The best incubation time for the microbial respiration and population tests was the first week, and third week of incubation for the catalase test. Generally, native Bacillus bacteria grew in vinasse as a carbon source and perhaps the potential of vinasse as a mulch can be explored. However, more research is needed to use it in soil stabilization operations.

Background and Objectives: Rumen microbiologists are looking for new probiotics to improve the digestibility of livestock diets. This study intended to screen and evaluate the ruminal cellulolytic bacteria (CBs) and their potential application as probiotics. Materials and Methods: Microbial culture and molecular techniques performed to isolate CBs from the rumen of camels, deer and rams. Their antibacterial and antibiogram tests were done using disc diffusion method. Their potential to degrade cellulose, starch, tannin and protein were investigated using clear zone halo, and spectrophotometric techniques. Bilious, saline, and acidic broth media were used to study the resistance of isolates in intestinal conditions. Results: The phylogenetic analysis revealed that the strains belonged to Firmicutes and Proteobacteria phyla, Citrobacter murliniae, Ornithinibacillus bavariensis, C. braakii, and Bacillus subtilis. The highest cellulase (CAS) activity was recorded by C. murliniae Dez wildlife13A (2.98 UmL-1), whereas C. braakii Loot desert 111A (1.14 Uml-1) was produced the lowest enzyme. The isolates were highly resistant to synthetic conditions of intestine (pH 2.5-3.5, bile 0.3-2%), as well as tolerated higher concentrations of NaCl (up to 10%). They effectively inhibited standard pathogen strains, and showed sensitivity to the used antibiotics. Conclusion: This study reports the cellulolytic O. bavariensis Tabbas desert 32A for the first time from the rumen, which will have potential biotechnological applications.

Introduction: Staphylococcus aureus is among the primary cause of hospitals and community-acquired infections. The emergence of methicillin-resistant S. aureus (MRSA) strains has resulted in the treatment failure of the infections caused by these bacteria. Hence, regional data on antibiotic resistance of S. aureus strains is necessary to adopt appropriate treatment regimens. This study aims to identify the diversities and their frequencies among MRSA isolates by molecular analysis of four genes. Methods: In a cross-sectional study, 100 S. aureus isolates from patients hospitalized in two hospitals of Ahvaz, Iran were collected and identified. The MRSA isolates were identified by phenotypic method and amplification of the mecA gene. The diversity of MRSA isolates was investigated by amplification of the coa, spa, aroA, and gap genes followed by RFLP analysis using the AluI, HindIII, TaqI and RsaI restriction enzymes. Results: In this study, we identified 50 MRSA isolates. Based on the analysis of coa gene, 8 types, spa gene 5 types and 17 subtypes, coa gene with AluI 13 types, and spa with HindIII 13 types were identified. Also, the RFLP analysis of gap gene with AluI revealed 3 types, and of aroA gene with TaqI and RsaI, 3 types and 2 subtypes, respectively. Conclusion: Our PCR-RFLP analysis revealed that diversities are present among MRSA isolates originated from clinical samples and showed that this method is simple, reproducible, and cost-effective.

Abstract Karoon River is the most important river in Iran that supplies the drinking and industrial water to many cities and villages in Khuzestan. As a consequence of hospital and municipal wastewater discharge into this river, antibiotic resistance will be increased in microbial inhabitants of this ecosystem. Furthermore, microbial load is also undergone continual variation. The aim of this study was to evaluate seasonal microbial quality and antibiotic resistance in bacterial isolates. For this purpose, five stations were selected and samples were harvested during four seasons. Bacterial count was performed through culturing on Mueller–Hinton agar, and bacterial isolates were identified. Antibiotic resistance profiles of isolates as well as resistance to Hg were investigated. As a result, it was found that the least quality was in summer season while the best quality was in winter that is related to the reduction of water volume and recreational activities in summer and increasing rain and dilution of contaminants in winter season. All isolates were sensitive to Hg while antibiotic resistance and multidrug resistance were found in bacterial isolates. Based on the obtained results, it can be concluded that the microbial quality of Karoon River has variations depending on the season and it is necessary that be monitored in order to control and prevent epidemic bacterial infections and antibiotic resistance distribution.

Background and aims: Infectious diseases are among the most important causes of mortality around the world and according to the WHO report 10.5 million cases of death were happened due to infections. Staphylococcus aureus is one of the most important pathogen that its infections are varied from local infections to life threatening infections. With regard to high antibiotic resistance of this agent its control and treatment is a challenge in medicine. The aim of this study was to review the effective medicinal plants against S. aureus with special attention of native plants of Iran.Methods: A comprehensive literature review was performed on papers that have been published from 2004 till 2016 in data resources such as NCBI, Sciencedirect, Springer, Web of science and as well as local databases such as Irandoc, Islamic science citation (ISC) and magiran with special focus on those that have been reported native medicinal plants in Iran. The selected keywords were Staphylococcus aureus, medicinal plant, natural antibiotic, antibacterial plant and medicinal herbs.Results: Different studies were found that have reported effective medicinal plants against S. aureus and were able to significantly inhibit bacterial growth. As well as different parts of these plants have been investigated for antibacterial activity and found that considerable differences are present among these parts of plants.Conclusion: Based on the reported studies, there are different medicinal plants in Iran that can be regarded as effective source for discovery new antibacterial agents against S. aureus and treatment of resistant strains.

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.

Resistance to methicillin in methicillin resistant Staphylococcus aureus (MRSA) is dependent on mecA gene located on staphylococcal cassette chromosome (SCC). Both SCCmec type and Panton-Valentine leukocidin (PVL) affect S. aureus pathogenicity. Aim of this study was to investigate the prevalence of SCCmecA types and pvl genes among MRSA isolates from inpatients. During this cross-sectional study on 100 clinical isolates, following antibiotic susceptibility test, screening of mecA and pvl genes, as well as SCCmec typing, was done in a multiplex PCR technique. From the studied samples, 58 isolates were recognized as MRSA. The frequency of mecA and pvl was 58% and 4%, respectively. All of the MRSA were resistant to cefoxitin and had the highest sensitivity to chloramphenicol. The majority (77.5%) of MRSA was originated from wound samples. The SCCmec III was the most frequent type (22.4%) in these samples. The pvl positive isolates were from SCCmec IVb and V, thus meaning they are from CA-MRSA. These results show a high prevalence of MRSA in the studied region and a widespread prevalence of SCCmec I-V types. Furthermore, high prevalence of SCCmec III indicates the prevalence of multidrug resistant MRSA. This finding is a serious alarm for medical health care practitioners for the correct use of antibiotics in order to limit the spread of multidrug resistant strains. In addition, with regard to life threatening infections caused by pvl harbouring strains, early diagnosis and treatment of infections caused by these isolates should be mandatory.

Background and Objectives: Fibrinolytic drugs are commonly used for fibrin clot lysis but due to their inappropriate side effects, as well as their high costs, using fibrinolytic enzymes has been paid attention. Bacterial sources of this enzyme are a good alternative for this purpose. The aim was fibrinolysin production through screening of fibrinolysin producing bacteria from environmental samples. Materials and Methods: Bacterial isolation was performed from different environmental samples and was screened based on sheep blood clot digestion and culture on plasma plate. The most potent isolate was optimized for different growth parameters including temperature, pH and fibrinolysin production at optimum growth conditions. The stability of produced enzyme at various temperatures and pH and treatment with MgSO4, NiSO4, SDS and EDTA was then investigated. Finally this isolate was identified based on the 16S rRNA sequencing. Results: As a result, from 79 different isolates, the most potent fibrinolysin producer was identified as Alcaligenes faecalis strain 26. This isolate produced 12 mm halo zone on plasma plate. Its optimum growth temperature and pH was 43°C and 7, respectively. The produced enzyme had the best stability at pH 7 and was also active up to 60°C. The fibrinolytic activity of this isolate was reduced following treatment with MgSO4, NiSO4 and also with protease inhibitors, such as SDS and EDTA. Conclusion: Based on the obtained results it can be suggested that Alcaligenes faecalis strain 26 has appropriate efficiency for fibrinolysin production that can be used in food industry and medicine.

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.

ABSTRACT Nanoparticles due to their unique properties have attracted more attention and their bacterial biosynthesis is more favorable because is environmental friendly and the size and yield of nanoparticles can be optimized. The aim of the present study was biosynthesis of Selenium nanoparticles using Bacillus cereus. For this purpose, bacterial culture was prepared in the presence of sodium selenate solution and incubated (30°C, 24 h). The produced nanoparticles were purified through consequent centrifugation, washing with 0.9% NaCl, sonication, washing with Tris- HCl containing Sodium dodecyl sulfate (SDS) and finally isolation with water- octanol two phase systems. Then using Ultraviolet-Visible spectroscopy, dynamic light scattering (DLS), scaning electron microscopy (SEM) and X-ray diffraction (XRD) analysis, nanoparticle production was confirmed. The bioavailability of nanoparticles was also investigated in rat. As a result of this study spherical selenium nanoparticles with a mean diameter of 170 nm were biosynthesized. MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) of selenium for Bacillus cereus were same and equal to 75mM. Absorption and secretion of nanoselenium was significantly higher than bulk Selenium (P

The aim of the present study was to develop an Antigen Capture ELISA (AC-ELISA) for the diagnosis of avian influenza virus infections. For this purpose, the nucleoprotein (NP) of the virus was captured by a monoclonal antibody (D'C4) and then detected using a rabbit polyclonal antibody. The developed AC-ELISA did not show cross-reaction with other viral and bacterial pathogens of poultry, while it was able to detect H9 serotype of avian influenza virus as well as H1 and H3 types of human influenza viruses. The sensitivity of this AC-ELISA for the detection of an H9 avian influenza virus strain H9N2 (A/Chicken/Iran/AH-1/06) was 10 times greater than a hemagglutination assay and was comparable with the sensitivity of the RT-PCR method. Furthermore, this method could recognize the influenza virus in tracheal swabs of experimentally infected chickens following 3-5 days post-infection. Based on the obtained results, it can be concluded that the developed AC-ELISA is able to detect H9, H1, and H3 influenza virus serotypes and is sufficiently sensitive and specific for the detection of infections caused by H9 serotype but, its applicability, sensitivity, and specificity for the detection of other serotypes of the virus remain to be determined. Key words: influenza virus A; nucleoprotein; monoclonal antibody; antigen capture ELISA RAZVOJ IN PREIZKUS NOVE METODE ELISA Z UJETJEM PROTITELES ZA ODKRIVANJE VIRUSA INFLUENCE A Namen raziskave je bil razvoj nove metode elisa z ujetjem protiteles za lažje diagnosticiranje okužbe z virusom ptičje influence. Nukleoprotein (NP) virusa smo najprej vezali z monoklonskimi protitelesi D’C4 in nato kompleks nukleoproteina in monoklonskega protitelesa označili s kunčjimi poliklonskimi protitelesi. Ta metoda ni kazala nobene navzkrižne (napačne) reakcije z drugimi virusi ali bakterijami ptičjega porekla, z njo pa smo lahko zaznali prisotnost virusa ptičje influence serotipa H9, pa tudi viruse človeške influence seroptipov H1 in H3. Občutljivost te metode za določanje linije H9N2 (A/Chicken/Iran/AH-1/106) virusa H9 je bila desetkrat višja v primerjavi z metodo hemaglutinacije in je bila primerljiva z občutljivostjo metode RT PCR. Z njo smo virus lahko določili v sapničnih izpirkih že 3 do 5 dni po okužbi poskusno okuženih piščancev. Iz pridobljenih rezultatov sklepamo, da nanovo razvita metoda elisa z ujetjem protiteles lahko zazna serotype H9, H1 in H3 virusa influence pri piščancih in ljudeh. Dokazali smo, da je metoda zanesljiva in zelo občutljiva za zaznavanje okužb s serotipom H9, uporabnost te nove metode za zaznavanje okužb z drugimi serotipi virusov influence pa bomo morali še dokazati. Ključne besede: influenca virus A; nulleoprotein; monoklonska protitelesa; elisa z ujetjem protiteles

Viral infections are the cause of great economic losses in the poultry industry. Development of appropriate reagents and serological diagnostic kits will help to control these infections. The aim of this study is to prepare a peroxidase labeled anti-chicken IgG using a MAb (5B8) against chicken IgG, for detection of chicken antibodies in ELISA. Hybridoma cells producing the MAb 5B8 were cultured in RPMI 1640 medium and the MAb was purified from the cells supernatant using a sepharose matrix column, sensitized with chicken IgG. The purified MAb was labeled with Horseradish peroxidase (HRP) by periodate treatment. The peroxidase labeled MAb was compared with a commercial polyclonal product for detection of chicken antibodies against avian influenza virus nucleoprotein in ELISA. Therefore, type A recombinant nucleoprotein influenza virus was used as the antigen and chicken sera prepared from healthy and influenza virus infected chickens were used as primary antibodies. The results showed that there is a strong and direct correlation (r =0.972) between the optical densities of a commercial anti-chicken IgG and the prepared conjugate. In conclusion, the conjugated MAb is appropriate for the development of serological diagnostic tests for poultry infections.

The aim of this study was to use petrochemical wastewater as the source of carbon for the production of polyhydroxyalkanoates (PHA) in an effort to decrease its cost of production. For this purpose, PHA producing bacteria were isolated from the petrochemical wastewater of Bandar Imam, Iran. The purified colonies were screened for PHA by Sudan Black B and Nile Blue A staining. Among positively stained bacteria, the best PHA producer was selected on the basis of cell growth, PHA content and the monomer composition of PHA. The phenotypic and genotypic identification this isolate showed it to be Bacillus axaraqunsis. The PHA was produced at a cell density of about 9.46 g/l of maximum concentration of 6.33g/l l, corresponding to 66% of cell dry weight. These results showed that B. axaraqunsis BIPC01 could be a potent PHA producer using wastewater for industrial purpose and simultaneously reducing the environmental pollution.

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.

This work aimed at improving the hydrolysis and fermentation processes of rice straw through different ammonia-based pretreatments to aid in bioethanol production. For this purpose, pretreatment was performed at 70 °C for 12 h, followed by enzymatic hydrolysis at 50 °C for 24 h and 72 h using 15 FPU cellulase and 30 CBU cellobiase. The best hydrolysis yield, based on the production yield and rate, for the 24-h digestion period was samples that had been soaked in methanolic aqueous ammonia (SMAA), with 72% of the theoretical maximum. However, for the 72-h digestion period, soaking in ethanolic aqueous ammonia (SEAA) was the best method, with 88% yield. In the case of ethanol production after 24 h, the SMAA pretreatment and SSF resulted in the highest yield at 72%. However, after 72 h of simultaneous saccharification and fermentation (SSF), SMAA-pretreated rice straw showed a yield of 85%, while the SEAA-pretreated sample resulted in a noteworthy yield of 89% of the theoretical maximum. However, with regard to the production yield and rate and pretreatment cost, the best method for ethanol production was judged to be the SMAA with 5% methanol, particularly after 24 h of SSF.

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.

Background Chlamydia trachomatis (C. trachomatis) is the most prevalent cause of bacterial sexually transmitted infections (STI) recognized throughout the world. The aim of this study is to determine different genotypes of genital C. trachomatis and the association between the serological markers of inflammation and genotypes of C. trachomatis in sexually active women (n=80) attending Shahid Beheshti Hospital in Isfahan, Iran. Materials and Methods In this descriptive study, endocervical swabs were collected from 80 women. There were 17 endocervical samples that showed positivity for C. trachomatis by plasmid polymerase chain reaction (PCR) using KL1 and KL2 primers. The omp1 gene was directly amplified in 17 plasmid PCR positive samples and was used to differentiate the clinical genotypes by omp1 gene PCR-restriction fragment length polymorphism (PCR-RFLP). The levels of IgG and IgA specific to C. trachmatis and C-reactive protein (CRP) were evaluated. Results Based on restriction-digestion patterns, four genotypes were identified. Genotypes E (35.3%) and F (35.3%) were the most prevalent, followed by D/Da (23.5%) and K (5.9%). There was no significant association between genotypes and the presence of IgG and CRP. Patients infected with genotype E showed a serological marker of chronic inflammation, i.e. IgA seropositivity, significantly more than patients infected with other genotypes (p=0.042). Conclusion Nested PCR could increase the sensitivity of omp1 amplification. Based on the presence of IgA, chronic C. trachomatis infections were observed more frequently among genotype E-infected patients in our population.

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

Nowadays, emergence and prevalence of MRSA (Methicillin Resistant Staphylococcus aureus) strain have become a great global concern in 21st century, so, it is necessary to discover new antibiotics against this pathogen. The aim of this study was isolation and evaluation marine bacteria from the Persian Gulf in order to finding antibiotic compounds against some pathogenic bacteria. For this purpose, water and sediment samples were collected from the Persian Gulf during March to October 2009. The antibacterial activity of the isolated bacteria was assessed using disc diffusion method. The Growth Curve Interference (GCI) parameter against MRSA was determined for the high potential antibiotic producing strain. The most important factors affecting fermentation conditions in antibiotic production were also optimized. Definite identification of intended isolate was confirmed by 16S rRNA sequencing. Altogether, 51 bacterial colony was isolated and among them only 3 bacterium showed antibacterial activity. Pseudoalteromonaspiscicida PG-01 isolated from a sediment sample was chosen as the best antibiotic producing strain. This strain was effective against all tested Gram-positive bacteria, had good anti-MRSA activity and also GCI value against MRSA was two times lower than MIC value. Among the optimized fermentation parameters, carbon and nitrogen sources play major role in efficacy of optimized antibiotic production. Ultrastructural study on the effect of intended antibiotic compounds on MRSA using TEM revealed that the target site for this compound is cell wall. Considering the antibacterial effect of PG-01 strain especially against MRSA, intended antibiotic compounds can gives hope for treatment of diseases caused by multi-drug resistant bacteria.