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In the present research, extracellular green synthesis of copper oxide nanoparticles was studied through a simple rapid and environmentally friendly approach using a new bacterial strain isolated from Hoz Sultan Qom lake (Bacillus cytotoxicus H2-7). In addition to the different synthesis methods, the factors influencing the production such as salt type, concentration, temperature, pH and shaker cycle on the production of copper oxide nanoparticles were investigated based on the amount of UV-vis absorption. CuSO4.H2O salt at a concentration of 5 mM as the best precursor salt, a stirring speed of 150 rpm at a physiological pH of 7 and an optimal temperature of 30 degrees Celsius resulted in the synthesis of copper oxide nanoparticles with maximum efficiency. After optimizing the growth conditions, the produced nanoparticles were characterized using different UV-Vis, FTIR, XRD, DLS and zeta potential techniques. The produced nanoparticles had absorption in the range of 250-300 nm. The average particle size was 50-80 nm with spherical morphology. Also, the antibacterial activity of copper oxide nanoparticles against E.coli ATCC11725 and S.aureus ATCC25923 bacteria was investigated by agar well and microdilution methods. The present study can be developed to develop a controlled and scalable process for bacteriosynthesis of nanoparticles that can be used for diverse applications in various industries. [ABSTRACT FROM AUTHOR]

Vegetation in cities is decreasing due to rapid urbanization and population growth. The development of vertical green infrastructure significantly helps to compensate for the lack of natural environment in urban areas. This research aimed to investigate the effect of different types of unconventional and bacterial strains on the growth and performance of some acclimate accumulator ornamental plants in the external green wall in two separate experiments and the form of split plots based on a randomized complete block design in 2022. The main factor of recycled water treatment included three levels (grey water, waste water of Kashfroud area and urban water (control)), and the subfactor of different bacterial strains in four levels (B1: Psedoumonas fluorescens + Azospirillum lipoferum + Thiobacillus thioparus+ Azotobacter chroococcum, B2:Paenibacillus polymyxa + Pseudomonas fildesensis + Bacillus subtilis+ Achromobacter xylosoxidans+ Bacillus licheniformis, B3: Pseudomonas putida+ Acidithiobacillus ferrooxidans+ Bacillus velezensis+ Bacillus subtilis+ Bacillus methylotrophicus+ Microbacterium testaceum and B0: Without the use of bacteria). Also, the investigated plant species included (Festuca ovina glauca, Ophiopogon japonicus). All functional traits showed significant differences at the 5% probability level. The highest number of flowers, the number of leaves, and the highest biomass and water use efficiency in Ophiopogon japonicus were observed in substrates inoculated with B3 compound and irrigated with wastewater. However, in the Festuca ovina glauca, the most functional traits mentioned were in the substrates inoculated with B1 compound and irrigated with gray water. Combining the substrates with combination B3 and B2 and irrigation with wastewater effectively adjusted the temperature and humidity of two lawns in all three seasons of the study. The results of this research suggest the integration of the substrates with the combination of bacteria and the use of recycled water in external green walls in dry climates for the sustainable future of contemporary cities to include green space. [ABSTRACT FROM AUTHOR]

Background and Objective: Due to the importance of managing medical sharps waste and the potential harm caused by these types of waste, the use of safe technologies that simultaneously encapsulate and reduce their volume is considered one of the essential needs for managing medical waste in hospitals and other healthcare facilities. The main objective of this study was to investigate the efficiency of disinfecting and encapsulating device for medical sharps waste. Materials and Methods: This device provides the process of containment and encapsulation of medical sharps waste by creating a stable protective foam without oxidation through inductive heat in a closed environment, preventing the dispersion and release of these wastes. Gas samples from the device's output were collected using the NIOSH 1501 method and analyzed using GC-MS. The performance efficiency of the device was evaluated based on the biological monitoring of the indicator bacterium Bacillus stearothermophilus. Results: The results showed that the average concentration of BTEX gases (benzene, toluene, ethylbenzene, and xylenes) and other volatile organic compounds in the device's output was within the permissible limit. The concentrations of Benzene, Toluene, Ethylbenzene and Xylene gases were 0.04, 0.033, 0.029, and 0.029 ppm, respectively. The results of biological monitoring showed that the reduction of the microbial load was 9999.99 (Log 6) and the decontamination process was acceptable. Additionally, this device has the advantage of reducing the volume of sharp and plastic objects during the encapsulation process, which can be further used in plastic pyrolysis/ recycling industries. Conclusion: It is hoped that by using this innovative and domestic device in the decontamination units of hospitals across the country, we can take an effective step towards improving medical waste management, reducing waste production, reducing hospital costs, and preserving and enhancing the country's health. [ABSTRACT FROM AUTHOR]

Wheat germ is a high -nutrient byproduct of wheat milling, however it has a short shelf life and extremely restricted ideal intake due to the intensive activities of lipase and lipoxygenase. In order to increase the storage life of probiotic wheat germ containing Bacillus badius, the freeze drying method was used in this study, and the effect of using xanthan gum: maltoxtrin in different ratios of 0.3:1, 0.1:1, and 0.03:1 as the capsule wall on antioxidant properties and physicochemical characteristics of probiotic wheat germ during 360 days of storage was investigated. Three control treatments were also produced without probiotic bacteria and had the same quantities of gums as the treatments. A pure wheat germ sample was also analyzed on the first day, 180 and 360, along with the encapsulated samples, for better comparisons and the influence of applied treatments. The experiments used a completely random design, and the treatments were analyzed using SPSS software and comparing the averages using Duncan's multi - range test at the 99% confidence level. The use of xanthan gum and maltodextrin as wall materials increased the antioxidant qualities in encapsulated wheat germ, according to the findings of this study. The introduction of Bacillus badius bacteria as a probiotic resulted in a substantial decrease in oxidation indices in wheat germ (P<0.01). In general, it can be stated that Bacillus badius bacteria, as a powerful probiotic, can extend the storage time of encapsulated wheat germ. Furthermore, xanthan gum is proposed as a good material for wheat germ encapsulation to enhance shelf life. [ABSTRACT FROM AUTHOR]

The aim of this study was to produce a new bioactive composite film using whey protein concentrate and jujube mucilage reinforced with postbiotics of Bacillus coagulans IBRC-M 10807. For this purpose, four films including whey protein concentrate film (WPC), whey protein concentrate film containing B. coagulans postbiotics (WPC+PBs), whey protein concentrate film and jujube mucilage (WPC+MUC), and whey protein concentrate film and jujube mucilage containing B. coagulans postbiotics (WPC+PBs+MUC) each in three replicates of production and their physicochemical, antimicrobial, antioxidant and mechanical, were compared in the form of a completely random design and with the analysis of variance method. The results showed that the addition of postbiotics and jujube mucilage caused a significant increase in the moisture and solubility of the films (P<0.05). Adding postbiotics causes an inhibitory effect against Staphylococcus aureus and Escherichia coli bacteria (P<0.05). The addition of postbiotics and jujube mucilage caused a significant decrease in the L index of the produced film samples (P<0.05). The results showed that the a and b indexes increased significantly with the addition of postbiotics and jujube mucilage (P<0.05). The results of the present study showed that the produced bioactive biocomposite film has the potential to be used in food packaging. [ABSTRACT FROM AUTHOR]

Background: and Aim Acinetobacter baumannii causes various nosocomial infections and has a high antibiotic resistance. Probiotics can produce metabolites with antimicrobial properties. This study aims to evaluate the antimicrobial ability of probiotics against nosocomial pathogens by inhibiting the ompA gene expression effective in biofilm formation in Acinetobacter baumannii. Methods & Materials: The antimicrobial properties of probiotics against nosocomial pathogens were evaluated phenotypically. The polymerase chain reaction (PCR) technique was used to identify the ompA gene in Acinetobacter baumannii. After treatment with Bacillus licheniformis supernatant, the ompA gene expression was compared before and after treatment with real-time PCR technique. Ethical Considerations This study was approved by the ethics committee of Islamic Azad University, Qom branch (Code: IR.IAU.QOM.REC.1398.004). Results: Among the study probiotics, Bacillus licheniformis supernatant had the best antimicrobial properties against nosocomial isolates of Acinetobacter baumannii A52, Acinetobacter baumannii ATCC19606, Kelebsiella pneumonia ATCC70063, and Pseudomonas aeruginosa PAO1. Bacillus licheniformis supernatant also significantly reduced the biofilm formation and ompA gene expression in Acinetobacter baumannii. Conclusion: Bacillus licheniformis can produce substances with antimicrobial and antibiofilm properties. It can be used for controlling the causative agents of nosocomial infections. [ABSTRACT FROM AUTHOR]

Introduction: Electronic wastes are the remnants of electronic devices buried in the soil without processing and contain toxic substances such as heavy metals. Lead is one of the heavy metals in many electronic goods that, if not properly processed, can cause toxicity in the soil and may harm living things in very low concentrations. Therefore, the aim of the present study was to investigate the biosorption of lead metal by Bacillus tropicus isolated from soils containing electronic wastes in Isfahan. Materials and Methods: In this cross-sectional study, sampling of contaminated soils in several areas of the Zainal Pass hills of Isfahan, which is the landfill of electronic wastes, was performed. After measuring the temperature, pH, TOC, and the amount of metals in the soil sample, lead-resistant bacteria were isolated. The growth rate of bacteria was evaluated at concentrations of 5 to 35 mM of lead. Then, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined. The morphology, antibiogram, and molecular identification of the bacteria were performed by colony-polymerase chain reaction method and bioabsorption of bacteria was evaluated by ICP-OES. Finally, XRD, SEM images, and EDS were evaluated to investigate the fabrication of lead nanoparticles. The raw data were analyzed by SPSS software, using an independent t-test. Results: Based on the findings of this study, the pH of the evaluated soil was 9.4, its temperature was 27.8 ° C, the TOC of the sample was 1.8%, and the amount of soil lead was measured at 658.4 ppm based on ICP-OES analysis. It was significantly higher than normal. The lead-resistant bacterial strain isolated to lead had 99/69% genetic affinity with Bacillus tropicus, which had a high biological removal potential (56.35%) of lead metal. The XRD, SEM, and EDS results showed the conversion of adsorbed lead metal to nanoparticles. Discussion and Conclusion: Considering that Bacillus tropicus showed high resistance and adsorption to lead metal, it can be a suitable option for the bio-removal of lead from electronic and other industrial wastes in the future after the removal of antibiotic resistance genes. [ABSTRACT FROM AUTHOR]

Background & Aims: Bacillus cereus is a Gram-positive, rod-shaped, facultative anaerobic, motile, beta-hemolytic, spore forming bacterium commonly The bacteria is commonly found in the environment, is often found in soil and vegetation, and can be present in foods. It can cause foodborne illness worldwide. B. cereus illness is related to many foods - beef, turkey, rice, beans, and vegetables. Specifically, the diarrheal illness is often related to meats, milk, vegetables, and fish. This product may be contaminated with many bacterial pathogens, including Bacillus cereus (4). There are several ways to store vegetables; one way is drying, which is important for several reasons: long-term storage, reducing the volume for the storage, and move products more easily and faster The emetic-type illness is most often associated with rice products, but it has also been associated with other types of starchy products such as potato, pasta, and cheese products (5). Some food-mixtures (sauces, puddings, soups, casseroles, pastries, and salads, have been associated with food-borne illness in general. There are two types of food-borne B. cereus illness. In the first, contaminated food (many types of food, often left at room temperature) makes its way to the small intestine where the toxin, in this case, a large-molecular-weight protein, is released. This can lead to diarrhea, cramps, and sometimes nausea. Usually, vomiting is not present in this form of illness (6, 7). Incubation for the first type is 6 to 15 hours. In the second type, affected food, most often starchy food, and classically, rice, contains a different type of toxin (cereulide, an ionophoric low)molecular-weight dodecadepsipeptide that is pH-stable and heat and protease-resistant). This toxin causes emetic-type B. cereus illness. The incubation period for this type is 30 minutes to 6 hours (9). Bacillus cereus is caused by the ingestion of food contaminated with either the enterotoxigenic B. cereus or with the emetic toxin. In non-gastrointestinal illness, reports of respiratory infections similar to respiratory anthrax have been attributed to B. cereus strains harboring B. anthracis toxin genes (10). The spore of this bacterium is resistant to severe environmental conditions including heat, freezing, drying, and radiation, and may be considered an infectious agent for this bacterium. Changes in diet and lifestyle in recent years and the growing trend of using ready-made products (4). In the gastrointestinal tract (small intestine), vegetative cells, ingested as viable cells or spores, produce and secrete a protein enterotoxin and induce a diarrheal syndrome, whereas emetic toxin, a plasmid-encoded cyclic peptide (cereulide), is produced in food products and ingested as a formed toxin. Dry vegetables it is suitable for the survival quickly multiply at room temperature (12). There are two main types of intestinal illnesses caused by B. cereus. One is diarrheal, and one leads more to nausea/vomiting. B. cereus has also been implicated in infections of the eye, respiratory tract, and in wounds. The pathogenicity of B. cereus, whether intestinal or nonintestinal, is intimately associated with the production of tissue-destructive exoenzymes. Among these secreted toxins are four hemolysins, three distinct phospholipases, an emesis-inducing toxin, and proteases. The specific name, cereus, meaning "waxy" in Latin, refers to the appearance of colonies grown on blood agar.Bacillus cereus is one of the most important causes of spore-bearing bacteria such as Bacillus (5, 7, 11). The aim of this study was to isolate and identify Bacillus cereus in bulk and packaged dried vegetables by culture and PCR. Methods: This is a cross-sectional descriptive study from February 2019 to October 2020. In total 160 samples (80 from each of open and packed dried vegetables) were evaluated for the contamination of Bacillus cereus. 25 g of the sample was poured into 225 ml of peptone water and incubated at 37 ° C for 24 hours and then one ml of 0.1 dilutions of the suspension was inoculated into on the specific medium of Bacillus cereus (Scharlau, Spain). (MYP Agar) Mannitol Egg Yolk Polymyxin Agar. For the total count, 10 g of each dried vegetable was added into 90 ml of 0.1% peptone water and then 1 ml of dilutions (10-1, 10-2, 10-3), were inoculated into MYP Agar medium and incubated at 37 ° C for 24 hours. Large pink colonies (no fermentation of mannitol) with a precipitated halo (due to lecithinase production) were considered suspicious colonies. The identification was carried out by catalase and biochemical tests. anaerobic conditions, growth at 45 ° C, lestinase C test, hemolysis B in blood agar with 5% sheep blood, MR-VP test, penicillin sensitivity 10 IU test,and nitrate reduction(13). For molecular analysis, the polymerase chain reaction for the internal transcribed spacer (ITS) gene was used to confirm Bacillus cereus. In order to extract DNA from a pure colony of bacteria, it was cultured in an LB medium and after incubation, the resulting culture was precipitated and the genome was extracted using phenol-chloroform. The quality and quantity of DNA extracted were evaluated by spectrophotometry and electrophoresis. The extracted DNA was frozen at -20 ° C for later use (14). The PCR program consisted of an initial temperature of 94 ° C for 5 min, then 35 cycles consisting of 94 ° C for 30 s, 52 ° for 30 s, and 72 ° for 30 s. PCR reaction was performed in Thermal Cycler (Primus 96, Peqlab Biotechnologie GmbH, Erlangen, Germany). The standard strain of 11778 Bacillus cereus was used as a positive control. The PCR product was electrophoresed in 1% agarose gel at a voltage of 100-80 volts and after staining with ethidium bromide 1 mg/ml was observed and photographed by a gel dock device. Initially, the PCR gradient for the gene was placed in the annealing temperature range of 50 to 60 degrees, which was finally selected at an optimum temperature of 52 degrees (15). Using SPS software, data were analyzed by chi-square test. p<0.05 was considered significant. Results: The B. cereus contamination were found in 21 (26.25%) and 13 (16.25%) of open and packed dried vegetable samples respectively. There was no statistically significant difference (p>0.05) between contamination rate of B. cereus in open and packed dried vegetable samples. Also, contamination rate of B. cereus was not significantly different (p>0.05) among various kinds of vegetable samples. The results of this study showed that 34 (21.25%) out of 160 samples of dried vegetables were infected with Bacillus cereus by the phenotypic method. PCR results of the ITS gene showed that all 34 strains isolated by culture were also identified by molecular method. In total 7 (4.37%) dill, 5 (3.12%) tarragon, 5 (3.12%) parsley, 5 (3.12%) mint, 6 (3.75%) soup, 4 (2.5%) coriander and 2 (1.25%) turmeric were identified as Bacillus cereus respectively. Conclusion: Our study showed that despite the supply of packaged dried vegetables, there is still the possibility of microbial contamination, especially by anaerobic bacteria. Although the rate of contamination of dried vegetables in open packaged (13.2%) was more than dried packaged (12.8%).This percentage of contamination probably indicates a lack of hygiene in the drying process in both traditional and industrial forms. [ABSTRACT FROM AUTHOR]

Introduction: Surface display technology enables the binding of proteins and peptides to the surface of living cells, including mammalian cells, yeast, bacteria, and spores. Among the various systems used for surface display, Bacillus subtilis spores have advantages such as resistance to adverse environmental conditions such as heat, radiation and chemicals, safety for humans and no need for the heterologous protein to pass the membranes for binding to spores. Materials and Methods: This study is a review that investigates the structure of the Bacillus subtilis spore, spore surface display, and its application in the development of mucosal vaccines and adjuvants. Ethical considerations: All Ethical principles in writing this article have been observed according to the instructions of the National Ethics Committee and the COPE regulations. Results: Heterologous proteins can be displayed genetically and non-genetically on the spore surface. The surface display is a promising strategy for the development of whole-cell factories with many industrial and biotechnological applications, leading to significant advances in the production of biocatalysts, the development of live vaccines, bio-adsorbents and sensors, epitope mapping, inhibitor design, and protein/peptide library screening. Conclusion: It is hoped that oral vaccines of Bacillus subtilis spores will be of significant help in the prevention and treatment of diseases including COVID-19 in the future. [ABSTRACT FROM AUTHOR]

Auxin produced by plant growth-promoting bacteria (PGPR) in the wheat rhizosphere, can improve plant yield under water deficit stress condition. To investigate this issue, a completely randomized factorial design with three replications was conducted under greenhouse condition at the University of Maragheh, Eastern-Azarbayjan, Iran during 2019. Treatments were two types of growth-promoting bacteria (Bacillus simplex 40, Bacillus simplex 52); two moisture levels (50% and 80% of water holding capacity in perlite) and two levels of tryptophan (0 mg L-1 and 100 mg L-1). Under the condition of 50% of water holding capacity, the application of tryptophan without bacterial inoculation decreased wheat dry matter yield by 5%. Inoculation of Bacillus simplex 40 in the absence of tryptophan led to 25% increase in wheat dry matter yield while application of tryptophan reduced the trait by 17%. Under the stress condition, catalase enzyme activity increased by 33% and guaiacol peroxidase activity increased by 2.3% in inoculation treatments compared to control treatments. In conclusion, bacterial inoculation was able to increase wheat dry matter yield by improving the wheat antioxidant system under drought-induced oxidative stress. Furthermore, the decrease in wheat dry matter in the presence of tryptophan treatment may be attributed to probable hormonal disorders in wheat caused by high concentration of applied tryptophan. [ABSTRACT FROM AUTHOR]

Introduction: Medicinal plants are valuable sources of different antioxidant and antimicrobial compounds. In this study, the effects of different extraction methods with aqueous and methanolic solvents were investigated on the antioxidant and antimicrobial activities of Teucrium hyrcanicum L. Material & Methods: In this basic experimental study, aqueous and methanolic extraction was carried out using three methods, including a magnetic stirrer, a Bain-Marie bath, and Shaker. The antioxidant effects were then determined using DPPH and RP methods along with the determination of total phenol and total flavonoid. The antibacterial effect of aqueous and methanolic extracts against Staphylococcus aureus, Bacillus cereus, and Escherichia coli was determined through the disk diffusion method. (Ethic code: IR.ausmt.rec.1398.11.34) Findings: The evaluation of antioxidant properties showed that methanolic extract had a stronger effect than aqueous extract. Moreover, it was demonstrated that the magnetic stirrer method was superior to the other two extraction methods. The same results were obtained for total phenol and total flavonoid as well. Evaluation of antibacterial properties revealed that methanolic extract had antibacterial activity, while aqueous extract did not show antibacterial activity. Discussion & Conclusion: The results of this study showed that Teucrium hyrcanicum L. was more effectively extracted through the magnetic stirrer method than other extraction methods. Both aqueous and methanolic extracts had antioxidant properties, while only methanol extracts showed antibacterial properties. Therefore, this plant can have good therapeutic application in the treatment of diseases due to its antioxidant properties. [ABSTRACT FROM AUTHOR]

Background and Objective: With increasing population growth and water pollution, fresh water supply sources are declining and can not meet today's human needs. Thus, energy conversion systems with high efficiency and low pollution such as desalination microbial cell have been considered. Therefore the aim of this research was to investigation the efficiency of microbial desalination cell (MDC) for desalination and treatment of salt wastewater. Materials and Methods: To address this issue, the decision was taken to use saline synthetic wastewater with different initial salt concentrations (2, 5, 7 and 10 g/L NaCl) and, different hydraulic retention times (1, 2, 3 and 72 h) in open circuit voltage (OCV) and zlosed circuit voltage (CCV) continuous mode. Results: The results showed that highest EC removal was 11.2% and 14.3% with 10 g/L NaCl in open and closed circuit mode, respectively. Maximum COD removal of 68.7% was achieved in CCV mode that was obtained at 10 g/L NaCl. Additionally, Escherichia coli, Bacillus, Enterobacter, Staphylococcus aureus, Pseudomonas and Citrobacter were diagnose as effective bacteria in decomposing wastewater. Conclusion: The obtained results proved that MDC desalination microbial cell technology is Emerging technology that has many unknown aspects; however, it is expected to be an appropriate technique for wastewater treatment and desalination. [ABSTRACT FROM AUTHOR]

Background and Aim The assessment of indoor air quality and detection of its microbial pollutants in classrooms is very important because of the presence of children sensitive to these pollutants. The aim of this study was to determine the concentration and characterization of dominant species of biological aerosols and their relationship with environmental factors in two selected primary schools in Arak, Iran. Methods & Materials This cross-sectional study was conducted at two primary schools in Arak, Iran in Fall 2018. Indoor air sampling was performed using single-stage Andersen microbial sampler (at flow rate of 28.3 liters/min) containing bacterial and fungal culture media. The effects of suspended Particulate Matter (PM) and environmental parameters (temperature and humidity) on the density of bioaerosols were evaluated. Ethical Considerations This study with an ethics code of IR.ARAKMU.REC.1397.76 was approved by the Research Ethics Committee at Arak University of Medical Sciences. Results The overall mean density of indoor bacteria and fungi was 448 cfu/m3 and 394 cfu/m3, while the mean density of outdoor bacteria and fungi was 210 cfu/m3 and 127 cfu/m3, respectively. There was a positive correlation between indoor density of airborne bacteria and suspected PM concentrations (PM 10 and PM 2.5), and between PM2.5 concentration and indoor fungal density (P<0.05). Penicillium (40%), Cladosporium (19%) and Aspergillus (16%) were dominant species of fungi, while Staphylococcus (42%), Micrococcus (28%), Bacillus (21%) were the dominant species of bacteria. Conclusion The age and type of building and the density of students in a classroom are the main factors in increasing the concentration of bioaerosols. [ABSTRACT FROM AUTHOR]

Background: Bacteria are one of the important sources of producing enzymes. The aim of this study was to the isolate the halophilic bacteria producing amylase, lipase and pectinase from saline soil of the center of Iran. Methods: In this study, soil samples were collected from Dagh Biarjmand and Haj Aligholi in Semnan province. At first, isolated halophilic bacteria were cultured and screened for producing of hydrolytic enzymes including amylase, lipase and pectinase using enzyme-specific media. The enzymatic activities of isolates were recognized by induction of growth inhibition zone and/or precipitation around colonies after addition of related indicators. Afterward, enzyme positive isolates were identifies using the 16S rRNA sequencing. Results: Out of 7 bacterial isolates, 4 bacteria with amylase activity, 6 bacteria with lipase activity and 3 bacteria with pectinase activity were recognized and identified. Results showed that 2 isolates with the ability of producing all three types of enzymes belong to Bacillus genus using molecular identification methods. Furthermore, the halophilic bacteria producing amylase and pectinase were belonging to Bacillus and Halobacillus genera. Besides, bacteria producing lipase belonged to Bacillus and Virgibacillus genera. Conclusion: The Bacillus bacteria isolated from the soil can produce all three amylase, pectinase and lipase enzymes. [ABSTRACT FROM AUTHOR]

Nowadays, the consumers are extremely concerned about using chemical preservatives in foods and tend to use safe natural food products with healthful benefits. Pomegranate can have such a role. In this study, the antimicrobial properties of the extracts (peel, juice and nucleus) such as organic, aqueous and anthocyanin extracts extracted from different parts of pomegranate were examined and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) on Staphylococcus aureus, Escherichia coli, Bacillus cerous and Salmonella tiphy were determined using liquid dilution susceptibility test. According to results, the most inhibitory effect was related to peel extractions. Minimum inhibitory concentration (MIC) was related to organic extractions and Anthocyanin of peels which were effective in concentration of 62.5 ppm on Staphylococcus aureus and Escherichia coli and had inhibitory effect on Bacillus cereus and Salmonella tiphy and also, organic & Anthocyanin extractions of peel had bactericidal effect in concentration of 125 ppm on Staphylococcus aureus and Escherichia coli and in concentration of 250 ppm on Bacillus cereus and Salmonella. After, peel extractions, the most antimicrobial was dependent on pomegranate juice extractions which aqueous, organic and Anthocyanin extractions in concentration of 250 ppm had inhibitory effect on Staphylococcus aureus and Escherichia coli bacteria and in concentration of 500 ppm had bactericidal effect on bacteria. Also, on Bacillus cereus and Salmonella tiphy bacteria in concentration of 500 ppm had inhibitory effect and in concentration of 1000 ppm had bactericidal effect, of course except aqueous extractions of pomegranate juice which showed inhibitory and bactericidal effects respectively in concentrations 250 and 500 ppm on Bacillus cereus bacterium. It can be mentioned that peel and pomegranate juice extractions have high antibacterial effects for high phenolic compounds and high antioxidant activity and it is concluded that phenolic compounds and antioxidant activity approximately have direct proportion with antimicrobial activity. [ABSTRACT FROM AUTHOR]

Background and Aims: Increasing drug resistance to antibiotics in most bacteria has led to the development of natural antimicrobial compounds. Peppermint (Mentha piperita L.) is one of the most widely used herbs that has many therapeutic effects. The purpose of this study is the evaluation of antimicrobial and antioxidant activity of essential oil of Mentha piperita L. Materials and Methods: : In this study, after collecting and drying the leaves, essential oils of the plant was extracted using a solvent-free microwave extraction. The compounds of essential oil were identified by the GC-MS (Gas chromatography-mass spectrometry). The effect of antioxidant was determined by beta-carotene test and antimicrobial activity was carried using agar-dilution method also, the minimum inhibitory concentration (MIC) value was evaluated. Results & Discussion: Menthofuran, Menthol, and 1S-Neomenthyl acetate were the major compounds of essential oil of Mentha piperita L. collected from Marivan, respectively; menthol is the main compound of essential oil. The essential oil was more effective on gram-positive bacteria (Staphylococcus epidermidis, Bacillus subtilis, Staphylococcus aureus) and gram negative (Shigella dysenteriae, Klebsiella pneumonia) also had a good antioxidant activity compared to the standard BHT (butylated hydroxytoluene).Due to its relatively good antimicrobial and antioxidant properties, it can be used in the pharmaceutical and food industries. [ABSTRACT FROM AUTHOR]

Introduction: Most cases of blood transfusion-associated bacterial sepsis are caused by platelet concentrates (PCs). Screening of PCs is carried out in the Iranian quality control plans as it is essential for detection of bacterial contamination. With regard to quality control, this study investigated the frequency of bacterial contamination of PCs through Gram staining and microbial culture methods. Materials and Methods: In this descriptive cross-sectional study, 880 cords out of 440 platelet product bags (two cords per platelet bag) were selected on the first and third days and included in the study. Direct smears were prepared from the samples for Gram staining, then they were cultured in blood agar and chocolate agar under aerobic and microaerophilic conditions for detection of both Gram positive and negative cocci and Gram positive bacteria. Cultures were also made in MacConkey medium under aerobic conditions to identify Gram negative bacilli. In cases of bacterial growth and colony formation, differential tests were performed to detect the bacteria. Results: One case of Staphylococcus saprophyticus was isolated of 440 platelet bags collected from donors in Jahrom Blood Transfusion Organization, from which two platelet cord (880 samples) had been isolated on the first and third days. Accordingly, a contamination frequency of 0.23% was detected for platelet products in Jahrom city. Conclusion: Performing staining and bacterial culture from all of the platelet cords before they are used is a good way to ensure safety and prevent bacterial contamination from platelet products and quality control. [ABSTRACT FROM AUTHOR]

Background and Aims: High prevalence of Methicillin Resistant Staphylococcus Aureus isolates (MRSA) as well as the multi-drug resistance in this bacterium causes difficulties in the treatment of infections due to these bacteria. Hence, detection of MRSA isolates by rapid and accurate methods is necessary. PCR-ELISA is an accurate and molecular technique that is used for the detection of several pathogens. The aim of this study is the detection of MRSA using PCRELISA. Materials and Methods: Specific primers for mecA gene were designed. Then, dNTP labeled with Digoxigenin was applied for amplifying mecA gene. DIG-labeled PCR products were seeded on the well coated streptoavidin and identified by anti-DIG-peroxidase conjugate. Furthermore, Biotin-labeled DNA probe specific for mecA gene was used. Sensitivity and specificity of the method was determined. Resistance to methicillin among 70 clinical isolates was determined by the disk diffusion, agar dilution and PCR-ELISA methods. Results: MecA gene of S. aureus was amplified using gene specific primers resulted in a fragment with 310 bp length. Findings from the PCR-ELISA technic showed no cross-reactivity with Klebsiella Pneumoniae, Bacillus subtilis and Esheriashia coli as control bacteria and its sensitivity was 0.5 ng. The prevalence of MRSA clinical isolates by the disk diffusion, agar dilution and PCR-ELISA methods was 60%, 58.5% and 60%, respectively. Conclusion:The PCR-ELISA technique was known as an accurate and rapid test for the detection of infection agents using their specific gene. This technic can applied as an appropriate alternative method for time-consuming, less sensitive and expensive techniques such as Real-time PCR and differential biochemical tests which are currently used in laboratory. [ABSTRACT FROM AUTHOR]

Introduction: Incidence of drug resistance against chemical antimicrobial drugs has led the use of medicinal plants for treatment of infections in recent years. The aim of this study was to examine possible antibacterial and antifungal effects of Methanolic, Ethanolic and Aqueous extracts of Ocimum basilicum plant in vitro. Materials & Methods: After preparing the extracts with maceration method, antimicrobial activities and Minimum inhibitory concentration were examined by Disk-Diffusion, serial dilution method against bacteria (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa) and fungi (Aspergillus niger and Candida albicans). To standardize of study, we used anti biogram disks and ATCC bacteria. Results: The results showed that the methanolic extract of Ocimum basilicum had maximum antimicrobial activity against Staphylococcus aureus and Aspergillus niger with the diameter of inhibition zone (20±1.02 and 18±1.20mm) respectively. In addition, the minimum inhibitory concentration of Methanolic extract against Staphylococcus aureus and Aspergillus niger was documented in 12.50 and 25 mg/mL, respectively. The aqueous extract of the Ocimum basilicum did not have a good effect compared to methanolic and ethanolic extracts. Conclusions: Based on the results of this study, it was found that methanolic extracts of Ocimum basilicum compared to aqueous and ethanolic extracts have antibacterial activity against gram-positive bacterial strains of Staphylococcus aureus and Bacillus subtilis. It also shows favorable antifungal properties against Aspergillus niger fungi. [ABSTRACT FROM AUTHOR]

Background: The spread of drug-resistant microbial strains has been known as one of the main problems of world health in the last century. In addition, indiscriminate and arbitrary use of antibiotics is resulted to appear the side effects such as gastrointestinal discomfort, nausea, diarrhea and allergy. These factors have encouraged researchers to identify and use the novel antibacterial agents containing more powerful and broad-spectrum inhibitory effects, and fewer side effects. Thiazole, thiazolidine, imidazole, tetrahydropyrimidine, oxazolidine and thiazepine derivatives are the parts of the most important families of heterocyclic compounds that their various biological properties have been reported. In this study, the antibacterial effects of 30 new derivatives of these families have been investigated against the bacteria including Staphylococcus epidermidis, Streptococcus pyogenes, Bacillus thuringiensis, Salmonella typhi and Shigella flexneri. Methods: After preparation of solution of derivatives in DMSO, in order to evaluate their antibacterial effects, inhibition zone diameters were measured via a disk diffusion method. Besides, the broth microdilution method was also used to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). All effects have been compared to the antibiotics gentamicin and penicillin. Results: Inhibitory effects were observed only in some derivatives. Thiazole derivative 23 as the most effective compound had an inhibitory effect against all tested bacteria. Even though, imidazole derivative 3 had no inhibitory effect against Salmonella typhi, its effects against five bacterial strains were obviously identified more as well. Conclusion: Inhibitory effects of various new heterocyclic derivatives against some standard bacterial strains were proved. In order to use these derivatives as antibiotic, their inhibitory effects should be evaluated on drugresistant strains of these pathogens in the next step. [ABSTRACT FROM AUTHOR]

Introduction: Silver nanoparticles have a wide range of applications in medical sciences, which are size-dependent. Synthesis of silver nanoparticles is valuable due to their numerous applications in detection of pathogens, cancer therapy and targeted drug delivery. The purpose of this research was to produce silver nanoparticles by the extract of aerial parts of Ferulago angulata and to check antimicrobial activity of nanoparticles. Materials and Methods: To this end, the extract of Ferulago angulata was exposed to silver nitrate solution of 0.1 molar at different concentrations (2.5, 5, 7.5, 10 and 15 mM) for 24, 48, 72 and 96 hours. After the color changed to brown, the present of silver nanoparticles was confirmed using UV-visible, DLS, SEM, TEM, XRD and FTIR analyses. Results: The UV-visible spectroscopy showed that silver nanoparticles had an absorption peak at 450 nm. The particles had a mean diameter of 19 nm, a size of 3 to 62 nm, and spherical shape. Finally, the antimicrobial activity of silver nanoparticles was investigated and confirmed against the Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. Conclusion: The results show this plant has a good functioning for the synthesis of silver nanoparticles. Therefore, it can be used for treating many diseases transmitted by bacteria. [ABSTRACT FROM AUTHOR]

Background: Today, discovery and production of new antimicrobial drugs has been emphasized due to the growing of antimicrobial resistance. The purpose of this study was to screen out antimicrobial producing bacteria among halophilic or halotolerant Gram-positive endospore-forming bacteria isolated from different areas of Iran. Materials and Methods: 62 strains were isolated from salin lakes of Iran, endospore-forming ability was evaluated and further identification of strains was done using 16S rRNA gene sequencing. Screening test was performed using two-layer agar diffusion method in which the indicator strains, Bacillus cereus (ATCC 14579) and Escherichia coli, (PTCC 1330) were inoculated in the seed layer. Finally, the production of antimicrobial active agent during a period of 7 days was studied followed by evaluating the effect of base-layer agar concentration on the dissemination of antibacterial metabolite. Results: Isolates WT6, R4A19 produced an agent(s) which inhibited the growth of both B.cereuse and E.Coli. The inhibition zone against only E.Coli was observed when R4A20 strain had been cultured in the base layer, while four non-bacillus strains (R4S2, LbS2, RF1 and WT19) could inhibit the growth of B.cereuse. The antibacterial compound production of WT6 against Bacillus cereuse and E.Coli reached to its optimumm leved after 3 and 4 days respectively, while R4A20 produced the active substance, optimally, after 5 days. No significant difference effect on diameter of zone inhibition was observed among various base-layer agar concentrations. Conclusion: Halophile or halotolerant endospore-forming bacteria isolated from different areas of Iran possess a potential to be considered as interesting microorganisms for further antimicrobial research studies. [ABSTRACT FROM AUTHOR]

Background and Aims: The use of microorganisms in the synthesis of metal nanoparticles is known as an eco-friendly method. Moreover, because of the ability of microorganisms to synthesize nanoparticles of various sizes, shapes and morphologies, this method has gained extreme attentions in recent years. The aim of this study was, therefore, to investigate the antimicrobial effects of silver nanoparticles synthesized by bacteria isolated from agricultural soils of Kerman, Iran. Materials and Methods: This study was carried out in 2014. Silver nanoparticles were characterized by SEM, EDS and XRD analyzes. The antimicrobial effects of silver nanoparticles were also assessed against some pathogenic bacteria. Results: Of the 40 silver nanoparticle producing bacteria, the strains that were able to produce silver nanoparticles with high antimicrobial activity yielded under different environmental conditions, were selected. The results of scanning electron microscopy (SEM) confirmed the presence of silver nanoparticles with a spherical shape. EDS analysis showed that silver content of the particles was about 60 wt %. Sequence alignment and phylogenetic tree results showed that M9 and B7 strains are closely related to Bacillus cereus and Pseudomonas argentinensis, respectively, with 99% homology. Conclusions: The results showed that the M9 and B7 strains can synthesize silver nanoparticles with high antimicrobial effects under different environmental conditions. [ABSTRACT FROM AUTHOR]

Background and Aims: One of the most important factors in food industry is the formation of microbial biofilm which can be the potential source of food products contamination with food spoilage and foodborne pathogenic bacteria. This study was conducted to evaluate the inhibitory effects of zinc oxide nanoparticles on biofilm formation of some foodborne bacterial pathogens. Materials and Methods: This research was carried out in 2015. Minimum inhibitory concentration (MIC) of zinc oxide nanoparticles for E. coli (ATCC 35218), Staphylococcus aureus (ATCC 6538), Salmonella typhimurium (ATCC 14028) and Bacillus cereus (ATCC 14579) was determined by using 96-well microplate and resazurin reduction method. Biofilm formation inhibition was assessed with microtiter plate method based on crystal violet staining and measurement of optical density using microplate reader. Results: MIC of zinc oxide nanoparticles for the above mentioned bacteria was respectively 1, ≤ 0.5, 1 and 2 mg/mL. The inhibition percentages of biofilm formation at the MIC of the nanoparticles were 90.20, 85.69, 83.65 and 61.96, respectively. Conclusions: In this study, zinc oxide nanoparticle showed the ability to inhibit the formation of biofilm even in sub inhibitory concentrations or Sub-MICs. No significant difference (P>0.05) was observed in the biofilm inhibitory effects of ZnO nanoparticles at MIC and ½MIC between E. coli and S. aureus. Results of this study showed the inhibitory effects of zinc oxide nanoparticles on biofilm formation of the studied foodborne bacterial pathogens. According to the importance of these bacteria in public health, ZnO nanoparticle can be used as a cleaning agent for the surfaces, apparatus and production lines in food plants in order to prevent foodborne bacterial biofilm formation. [ABSTRACT FROM AUTHOR]

Background and Aims: Lactic acid bacteria play an important role in production and storage of fermented foods. This study aimed to evaluate the antimicrobial properties of a dominant lactic acid bacteria isolated from barley sourdough against some of foodborne indicator bacteria. Materials and Methods: In this experimental study which was conducted in 2015-2016 at Gorgan University of Agricultural Sciences and Natural Resources, after molecular identification of dominant lactic acid bacteria isolated from whole barley sourdough, antimicrobial effect of the isolate and it's cell free culture filtrate as native and neutralized cell free culture filtrate obtained from logarithmic and stationary phases were investigated based on disc diffusion and microdilution (antibacterial effect) and overlay and agar spore spot (antifungal effect) methods. Results were also compared by the one way analysis of variance. Results: Sequencing results of PCR products lead to identification of Weissella cibaria as a dominant lactic acid bacteria isolated from whole barley sourdough. Based on the results of investigating of the antibacterial effect the highest antagonistic effect of the isolate and it's native cell free culture filtrate obtained from logarithmic phase were observed against Bacillus subtilis that was significantly (P<0.05) more than the other indicator bacteria. Furthermore, W. cibaria and it's cell free culture filtrate had proper antifungal effects on Aspergillus flavus and Aspergillus niger. Conclusions: Based on the results of this study, it is possible to use W. cibaria and it's cell free culture filtrate as biopreservative for controlling some microbial indicators in food and medical industries. [ABSTRACT FROM AUTHOR]

Background: Prevalence extension of antibiotic resistant bacteria has raised concerns about control of infections especially nosocomial infections. Many attempts have been done to replace antibiotics or limit their use. The use of antimicrobial agents produced by bacteria as antibiotic replacement has been promising in recent years. The goal of this study was to isolate Bacillus strains and evaluate their antimicrobial activity against some standard pathogens and clinical antibiotic resistant strains. Materials and Methods: In the present study, Bacillus strains were isolated from various resources and identified by 16S rDNA PCR method. Then, the phylogenetic tree of the isolates was constructed and antimicrobial activity of the isolates was investigated against some standard pathogens and clinical antibiotic resistant strains using spotting and well diffusion methods. Results: Eight Bacillus strains were isolated from 15 different samples. Based on the molecular identification, the isolates were identified as B.pumilus, B.coagulans, B.licheniformis, B.endophitycus and B.amiloliquefaciens. The results showed that isolates have antimicrobial activity against meticilin-resistant Staphylococcus aureus, vancomycin resistant enterococci, Klebsiella, Acinetobacter, Salmonella, Shigella, Listeria, Streptococcus and Escherichia coli. Conclusion: In this study, isolated Bacillus strains produced antimicrobial agents against pathogens and antibiotic resistant strains and inhibited their growth. [ABSTRACT FROM AUTHOR]

Background: As lactobacilli possess an antagonistic growth property, therefore they may be used as bioprotective agents for infection control. The aim of this study was to investigate the antagonistic effect of lactobacilli isolated from local dairy. Materials and Methods: In this study 26 species of Lactobacilli were isolated from milk, homemade yoghurt and cheese. Each isolated bacteria was tested for its tolerance to acidic environments at pH (2.0, 3.0, and 4.0) and bile salt concentrations (0.3, 0.5 and 1% w/v). Also, isolates were further tested for their antimicrobial activity against common pathogenic bacteria such as Enterococcus feacalis, Listeria monocytogenes, Staphylococcus aureus PTCC 1112, Escherichia coli PTCC 1330 and Bacillus cereus PTCC 1015 by using the agar well method. Then the strains that are not only resistant to acidic conditions and bile salts but also have antimicrobial activity, were identified by 16S rRNA gene sequencing. Results: In this study, most of isolated Lactobacilli were found to inhibit growth of pathogens (96.15%). 61.5% and 84.62% of isolated lactobacilli tolerated to pH 2 and 0.3% bile salt. Only two strains, 53C and 22CL, were more resistant to pH 2 and high concentration of bile salt. The Phylogenetic analysis based on 16S rRNA sequencing revealed that two strains (53C and 22CL) belong to species of Lactobacillus casei. Conclusions: According the results the two isolated resistant strains can be employed as probiotic starter in probiotic dairy products preparation. [ABSTRACT FROM AUTHOR]

Background and Aim: Marine microorganisms have an astonishing potential for producing antimicrobial substances against pathogenic bacteria. In this study, isolation and measurement of antimicrobial activity among these microorganisms against some pathogenic bacteria was carried out. Materials and methods: Samples were collected in autumn from the west of the Caspian Sea. Isolated samples were purified and antimicrobial activity among these samples against some pathogenic bacteria were measured by the use of two methods. At the end, genetic substance (DNA) of the strains with antimicrobial effect against pathogenic bacteria was extracted and polymerase chain reaction with universal primers was carried out. Isolated strains were identified by molecular method (16SrDNA PCR sequencing) and the strains were submitted and registered as new marine strains in the NCBI. Results: Results showed, the strains with antimicrobial activity had a noticeable effect on gram positive bacteria. So that gram positive bacteria were nearly inhibited in all cases but antimicrobial activity was restricted against gram negative bacteria, because gram negative bacteria were inhibited only in few cases. Finally, identification of stains with antimicrobial effect showed, the strains belong to Bacillus genus. Conclusion: According to this result; we can use marine bacteria for controlling growth of pathogenic bacteria that are resistant to drugs and as a big threat for the human health. Also we can optimize conditions for producing antimicrobial substances among them and we can extract them in industrial conditions for increasing quality and quantity antimicrobial substances in these bacteria for the use in different industries such as pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Background and Objectives: Microorganisms are known as an important biocatalysts for green chemistry which can be used beneficially for production of medically and pharmaceutically important compounds such as the bromine and paraxanthine through caffeine biotransformation. The aim of this study was to determine the bacterial subtypes which are able to use as a new biocatalyst for the synthesis of high-value added dimethylxanthines from caffeine as low-cost substrate. Material and Methods: In this experimental study, twenty-one bacterial strains isolated according to their ability to degrade caffeine using enrichment technique. Primary screening was performed by Thin Layer Chromatography (TLC). The selected strain characterized based on phenotypic analysis and also amplification of 16S rDNA gene. Biotransformation mixtures were quantified for produced methylxanthines by High Performance Liquid Chromatography (HPLC) technique. Results: Among the 21caffeine-degrading bacterial cultures, the resting cells of B. subtilis strain CTB04 are reported to be able to convert caffeine into the bromine and paraxanthine. The results showed that the strain CTB04 was capable of converting 2.5 g/l of caffeine to 1.35 g/l paraxanthine with molar yield (58.2%) and 0.66 g/l of the bromine with a 28.4% molar yield after 96 h biotransformation. Conclusion: There was a dual approach for bioremediation of the toxic caffeine from environment and a way for the production of pharmaceutically dimethylxanthines such as the bromine and paraxanthine as well. [ABSTRACT FROM AUTHOR]

Background: Today with raised use of antibiotics and prevalence of resistant strains, there is need for antimicrobial drugs that have fewer side effects than antibiotics. Rosmarinus officinalis is a medicinal plant which had many uses in traditional medicine. In this study, methanol leave extract of this plant is tested on various pathogens. Materials and Methods: In this in vitro study Rosmarinus officinalis was used to evaluate its antimicrobial effects. Methanol leave extract of this plant with concentrations of 400, 200, 100, and 50 mg/ml were prepared, and antibacterial activities were evaluated by well diffusion method on strains of Escherichia coli, Pseudomonas aeruginosa, Bacillus cereus and Staphylococcus aureus. Minimum inhibitory concentration and minimum bactericidal concentration were determined by the microplate method. Results: In this study, the most efficacy of thanol extract of rosemary leaves was at concentration of 400 mg/ml against Pseudomonas aeruginosa and Escherichia coli. Minimum inhibitory concentration of the extract on the growth of these bacteria showed changes from 6/25 mg/ml to 100 mg/ml. Also MBC of extract showed range from 12/5 to 200 mg/ml respectively. Conclusion: It was found that rosemary methanol extract inhibited growth of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa but did not inhibit of Bacillus cereus growth. [ABSTRACT FROM AUTHOR]

Background and Objectives: Salmonella typhi, Bacillus anthracis, and Yersinia pestis are potent human pathogenic bacteria that cause typhoid fever, anthrax, and plague,respectively. The classic microbiological methods for detection and identification of these agents are laborious and time consuming.Therefore, developing an accurate method for rapid detection of these potent human pathogens is important, especially due to their potential use as Bioterrorism agents. We have designed a new rapid molecular detection method by using multiplex PCR in a single reaction. Materials and Methods: PCR was carried out using specific primers for the virulence factor of S. typhi, hp and invA, B. anthracis virulence factors, chr and pa, and Y. pestis toxin, pla. The primer sets were tested for cross reactivity with individual DNA strains and mixtures in a multiplex PCR format. For determination of sensitivity of the method, we used colony counting and genomic DNA dilution. Results: Theresult with standard strains revealed that primers are specific for each strain as they have successfully amplified the desire products. The sensitivity analysis showed a 1-10 CFU and 1-10 copies of the genomes. In this respect, the accuracy of the result was checked by sequencing of the 1083-bp PCR products, except for anthrax, which was determined by enzymatic digestion. Conclusion: We have found a rapid, specific, sensitive, and a non-expensive molecular method for detection of three potent human pathogens. This finding provide an efficient diagnostic tool to determine these bacteria in bioterrorism samples. [ABSTRACT FROM AUTHOR]