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Objective: Multipotent cells derived from human exfoliated deciduous teeth (SHED) possess the ability to differentiateinto various cell types, including osteoblasts. This study aims to simulate the growth induction and osteogenicdifferentiation of SHED cells using probiotics and their resultant biomaterials.Materials and Methods: This experimental study proceeded in two stages. Initially, we evaluated the effect ofautoclaved nutrient agar (NA) grown probiotic Bacillus coagulans (B. coagulans) on the SHED and MG-63 cell lines.Subsequently, probiotics grown on the Pikovskaya plus urea (PVKU) medium and their synthesised hydroxyapatite (HA)were identified using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), andFourier transform infrared spectroscopy (FTIR), and then used to stimulate growth and osteogenic differentiation of theSHED cell line. Osteoblast cell differentiation was assessed by morphological changes, the alkaline phosphatase (ALP)assay, and alizarin red staining.Results: There was a substantial increase in SHED cell growth of about 14 and 33% due to probiotics grown on NAand PVKU medium, respectively. The PVKU grown probiotics enhanced growth and induced stem cell differentiationdue to HA content. Evidence of this differentiation was seen in the morphological shift from spindle to osteocyte-shapedcells after five days of incubation, an increase in ALP level over 21 days, and detection of intracellular calcium depositsthrough alizarin red staining-all indicative of osteoblast cell development.Conclusion: The osteogenic differentiation process in stem cells, improved by the nano-HA-containing byproducts ofprobiotic bacteria in the PVKU medium, represents a promising pathway for leveraging beneficial bacteria and theirsynthesised biomaterials in tissue engineering.

Background and objective: In recent years, the green synthesis of nanomaterials has received more attention than chemical synthesis due to its eco-friendly and compatibility. Material and methods: In this study Bacillus subtilis and Bacillus coagulans, two potential probiotics, were used and grown Bacillus in medium culture containing insoluble calcium phosphate produced nano-hydroxyapatite and nano-calcite. The nano-hydroxyapatite was purified from nano-calcite by heat treatment and washing with a 200 nm filter. The structures, characteristics, and elemental analysis of nano-sized material were studied by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscope, ultraviolet-visible spectroscopy, energy dispersive X-ray, and X-ray fluorescence. Results: The results showed that hydroxyapatite is made only in a medium containing insoluble calcium phosphate sublimated with urea which is induced phosphatase and urease. Here, for the first time, the braided bacterial nano-hydroxyapatite similar to the bone structure was made in the medium, which caused the production of urease and phosphatase (Maximum 99 U/L) enzymes, and the particle size was less than 100 nm. The ratio of calcium to phosphorus in crude hydroxyapatite and calcite crystal particles made by B. coagulans was 2.9, however, this ratio for pure hydroxyapatite was 1.7. Conclusion: Since the particles are made by antibacterial probiotics, the biological production of these particles makes them a suitable candidate to be used in food, toothpaste, and sanitation products. Braided hydroxyapatite can substitute the needle-like type of food additives for infants and elders due to its safety.

AbstractIntroduction: Hydrogen gas has great potential as a renewable energy source. Although hydrogen gas is obtained from fossil fuels, there is a demand for its production by chemical methods and electrolysis of water, and its extraction from oil sands is currently being studied. Its biological production is one of the cleanest types of hydrogen fuel production due to the consumption of greenhouse gases such as carbon dioxide and/or aerobic and anaerobic fermentation of agricultural wastes, and it can be considered as a solution for simultaneous production of the fuel and elimination of environmental pollutions.Materials and Methods: The present study briefly explains the hydrogen-producing microorganisms, the mechanisms, and the effective enzymes in their production. For this purpose, authoritative articles published between 2006 and 2021 and information in the Scopus database have been used to draw graphs and write this review article. In addition, some limitations and the ways to overcome them for increasing biohydrogen production are described in detail.Results: The results show that carbon dioxide fixation, fermentation, nitrogen fixation, aerobic and anaerobic photosynthesis are some ways of biological production of this fuel.Discussion and Conclusion: Important elements in biological production are the effective enzymes in these reactions and the possibility of using these enzymes in the continuous production of gas, and the purification of hydrogen from other gases. The stabilization of these enzymes under their conditions is of particular importance for the mass production of this gas. Purification of bio-produced hydrogen gas is essential for consumption as fuel, and some technologies, including nanomembranes such as polysulfonate, are very helpful in purifying this gas from other gases such as oxygen, nitrogen, ammonium, hydrogen sulfide, and oxygen.

Chronic wounds have made a challenge in medical healthcare due to their biofilm infections,which reduce the penetrance of the antibacterial agents in the injury site. In infected wounds,the most common bacterial strains are Staphylococcus aureus and Pseudomonas aeruginosa.Biofilm disruption in chronic wounds is crucial in wound healing. Due to their broad-spectrumantibacterial properties and fewer side effects, anti-biofilm peptides, especially bacteriocins,are promising in the healing of chronic wounds by biofilm destruction. This study reviews theeffects of antimicrobial and anti-biofilm agents, including bacteriocins and protease enzymes asa novel approach, on wound healing, along with analyzing the molecular docking between abacterial protease and biofilm components. Among a large number of anti-biofilm bacteriocinsidentified up to now, seven types have been registered in the antimicrobial peptides (AMPs)database. Although it is believed that bacterial proteases are harmful in wound healing,it has recently been demonstrated that these proteases like the human serine protease, incombination with AMPs, can improve wound healing by biofilm destruction. In this work,docking results between metalloprotease from Paenibacillus polymyxa and proteins of S. aureusand P. aeruginosa involved in biofilm production, showed that this bacterial protease couldefficiently interact with biofilm components. Infected wound healing is an important challengein clinical trials due to biofilm production by bacterial pathogens. Therefore, simultaneous useof proteases or anti-biofilm peptides with antimicrobial agents could be a promising method forchronic wound healing.

Hydroxyapatite (HA) has many applications in medicine, dentistry, diagnosis, drug delivery systems, sewage treatment, bone remodeling, concentrating bacteria, covering implants, and antibacterial activity. Despite the numerous current applications of calcium phosphate compounds, particularly HA, their producing methods are being investigated to find the best processes. Several chemical and biological methods are used in calcium phosphate compounds synthesis. Researches have shown that compared to micrometer models, nanostructured HA has higher mechanical features and better biocompatibility in the human body. These properties optimize when nanometer components of HA are in similar size and shape with the least agglomerations. Biomineralization by microorganisms, which is a bacterial route, is a recent HA synthesis method. This paper is a review on the biosynthesis of HA emphasizing microbial methods. In this method, some bacteria and mold could be used in the nanometer production of HA. This type of bacterium commonly has a high amount of alkaline phosphatase enzymes. Desirable similarity to natural HA in the human body is the noticeable features of bacterial HA. Uniformity in the shape and size of synthesized particles that have the same crystallization is of other merits. Producing bacterial HA is easily reachable, one-step, inexpensive, harmless, and with high purity, and contrary to chemical synthesis, does not need heat treatment and precise pH adjustment.

Background and Objective: Discarded as wastes, parts of the agricultural products can be used for feed productivity as well as management of animal feed production. Production of various products is possible using appropriate processing. The objective of the present study was to use laccase of Albifimbria viridis in degradation of agricultural residues and to produce compounds with herbicide properties. Material and Methods: The fungi were isolated from agricultural soils. The isolates were identified using morphological detection and PCR amplification of the internal transcribed spacer. Supernatants were collected from semi-solid cultures and laccase activity was assessed using 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) substrate. This was carried out using n-hexane and degradation of the agricultural residues was investigated using gas chromatography-mass spectrometry. Results and Conclusion: Growth of the fungal isolate in culture media with tannic acid was studied using scanning electron microscopy. In total, the isolate produced 50 U ml-1 laccase. Gas chromatography-mass spectrometry analyses revealed production of oxime, methoxy-phenyl and 2-cyclopenten-1-one for tannic acids, o-guaiacol, tetradecane, hexadecane, octadecane, octadecanoic acid, hexadecanoic acid and benzene, 1,3-bis(1,1-dimethylethyl) for sorghum seeds and 2-acetyl-5-methylfuran, phenol, 2-methoxy and benzene, 1,2-dimethoxy for wheat straw during fungal growth (0.73 mg ml-1). Results have shown that the laccase enzyme produced from Albifimbria viridis native strain is capable of hydrolytic cleavage of chemical pollutants from agricultural wastes for herbicide bioremediation. Conflict of interest: The authors declare no conflict of interest.

Objective(s): The multi-drug resistant bacteria and clinical infections are some of the biggest global concerns, so new drugs are needed. Antimicrobial peptides and lipopeptides are new bioactive agents with great potential that can become a new strategy for clinical applications.Materials and Methods: Some Bacillus strains were isolated based on hemolytic antimicrobial production from the soil. The extracellular proteins were extracted by acidic precipitation and chloroform/methanol method and analyzed by SDS-PAGE electrophoresis and stained with Sudan black. The black fragment was purified and characterized by FTIR, GC/MS, and HPLC analysis to demonstrate the presence of lipids and proteins. The anti-microbial ability and stability of the purified lipopeptide were assayed by the Kirby-Bauer method. Also, it was examined for metal removal.Results: A new Bacillus halotolerans strain SCM 034 with hemolytic antimicrobial production was isolated. According to GC/MS (detecting C16, C17) and HPLC (detecting leucine, glutamic acid, valine, arginine, glycine, and aspartic acid) data, the black fragment was lipopeptide. Polyacrylamide hydrogel containing lipopeptide and gel purified lipopeptide showed anti-microbial activities against S. aureus and S. cerevisiae that were stable for a few months. Also, the lipopeptide was useful for cation removal and decreased cobalt, nickel, and calcium by 10.81 %, 24.39 %, and 34 %, respectively.Conclusion: Production of antibacterial lipopeptide hemolysin from this strain is reported for the first time and according to the results, lipopeptides have unique properties with biomedical and pharmaceutical applications. Also, polyacrylamide hydrogel lipopeptide is a promising candidate for wound healing.

Purpose: There are number of reports available regarding defensins activity against mammalian cells besides their antimicrobial and immune regulatory activities. This study aims to investigate anticancer and apoptosis activity of the purified defensins from leukodepletion filters alone or in synergism with bacterial peptide, nisin, on prostate and colorectal cancer. Methods: Leucoflex LCR-5 filters were backflushed by an optimized elution system. Isolated granulocytes were sonicated and the supernatant treated before further purification by high performance liquid chromatography (HPLC). SDS-PAGE and western blot testing verified the fraction. Cell culture on PC-3 (human prostate adenocarcinoma), and HCT-116 (human colorectal carcinoma) were conducted following by MTT assays in addition to annexin flow cytometry for sole and synergistic effects with peptide nisin. Results: Viable and active neutrophils could recover, and α-defensins were extracted and purified. Combinations of an optimal dose of α-defensins and nisin showed a remarkable synergistic effect on cancer cell lines (over 90% and 70% for PC-3 and HCT-116, respectively). Conclusion: It also observed that less than 40% of both cells could survive after co-treatment with optimal dose. Also, apoptosis was increased after treatment by these peptides together. Annexin Vpositive populations significantly increased in percentage in comparison with control.

Objective(s): Bdellovibrio-and-like organisms (BALOs) are predatory prokaryotes that attack and kill other Gram-negative bacteria for growth and reproduction. This study describes the isolation, identification, biological properties, and bacteriolytic activity of the first Bdellovibrio bacteriovorus with a broad prey range from Iran.Materials and Methods: One BALO strain with high predatory potency was isolated from the rhizosphere soil using Enteropathogenic Escherichia coli as prey. It was identified and designated as Bdellovibrio bacteriovorus strain SOIR-1 through plaque assays, transmission electron microscopy (TEM), Bdellovibrio-specific PCRs, and 16S rRNA gene sequence analysis. Biological characterization and analysis of bacteriolytic activity were also performed.Results: TEM and Bdellovibrio-specific PCRs confirmed that the strain SOIR-1 belongs to the genus Bdellovibrio. Analysis of the 16S rRNA gene sequence revealed its close phylogenetic relationship with strains of Bdellovibrio bacteriovorus. The strain SOIR-1 grew within the temperature range of 25–37 °C and the pH range of 6.0–8.0, with the optimal predatory activity at 30 °C and pH 7.4. It had the highest and lowest bacteriolytic activity toward Shigella dysenteriae and Pseudomonas aeruginosa with a killing rate of 89.66% and 74.83%, respectively. Conclusion: Considering the hypothesis of bdellovibrios heterogeneity, identification of new isolates contributes to a deeper understanding of their diversity, their ecological roles, and their promising potential as living antibiotics or biocontrol agents. Bdellovibrios with broad bacteriolytic nature has not previously been reported in sufficient detail from Iran. The results of this study showed the great potential of native B. bacteriovorus strain SOIR-1 in the control and treatment of diseases caused by pathogenic Enterobacteriaceae.

Background and objective: Phytase is used in human and poultry additives. This enzyme is mostly produced by Aspergillus niger which is a plant pathogen. Phytase from probiotics is a good candidate for the food supplements. Materials and methods: Bacillus coagulans, as a probiotic, was used for phytase and phosphatase activities on phytin agar and Pikovskayas Agar. The sodium dodecyl sulfatepolyacrylamide gel electrophoresis and zymogram analyses of the extracted phytase enzyme were carried out. Probiotic cells with phytase activity were immobilized on chitosan extracted from shrimp shells and the efficiency was investigated and analyzed using scanning electron microscopy and Fourier transform infrared. Results and conclusion: In this study, Bacillus coagulans showed intracellular phytase activities from broken cells with Soluble Index of 2.5 on phytase specific media. Iron and zinc oxide nanoparticles accelerated the enzyme activity by 25%. Cells were precipitated using ZnO-chitosan nanoparticles and the enzyme activity was investigated on gels. Chelation of chitosan-metal ion increased the positive charge density of chitosan which was expected to enhance adsorption of zinc and teichoic acid on Gram-positive Bacillus coagulans; approved by SEM and FTIR. Cells immobilized on ZnO-chitosan promoted the enzyme activity by 28,800 U ml-1 gel. The entrapped cells were resistance to high temperature and pH. This complex not only included activities against Streptococcus agalactiae, but also dissolved insoluble phosphate and phytin, which has made this complex a good candidate for use as additive in human and animal foods. Conflict of interest: The authors declare no conflict of interest.

Purpose: Simple and cheap diagnostic kit development is one of the important aims of pharmaceutical developers and companies focused on public health improvement. The Bacillus subtilis spore surface-display technique is a genetic engineering method that is used to develop new-generation diagnostic kits applicable for the early detection of various types of diseases. In this study, we developed a novel simple, rapid, and inexpensive diagnostic paper-based kit to detect tyrosine in urine samples of humans and animals that is applicable for home or laboratory use. Methods: The B. subtilis spore-displayed tyrosinase system developed by genetic engineering methods was used to prepare a paper-based kit to detect tyrosine in urine samples of different groups of patients (i.e., patients with diabetes, diabetes with chronic kidney disease (CKD), and chronic kidney disease) for the detection of tyrosine during the acute disease phase. To confirm the sensitivity and specificity of the kit, tyrosine was also detected in urine samples using conventional liquid chromatography/mass spectroscopy. Results: Different concentrations of tyrosine (0.1–1 mM) were detected in urine samples based on visible changes of color from bright brownish-gray to dark brownish-gray within 1 hour. The kit could screen samples to distinguish the three groups of patients based on formation of a broad spectrum of colors reflecting the concentration of tyrosine. Conclusion: To the best of our knowledge, this is the first diagnostic kit with potential to rapidly diagnose various diseases related to the production of tyrosine in biological samples. This kit is not only widely applicable, including for personal use in the home, but is also appropriate as a part of standard screening tests and health protection programs in countries with limited resources.

It is necessary to reduce the amount of sulfur in fossil fuels due to direct impact of the quality of these fuels on the environment. In this research, a novel fungus strain of Exophiala spinifera, namely FM, was used to desulfurize dibenzothiophene (DBT) as a model cyclic sulfur compounds in oil and fossil fuels. HPLC analysis indicated that the fungus was capable of reducing 99% of DBT concentration in BSM medium after seven days. This fungus utilized DBT as a sulfur source by co-metabolism reaction with other carbon sources such as glucose. Exophiala spinifera was inoculated in BSM medium containing DBT with various carbon sources including ethanol, glucose, succinate, and glycerol. This fungus had the highest growth and desulfurization capability on glucose as a carbon source after 96 h. E. spinifera had best growth and desulfurization rates in 0.3mM DBT. Optimum DBT desulfurization and growth rate of this fungus was observed at 26-30 oC. Suitable pH for the optimum growth and desulfurization activity of E. spinifera strain FM ranged 4-5.

Introduction:From an industrial application or commercial point of view, glutamic acid is one of the most important amino acids and its microbial production has been reported from some bacteria. Regarding the role of probiotics to modulate human health and the ever-increasing demand of prebiotics in the food industry, in the current study, production of glutamic acid and folic acid from three probiotic bacteria (Bifidobacterium, Bifidobacterium bifidum, Sporolactobacillus) was evaluated for the first time. Materials and methods: MRS broth and exclusive media was used for probiotic culture. The glutamic acid was identified using thin-layer chromatography and folic acid production was measured by folate kit. Each bacterium in terms of quality and quantity were measured by high pressure liquid chromatography. Results: Production of glutamic acid confirmed is based on the thin layer chromatography analysis and high pressure liquid chromatography results. In addition, it was observed that all three probiotics produce folic acid. The prevalence of folate in Bifidobacterium was measured as 315 mg/ml that was more than two other bacteria. Discussion and conclusion: To the best of our knowledge, this is the first report of microbial production of glutamic acid and folate from the probiotic bacteria. These beneficial bacteria can be used as a good source for mass production of these valuable compounds.

Introduction:Polyhydroxyalkaniates (PHAS) are bacterial polymers that are formed as naturally occurring storage polyesters by a wide range of microorganisms usually under unbalanced growth conditions. Mechanical properties of PHAS make them suitable replacements for petrochemically produced bulk plastics (polyethylene, polypropylene etc.), but in contrast to these commodity plastics PHA are completely degradable to carbon dioxide and water through natural microbiological mineralization. PHAS can be produced by biotechnological processes under controlled conditions. Polyhydroxybotyric acid (PHB) was the first of thePHAS discovered and is the most abundant polyester found in bacteria. Materials and methods: First, a rich bacterial suspension prepared from poly(3-hydroxybutyrate), then the cells were broken down and ensure the absence of live cells.The cell free enzymes were added to M9 medium.Then the sample turbidity was measured at a wavelength of 600 nm and incubated at 30°C and centrifiuged at 120rpm. Next, the amount of PHB as well as solution turbidity were measured and compared with control. The physical and chemical analyzes of extracted PHB samples such as UV absorbtion, FTIR, HPLC and HNMR assesed and compared with standard sample. Results: In twelve days this experiment was conducted, from the third day, the amount of polyhydroxybutyrate was measurable and the highest polyhydroxybutyrate was gained on the tenth day. The level of PHB was constant. Moreover, the level of glucose was decreased gradually till the tenth day. By Physico-chemical analysis, production of polyhydroxybutyrate was approved. Discussion and conclusion: In this experiment, the reaction efficiency was 37.5 percent. Probably the rest of glucose could be changed to other intermediate compounds by other enzymes in the sample.Therefore, by purification of the enzyme, usage of specific substrate and optimization of conditions outside the cell could help the production of polyhydroxybutyrate continually. Production is very cost-effective, by this method.

Background and Objective: Time-temperature indicators are used in smart packaging, and described as intelligent tools attached to the label of food products to monitor their timetemperature history. Since the previous studies on microbial time-temperature indicators were only based on pH-dependent changes, and they were long-time response indicators, in the present work, a new microbial time-temperature indicator was designed by using the alpha amylase activity of Bacillus amyloliquefaciens vegetative cells.Material and Methods: The designed time-temperature indicator system consists of Bacillus amyloliquefaciens, specific substrate medium and iodine reagent. The relation of the timetemperatureindicator’ response to the growth and metabolic activity (starch consumption and production of reduced sugars) of Bacillus amyloliquefaciens was studied. In addition, the temperature dependence of the time-temperature indicator was considered at 8 and 28˚C. Finally, in order to adjust time-temperature indicator endpoint, the effect of the inoculum level was investigated at 8ºC.Results and Conclusion: In the designed system, a color change of an iodine reagent to yellow progressively occurs due to the starch hydrolysis. The effect of the inoculum level showed the negative linear relationship between the levels of Bacillus amyloliquefaciens inoculated in the medium and the endpoints of the time-temperature indicators. The endpoints were adjusted to 156, 72 and 36 hours at the inoculum levels of 102, 104 and 106 CFU ml-1, respectively. The main advantages of the time-temperature indicator is low cost and application for monitoring the quality of chilled food products.Conflict of interest: The authors declare no conflict of interest.

Background and Objectives: Microbial spoilage of juices and industries related with Alicyclobacillus are considerable international issues. This spore-forming bacterium causes changes in juices odor and taste. The isolation and identification of Alicyclobacillus contamination in juice producing and packaging industries has an essential role in the prevention and control of this type of spoilage bacterium in HACCP (Hazard analysis and critical control points ) manner.Materials and Methods: A thermo-acidophilic, non-pathogenic and sporeforming bacterium was isolated from mango juice. Preliminary identification of the isolates was based on morphological, biochemical and physiological properties. Identification at species level was made by PCR amplification. The influence of temperature in the range of 25-65°C in the growth of bacterium and in the range of 80-120°C in spore-resistant and heat resistant proteins was investigated and compared with other spore producing bacteria.Results and Conclusion: Phylogenetic analysis of the 16S rRNA gene sequencing indicated that the isolated strain constituted a distinct lineage in the Alicyclobacillus cluster and submitted to NCBI with access number Alicyclobacillus HRM-5 KM983424.1. The spores resisted 110°C for 3 h, and produced 28% dipicolinic acid more comparable to Bacillus licheniformis. Also they could produce 0.69 mg heat resistance protein after 1.5 h treatment in 100°C. The results showed that this strain could have biotechnological applications.Conflict of interests: The authors declare no conflict of interest.

Background: Chitosan is unbranched polysaccharide composed of D-glucosamine and N-acetyl-D-glucosamine. Chitosan, derived from shrimp shell, has broad antimicrobial properties against Gram-negative, Gram-positive bacteria and fungi. Methods: Chitosan was extracted from shrimp shell and studied for cell entrapment and anti-bacterial properties. The hydrogel chitosan was used as the beads for cell entrapment and chitosan beads were designed to deliver cells and nutrients. These data confirmed with flow cytometric analyses. Results: Experimental results exhibited that internal diffusion through the chitosan matrix was the main mechanism for whole gelation by TPP (Tri-polyphosphate). The minimum inhibitory concentration (MIC) for chitosan against Staphylococcus aureus and Escherichia coli was 16 and 32 μg/ml respectively. Conclusion: Despite the antimicrobial properties of chitosan, trapped bacteria in the gel network were alive and were chelated indicating that their access to the outside was limited.

Introduction: Oil is one of the most important energy sources that contain variety of organosulfur compounds that are combustible and can produce sulfur dioxide which will cause pollution over the atmosphere and the soil. Dibenzothiophene (DBT) is often used as a model for biodesulfurization studies and surfactant Tween80 increases the solubility of DBT in water that leads to higher consumption by microorganisms. Materials and methods: DBT specific UV spectrophotometry at a wavelength of 323 nm was used to evaluate the ability of isolated Exophiala spinifera fungus in removal of DBT. The effect of various concentrations of surfactant Tween80 on the growth of the fungus and DBT utilization was studied. Results: Exophiala spinifera was able to remove 100% DBT after 7 days of incubation at 30 ° C and 180 rpm shaking. The effect of different concentrations of surfactant Tween80 on growth and DBT utilization by this fungus was examined and it was observed that the presence of surfactant in the culture medium increased the growth and removal of DBT, therefore the amount of DBT utilized with 0.4% concentration of the surfactant was about 30% more than that utilized without surfactant. However, higher concentrations of surfactant Tween80 decreased the growth and consumption of DBT by fungi. Discussion and conclusion: Exophiala spinifera was isolated from oil contaminated soil and able to utilize toxic compound DBT as a sulfur source in the presence of other carbon sources such as glucose. So this isolated strain could be a good candidate for the petroleum desulfurization and it is the first report about desulfurization of DBT by fungus Exophiala spinifera. Growth and removal of DBT by fungus increased in the presence of surfactant Tween80. It can be concluded that the surfactant increases the total DBT transfer between the organic and aqueous phases and has a potential application in DBT bioremediation system by the studied fungus biocatalyst.

The effect of different carbon sources on bacterial cellulose production by Gluconacetobacter xylinus (PTCC 1734) and two newly isolated strains (from vinegar) under static culture conditions was studied. The production of bacterial cellulose was examined in modified Hestrin-Shramm medium by replacing D-glucose with other carbon sources. The results showed that the yield and characteristics of bacterial cellulose were influenced by the type of carbon source. Glycerol gave the highest yield in all of the studied strains (6%, 9.7% and 3.8% for S, A2 strain and Gluconacetobacter xylinus (PTCC 1734), respectively). The maximum dry bacterial cellulose weight in the glycerol containing medium is due to A2 strain (1.9 g l-1) in comparison to Gluconacetobacter xylinus as reference strain (0.76 g l-1). Although all of the studied strains were in Gluconacetobacter family, each used different sugars for maximum production after glycerol (mannitol and fructose for two newly isolated strains and glucose for Gluconacetobacter xylinus). The maximum moisture content was observed when sucrose and food-grade sucrose were used as carbon source. Contrary to expectations, while the maximum thickness of bacterial cellulose membrane was attained when glycerol was used, bacterial cellulose from glycerol had less moisture content than the others. The oxidized cellulose showed antibacterial activities, which makes it as a good candidate for food-preservatives.

Background : Kefir contains lactic acid bacteria (Lactobacillus, Lactococcus, Leuconostoc, Acetobacter and Streptococcus) and yeasts (Kluyveromyces, Torula, Candida, Saccharomyces ).Kefiran is the polysaccharide produced by lactic acid bacteria in kefir.Methods : Kefiran was prepared from milk containing 0.5% fat and 10 grams kefir grains and was separated from kefir by ethanol (0.02 gram) following entrapping the platelets to this polymer. Ligand of the platelet-polysaccharide was studied by FTIR.Results : FTIR results showed that the bands of C-O and C-O-C connections were formed and the polysaccharides had been attached to the receptors of the platelet glycoproteins (GP Ib,GPIIb / IIIa). Stability and encapsulation of the platelet and kefiran were assessed by Coulter Counter. Encapsulation of the platelets by polysaccharide at the beginning caused to reduce the number of platelets following by releasing of 50% of the platelets after 3 hours.Conclusion : The platelets were encapsulated in kefiran polymer and detected for bioavailability as new drug for surface bleeding. Also, kefiran has antimicrobial and antifungal properties. On the other hand, the existence of nisin in kefiran could be useful as an antibacterial lantibiotic.

Objective(s):Despite of wide range applications of polymeric nanoparticles in protein delivery, there are some problems for the field of protein entrapment, initial burst and controlled release profile. Materials and Methods: In this study, we investigated the influence of some changes in PLGA nanoparticles formulation to improve the initial and controlled release profile. Selected parameters were: pluronic F127, polysorbate 80 as surfactant, pH of inner aqueous phase, L/G ratio of PLGA polymer, volume of inner aqueous phase and addition of polyvinylpyrrolidone as an excipient. FITC-HSA was used as a model hydrophilic drug. The nanoparticles were prepared by nanoprecipitation. Results: Initial release of FITC-HSA from PLGA-tween 80 nanoparticles (opt-4, 61%) was faster than control (PLGA-pluronic) after 2.30 h of incubation. Results showed that decrease in pH of inner aqueous phase to pI of protein can decrease IBR but the release profile of protein is the same as control. Release profile with three phases including a) initial burst b) plateau and c) final release phase was observed when we changed volume of inner aqueous phase and L/G ratio in formulation. Co-entrapment of HSA with PVP and pluronic reduced the IBR and controlled release profile in opt-19. Encapsulation efficiency was more than 97% and nanoparticles size and zeta potentials were mono-modal and -18.99 mV, respectively. Conclusion: In this research, we optimized a process for preparation of PLGA-PVP-pluronic nanoparticles of diameter less than 300 nm using nanoprecipitation method. This formulation showed a decreased initial burst and long lasting controlled release profile for FITC-HSA as a model drug for proteins.

Introduction: Most of the plant growth promoting rhizobacteria (PGPR) such as Azopirillum if accompanied with strong cellulase producing bacteria such as Cellulomonas, their colonization may be increased and their host plants growth improved. Materials and methods: Six endophytic Azospirilla which isolated from three rice and three wheat cultivars and also one strain from commercial biofertilizer (Green Biotech Co.), identified by biochemical tests and 16S rDNA analysis and were studied on the basis of cellulase, pectinase and auxin production and also their chemotaxis toward rice and wheat cultivars exudates was investigated. Two cellulase positive (A5 and A6) and two negative (A2 and A3) strains were selected and their interaction with C. uda ATCC 491 on auxin production and colonization on roots were compared. Results: This study showed that none of the strains had pectinase activity, but the strain isolated from rice had more Carboxy methyl cellulase (CMCase) activity. Selected isolates and C. uda ATCC 491 showed chemotaxis toward roots exudates. In most of the isolates, rate of auxin production increased by coculture with C. uda ATCC 491. Also, it was determined that C. uda ATCC 491 promoted the colonization of Azospirillum without or with cellulase activity on rice and wheat roots, respectively. Discussion and conclusion: Co-inoculation Azospirillum with C. uda ATCC 491 improves plant root system due to stimulation or additive effect of auxin production and cellulase activity, followed by more uptakes of water and minerals by roots. Also, it raises the number of colonization niches for useful bacteria such as Azospirillum and finally quantitative and qualitative plant parameters.

Molecular methods such as 16S rDNA sequencing are relatively accurate but are costly and time consuming, therefore new alternative methods have been a matter of interst. FTIR (Fourier Transform Infrared) is one of these methods. It is a physico-chemical method based on measurement of molecular bond vibrations excited by infrared radiation at specific wavelength range. The aim of this study was to assess efficiency of FTIR in identification and taxonomy of methylotroph bacteria (most important group of chlorinated methane derivative degrading bacteria) and comparing it to 16S rDNA sequencing method. Of 30 isolated methylotroph bacteria, 7 were selected. Following amplification of a portion of 16S rDNA gene by PCR and sequencing, a phylogenic tree was constructed. By FTIR method, transmittance spectra of these bacteria were obtained in infrared region 400-4000 cm-1. FTIR data were analyzed by SPSS software. The dendrogram of FTIR data analysis was very similar to dendrogram of 16S rDNA sequencing. Results showed that FTIR can be used as an identification method but not yet for taxonomy. By introducing a standard method for FTIR data analysis, this method can be considered as an alternative to the 16S rDNA sequencing method.

Introduction: A variety of oxygen-transport and -binding proteins exist in organisms including bacteria, protozoans, and fungi all have hemoglobin-like proteins. In addition to dealing with transport and sensing of oxygen, they may also deal with NO2, CO2, sulfide compounds, and even O2 scavenging in environments. Also they detoxified chlorinated materials like P450 enzymes and peroxidases and use as a detector of nitrate and hydrogen peroxide. Pore-forming bacterial globins are interested for filtration. Materials and methods: Although there are data for bacterial toxin as a filter, here we used Agrobacterial hem to induce nano pore in the heme structure using point mutation. Results: Investigations showed that three amino acids leucine 76, alanine 83 and histidine 80 are important for pore formation in Agrobacterium hemoglobin. A point mutation on leucine 76 to glycine, histidine 80 to asparagine and alanine 83 to lysine step by step led to create the nano pore 0.7- 0.8 nm in the globin. Discussion and conclusion: These mutations in bacterial hemoglobin increase the stability when mutation is with it’s at pH7. This mutation decreases the aliphatic index however increase the stability index.

Silver nanoparticles have become one of the most commonly used nanomaterials in consumer products because of their effective antimicrobial properties and low toxicity toward mammalian cells. In the area of water purification, today nanoparticles are widely used for detection and removal of chemical and biological substances. Therefore by the growing use of nanoparticles, further research is certainly needed to study the behavior of them. In this study, the antibacterial and antibiofilm activities of colloidal nanosilver (average size: 40±10 nm) on the growth, cellular respiration and biofilm formation of pathogenic strains and the isolates from the cooling water of Isfahan Oil Refinery (A1 and A2) were compared with biocide E-265 which generally used in this refinery by microtiterplate method. The results showed that different concentration of biocide E-265 had no significant effects on the bacterial growth and even at 20 and 40 ppm showed 100% increase in the biofilm formation of the isolate A1. Also it is detected that low concentration of nanosilver (1-2 ppm) showed unique antibacterial and antibiofilm activities and can be suggested as a suitable biocide for the recirculating water systems.

Background: Recently re-emerging infections occur due to antibiotic-resistant bacteria. The use of bacteriocins as a substitute for currently used antibiotics is promising. The isolated nitrogen-fixing Bacillus bacteria might be a potential candidate strain as an alternative source of peptide antibiotics in the future. Methods: A total of 15 nitrogen-fixing Bacillus strains with antibacterial activity were isolated from soil samples. Bacteriocin-producing strains against the indicator strains were co-cultured and isolated. The antibacterial activity of bacteriocin was detected by spot-on-the lawn method with different bacteria. Effects of proteolytic enzymes, pH, and heat treatment on bacteriocin activity were also determined. Findings: All isolated spore forming Bacillus strains had an inhibitory effect on Listeria monocytogenes and Staphylococcus aureus. Some of them had an inhibitory effect on methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE). None of them had an inhibitory effect on Gram-negative bacteria. The antimicrobial compounds produced by these novel strains were inactivated by the proteolytic enzymes which demonstrated their proteinaceous nature. These bacteriocins were also active in a wide range of pH and temperature. Conclusion: In the present study, new bacteriocin-producing nitrogen-fixing Bacillus strains with anti-MRSA and anti-VRE activity were isolated from the environment and their biochemical properties were determined. Keywords: Nitrogen-fixing Bacillus strains, Bacteriocin, Methicillin-resistant Staphylococcus aureus, Vancomycin-resistant Enterococcus faecalis

Introduction: Polyphosphates, also called volutin granules, are linear polymers from orthophosphates linked by energy-rich phosphoanhydride bands that have been seen in bacteria, yeasts, fungi, plants and animals. These polymers are completely safe and nontoxic, and have numerous applications in food and drug industries.Materials and methods: Due to the great importance and wide range of the utilization of these polymers in various industries, several factors such as various carbon sources, carbon source concentration and phosphorus concentration were studied and optimized. In order to increase polyphosphate production in Bacillus megaterium strain G11. The optimization process was carried out with determination of the amount of polyphosphate accumulated in cell and phosphorus removed from the medium. One-way ANOVA and Tukey tests were used in order to determine whether there was a significant difference between data obtained in this research.Results: Growth of B. megaterium in the presence of sucrose (OD=3.026) was better than glucose (OD=2.616) whereas polyphosphate production and phosphorus removal from medium were higher in the presence of glucose (0.033 g g-1 dry cell weight and 1.61 g l-1, respectively). On the other hand, polyphosphate production and phosphorus removal from medium coordinately were decreased with increasing glucose concentration. Furthermore, in studying the effects of phosphorus, we faced two phases of rising and falling. Actually, the increase of phosphorus concentration (0.25-1 g l-1) in medium caused an increase in polyphosphate production and phosphorus removal from medium whereas both of them were decreased with a more increase in amount of phosphorus (1-4 g l-1). One-way ANOVA and Tukey tests showed that there was a significant difference (P

Introduction: Cell wall mycolic acids (MA) from Mycobacterium tuberculosis are presented as antigens that can be used to detect antibodies as surrogate markers of active Tuberculosis (TB) disease, even in HIV coinfected patients. The use of the complex mixtures of natural MA is complicated by apparent antibody cross-reactivity with cholesterol. Mycolic acid is not only related to diagnosis of TB disease but also similar structure of mycolic acid in saprophyte strains are excellent candidate for drug delivery especially for nasal spray. The aim of this work was to investigate the effect of cholesterol on mycolic acid synthesis and potential of saprophyte mycolic acid to drug delivery. Materials and methods: Toluene enrichment medium was used for isolation of mycolic acid producing bacteria. A fast growing, acid fast bacterium was identified by PCR reaction and the related sequence of 16S rRNA gene was deposited in the NCBI Genbank with accession number jn64433. Production of mycolic acid was investigated by high-performance liquid chromatography (HPLC) in different media. Results: Here the effect of cholesterol on biosynthesis of mycolic acids by saprophyte Mycobacterium isolated from marine water is was reported. HPLC analyses showed the mycolic acid extracted from saprophyte. Mycobacterium had one, early, cluster of peaks, like Mycobacterium tuberculosis and Mobacterium bovis.This strain is a fast growing bacterium and cholesterol might promote longer fatty acid production. Discussion and conclusion: The similarity between mycolic acid from isolated and patogenic mycobacteria offers that mycolic acid obtained from saprophyte Mycobacterium can be useful as a drug carrier. Addition of egg yolk to media induced longer fatty acid production by isolating that is suitable for delivery of drugs into the macrophage.

Bulking is the floation of sludge flocculent due to excessive growth of filamentous or non filamentous microorganisms in the process of wastewater treatment that can lead to further deterioration of treatment process and effluent quality. Nocardiaforms and Beggiatoa build-up are due to presence of excess oil component and sulfur in the system, respectively. Hence by identifying the main cause of bulking bacteria, we can recognize its formation and finding solutions to specific bulking control. This study was carried out to identify the main microorganisms responsible for the bulking at Isfahan oil refinery water recycling unite by using microscopical methods and buried (or contact) slide technique. Buried slide is a useful technique to analyze environmental samples in which a microscope slide is embedded in an expected sample. The contact slide method might have a bias toward selective colonization by using specific thin agar cover on the slide. By microscopic studying of different slides, identification of filamentous bacteria was carried out based on morphological characteristics and their reaction to different staining. Dominant filamentous bacteria were identified as nocardioforms actinomycete and Nostocoida limicola. Nostocoida limicola belongs to the genetic category of the budding Planctomycete. For the first time, the budding formations of these bacteria were clearly seen in contact slides in this study. Furthermore some relationships were found between the dominance of these bacteria and the conditions of the wastewater treatment plant, which based on them, the methods to specific bulking control could be obtained.

Use of low-cost biological methods for ammonia removal as partial nitrification has been attracted by many environmental engineering researchers in recent years.In this study the removal of ammonia in high concentration sewage based on both complete and partial nitrification with the different sub-cycles has been investigated in pilot-scale and the results were compared. Ammonia concentration in synthetic wastewater was about 900 mg-N/L and fixed and varible volume of reactor was 3 and 6 liter respectively to create a suitable hydraulic retention time of 1.05-1.55 days in the different cases. The results of ammonia, nitrite and nitrate measurements by spectrophotometer have shown that it is possible to achieve partial nitrification by controlling temperature, pH, and dissolved oxygen and having more sub-cycles. Ammonia specific oxidation rate was about 13 to 16 percent more in complete nitrification compared to partial nitrification and in this condition the percent of nitrite accumulation was reduced from 91 to 51 in 3 sub-cycles and from 81 to 30 in 1 sub-cycle. Furthermore, increase of sub-cycles number from 1 to 3 had significant effect on increasing ammonia specific oxidation rate from 29 to 32 percent in partial and full nitrification, respectively. Results of this study showed that this method will be used for high ammonia removal in side stream process in addition to low nitrite oxidation rate in partial nitrification as compared to complete nitrification

In this research, six isolates, including three from three rice roots (PxR1, PxR2 and StR1) and three from three wheat roots (PxW1, PxW2 and PxW3) were isolated as endophytic bacteria and except for StR1, all the isolates were identified as Pseudoxanthomonas based on phenotypic analysis including FTIR and PCR amplification of 16S rDNA. The results showed that PxR1, PxR2, PxW1 and PxW2 were all similar and belonged to a novel species of Pseudoxanthomonas, but PxW3 was from different species. StR1 belonged to a novel species of Stenotrophomonas. Two strains including Azospirillum brasiliense Sp7 (S1) and Azospirillum lipoferum (S2) were selected as standard strains and compared with those isolates however, phenotypic and genotypic analysis verified that those isolates were not Azospirillum. For the first time, it was indicated that Pseudoxanthomonas existed as an endophytic bacterium in rice root.

In this study, the nitrification process using enriched ammonia oxidizing bacteria was used for ammonium removal from coke wastewater of Isfahan Steel Company (ISCO). Influent and effluent samples containing ~600 mg l-1 ammonium and 2530-550 mg l-1 phenol were collected. For comparative assessment, ammonia removal was performed on artificial media in which removal of ammonium took a shorter time (8 days) than in the real wastewater. Ammonium removal efficiency from the effluent was higher than that from the influent due to the reduced phenol content in the former. The best result occurred in the treatment composed of effluent, enriched nitrifiers, and bicarbonate for which a record ammonium removal of 14 days was observed. MPN method was used to count and compare colonies of nitrifying bacteria in the samples. The enriched nitrifier sample containing 4.6×103 cell ml-1 was the best. The results show that phenol has inhibitory effects on nitrification. Carbonate ions and enriched nitrifying bacteria have positive effects on ammonium removal in all samples.

Removal of ammonium is very important due to its toxicity to the environment and human being. The wastewater of Isfahan Steel Company (ESC) Contains high concentration of phenol (maximum 3000 mg/l) and ammonium (maximum 2000 mg/l). Therefore its effluent In the range of 1400 mg/l was used in this study as a feed. Synthetic wastewater also used for the comparison of removal efficiency. The bioremediation of ammonium in wastewater treatment of Isfahan Steel Company is very low. In this study activated sludge and compost were used to remove ammonium from effluent of Steel Company and synthetic wastewater. The results showed the maximum removal of ammonium by using activated sludge and compost in combination with mineral salts and glucose and CaCl2 in the effluent of ESC and synthetic wastewater were found 38.7% and 75.7% of respectively. The application of activated sludge and compost in effluents containing low ammonium and toxicity is very significant. Overall, due to considerable efficiency and low cost, this process could be used for ammonium removal in industrial wastewater.

Phenol and phenolic compounds are environmental pollutants that are found in industrial wastewater of oil refineries, coal tar, and chemical plants. Presences of these compounds in Isfahan steal plant have serious consequences for regional environment. Biodegradation is the best and economic method for refinement of phenol contaminated sites. In this research 15 phenol-degrading bacteria strains were isolated from different sites of Isfahan steal plant wastewater. Five dominant strains named as B3, C1, C4, C7 and D14 that had high capacity to eliminate phenol. Effects of different concentrations of phenol (100-900 mg/ml) on growth. Respiration and biofilm formation of 5 dominant strains were investigated. All strains grown well up to 500 mg/l of phenol concentration and eliminated it. Strains B3 had the most growth and biofilm formation on 300 mg/l. The majority strains had the best respiration growth and biofilm formation in 400-500 mg/l of phenol concentration. At 24 hours incubation time up to 500 mg/l phenol of phenol was degraded and at 48 hours incubation time 900 mg/l of phenol was degraded. By using these strains it could be possible to reduce phenol pollutant in phenol refinement pools of the Isfahan steal plant.

مقدمه: کفیر پروبیوتیکی است که دانه‌های ژله‌ای قابل رشدی تولید می‌کند و شامل مجموعه‌ای از باکتری‌های اسید لاکتیک و مخمرها می‌باشد. این میکروارگانیسم‌ها به وسیله‌ی یک ماتریکس پلی‌ساکاریدی به نام کفیران احاطه شده‌اند. کفیران یک گلوکوگالاکتان منشعب محلول در آب است که دارای فعالیت‌های ضد باکتریایی، ضد قارچی و ضد توموری می‌باشد. روش‌ها: دانه‌های کفیر به طور مداوم در شیر پاستوریزه کشت داده شدند. پس از شستشوی دانه‌ها با آب مقطر استریل با دو دمای 50 و 100 درجه‌ی سانتی‌گراد و جدا کردن دانه‌ها، نمونه‌ها سانتریفیوژ شدند و پلی‌ساکارید با اتانول سرد رسوب داده شد و پس از حل کردن در آب مقطر داغ استریل، در نهایت لیوفیلیزه گردید. میزان پروتئین موجود در نمونه اندازه‌گیری شد. فعالیت ضد میکروبی عصاره‌ی کفیران در برابر چندین سویه‌ی معرف به روش انتشار چاهک بررسی شد. همچنین اثر آنزیم‌‌های پروتئولیتیک بر فعالیت ضد میکروبی کفیران بررسی گردید. یافته‌ها: هر دو نمونه (خالص‌سازی در 50 و 100 درجه‌ی سانتی‌گراد) دارای اثر مهاری بر رشد باکتری‌های معرف بودند. واکنش برادفورد نشان داد عصاره‌ی به دست آمده دارای پروتئین بود، ولی فعالیت ضد میکروبی آن تا حدی در برابر آنزیم‌های پروتئولیتیک حفظ شد. نتیجه‌گیری: در این تحقیق نشان داده شد که فعالیت ضد میکروبی عصاره‌ی کفیران به محتوای پروتئینی موجود در آن نیز بستگی دارد. واژگان کلیدی: پروبیوتیک، دانه‌های کفیر، کفیران، فعالیت ضد میکروبی

For evaluating the relative effects of some polluting salts on the measurement of cellulase activity assayed by 3,5-dinitrosalicylate (DNS) this study was done. Glucose and cellulase solutions have been treated with salts. Exoglucanase and endoglucanase were assayed by 3,5-dinitrosalicylate reagent. Measurement of reducing sugar by DNS indicator in the presence of Ca+2, Ba+2, Fe+3, Mn+2, Pb+2, Fe+2, Ag+1, Zn+2, Co+2, and Al+3 salts overestimated and in the presence of Mg+2, Cu+2, Cd+2, and Hg+2 salts underestimated the real contents. The intensity of DNS color and/or the reducing power of glucose increased by decreasing radius of hydrated cation of alkaline-earth elements (from Mg+2 to Ba+2) in glucose solution. Exoglucanase and endoglucanase activities increased in the presence of Na+, K+, Ca+2, Ba+2 and Mn+2 salts and decreased in the presence of NH4 + and Mg+2 salts. Among the trace elements studied, Fe+3, Pb+2, Fe+2, Ag+1, Zn+2, Co+2, and Al+3 were the most effective inhibitors of cellulase activity. These ions inhibited exoglucanase more than endoglucanase. The effect of most ions on cellulase activity may be related to negative or positive effect of them on the method of cellulase assessment. So, for a better data interpretation in the study of ion effects on the soil enzyme activity, both the effects of ions on the method of enzyme assay, and the effects of ions on the enzyme activity should be studied. Journal of Applied Sciences and Environmental Management Vol. 10(3) 2006: 93-96