maryam sadrnia

One of the best ways to remove toxic metals is to use bacteria resistant to these metals with a biological purification process. This research aims to isolate bacteria resistant to tin, copper, chromium, and nickel from industrial wastewater and their molecular identification.
wastewater contaminated with heavy metals was collected from electroplating factories located in Tehran province. The wastewater sample was cultured on LB Agar containing certain concentrations of heavy metals and the grown bacteria were isolated. In the grown bacteria, the minimum growth inhibitory concentration (MIC) of heavy metals was determined by the microbroth dilution method. The genomic DNA of two strains with the highest level of resistance, purity, and polymerase chain reaction was performed with the help of specific primers. The PCR product was sequenced and ribotyping was done.
9 gram-positive and negative bacilli and gram-negative coccobacilli were isolated from wastewater containing heavy metals. Two Gram-negative bacillus strains showed the highest resistance to heavy metals in the MIC test. Based on the sequencing results, these two strains were identified as Enterobacter and Pseudomonas.
Two strains with the highest resistance to four metals were isolated from the effluent of electroplating factories and phylogenetic evaluation was performed. These bacteria can be used in the biological treatment of wastewater containing heavy metals.

Microbial lipases are an important group of enzymes with biotechnology value. In the present research, an attempt was made to isolate and identify lipase-producing microbial strains from industrial wastewater samples. After taking samples from sewage and sewage from different places,16 colonies were isolated from these samples. The isolates were cultured in a specific culture medium containing Tween80 to check the ability to produce lipase enzyme. Enzyme activity was determined using the light absorption curve. In order to identify the isolates molecularly, ribotyping was performed. For this purpose, the DNA of the isolates was extracted and PCR was performed with the help of 16SrRNA gene primers. The PCR product was sequenced and the strains were identified using sequence blast in the NCBI database. Out of a total of 16 isolates, ten strains (62.5%) were able to produce lipase enzyme as a result of creating a transparent halo in the culture medium of the lipid test. Among these, two isolates with the same halo formation rate and source of isolation, which had the highest growth and activity after 144 hours were selected from the culture. Enzyme activity values for bacteria isolated from slaughterhouse effluent and garage effluent ranged from 2.99 to 22.65 and 3.73to 39.2 units/ml, respectively. Due to their very high lipase activity compared to the strains introduced in other researches, Aeromonas veroni and Copriavidus metallidurans bacteria are suggested as very suitable and efficient strains for the biological treatment of wastewater.

The efflux pump in Pseudomonas aeruginosa inhibits the effect of ciprofloxacin by releasing quinolones out of the cell. It is important to find compounds to inactivate or inhibit its activity to continue using the antibiotics. The present study was done to investigate using sertraline as an efflux pump inhibitor in P. aeruginosa to reduce antibiotic resistance.

P. aeruginosa strains were isolated from clinical sources and identified by routine microbiological methods. Resistance of the isolates to ciprofloxacin was evaluated by Kirby–Bauer test. Resistance breakdown was investigated by adding sertraline to the Moller Hinton agar medium and determining the zone of inhibition of ciprofloxacin. Minimum inhibitory concentration (MIC) by microplate dilution method and Minimum bactericidal concentration (MBC) by culture and MTT method were done for the isolates and ATCC 27853. The presence of the efflux pump was evaluated by the phenotypic method using sertraline and serial dilution method of the liquid medium in a microplate, on ciprofloxacin-resistant strains. The presence of the producing gene of this pump was determined by the genotyping method in resistant strains by performing PCR. The standard PAO1 strain of P. aeruginosa was used as a positive control.

This study was approved by the Ethics Committee of the Faculty of Medical Sciences of Islamic Azad University, Brojerd Branch (Code: IR.IAU.B.REC.1401.011).

Based on Kirby–Bauer test results, three strains were considered resistant to ciprofloxacin. MIC of drug-resistant strains was between 32 and 64 mg/ml and MBC was between 16 and 32 mg/ml. By performing electrophoresis on the PCR products, it was determined that the tested strains contained the mexA gene encoding the efflux pump. In the agar medium without sertraline, the zone of inhibition around the ciprofloxacin disc was zero, but after adding sertraline, the diameter of the halo increased to 25 mm. The minimum inhibitory concentration of ciprofloxacin in the isolates before adding 25 µg of sertraline was 128 µg/ml and after adding sertraline, it was 4 µg/ml.

It was concluded that sertraline inhibited the efficiency of the efflux pump in resistant P. aeruginosa isolates and reduced ciprofloxacin resistance.

The aim of the present study was to investigate antibacterial and antibiofilm activity of a few medicinal plants against oral bacteria. Salvia officinalis, Lippie citriodora, Mentha piperita, Echinacea purpurea and Matricaria chamomilla were extracted. Isolates from oral cavity were identified by microbiological and molecular methods. Minimum inhibitory concentration and minimum bactericidal concentration were determined by Broth microdilution method. The anti-biofilm activity of essential oils and extracts investigated and as a mixture by Broth dilution method. Toxicity of the herbal mixture was assayed by in Wistar rats treated with intradermal injection. Wound healing properties of the herbal mixture against infected wounds on the back of the rats were investigated. Anti-biofilm activity was investigated on tooth surfaces. Bacterial structure changes and fine- structure study were performed by light microscopy and Transmission electron microscopy. The lowest MIC and MBC for the plant mixtures was 0.0002 mg/ml belonged to Streptococcus pyogenes and the highest values (0.025 mg/ml) belonged to Eikenella corrodens. The essential oils of S. officinalis, L. citriodora and M. piperita, but not E. purpurea and M. chamomilla extracts, were able to remove the biofilms created by the studied bacteria. The herbal mixture was able to completely heal the wound skin of rats in 21 days (p It was concluded that the essential oils of S. officinalis, L. citriodora and M. piperita had significant effects on inhibition of oral bacteria biofilm formation.

Biodiesel methyl ester or ethyl ester is a natural oil that is very similar to diesel and can be used as an alternative fuel for diesel engines. Micro-algae are able to produce and store high amounts of lipids. In this research, the production of biodiesel fuel from microalgae was investigated in a biofilm and some of its physical and chemical properties were determined.this study, a mixture of microalgae cultured from stagnant water was compared in a photobioreactor at two light intensities of 8000 and 16000 lux and the amount of biomass produced. The biomass produced under the light intensity of 8000 lux after isolation and drying was subjected to a direct trans-esterification process and biodiesel was produced.Analysis of biodiesel constituents of fatty acids was determined using GC / MS. Some biodiesel characteristics, such as density, cloudy point, spin point, and freezing point, were also studied. The light intensity of 8000 lux was superior to the magnitude of doubling of cells, specific growth rate and biomass production compared to 16000 lux light intensity, and was used to produce microalgae biomass. The results of GC / MS showed that biodiesel resulting from transesterification of lipid micro-algae contained 50. 31% saturated fatty acid and 49.69% unsaturated fatty acid. Pallic acid saturated fatty acids (C16: 0) with 39.16%, acetatanic acid (C18: 0), 65.6%, arachidic acid (0.72% C20: 0%), margaric acid (0.17% C17: 0%) and acids The unsaturated linoleic fat (C18: 2) with 27.47%, acidulic acid (C18: 1) with 20.04 and palmitoleic acid (C16: 1) formed 25.2% biodiesel. The produced biodiesel was 0.853 g / cm3 and the cloud was cloudy and its dropping point was 3- and 10 ° C.The results of the study showed that the microalgae culture in the photobiovert can be minimized by minimizing the cost and time. Also, fatty acid profiles and biodiesel physical properties indicated that the micro-algae biodiesel was of high quality and direct steady-state exchange could be a good option for producing biodiesel, as compared to other methods.

 Zataria is one of the native plants of Iran which is widely used for the treatment of diseases among Iranians. In this study, we investigated the antimicrobial effects of Zataria essential oil on the skin bacteria in rats.

 Bacterial strains were isolated from the skin of 6 wistar rats and the antimicrobial effects of Zataria essential oil were evaluated by disk diffusion and microbroth dilution methods. In-vivo tests were performed to evaluate the antimicrobial effect of the essential oil by microbial culture as well as allergy tests on the skin of experimental rats compared to controls.

 Three bacterial strains were isolated from the skin of rats identified as Staphylococcus aureus, Corynebacterium and Staphylococcus epidermidis. Minimum Growth Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) for the two strains of Staphylococcus aureus and Corynebacterium were obtained 0.39 and 0.78 mg/ml, while for Staphylococcus epidermidis, they were 0.195 and 0.39 mg/ml, respectively. In-vivo test results showed the antibacterial effect of the essential oil on the skin bacteria and no inflammatory effects were observed under the allergy test.

 Zataria essential oil has antimicrobial effects on the skin infections in lower concentrations. The use of this essential oil as an antiseptic and preservative in cosmetics is recommended instead of chemical preservatives that generally have skin side effects.

Antibiotics resistance has recently increased. The aim of this study was the evaluation of antibacterial efficacy of Aloe vera carrier produced in microemulsion system in comparison with ordinary antibiotics against some Enterobacteriacea. The aquatic extract of Aleo vera was produced by the Soxhlet method and a nonocarrier in the microemulsion system was prepared by two emulsifiers. The clinical isolates of Escherichia coli, Klebsiella pneumoniae, Salmonella enterica, Shigella dysenteriae, Salmonella Typhimurium, Salmonella Paratyphi, Serratia marcescens, Proteus mirabilis, Enterobacter aerogenes, Citrobacter freundii and Morganella morganii were obtained from patients and were identified by microbiological methods. Diffusion disk was used for evaluation of antibacterial properties in comparison with selected ordinary antibiotics. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) for tested materials were determined using MTT in the Micro Broth dilution method. The results proved that effect of carrier on studied isolates is dependent on concentration level. The inhibitory effect of carrier in concentration of 15 µg/ml by 18 mm zone of inhibition for Klebsiella pneumoniae was comparable to Ceftazidime and Cefalothin. The lowest MIC and MBC determined by the Microbroth dilution method with MTT belonged to Klebsiella pneumoniae as 0.1 and 3 µg/ml and higher concentrations belonged to Enterobacter aerogenes at 7 and 15 µg/ml. The greatest effect of carrier of Aleo vera aquatic extract was observed for Klebsiella pneumoniae and the lowest effect belonged to Enterobacter aerogenes, Citrobacter freundii and Morganella morganii. It was concluded that the carrier of Aloe vera produced in microemulsion system was most effective and had equal effects in comparison with ordinary antibiotics against Enterobacteriacea

In this study, the effect of Myrtus extracts on 25 methicillin resistant Staphylococcus aureus (MRSA) and Escherichia coli ESBL strains isolated from patients were compared by two methods.

15 methicillin-resistant Staphylococcus aureus (MRSA) and 10 Escherichia coli ESBL isolates were used in this study. Fresh Leaves of Myrtus were collected from the herbal medicine farm. Extraction was performed using a reflux distillation. The effect of concentrations 0.195-100 micrograms per ml of Myrtus extract on clinical isolates was analyzed in disk diffusion method compared with micro broth dilution method and with MTT in 545 nm on an ELISA reader apparatus.
Findings: Inhibition zone diameter for the minimum effective concentration of 50 micrograms per milliliter in all isolates of ESBL and MRSA were as 8±1 mm and 11±1. Minimum Inhibitory Concentration (MIC) was 6.25mic/ml and Minimum Bactericidal Concentration (MBC) was determined 12.5mic/ml for E. coli ESBL. Furthermore, the amounts for MIC and MBC was determined as 12.5 and 25 mic/ml, respectively for Staphylococcus aureus.

The results of this study showed compliance of two methods in evaluation of drug-resistant clinical isolates. It was proved that the disk diffusion method could be determining range of effective concentration but micro broth method determines the effective concentration carefully. It is recommended that results obtained from disk diffusion not to be basis for final decisions in traditional medicine studies. Bacterial behavior in the broth and determination of the point of death greatly increases the accuracy of the results.

Aflatoxins are natural fungal toxins produced by Aspergillus species such as A. flavus. The toxins are poisoning and can cause tissue necrosis and liver cancer. The aim of this study was to determine the control of Aflatoxin B1 production by extracts and essential oils.
Aqueous extracts were prepared by heating and essential oil by Clevenger's apparatus. Antifungal activity of essential oil and aqueous extract of Mentha pulegium and Satureja hortensis were determined by disc diffusion and microplate dilution methods. Production control of Aflatoxin B1 was investigated with concentrations under MIC(Minimum inhibitory growth concentration) of two materials and were determined by HPLC method.
The most zone of inhibition was 10% belonging to Satureja essential oil and its aqueous extracts with diameters of 26mm and 12mm, respectively. These values for Mentha extract and 10% essential oil were 18mm and 8mm respectively. MIC of the aqueous extract of Satureja and Mentha were 0.031 and 0.063mg/ml respectively, and 1% essential oil of two materials was 0.039 and 0.078 mg/ml, respectively. Aflatoxin B1 produced by A. flavus in concentrations of 1%, 2% and 10% Satureja essential oil were 122, 113 and 134 ppb, in 1%, 2% and 10% Mentha were 163, 168 and 171 ppb, respectively. The aqueous extracts of 1% Satureja reduced the production of toxin as 58.1 and the 1% aqueous extract of Mentha as 39.6.
The results of this study showed that both Satureja hortensis and Mentha pulegium have the ability to inhibit the growth of Aspergillus flavus fungus, as well as control of aflatoxin B1 production in low concentrations and recommended for further studies.

Today, due to the occurrence of drug resistance and the ability of bacteria to develop acute infections, investigating the antimicrobial effects of herbs has been proposed. Therefore, we aimed to examine the effects of Hypericum perforatum extract and microemulsion and Aloe vera extract on Brucella bacteria.
This experimental study was carried out with the help of a hood in a biosafety level 2 laboratory. Fifty blood serum samples were cultured in BACTEC for brucellosis, and if grown, they were transferred to Brucella Agar in an anaerojar containing 10-5% CO2 for 48-72 h. Biochemical validation tests were carried out on the grown samples. Extraction was performed by a reflux (distillation) apparatus in a 1 liter balloon and a 40 cm spiral arm. Microemulsion structure was prepared by emulsifiers from the extract. Afterwards, 1, 8.4, and 2 mg/L dilutions of the aqueous extracts of Hypericum perforatum and Aloe vera were prepared, and the antimicrobial properties of these extracts were evaluated by disc diffusion, pour plate, and extraction methods on pure culture of Brucella isolated from patients.
Evaluation of antimicrobial effects on the isolated Brucella strains showed that the mean diameters of the zones of inhibition in the studied strains for the of 8-1 mg/l concentrations of Hypericum perforatum extract were 36.6±2 and 18±3 mm, respectively, and for Aloe vera they were respectively 30.7±3 and 18±1 mm. None of the strains formed an inhibition zone at the 0.5 mg/l concentration. Evaluation of the effect of the extract in the well diffusion method also yielded similar results, but in the pour plate method, the effect of the extractes on the bacteria was not observed. Micoemulsion of the Hypericum perforatum extract did not have any effect because of over dilution.
The disk diffusion method under biosafety level 2 laboratory was highly effective, and the extract of Hypericum perforatum had the highest effect on Brucella; therefore, it is recommended for clinical studies.

Mutations in pncA and gyrA genes cause pyrazinamide (PZA) and fluroquinolone resistance in Mycobacterium tuberculosis (MTB). In the present study, structures of pyrazinamidase (PZase) and DNA gyrase proteins were studied in resistant and susceptible clinical isolates of MTB.
Sixty clinical isolates of MTB were used in this study. Polymerase chain reaction (PCR) amplification of pncA and gyrA genes was accomplished on purified DNA. Sequence of the fragments was determined by an Applied BiosystemsTM apparatus. Bioinformatic analysis was performed by online software and three-dimensional (3D) structures of proteins was predicted using Molegro Virtual Docker (MVD) Modeler software.
Amplified 744 and 194 bp fragments of pncA and gyrA genes, respectively were yielded suitable sequence results. Predicted 3D structures of proteins showed some differences between wild-type and mutant structures. Mutation in amino acid No.31 (T92C) caused an increase in distance from metal ion position to enzyme active site, but it was considered as a polymorphism. Docking results by MVD revealed a relationship in quinolone resistance-determining regions (QRDR) amino acids in interaction with antibiotic. T92C mutation in PZase from non-polar aliphatic amino acid Ile (ATC) to polar aliphatic amino acid threonine (ACC) was a polymorphism.
Structural changes in two important proteins related to drug resistance were proven in clinical isolates of MTB.

Streptomycin is one of the most efficient treatments of tuberculosis that increasingly reported its drug resistance. The most common mutations associated with drug resistance to streptomycin of Mycobacterium Tuberculosis، causes tuberculosis، and occurs at codons 43 and 88 of rpsL gene. The purpose of this study is study of alterations in rpsL gene with two restriction enzymes BsajI and MbooII related to drug resistant to streptomycin in clinical isolates of mycobacterium tuberculosis. This study was performed using 71 clinical isolates of Mycobacterium tuberculosis. Molecular PCR-RFLP methods were designed with two enzymes BsajI and MbooII for mutation analysis at codon 43 of rpsL، in resistant and susceptible strains، respectively. Finally، the results were compared with sequencing and phenotype strains. 25 subjects were studied with enzyme BsajI. This enzyme is capable of detection 64 percent of resistant and all sensitive strains. 46 strains were examined by enzyme MboII. This enzyme detected almost 91 percent of sensitive strains. MboII is selected for detection of sensitive strains (unlike BsajI). Results of sequencing rpsL genes in investigated strains، showed fully consistent with the results of PCR-RFLP and proved mutation in codon of 43 of thin genes in studied strains. The results showed that the PCR-RFLP with designed restriction enzymes can be used as a rapid، simple assay، and has high sensitivity for differentiation of Mycobacterium tuberculosis strains that are resistance to Streptomycin.

Early detection and suitable drug admission are the first attempts to control of TB and MDR-TB. In this study, PCR-RFLP method was used for rapid detection of Mycobacterium tuberculosis and resistance to isoniazid. In the present study, 87clinical isolates of MTB were used in a PCR-RFLP method. The RFLP-PCR assay by specific primer was used for two purposes; In the first, PCR of katG gene for diagnosis of bacteria and in the second step, PCR product by endonuclease enzyme in a RFLP reaction produced a pattern in electrophoresis for mutation detection in katG315. Sequencing method was used for confirmation of RFLP results. The study showed that all studied strains produced band 620bp that confirmed MTB. From the 46 resistant strains to isoniazid, the RFLP-PCR method showed that 44 strains had mutations in the katG gene Ser315Thr. The 41 susceptible strains had not any mutation at the codon. Results of sequencing were confirmed results of the molecular method. Sensitivity of RFLP-PCR test was 95.6% (95% CI: 0.85-0. 98) and specificity was 100% (95% CI: 0.91-1. 0). RFLP-PCR test is a good tool for simultaneous diagnosis and detection of katG315 mutation in clinical isolates of MTB.

Background and Molecular detection of antibiotic resistance in clinical strains of M.tuberculosis is of great importance. In this study, we developed a method for rapid detection of mutations resistant to the rifabutin antibiotic resistant gene. In this study 40 clinical isolates of M.tuberculosis including 12 resistant and 28 susceptible isolates to rifabutin were used. The isolates were obtained from Tuberculosis and Pediatric Infectious Research Center affiliated to Arak University of Medical Sciences. Specific primers were designed and corrected by BLAST-IDT and MEGA software. The primers for an Allele Specific PCR was able to detect the desired hot point in the gene from 3´end in 516 526-531 codons and could also reconnoiter mutant state; Therefore, lack of formation of band in PCR product indicates the resistance of strain to rifabutin. Some selected samples were sequenced and compared with results derived from ASP. 12 M.tuberculosis isolates resistant to rifabutin, mutations in one of the three main codons were detected in 10 strains using Allele Specific PCR method. Susceptible strains did not show any mutations in these codons. The sensitivity of the method was 80% (95% CI: 0.55 0.95) and the specificity was 100% (95% CI:0.87-1). Results of sequencing were concordant with results of ASP method. The results showed that Allele Specific-PCR was a rapid and simple method for fast detection of rifabutin resistance in M.tuberculosis isolates and is recommended for routine works.

Quarterly Ammonium Compounds (QuAC) are the more effective antimicrobial agents in medicine and industry. It needs to produce the new compounds with the wider spectrum and less toxicity, because of microbial resistance. Aim of this study was microbiological Evaluation of the new Quarterly Ammonium Compounds produced by Structural modifications on some bacteria, yeast and fungi. 16 Quat salts were designed and made in Ethanol or Aceto Nitril. Minimum Inhibitory Concentration (MIC) was determined by standard method on Nutrient Broth and Minimal agar culture media for bacteria, Potato Dextrose Agar (PDA) for fungi and Nutrient Agar and Saboro Dextrose Agar (SDA) for yeasts. Compounds 2,7,8,9,12,13 has the more antimicrobial effect (minimum of MIC). Furthermore, it was shown that MIC was unrelated to culture compounds. In yeast culture it must to increases the concentration in enriched media. Compounds 9,12 and 13 has the more antibacterial effect as well as antifungal effect. In comparison of structure of produced compounds and results of the study, it was revealed that radical R3 has the most important role in antimicrobial properties of Quats and it could to be substitute any suitable group related to increasing anti microbial effects.

Nowadays, with the development of drug resistance, the use of herbs as an alternative to chemical drugs is considered by researchers. In this work, effects of Aloe vera extracts on clinical isolates was studied. Aloe vera plant medicinal plants were obtained from a greenhouse. Three extracts including essential oils, extracts and no essential oils and essential oil extraction method also includes a complete extract of Aloe vera were prepared Percolation total. To investigate Microbiology extracts of two strains of Staphylococcus aureus and Staphylococcus epidermidis clinical strain of Gram-positive and Gram-negative isolates of Klebsiella pneumoniae and Escherichia coli strains Staphylococcus aureus ATCC25923 were used as well. Evaluate the effect of two Kirby-Bauer disk with the minimum inhibitory concentration (MIC) was performed using microplate dilution. Turbidity was determined by an ELISA reader apparatus. All extracts of aloe vera on Klebsiella with a diameter of 32 ± 2 mm mg/ml285.7 concentration with microplate dilution method was 2.23 mg/ml. Staphylococcus aureus and MIC zone diameter of 30 ± 2 mm and mg / ml 2.23, Staphylococcus epidermidis and Escherichia coli mg/ml4.46 mm 17.85 mm 30 ± 5 mg / ml 17.85 respectively. Similar concentration of 17.85 mg ml Aloe Vera with a circle formed by the disk mc / ml 10 gentamicin was shown. This effect is similar to other bacteria antibiotics gentamicin, clindamycin, erythromycin, and Cefixime compared with Aloe Vera extract has been proven. Essential oils made from all parts of the same whole extract of aloe vera, but not essential extracts, bacteria studied were ineffective. In this study the effects of similarity and some excess water Asrsarh Aloe Vera with common antibiotics on bacteria causing the infection was confirmed. Therefore, by production of appropriate pharmaceutical plant drugs with fewer side effects, bacterial infections couled be treated properly.