جستجوی مقالات مرتبط با کلیدواژه "coliform" در نشریات گروه "پزشکی"

In recent years, iron nanoparticles have been successfully used to remove water pollutants. Fecal coliform is one of the parameters that reduces water quality and its removal is essential. The aim of the present study is using nanoscale zerovalent iron particles to enhance the usual sand filters in removal of fecal coliform of groundwater in Ilam city.

Water samples were collected from several active wells in Ilam city. The parameters of hardness, probable and fecal coliforms were measured. Afterward, samples of fecal coliform contaminated-water were passed through filters with different values of zerovalent iron nanoparticles (0.5-3 gr) and parameters were remeasured.

The results of this study showed that by increase of iron nanoparticles, the removal efficiency of coliform was increased, so that, in most samples, by increasing the iron nanoparticles to 3 gr, the coliform content reached to zero. The degree of hardness was initially reduced when the amount of iron nanoparticles increased, but over time, the reduction trend was halted.

In general, the results indicate that not only zero-valent iron nanoparticles are capable enough to remove microbial contamination from water, but also they can be used to completely purify the groundwater and also to reduce other contaminants including chemical pollutants to a permissible threshold, especially in small regions where complex water treatment plants may not be available.

Salmonella species is one of the important pathogens causing food poisoning and gastroenteritis. The aim of the present study was to assess the quality of traditional creams as regards bacterial contamination.

This was a cross-sectional study including a total of 250 traditional cream and 50 pasteurized cream samples collected in the south of Tehran retail shops. The samples were diluted in a phosphate-buffered saline, transferred to a rappaport-vassiliadis salmonella (rvs) enrichment broth according to the CDC procedures and incubated at 37° C in Hektoen enteric agar and bismuth sulfite agar media for 24 hours. Antimicrobial susceptibility testing was done using the Clinical and Laboratory Standards Institute (CLSI) procedures. On the following day the suspected colonies were examined for phenotype and finally confirmed by the API 20 E test.

Of the 250 unpasteurized cream samples 15 (6%) were contaminated with Salmonella. Of the 7 serotypes identified, the most frequent Salmonella serotype was the infantis serotype with 7 cases (33.3%). Furthermore, Coliform bacteria such as Escherichia coli, Enterobacter, Klebsiella and Citrobacter were also isolated. The highest antibiotic resistance was to nalidixic acid (93.3%), tetracycline (73.3%) and trimethoprim (66.7%). None of the pasteurized cream samples was contaminated with Salmonella.

The results confirm the need for more effective control and monitoring of the traditionally prepared cream marketed in the city by the Food Control Authority. In addition, educating the public about the consumption of pasteurized cream can play a good role in reducing foodborne illnesses.

Water contamination of baths causes gastrointestinal, skin and fungal diseases due to pathogens. Therefore, this study was conducted to determine the microbial contamination of natural swimming places water in Behshahr.

The present descriptive study was performed in three natural swimming places. Nine-tube fermentation method was used to determine the bacterial contamination of coliforms, and membrane filtration method was used to measure enterococci. Pearson's correlation coefficient was used for data analysis. 

Total coliforms in 2 samples (22.22 %) were undesirable and in 7 samples (77.78 %) desirable; thermophilic coliforms in one sample (11.11 %) were undesirable and in 8 samples (88.89 %) desirable; and intestinal enterococci in one sample (11.11%) were undesirable and in 8 samples (88.89%) desirable. There was a significant relationship between total coliforms and fecal coliforms and total coliforms and intestinal enterococci (p = 0.001).

Totally, bacteriological contamination index was desirable in the investigated natural swimming places, but in a limited number of samples, the contamination indices were higher than the standard. Funding This study did not have any funds.

 None declared.

This project was not registered. How to cite this article: Amouei A I, Jafari Atrabi M , Fallah S H , Asgharnia H A, Aghalari Z. Survey of Microbial Contamination of Water in Natural Swimming Places of Behshahr in 2017: A Short Report. J Rafsanjan Univ Med Sci 2019; 18 (8): 839-48. [Farsi]

Trachyspermum capticum plant is from Apiaceafamily of essential oil and seed extract of this plant contain compounds that show its biological properties. The aim of this study was to investigate and compare the antimicrobial activity of essential oil and methanolic extract of herbs. The chemical compounds of this medicinal plant were analyzedby GCMS and 7 components were identified, representing 85% of its total essential mass. The antibacterial properties of these agents were evaluated by determining the minimum inhibitory concentration (MIC) and minimum inhibitory concentration (MBC) against E. coli and Enterococcus faecalis bacteria with microdillution method, and the functional groups of the compounds were investigated using FTIR analysis. Results showed that the EO Trachyspermum capticum was formed by the main components of (Thymol 30%), (Limonene 21%) and (gamma-terpinene 19%). Factor groups derived from the resulting curves indicate that the flavonoid compounds in the extract have been shown to have antioxidant and antimicrobial properties. The results for the methanolic extract (MIC) were 15.62 mg/ml against enterococcus faecalis bacterium and 31.25 mg/ml against E.coli and MBC 125 mg/ml against enterococcus faecalis and 5.62 mg/ml is obtained against Escherichia coli bacteria. MIC and MBC of this species were found against Enterococcus faecalis 5 mg / ml bacteria and against E. coli (0.625mg/ml). Essential oils and its methanolic extract play an important role in antimicrobial activity and its essential oil is much stronger than its extract. The presence of flavonoids in this plant is due to this biological property.

The water which is prepared for specific uses and has lost its quality is called wastewater. Wastewater of hospitals and health centers contains different pathogens that reveals the necessity of attention to this pollution sources. Therefore, this study was designed to evaluate the antibiotic resistance pattern of bacteria isolated from hospital wastewater treatment plant. In this descriptive study (in 2015), the samples of wastewater were collected from the hospital aeration ponds in different seasons. Samples were transferred to the laboratory under standard conditions. The bacteria count were performed by multiple tube test and were reported according to MPN (Most Probable Number) method. Microbial identification tests were performed according to conventional methods. The investigation of antibiotic resistance was performed using Kirby– Bauer standard technique according to method of Clinical and Laboratory Standard Institute 2014 (CLSI). Data were analyzed by SPSS software. In this study, a total of 20 samples were collected in different seasons. Despite more cases of isolated coliforms, the count of enterococci was higher than that of the coliforms.The highest resistance to ceftazidim (100%) and trimethoprim (85%) was observed in Enterococcus and Coliforms, respectively.
The highestsusceptibility to meropenem, imipenem, gentamycin, and ceftazidim (100%) was observed in Pseudomonas. Also, in the spring and autumn, the antibiotic resistance was higher than in the other seasons. It is necessary to pay attention to the sources of contamination in order to prevent increasing the burden of contamination of highly resistant bacteria. In addition, it is necessary to conduct a national survey to determine phenotypic and genotypic resistance patterns of bacteria in Iran

Background and Waste stabilization pond is one of the conventional wastewater treatment processes especially in warm climate regions. This study investigated the effect of baffle and attached growth on improvement of coliform removal efficiency.
This research was carried out in pilot scale adjacent to wastewater treatment plant in Ahvaz, Iran. The pilot composed of a control system and three other systems. In control system two ponds were serially connected. Dimension and configuration of other three systems were similar to those of the control system. However, the ponds in these systems were equipped with various baffles and fixed bed media. Within four months, the capability of each system in coliform removal was evaluated in various detention times and coliform die-off coefficient (Kb) of each pond was determined.
During sampling with average detention time of 8.7 day, the average of coliform removal was 69% in control system, while it in two, three and four baffles system these values were 80, 84 and 86%, respectively. Also, Kb20 average in the first pond of control system was 0.11 d-1 and in other systems with increasing of baffles and media packages number to two, three and four it increased to 0.16, 0.17 and 0.18 d-1, respectively. Furthermore, Kb20 in second pond was higher than first pond of each system.
Use of baffles and fixed bed media improved coliform removal efficiency. The efficiency of two and three baffles system was more than that of the control system and was found to be better than four baffles system technically and economically

Objectives Based on the significant progress made on the field of membrane technology, the application of this technology has rapidly increased. The current study aimed at assessing the physicochemical and microbial quality of the desalinated water provided by the private sector (Esin) in Saveh, Iran. The results of the current study were compared with the guidelines of Institute of Standards and Industrial Research of Iran (ISIRI).
Methods A finite time service was studied based on a total of 15 samples a day. The period of study was about 7 months from 2014 to 2015. Physical and chemical tests were performed according to the standard methods of water and wastewater. Total coliform bacteria and fecal coliform tests were conducted by multiple tube fermentation method and the total number of heterotrophic bacteria was investigated by the pour plate method.
Results Results showed the values of physical parameters as turbidity 0.10 (nephelometric turbidity units) NTU, chemical parameters as electrical conductivity (μs/cm), total hardness, calcium (CaCO3) hardness, magnesium hardness, alkalinity, calcium, magnesium, fluoride, phosphate, nitrate, nitrite, sulfate, potassium, sodium, chloride, and residual chlorine (mg/L), and pH were 476, 103.06,78.89, 9.80, 76.42, 37.28, 2.45, 0.11, 0.10, 8.3, 0.003, 37.71, 0.37, 68.23, 62.19, 0.74, and 7.60, respectively. Values of microbial parameters were total coliform 0, fecal coliform 0, manufacturer part number (MPN)/100 mL, and heterotrophic plate count (HPC) 2.5 CFU/mL.
Conclusion The obtained results indicated that the quality of desalinated water provided from the water desalination plant of Saveh is approved and no health threatening factor was found. The concentration of measured parameters in the study was satisfactory and acceptable, based on IRISI guidelines.

Aims: Leachate is a type of highly concentrated wastewater containing chemical and microbial contaminants. Leachate discharged in receiving earth and water leads to the diffusion of different types of dangerous environmental pollutions. The aim of this study was to reduce the coliform bacteria in fresh urban leachate through electrolysis equipped by copper-iron combined electrodes.
In the laboratory-experimental study, 36 fresh leachate samples were prepared from urban solid-waste collecting trucks in Gonabad using standard combined method from July to November 2015. The leachate samples were poured into a closed reactor containing three copper-iron combined electrode pairs. Data was analyzed by SPSS 18 software using one-way ANOVA.
Findings: The higher the voltage and reaction time were, the higher the coliform removal was. In 60 minutes, all three voltages removed 100% of microbial pollution. There was a significant difference between the rate of the removed coliforms through different voltages in 15, 30, and 45 minutes (p Through the utilization of copper-iron combined electrodes and applied proper voltages, the electro-chemical method can be used as a clean and eco-friendly method to remove the coliform bacteria from fresh leachate.

Hospital waste water due to infectious organisms and other risk factors is important. In this study, the possibility of coliform bacteria removal from hospital waste water using ozone separately and combining with hydrogen peroxide (H2O2 + O3) as a pre-treatment was investigated. This is an experimental study that in the second moiety of 1392 in Kerman University of Medical Sciences and Engineering Research Center for Environmental Health Institute of the East Azerbaijan province was executed. Hospital microbial load in raw waste water,ozone disinfected and advanced oxidized raw sewage was determined by 9-tube most probable number(MPN) method. Average coliform bacteria and fecal coliform in raw sewage samples from 10 hospitals respectively 3.6×105 and 2.5×105 MPN were calculated. Coliform and fecal coliform removal efficiency of hospital wastewater by ozonation method back in time 10 and 20 minutes respectively (99.79 and 99.91%) and (99.99and 100%). was. Also, removal of coliform and fecal coliform wastewater advanced oxidation hospitals with contact times of 10 and 20 minutes (99.98 and 99.99%) and (100and 100%), respectively. The trial showed that the effective performance both ozone disinfection and advanced oxidation process (O3 + H2O2) as a pre-treatment is the removal of total coliform bacteria. However, the same results were obtained with a single injection of ozone. It is recommended that the hospital wastewater treatment in order to removal of total coliform bacteria only be done with ozone disinfection.

Limitation of water resources and probability increase of waters pollution resulted from human activities have leaded intensification of control plans for quality of waters. Excremental pollution of water resources is one of substantial problems which their recognition is of great importance in preventing epidemic digestive microbial diseases. For the purpose of conducting study and determining the quality of waters in wells and springs existing in north-west area of Eghlid, sampling was performed from 10 wells and springs in north-west of Eghlid in July 2013 and March 2014, and the water samples of this region were assessed respecting to existed indexes of coliform. The results showed that the microbial pollution of springs in July was rather than March. Also, the results indicated that average coliform existing in springs was more than the world standards, and some of the springs did not have appropriate quality, so that 10% of samples had coliform pollution, which were related to Ghormas-Beigi spring, and 10% of samples had non-coliform microbial pollution, which were related to Hosseinak aqueduct. The reason for further average of coliform in springs, in comparison to the world standards, is the pollution of springs with different types of human and bestial sewages which are resulted from the residency of nomads and farmers in the environment of springs.

Water scarcity and increasing demand for various applications has led to more attention to the treatment and using potential resources. Surface water is one of water resources in the societies. In the present study, the performance of two coagulants, Alum and Ferric chloride, was considered to determine turbidity, color, COD, and microbial reduction in the surface waters in Tehran.
Sampling was carried out from two surface waters named Sorkhehesar and Salehabad, during summer, fall, and winter. After optimization of coagulant dosage and pH, jar test experiments were conducted, and turbidity, COD, color, and microbial changes were considered.
Turbidity range in Sorkhehesar and Salehabad was between 91 and 500 NTU, and 35 to 400 NTU, respectively. Optimized dose of alum for summer, fall, and winter was 45, 100, and 35 mg/L, respectively, while in case of ferric chloride the optimized dose for three studied seasons was 5, 70, and 10 mg/L. Optimized dose of alum and ferric chloride in Salehabad, was determined as 28, 115, 2 and 30, 65, and 5 mg/L. Turbidity removal efficiency using both coagulants was higher than 95 percent, and color was totally removed in all experimented conditions.
From the stand point of turbidity, color, and COD removal both alum and ferric chloride showed the same results, however, ferric chloride dose was lower than alum. In case of turbidity removal alum showed higher removal efficiency, while for COD reduction upon the conditions, e.g. seasonal variation, alum and ferric chloride performance was not the same and was varied accordingly.

Cream, a rich dairy product, with a neutral PH and low preservation time is a suitable medium for microbial growth. Salmonella is one of the most important pathogens in causing food poisoning and human gastroenteritis. This study aimed at investigating the quality of traditional cream for the bacterial contamination.

In this cross-sectional study, 196 non-pasteurized cream samples were collected from 5 regions of Hamedan, Iran. After dilution in phosphate buffer and serial dilution preparation, Salmonella was transferred to Rappaport-Vassiliadis (RV) enrichment medium according to CDC guidelines. After 24 h incubation at 37 ° C, a loop was inoculated in MacConkey and Hektoen Enteric (HE) Agar. The suspected colony phenotype was examined and their identification confirmed by API-20 E.

The samples (29%) were contaminated with at least one kind of bacteria, Salmonella Spp (4.59%) and Yersinia Spp (2.55%). The other bacteria like Escherichia, Enterobacter, Klebsiella, and Citrobacter were also isolated. Nine samples were contaminated with two kinds of bacteria.

The presence of bacteria such as Salmonella and Yersinia in unpasteurized cream indicates that more quality control needs to be applied to the traditional crème produced in the city by health control office of food products.

Even if a small number of poultry carcasses contaminate with pathogenic food bacteria, the chance of spreading the infection in the chillers of poultry slaughterhouse, resulting in contamination of other carcasses also have been observed. In this study, Coliform bacteria, Salmonella and the Psychrophiles in the two different poultry slaughterhouse of Yazd province have been investigated. Sampling from each line (slaughter and chiller) in two stages (before and after removal from the line) three times (the beginning, middle and the end of the slaughter ing) was carried out. Five Chicken carcasses were randomly selected, numbered and sampled both before entering the line and after exiting the line while rinsed using peptone Water. A total of 120 samples were sent to the laboratory for culturing and microbial counting. Significant differences were detected between chiller and slaughter line. The population of coliforms in the slaughter line was significantly more than the chillers (p<0.01). In the case of salmonella the only difference was in the amount of bacteria between two slaughterhouse being significantly lower in slaughter house two (P <0.05). The results showed no significant differences among different treatments in respect to psychrophile bacteria.In general, it can be said that secondary contamination in the slaughter line along with gradual increase in temperature of the chiller can increase bacterial load of both coliforms and salmonella but it will not affect the amount of psychrophile bacteria. Due to some differences between the studied slaughterhouses, microbial load of coli form and salmonella can be acheived by improving the management and installation of appropriate aquipments in the evisceration line.