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The investigation of microbial flora in dairy factories and the role of environmental factors are very important. This study was to determine the microbial air contamination in various parts of dairy factories in Shahrekord. In this study sampling was done by using sedimentation method. Microbial analysis included counting total aerobic bacteria, staphylococci, bacillus, yeasts, and molds. In each sampling series the plates containing the selective medium, for 1hour, were placed 1meter away from wall and in the height of 1meter from ground in different parts, then the samples were transferred to laboratory and have been kept in 37^oC in incubator for 48hours. After counting the colonies, specific biochemical tests were used for determining isolated bacteria identity. For evaluating of fungal the Potato dextrose agar mediums containing choloramphenicol were used. The gender of grown fungal was determined by using routine laboratory methods including the teased mount and slide culture technique. The results show that the total bacteria number in air ,Among the total isolated colonies, the contamination ratio to gram positive cocci was 44%, gram positive bacilli was 53.1%, gram negative bacilli was 2.7%, and gram negative cocci was 0.57%, Among the total isolated bacteria the most bacterial type was related to Staphylococcus aureus, Bacillus cereus, and Escherichila coli respectively. Also, the results of counting fungi numbers in air showed that ,Among the total 313 various isolated fungal colonies, yeasts 60/3%, Trichosporon14/6%, Paecilomyces7/6 %, Geotrichum5/7%,  Madurella5/7%, Cladosporium2/5%, Aspergillus2/2%, Monillia1% and Rhizopus1% were investigate. According to the suggested air microbial contamination standard amount by America Public Health Association, the results of this study show that the air of different parts of factories have high contamination and the possibility of transfer of contamination to products of these factories is high.  

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Quantitative detection of drug residues in animal food stuffs is very important. Excessive use of veterinarian veterinarians, like antibiotics are a serious threat to consumers, due to the residence of livestock products such as meat, milk, eggs. Rapid detection of antibiotics is essential by using an efficient, fast, affordable, and specific tool for risk reduction and food safety control. In the present study, an aptasensor based on pencil graphite electrode modified with nanomaterial including grapheme and gold, for rapid detection of tetracycline antibiotic was developed in milk samples. Cycle voltammetry and differential pulse voltammetry (DPV) techniques were used for response evaluation of aptasensor. In order to modification the graphite pencil electrode, the scanrate (40 mV/s) and the number of cycles (10) and immobilization time of graphene (90 min) were optimized. Under optimum conditions, using differential pulse voltammetry technique was found to increase linearly in the range of 1 × 10^-12 to 1 × 10^-5 M, with increasing concentration (R² = 0.985). The detection limit of the aptasensor was found to be 1.4× 10^-13 M. A review of functional characteristics including repeatability, reproducibility, satability, and selectivity suggests acceptable performance for aptasensor. Overall, the fabricated aptasensor has efficiency required to detect tetracycline in milk samples.

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Objective and aims: Milk is an important nutritional food and it fully satisfies the nutritional needs of humans for up to 6 months. Due to the presence of nutrients, milk is a very suitable medium for the growth of a variety of bacteria. Hence some people with the addition of some materials were tried to avoid milk deterioration. The common adulterations in raw milk are the addition of neutralizing agents, water, salt, detergent, hydrogen peroxide, formalin, and others.
Materials and Methods: In this study, a total of 120 milk samples were collected from milk collection centers of Mazandaran province. Parameters such as acidity, pH, dry matter, density, protein, fat and freezing point were tested. Also, the addition of detergent, formalin, salt, hydrogen peroxide, and sodium bicarbonate were analyzed on the samples.
Results: The results of the experiments showed that there is no significant difference in the amount of acidity, pH, dry matter, density, protein, the fat and freezing point of raw milk between warm and cold seasons (P>0.05). Also, the results revealed that there were some adulterations in cold season in the milk samples including, hydrogen peroxide 1.6%, and detergents 1.6%. But in the warm season, the amount of fraud in raw milk was higher than in the cold season. These frauds included the addition of formalin 1.6%, detergent 3.3%, hydrogen peroxide 3.3% and sodium bicarbonate 11.6%. There was no adulteration of salt and water added in raw milk samples. Overall, there was a significant difference between the incidence of milk adulteration in warm and cold seasons (P<0.05).
Conclusion: The necessity of continual pursuit of importance regarding the inspection and sampling of milk collection and distribution centers and carry out the appropriate tests in order to check frauds aimed to discuss health and complications from taking it to feel.

 

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Vibrio cholerae is one of the important human pathogens that is transmitted through contaminated water and food. In Qom province, due to special weather conditions, diseases caused by Vibrio cholerae are endemic. The aim of this study was the prevalence of Vibrio cholerae in water and vegetables of Qom province and the presence of two virulence genes, hlyA and toxR. During two years (2020-2021), 120 samples of agricultural water (70) and vegetables (50) in Qom province were collected. The samples were cultured on specific media. Suspicious colonies were evaluated by Gram staining and biochemical tests and the serotype Vibrio cholerae was identified by serology test. Finally, Then, the presence of virulence genes was investigated by PCR method and also the antibiotic resistance pattern by disk diffusion method was evaluated in the isolates.  Vibrio cholera bacteria were isolated from 17 samples (16.14%), all of which were Non-O1. The rate of contamination of water and vegetables was 28.14% (10 cases) and 14.00% (7 cases), respectively. In molecular evaluation, the abundance of virulence genes including: toxR (88.32%), rtxA (58.82%), hlyA (47.05%), chxA (5.88%), and 100% of isolates did not have ctxA, ace and tcpA genes. The most antibiotic resistance is related to ampicillin and amoxicillin (34.29%), followed by cefuroxime (17.46%), imipenem (11.76%), and cefoxitin and trimethoprim-sulfamethoxazole (5.88%). The results of this study showed that Vibrio cholerae Non-O1 is present in water and vegetables of Qom province, and as an important source of disease for humans therefore, continuous health monitoring of water and vegetables and proper disinfection of these foods is very important.