Showing 11 results for Salmonella
R Nosoohian, M Yavari, A Ajami, M Sadegh,
Volume 1, Issue 1 (4-2007)
Abstract
Abstract Background and objectives :Epidemic dysentery, which can be caused by different organisms, is a major problem in developing countries. The cause variability and drug resistance make the treatment difficult. This study was carried out to determine the prevalence and antimicrobial susceptibility patterns of Shigella in Isfahan reference laboratory. Materials and Methods: In this descriptive study,200 stool samples referred to Isfahan Reference Laboratory were examined to detect possible microorganisms and their antibiotic sensitivity. Results:The Shigella and Salmonella infections rates were 17% and 0.5%. Shigella which is the most frequent cultured organism(97% of bacterial samples) includes: 79% Sd1, 15% Shigella Flexneri and 5% Shigella Sunnei. None of the samples was infected by Ecoli O157H7 or Entamoeba histolitica. The most effective ntibioticwas Ciprofloxacin (no resistance was seen to this antibiotic). Conclusion: The most important cause of bacterial dysentery in this study was shigellosis (sd1). Antibiotic resistance to ampicillin, Amoxiclav and Cotrimoxasole was quite high. This necessitates avoiding to empirical treatment of dysentery. Keywords: Dysentery, Antibiotic resistance, Salmonella, Shigella, Ecoli
Soltan Dallal. M.m, Rahimi Forushani, A., Sadigh Maroufi, S, Sharifi Yazdi, K,
Volume 5, Issue 2 (10-2011)
Abstract
Abstract Bachground and objectives: Salmonella is one of the most important agents of gastrointestinal infection and diarrhea in our country. Misdiagnosis of these bacteria leads to cure failure. The aim of this study was to make a comparison between PCR and the API-20E and conventional biochemical tests carried out for the identification of Salmonella. Material and Methods: In this study 470 specimens taken from children, with acute gastroenteritis, referred to teaching hospitals called Imam, Shariati and children medical centre. The specimens were transferred to microbiology laboratory in public health school for identification of Salmonella with PCR and API-20E methods. Results: Of 470 specimens, 65(13.8%) are positive for salmonella in hospital laboratory, while 37 (7.9%) for API-20E and 39 (8.3%) for PCR are positive. The results of antibiotic sensitivity tests on 39 salmonella isolated from diarrhea specimens show that 73.3% of them are resistance to at least one of the sixteen antibiotics tested. Conclusion: Based on the the results, there is significant difference (P<0.05) between conventional method, API-20E and PCR Key words: Salmonella, conventional identification, molecular identification
Mm Soltan Dallal, A Rahimi Forushani, K Sharifi Yazdi, B Nikmanesh, A Rastegar Lari,, A Aminharati,
Volume 7, Issue 1 (4-2013)
Abstract
Abstract
Background and Objectives: gasterointertidis is one of the most common forms of Salmonellosis, which is a worldwide problem. The invasive characteristic of intestinal bacteria is one of their pathogenicity Mechanisms , which can be easily investigated by cell culture technique. In this study ,the invasive characteristic of some Salmonella serogroup were investigated by using HEP-2 cell.
Methods and Material: The rectals soap were prepared from 280 diarrhea patients referred to Imam Khomeyni and children medical centres , 140 with bloody diarrhea and 140 with watery diarrhea as a comparison group. The rectal soap was taken before patients taking any antibiotics, and 140 rectal specimens were taken from healthy people as a control group. All the samples were inoculated in differential and selective media, like Hektoen enteric agar and Xylose lysine deoxycholate (XLD) agar .After incubation at 37C for 24 hours, the colonies were examined and identified by conventional biochemical and serological tests. Using HEP-2, cellular invasion characteristic of Salmonella serogroups was assessed. Moreover, the antibiotic resistance patterns were performed according to Clinical and Laboratory Standards Institute (CLSI).
Results: Of all tested samples, 35(8.3%) are Salmonella strains. The frequency of Salmonella is reported for bloody diarrhea (5.2%) , watery diarrhea ( 1.7%) and control group( 1.4%) .The most abundant serogroups with invasive characteristic, using HEP-2 cell culture, are serogroup B ( 62.9%) and D (17.2%).
Conclusion
The results obtained in this study show that the majority of Salmonella isolates are without invasive characteristic.
Key words: Salmonella, Diarrhea, Cell invasion, Cell culture
K Dorri, N Namdar, V Hemayatkhahjahromi,
Volume 7, Issue 1 (4-2013)
Abstract
Abstract
Background and objective: The effects of lactobacillus Species and their metabolites on dairy products were proved as probiotics on pathogenic bacteria. The aim of this study was to isolate the lactobacillus from dairy product (Yogurt, cheese, milk and whey …) and to determine the antimicrobial activity against some pathogenic bacteria (Salmonella typhimurium, E.coli, Helicobacter pylori.
Material and methods: Samples of dairy products were collected and were serially diluted in peptone medium. To isolate lactobacillus, diluted sample were plated on MRS Agar medium and incubated at 37ºc for 48-72h in anaerobic condition. Identification of the lactobacilli was performed according to their morphological, cultural, physiological and biochemical characteristics. The inhibitory effect of isolated lactobacillus strains were performed against pathogenic bacteria by Agar Well Diffusion Assay and Disc method.
Results: of 50 samples of isolated Lactobacillus from dairy products (including 11 identified Lactobacillus), 19 samples have inhibitory effect on pathogenic bacteria such as Salmonella typhimurium, Escherichia coli and Helicobacter pylori. The most identified strains areLactobacillusbulgaris, Lactobacillus Salivarius and Lactobacillus delbrueki.
Conclusion: According to this study, some lactobacillus strains isolated from dairy products are useful in the management of diarrhea and other gastrointestinal diseases, and the use of these strains can be useful for prevention and treatment.
Keywords:Lactobacillus, Dairyproducts, SalmonellaTyphimurium, E.coli, Helicobacter pylori
R Morshed,
Volume 8, Issue 1 (4-2014)
Abstract
Abstract
Background and Objective: Salmonellosis is one of the most important food-borne bacterial zoonotic diseases worldwide, and poultry and its products are the major sources for salmonella transmission to human. Isolation of Salmonellaenterica from poultry needs bacteriologic enrichment and selected cultures of fecal samples. In this study, different culture methods for the isolation of salmonella from fecal samples were compared.
Material and Methods: Forty- five positive samples from infected farms and 45 negative samples from normal farms were processed using enrichment media including tetrathionate broth, selenite cistine and Rappaport-Vassiliadis. Then the samples were incubated in selective cultures, and after 24 h, their results were compared with standard method.
Results: Specificity of all methods for salmonella isolation was 100%, and salmonella was not isolated from the negative samples. The highest susceptibility was related to the method in which the sample first in Selenite cistine and later in Rappaport-Vassiliadis was enriched (100%). Enrichment in Rappaport-Vassiliadis could isolate 41 salmonella from 45 positive samples (91%) while the result of enrichment in tetrathionate was 6 isolates (13.3%).
Conclusion: This study shows that enrichment in selenite cistine and then in Rappaport-Vassiliadis is currently the best method for isolating salmonella from fecal samples of poultry.
Key words: Salmonella Bacteriologic Culture Diagnosis Isolation Enrichment Poultry
Ghanadan, M, Akbari, N, Soltan Dallal, Mm,
Volume 8, Issue 5 (1-2015)
Abstract
Abstract Background and Objective: 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. Material and Methods: 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. Results: 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. Conclusion: 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. Keywords: Cream, Salmonella SPP, Coliform, Yersinia Enterocolitica, Hamedan
Monadi, M, Kargar, M, Naghiha, A, Najafi, A, Mohammadi, R,
Volume 9, Issue 1 (4-2015)
Abstract
Abstract
Background and Objective: Salmonellosis is the most common type of food poisoning in developed and developing countries that is caused by Salmonella serotype. Hence, we aimed to identify the Salmonella serovars in eggs obtained from Kohgiluyeh and Boyerahmad province and to evaluate antibiotic resistance of the isolated strains.
Material and Methods: In this study, 210 eggs were collected from Kohgiluyeh and Boyerahmad Province. The bacteria were isolated and identified using biochemical tests. After extraction of genomic DNA, Salmonella gender, Salmonella enteritidis and Salmonella typhimurium were investigated by invA, fliC and sefA primers, respectively, using Multiplex PCR method.
Results: Of 210, 14 (6.66%) were contaminated with Salmonella. Of these, 12 (5.71%) were Salmonella typhimurium and 2 (0.95%) were related to Salmonella spp. None of the samples were contaminated with Salmonella enteritidis. The highest resistance was related to penicillin (100%) and neomycin (78.57%).
Conclusion: Salmonella typhimurium is the predominant serovar causing contamination in the eggs of this Province. Given the wide spread of antibiotic resistance in different serotypes of Salmonella, we recommend avoiding of indiscriminate use of antibiotics in livestock and poultry.
Keywords: Salmonella, Drug Resistance, Antibiotic, Multiplex PCR, Kohgiluyeh and Boyerahmad
Ania Ahani Azari , Taghi Zahraei Salehi , Bahar Nayeri Fasaei ,
Volume 10, Issue 6 (11-2016)
Abstract
ABSTRACT
Background and Objective: In this study, we compared the susceptibility of Salmonella typhimurium phoP mutant and its parent to stress conditions that the pathogen may encounter in a host.
Methods: For this purpose, we used the phoP deletion mutant constructed in our previous study. In order to test the in vitro susceptibility of the mutant to stress factors, the effect of acidic pH, heat, bile salts and polymyxin on growth of the mutant was examined. Then, minimum inhibitory concentration and minimum bactericidal concentration of bile salts and polymyxin were determined. Salmonella typhimurium 14028 was used as the parent strain.
Results: The mutant was highly susceptible to bile salts and polymyxin in comparison with the parent strain, but no difference was observed in their susceptibility to acid and heat.
Conclusion: This study confirms the role of the phoP in resistance of Salmonella to polymyxin and bile salts. Mutation in the phoP leads to susceptibility of the mutant to bile and cationic antimicrobial peptides.
Keywords: In vitro, Mutant, Salmonella typhimurium, Disease Susceptibility.
Somaieh Sabzali, Majid Bouzari,
Volume 14, Issue 4 (7-2020)
Abstract
Background and objectives: are divided into two species: Salmonella enterica and Salmonella Salmonella bongori. S. enterica has more than 2,500 serotypes. Serovars of S. enterica such as Typhimurium, Enteritidis, Paratyphi B, Paratyphi A and Newport are associated with human infections. Approximately 75% of human Salmonella infections have been associated with contaminated food such as eggs, chicken, beef, pork, dairy products, fruits and vegetables. The aim of this study was to determine the frequency of Salmonella strains isolated from various food sources in Isfahan, Iran.
Methods: Forty Salmonella strains were isolated from 450 suspected cases referred to the veterinary reference laboratory of Isfahan Province. The isolates were identified by differential and serotyping tests and then confirmed by PCR. A phylogenic tree was constructed with 34 sequences by neighbor-joining method using the MEGA7 software (version 7.1).
Results: Overall, 10 Salmonella serovars were isolated from 32 chicken meat, three beef and five egg shell samples. S. enterica serovar Ouakum (20%), S. Enteritidis (17.5%) and S. Typhimurium (17.5%) were the most common serovars, while S. enterica serovar Nitra (2.5%) was found as the least prevalent isolate.
Conclusion: In this study, S. Typhimurium species is placed in different clusters along with sequences reported from different parts of the world, indicating that the serovars are circulating all over the world.
Mojtaba Mohammadzadeh Vazifeh , Seyed Masoud Hosseini, Ali Mohammadi, Mahdi Jahanfar , Hadi Maleki ,
Volume 15, Issue 2 (3-2021)
Abstract
Background and objectives: Gouda Cheese is regarded as a high quality and one of the most popular cheeses in the world. The defining characteristics of Gouda cheese are its yellow color, great aroma and taste of caramel sweetness. The cheese should be well chilled before waxing, to get better seal. The seal is very important to prevent contamination with molds and putrefactive bacteria. Cheese wax is made from paraffin with additional microcrystalline to make pliable for better seal. The aim of this study was to investigate antibacterial effects of Gouda cheese wax.
Methods: Gouda cheese wax samples were collected from four different manufacturers in Iran. The total count of coliforms, Escherichia coli, Salmonella, coagulase-positive Staphylococcus and mold and yeast on the samples was determined. The antimicrobial activities of Gouda cheese wax against E. coli, S. aureus, Saccharomyces cerevisiae, Aspergillus brazilissis and Salmonella enterica were investigated by determining minimum bactericidal concentration and minimum inhibitory concentration.
Results: The results indicated that all Gouda cheese wax samples were prepared in accordance with the national standards. In addition, the examined wax samples had no antimicrobial properties against the tested microorganisms.
Conclusions: The wax used in production of Gouda cheese in Iran has no antimicrobial properties.
Farzane Maryam, Poozesh Vahid, Atefe Amirahmadi, Fatemeh Salimi,
Volume 17, Issue 3 (5-2023)
Abstract
Background and objectives: Foodborne pathogens can significantly affect the public health and cause medical, social, and economic burden. Listeria monocytogenes, Salmonella enterica, and Yersinia enterocolitica are important foodborne pathogens that can cause various diseases. Plant-derived compounds are promising bioactive substances with inhibitory effects against bacteria. Perovskia abrotanoides Kar. is a medical plant with broad therapeutic activities. In the present study, we aimed to investigate the inhibitory effects of P. abrotanoides extracts against some foodborne pathogens.
Methods: Flowering branches of P. abrotanoides were collected in 2018 and 2019 from three different habitats in the eastern Alborz Mountains, Iran. The antimicrobial activity of the extracts was evaluated using the agar well diffusion test. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts were determined against L. monocytogenes, S. enterica, and Y. enterocolitica. In addition, the antioxidant activity of the extracts was investigated by the DPPH test.
Results: The lowest MIC (200 µg/ml) and MBC (400 µg/ml) values against Y. enterocolitica were related to the ethyl acetate extract of plants collected from habitat 1 in 2019. The lowest MIC (50 µg/ml) and MBC (400 µg/ml) values against L. monocytogenes were related to the dichloromethane extract of plants collected from habitat 1 in 2019. All extracts showed antioxidant properties. Results of one-way ANOVA indicated that the DPPH scavenging activity of extracts from plants collected in 2019 was greater than that of those collected in 2018. In most cases, the methanol and ethyl acetate extracts showed more radical scavenging potential.
Conclusion: It seems that P. abrotanoides is a rich source of antimicrobial and antioxidant compounds with great potential for use in the pharmaceutical and food industries.
