Showing 7 results for Salmonella
Mitra Hatefi, Sedigheh Mehrabian, Ashraf Sadat Nouhi, Robab Rafiee Tabatabaee,
Volume 11, Issue 2 (6-2008)
Abstract
Introduction: In this study, antimutagenesis effect of ethanolic extract of propolis by Ames test against two mutagenic substances named azide sodium and potassium permanganate in the presence and the absence of microsomal homogenate of mouse liver (S9) has been investigated. Materials and Methods: In this experimental study at first, different concentrations of ethanolic extract of propolis (0.1-5%) for determining minimum inhibitory concentration (MIC) against tester strains were used. Then by Ames test, antimutagenesis effect was assessed in nontoxic extent. In this test, various strains of Salmonella typhymurium (TA100 and TA97) that contained selective mutation in their operon histidine, were used. Mutant strains (His-) were grown on culture media containing minimum salt and glucose in the presence of mutagen substances above. So only those bacteria that were reversed by mutation (His+) could grow and form colonies on culture media. If antimutagen (EEP) and mutagen substances were gathered, reversed mutation would be reduced and the rate of mutation inhibition could be calculated by means of formula. The differences between the averages of revertants per plate of the sample in relation to the mutagens were analyzed using SPSS software and one-way ANOVA. Results: The resulted MIC values clearly showed that ethanolic extract of propolis at 5% concentration has antibacterial activity against Salmonella typhymurium, but in 0.1-4% concentrations, such effects were not seen. Findings also showed that propolis in such concentrations could neutralize mutagenic effects of those substances in a dose dependent manner. Conclusion: Finally we found that ethanolic extract of propolis that contains different kinds of major and important substances like flavonoids, has good antimutagenic effects and the best concentration for obtaining such effect is in 4% which also was confirmed with microsomal results. The mechanism of antibacterial effect of propolis is complex and it has no analogy to any classic antibiotics, but it should be emphasized that bacterial cell division is inhibited by propolis. Some researchers also argue that propolis could inhibit DNA-dependent RNA polymerase.
Arash Shams, Sedighe Mehrabian, Nor-Amir Mozafari,
Volume 15, Issue 1 (4-2012)
Abstract
Background: Olive oil as a mjor source of fat in diet, besides having a high level of unsaturated fatty acid contains biological components, such as the antioxidant phenolic compounds that can prevent the destructive effect of free radicals and their resulting mutation on cellular structures. The main goal of this study was to investigate the antioxidant and anticancer effects of olive oil through Salmonella typhimurium and microsome.
Materials and Methods: In this study, 16 Iranian olive oil samples and one Spanish sample were used. The determination test of anti-mutagenic potential was based on the method proposed by Ames et al. using mutant strain of Salmonella typhimurium TA100 and a well-known carcinogenic material (sodium azide) which by adding microsome of rat liver (S9), its anticancer effect was examined. Positive and negative controls which respectively contained sodium azide and distilled water were studied. Each test was simultaneously done three times and the percentage of inhibition was determined according to (1-T/M) × 100.
Results: The inhibitory percentage in its highest level in darkness was equal to 63.64% based on the variety of olive oil and in light was equal to 60.70%.
Conclusion: The findings of this study show that the antioxidant and anticancer properties of olive oil decrease with exposure to light
Sedigheh Mehrabian, Ahmad Majd, Ali Kheiri, Parisa Joniubi,
Volume 15, Issue 2 (6-2012)
Abstract
Background: Nowadays, cancer is one of the main causes of death in the world and mutagens cause death in millions of patients. Noticing the side effects of the drugs used to treat cancer, scientists are looking for drugs with fewer side effects and more therapeutic effects. Accordingly, the number of studies in this field is rapidly increasing. This study was done to evaluate the effects of antimutagenesis of aqueous and alcoholic extracts of A. vera leaf gel and latex by Ames test against the mutagenic substance named sodium azid in the presence and absence of microsomal homogenates of rat liver (S9). Materials and Methods:In this experimental study, after preparing different extracts of A. vera gel and latex, the antimutagenic effect of different extracts was assessed by Ames test, within which a mutant strain was grown on a culture containing mutagen substance (NaN3). Antimutagen (A. vera extract) reduced reversed mutation. The difference between the mean number of revertants per plate in relation to the mutagens was analyzed through one-way ANOVA using SPSS software. Results: The results showed that the ethanol extract of latex and aqueous extract of gel had the maximum (91%) and minimum (56%) percentages of inhibition, respectively. Conclusion: This assessment revealed strong antimutagenicity effect for all of the extracts due to the presence of different kinds of antioxidants substances such as various anthraquinones, flavonoids, and vitamins A, C, and E. The maximum inhibition of mutation was observed in ethanol extract of latex. This observation supports the results obtained from the application of microsome mixture as well as those reported by other researchers.
Leila Karami, Ahmad Majd, Sedigheh Mehrabian, Mohammad Nabiuni, Saeed Irian, Mandana Salehi,
Volume 15, Issue 8 (1-2013)
Abstract
Background: Avicennia marina (Forssk.) Vireh. or gray mangrove tree, belonging to the family Avicenniaceae, has long been used as a remedy to treat ulcers and skin diseases. In the present study, the antimutagenic activities of young and mature leaf extracts of Avicennia marina against the mutated bacterium Salmonella typhimurium TA100 were investigated. Materials and Methods: In this experimental study, the bacterial strain was checked for the intended genotypes. Leaves were isolated, dried, and chopped finely using a blender and they were extracted with 80% ethanol or water using a Soxhlet extractor. Metabolic activation was prepared from male rat homogenized liver. Antimutagenic effect of the extracts was tested using Ames test in the presence of a mutagen. Results: The number of mutant colonies decreased in the presence of both ethanol and water extracts with (+S9) and without (-S9) metabolic activation. The ethanolic extract exhibited a higher antimutagenic activity than the water extract. There were no inter-assay differences in the presence and absence of the S9 mixture. The highest (71%) and the lowest (24%) inhibition rates of Salmonella typhimurium TA100 bacterial growth were observed with the ethanolic extract of mature leaves from Bordekhon region and the aqueous extract of young leaves from Assaluyeh region, respectively. Conclusion: The findings of the present study suggest that Avicennia marina (Forssk) Vireh. leaf extracts may contain bioactive compounds that can inhibit mutation, and that biotic and/or abiotic stress might have an effect on the antimutagenic potential of these leaf extracts in the two regions.
Mokhtar Nosrati, Mandana Behbahani,
Volume 18, Issue 4 (7-2015)
Abstract
Background: Medicinal plants are primery source of many drugs to cure different diseases. The genus Prangos, (Umbelliferae family) consists of several medicinal plants that their desirable dffects have been approved. The aim of this study is to investigate the effectiveness of methanol extract in different parts of prangos ferulacea and prangos acaualis on human lymphocytes proliferation and their mutagenicity in salmonella typhimurium TA98.
Materials and Methods: In this experimental study, the plants were collected from different areas of Kurdistan. Then, samples were air dried and powdered and methanol material of plants was extracted. The extracts were diluted to give concentrations of 10, 100, 500, 1000, 1500, 2000, 2500 &mug/ml. Finally, the effects of these extracts on human lymphocytes proliferation and their mutagenecity have been investigated by the MTT and Ames test.
Results: The results showed that different organs extract from both tested plants caused a significant increase in lymphocytes proliferation, specially in concentrations of 500 to 2500 &mug/ml. Of studied excrtacts, the highest and lowest effect on lymphocytes proliferation was obtained in presence of flower and seed, respectively. In total, the levels of proliferation resulted of prangos ferulacea as compared with prangos acaulis were higher. Also, the results of study showed no mutagenicity of studied plant exctracts with considered concentrations.
Conclusion: The findings revealed that both species of prangos can increase immune system function and were used as an safe medicinal plant to cure patients with immune deficiencies and microbial infections.
Hossein Morsali, Golnaz I Asaadi Tehran, Hanieh Asaadi, Sajjad Yazdansetad, Reza Najafpour,
Volume 20, Issue 6 (9-2017)
Abstract
Abstract
Background: Salmonella spp. and Escherichia coli O157:H7 are the most common bacterial foodborne pathogens contaminating food products especially meat. It is essential to detect the pathogens rapidly, specifically, and simultaneously by selection and optimization of suitable reference genes. The present study was conducted to simultaneously detect E. coli O157:H7 and Salmonella spp. in meat products and contamination prevalence assay by using multiplex PCR based on rfbE and invA genes amplification in Zanjan province, northwest of Iran.
Materials and Methods: A total of 74 meat samples were obtained from various regions of Zanjan province, randomly. 25 grams of each meat sample was completely homogenized in 225 ml of Mueller-Hinton broth growth medium and incubated. Bacterial strains were purified and DNA extraction was performed from purified bacterial isolates. Simultaneous amplification of rfbE and invA gene fragments was done with specific primers by optimization of a multiplex PCR. Finally, the sensitivity of the method was evaluated by inoculation of the bacteria to the meat.
Results: Out of 74 meat samples, 6(8%), 4(5.4%), and 2(2.7%) samples were positive for E. coli O157:H7, Salmonella, and both E. coli O157:H7-Salmonella, respectively. Multiplex PCR indicated high sensitivity for simultaneous detection of the pathogens in lowest dilution of the bacteria that had been inoculated to the meat.
Conclusion: In this study, a multiplex PCR was optimized based on Salmonella spp. and E. coli O157:H7 virulence genes for rapid and simultaneous detection of the pathogens with high sensitivity and specificity. Multiplex PCR as a reliable tool for rapid and simultaneous detection of foodborne pathogens to prevent contamination of food products.
Mrs. Mahnaz Ghahramani Til, Mrs. Rezvaneh Sadat Fatemi, Dr. Rahman Shokri, Dr. Mahdi Banitalebi Dehkordi, Dr. Mahdi Paryan,
Volume 25, Issue 4 (9-2022)
Abstract
Introduction: Salmonella infection (salmonellosis) is a common bacterial disease that affects the intestinal tract. Several methods like Multiplex or real-time PCR, ELISA, and Agglutination are used to identify these bacteria. However, normally rapid, cost effective and easy diagnostic methods such as agglutination test is recommended. In Iran, positive control antiserums used in diagnostic kits work based on polyvalent agglutination and are against O and H antigens. The purpose of this research was to produce specific anti-sera against O and H antigens for using in agglutination and ELISA kits.
Methods: New Zealand white rabbits were immunized by intravenous injections of inactivated bacterial O and H antigens adjusted to a cell density equivalent to a turbidity of a McFarland number 3 standard. Serum collection was performed 7 days after the last injection. Collected Antisera were tested with positive human specimens as well as cross-reaction antibodies. Absorption method was used to obtain specific anti-sera against O and H antigens. Produced Anti-O and Anti-H antibodies were mixed with bacterial H and O antigens respectively and incubated for 1 hours in 37˚c. The Mixture was centrifuged and the supernatant was collected. Furthermore, in order to use these antisera in specific kits such as ELISA, Immunofluorescence etc., purification methods like Ammonium sulphate precipitation, tangential Flow Filtration and Chromatography were performed. This study was approved by the ethics committee of Pasteur Institute of Iran (Code: IR.PII.REC.1399.006).
Results: Results of agglutination test before and after adsorption showed cross-reaction before adsorption and no cross-reaction with H and O antigens with monospecific antisera against O and H after adsorption, respectively. Moreover, high quality and quantity of mono-specific antibody was obtained after purification.
Conclusions: Serum-based assays are recommended for the timely diagnosis of the disease since these assays are specific, sensitive, inexpensive, and rapid. Therefore, the produced antiserum in the present research can be used in primary screening of salmonella infections based on agglutination tests which are cost effective and simple. In addition, purified anti-sera can be used in the development of ELISA and Immunofluorescence assays.
