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.
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.
