Showing 3 results for Listeria Monocytogenes
Kargar, M, Ebrahimi, E, Amini, J, Najafi, A, Kheirkhah, B,
Volume 8, Issue 4 (1-2015)
Abstract
Abstract
Background and Objective: Listeria monocytogenes is a bacterium transferred by foods and is the agent of many sporadic and epidemic diseases in humans. This study aimed to investigate the prevalence of L. monocytogenes and to determinine their antibiotic resistance profile in red meats.
Material and Methods: this cross-sectional study was performed on 400 red meat samples obtained from industrial slaughterhouses placed in Kerman, Iran. First, the samples were enriched with Simultaneous Enrichment Broth (SEB), and then plated onto Palcam agar and Tryptic Soy Broth Yeast Extract Broth (TSAYE). After identification of the isolates based on biochemical tests and PCR, the isolates were checked for their antibiotic resistance profile using disk Diffusion
Results: of 400 samples, 12 samples (3%) were contaminated with different species of Listeria. Using PCR, hly gene was recognized in eight samples (2%) of L. monocytogenes. Furthermore, there was a significant difference in isolation rate of lamb samples compared to cow ones. While all of the isolates were resistant to clindamycin, amikacin and chloramphenicol, they were sensitive to penicillin.
Conclusion: in spite of low rate of infection in red meat samples in Kerman city, due to high risk of Listeria contamination in red meats, we recommend applying a routine screening to identify this bacterium in our county.
Keywords: Listeria Monocytogenes, Hly Gene, Red Meat, Antibiotic, Kerman
Mohammadpourkanzaq, H, Noroozi, M, Mahmoudi, R, Mohammadpoorasl, A, Zavoshy, R, Asadinadari, M,
Volume 9, Issue 2 (7-2015)
Abstract
Background and Objective: It has been proved that plant essential oils have antimicrobial effects. Stachys Lavandulifolia Vachl is a medicinal plant growing wild in many parts of Iran, and is used as a brewed drink to treat some diseases.
Material and Methods: Aerial parts of Stachys lavandulifolia Vachl at flowering were collected from the Sabalan mountainous area of Ardabil and its essential oil was extracted using a Clevenger-type apparatus. A GC/MS machine was used to identify the chemical constituents of this Essential oil. We used microdilution method to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Essential oil against Listeria Monocytogenes ATCC19118 bacteria.
Result: Sixteen chemical compounds were identified in this essential oil. Of these, γ-terpinene (28%), Phenol (18.16%), Myrcene (17.87%), and α-Pinen (12.7%) were the major ones. The MIC and MBC of the essential oil for Listeria Monocytogenes bacteria were 600 and 2400 ppm, respectively.
Conclusion: Results showed that the Monoterpene and Sesquiterpene groups are the main constituents of this essential oil having bactericidal effects against Listeria Monocytogenes bacteria.
Keywords: Essential Oil, Stachys Lavandulifolia, Listeria Monocytogenes
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.
