Effect of essential oils on survival of salmonella spp. in pork packaged in vacuum and modified atmosphere

I pored uloženih napora i dostignuća koja su ostvarena u prehrambenoj industriji na polju higijene klanja i proizvodne prakse, bakterije uzročnici bolesti prenosivih hranom u koje spada i Salmonella spp. kao jedan od najčešćih patogenih bakterija izolovanih iz mesa, i dalje uzrokuju milione slučajeva oboljenja godišnje na globalnom nivou, predstavljajući ne samo zdravstveni već i ekonomski problem, kako u razvijenim zemljama tako i zemljama u razvoju. Salmonella Enteritidis i Salmonella Typhimurium su serotipovi koji najčešće izazivaju salmonelozu ljudi, međutim sve se češće prijavljuju sliučajevi salmoneloze uzrokovane manje poznatim serotipovima, što naglašava potrebu za njihovom kontrolom. Iako se jaja i meso živine i dalje smatraju glavnim izvorom Salmonella spp., salmoneloza uzrokovana konzumiranjem kontaminiranog svinjskog mesa i proizvoda od svinjskog mesa je u porastu. Industrija mesa se suoči sa novim trendom organske proizvodnje, gde nema mesta za primenu do sada korišćenih hemijskih konzervanasa, od kojih neki ispoljavaju kancerogene i toksične osobine ili dovode do pojava alergija. Etarska ulja su biljni ekstrakti koji se izučavaju pre svega zbog antibakterijskih i antioksidativnih osobina ali i mogućnosti da se koriste kao zamena za sintetičke aditive u prehrambenoj industriji. Primena etarskih ulja može da smanji incidenciju bolesti prenosivih hranom, da produži održivost namirnica i odloži lipidnu oksidaciju. Etarsko ulje timijana i origana jedni su od deset najčešće korišćenih etarskih ulja za primenu u hrani. Cilj istraživanja u okviru ove doktorske disertacije bio je ispitivanje različitih načina pakovanja (vakuum i modifikovana atmosfera) i antimikrobnog efekta različitih koncentracija etarskih ulja origana i timijana (0,3%, 0,6% i 0,9%), na Salmonella spp. i mikrobiološki status mesa, kao i ispitivanje antioksidativnih osobina pomenutih etarskih ulja i njihovog efekta na oksidativne promene lipidne frakcije, fizičko hemijske osobine i prihvatljivost mlevenog svinjskog mesa. Kao sirovina za ispitivanje korišćeno je mleveno meso mišića buta svinja meleza Jorkšira x Landrasa. Na početku eksperimenta ispitan je hemijski sastav etarskih ulja (GC-MS), antioksidanti potencijal etarskih ulja (DPPH test, kapacitet neutralizacije •OH i NO• radikala FRAP test, lipidna peroksidacija) i minimalna inhibitorna koncentracija etarskih ulja timijana i origana, ali i aktivnih principa, eugenola, timola, karvakrola i cinamaldehida (mikrodiluciona metoda) potrebna za inhibiciju šest serovarijeteta Salmonella spp. (S. Enteritidis, S. Typhimurium, S. Infantis, S. Montevideo, S. Senftenberg, S. Givae) i koktel serovarijeteta odabranog za kontaminaciju mesa (S. Enteritidis, S. Typhimurium, S. Infantis, S. Montevideo)...Despite efforts and improvements in slaughter hygiene and food production techniques in the food industry, foodborne pathogens including Salmonella spp as one of the most often pathogen found in meat, still cause millions of episodes of illness annually worldwide, presenting not only health but also an economic problem in both developed and developing countries. Salmonella Enteritidis and Salmonella Typhimurium are serotypes mainly reported as causes of human salmonellosis, but outbreaks of salmonellosis caused by a rarer subspecies of Salmonella are increasing, which is why their control is needed. Eggs and poultry meat are still recognized as main sources of Salmonella infection in humans but salmonellosis caused by consuming contaminated pork meat and derived products are increasing. Moreover, the meat industry is challenged by the new trend of producing all-natural food, where is no place for artificial preservatives which may have some carcinogenic and toxic properties or may cause food allergies or sensitivities. Essential oils (EOs) are plants derived which gained attention mainly due to its antibacterial and antioxidative properties, and potential to be used as a replace for synthetic additives in the food industry. EOs can reduce the incidence of food-borne diseases, extend shelf-life and retard lipid oxidation. Thyme and oregano EO are one of the top ten EOs used as a preservative for food purposes. The aim of this PhD thesis was to evaluate the effect of different packaging conditions (vacuum and modified atmosphere) and different concentrations (0.3%, 0.6% and 0.9%) of thyme and oregano essential oils on survival of Salmonella spp., microbiological status of pork meat, as well as antioxidative properties if essential oils and their effect on lipid oxidation in meat, physicochemical parameters and organoleptic acceptability of meat. Meat used in present study was obtained from pork muscles from legs of different animals, crossbreeds Yorkshire x Landrace and minced in a grinder with 4 mm perforations in the grinding plates. At the beginning of the experiment chemical composition of EOs was determined (GC-MS analysis), as well as antioxidative capacity of EOs (DPPH test, nitric oxide and hydroxyl-radical scavenger capacity, FRAP assay, lipid peroxidation) and minimal inhibitory concentration (MIC) of EOs and active compounds e.g. thymol, carvacrol, eugenol and cinnamaldehyde (microdilution method) needed to inhibit the grow of six serotypes of Salmonella spp. (S. Enteritidis, S. Typhimurium, S. Infantis, S. Montevideo, S. Senftenberg, S. Givae) and the four-strain cocktail of Salmonella chosen to be used in meat contamination (S. Enteritidis, S. Typhimurium, S. Infantis, S. Montevideo)..

Polyphenol-Rich Aronia melanocarpa Juice Consumption Affects LINE-1 DNA Methylation in Peripheral Blood Leukocytes in Dyslipidemic Women

Cardiovascular disease (CVD) is associated with alterations in DNA methylation and polyunsaturated fatty acid (PUFA) profile, both modulated by dietary polyphenols. The present parallel, placebo-controlled study (part of the original clinical study registered as NCT02800967 at www.clinicaltrials.gov) aimed to determine the impact of 4-week daily consumption of polyphenol-rich Aronia melanocarpa juice (AMJ) treatment on Long Interspersed Nucleotide Element-1 (LINE-1) methylation in peripheral blood leukocytes and on plasma PUFAs, in subjects (n = 54, age range of 40.2 ± 6.7 years) at moderate CVD risk, including an increased body mass index, central obesity, high normal blood pressure, and/or dyslipidemia. The goal was also to examine whether factors known to affect DNA methylation (folate intake levels, MTHFR C677T gene variant, anthropometric and metabolic parameters) modulated the LINE-1 methylation levels upon the consumption of polyphenol-rich aronia juice. Experimental analysis of LINE-1 methylation was done by MethyLight method. MTHFR C677T genotypes were determined by the polymerase chain reaction–restriction fragment length polymorphism method, and folate intake was assessed by processing the data from the food frequency questionnaire. PUFAs were measured by gas–liquid chromatography, and serum lipid profile was determined by using Roche Diagnostics kits. The statistical analyses were performed using Statistica software package. In the comparison after vs. before the treatment period, in dyslipidemic women (n = 22), we observed significant decreases in LINE-1 methylation levels (97.54 ± 1.50 vs. 98.39 ± 0.86%, respectively; P = 0.01) and arachidonic acid/eicosapentaenoic acid ratio [29.17 ± 15.21 vs. 38.42 (25.96–89.58), respectively; P = 0.02]. The change (after vs. before treatment) in LINE-1 methylation directly correlated with the presence of MTHFR 677T allele, average daily folate intake, and the change in serum low-density lipoprotein cholesterol but inversely correlated with the change in serum triacylglycerols (R = 0.72, R2 = 0.52, adjusted R2 = 0.36, P = 0.03). The current results imply potential cardioprotective effects of habitual polyphenol-rich aronia juice consumption achieved through the modifications of DNA methylation pattern and PUFAs in subjects at CVD risk, which should be further confirmed. Hence, the precision nutrition-driven modulations of both DNA methylation and PUFA profile may become targets for new approaches in the prevention of CVD

Development of Novel Approaches for Tumour Therapy based on Nanostructured Materials - MagBioVin Project

Research advancements and opportunities by the FP7-ERA Chairs project MagBioVin are spotlighted.[1] Topic of the project is the design of different novel magnetic nanoarchitectures (e.g. bimagnetic and polymeric core-shell systems, nanoparticles embedded in mesoporous silica structures, and radiolabeled nanostructures)[2–4] for application in targeted treatment and diagnostics of cancer. These nanomaterials posses the ability for selective treatment of tumor tissues by the targeting with magnetic field.[5,6] Alternating magnetic field also provides the means for hyperthermia-induced cancer treatment.[7]Attachment of radionuclides to the synthesized nanoparticles is explored for the purpose of imaging and internal radiotherapy.[8,9] Magnetic characteristics of the prepared nanomaterials is done by SQUID magnetometry and Mössbauer spectroscopy. Structural characterization of the investigated nanomaterials is performed by XRD, TEM imaging, DRIFT spectroscopy, and nitrogen sorption analysis. Magnetic hyperthermia effects are monitored by using commercial setup (nB nanoScale Biomagnetics) which includes applicators for cell cultures and small animals. In vitro and in vivo (animal model) applicability of the synthesized nanomaterials regarding toxicity, biodistribution and anticancer efficacy is explored for targeted cancer treatment.1st International Symposium: program and the book of abstracts : March 29-31, 2016; University of Central Lancashire, Preston, U

Culinary preparation and processing of meat with wooden breast myopathy

Recently, poultry meat production and consumption has become increased worldwide. Decades of intensive selection in poultry breeding resulted in fast-growing broilers, improved food conversion, low production costs, and high yield of breast meat, as the most valuable part of the carcass. Some side-effects of intensive production and rapid growth of broilers include the appearance of myopathies in breast muscle. Increasing attention has been paid to the defect known as "wooden breast" (WB) due its incidence and severity of anomaly. WB is characterized by the hardness and pale colour of the fillet. These changes lower the consumer acceptance of the meat, and a pronounced WB is unsuitable for culinary and industrial processing. Different procedures can be used to tenderize the meat and include physical and chemical procedures, often combined in industry. Physical procedures comprise the application of heating, mechanical force, ultrasound, electric stimulation, hydrodynamic shock wave-pressure technology, high pressure processing, and pulsed electric field. Chemical procedures include marinating, exposure to the endogenous enzymes, and the use of exoenzymes. In the future, it is necessary to develop optimal tenderizing techniques or combinations of different tenderizing techniques to achieve better sensory quality and improved nutritional value of WB

Seasonal Prevalence of Shiga Toxin-Producing Escherichia coli on Pork Carcasses for Three Steps of the Harvest Process at Two Commercial Processing Plants in the United States

Shiga toxin-producing Escherichia coli (STEC) is a foodborne pathogen that has a significant impact on public health, with strains possessing the attachment factor intimin referred to as enterohemorrhagic E. coli (EHEC) and associated with life-threatening illnesses. Cattle and beef are considered typical sources of STEC, but their presence in pork products is a growing concern. Therefore, carcasses (n = 1,536) at two U.S. pork processors were sampled once per season at three stages of harvest (poststunning skins, postscald carcasses, and chilled carcasses) and then examined using PCR for Shiga toxin genes (stx), intimin genes (eae), aerobic plate count (APC), and Enterobacteriaceae counts (EBC). The prevalence of stx on skins, postscald, and chilled carcasses was 85.3, 17.5, and 5.4%, respectively, with 82.3, 7.8, and 1.7% of swabs, respectively, having stx and eae present. All stx-positive samples were subjected to culture isolation that resulted in 368 STEC and 46 EHEC isolates. The most frequently identified STEC were serogroups O121, O8, and O91 (63, 6.7, and 6.0% of total STEC, respectively). The most frequently isolated EHEC was serotype O157:H7 (63% of total EHEC). Results showed that scalding significantly reduced (P 75%) cases of severe illnesses caused by STEC and are considered adulterants of beef. However, some STEC outbreaks have been attributed to pork products, although the same E. coli are not considered adulterants in pork because little is known of their prevalence along the pork chain. The significance of the work presented here is that it identifies disease-causing STEC, EHEC, demonstrating that these same organisms are a food safety hazard in pork as well as beef. The results show that most STEC isolated from pork are not likely to cause severe disease in humans and that processes used in pork harvest, such as scalding, offer a significant control point to reduce contamination. The results will assist the pork processing industry and regulatory agencies to optimize interventions to improve the safety of pork products.Supplementary material: [https://vet-erinar.vet.bg.ac.rs/handle/123456789/2030]This is the peer-reviewed version of the following article: Nastasijevic, I.; Schmidt, J. W.; Boskovic, M.; Glisic, M.; Kalchayanand, N.; Shackelford, S. D.; Wheeler, T. L.; Koohmaraie, M.; Bosilevac, J. M. Seasonal Prevalence of Shiga Toxin-Producing Escherichia Coli on Pork Carcasses for Three Steps of the Harvest Process at Two Commercial Processing Plants in the United States. Appl. Environ. Microbiol. 2020, 87 (1). [https://doi.org/10.1128/AEM.01711-20

Supplementary data for article: Nastasijevic, I.; Schmidt, J. W.; Boskovic, M.; Glisic, M.; Kalchayanand, N.; Shackelford, S. D.; Wheeler, T. L.; Koohmaraie, M.; Bosilevac, J. M. Seasonal Prevalence of Shiga Toxin-Producing Escherichia Coli on Pork Carcasses for Three Steps of the Harvest Process at Two Commercial Processing Plants in the United States. Appl. Environ. Microbiol. 2020, 87 (1). https://doi.org/10.1128/AEM.01711-20.

Supplementary material for: [https://doi.org/10.1128/AEM.01711-20]Related to published version: [https://vet-erinar.vet.bg.ac.rs/handle/123456789/2029

Effect of essential oils on survival of salmonella spp. in pork packaged in vacuum and modified atmosphere

I pored uloženih napora i dostignuća koja su ostvarena u prehrambenoj industriji na polju higijene klanja i proizvodne prakse, bakterije uzročnici bolesti prenosivih hranom u koje spada i Salmonella spp. kao jedan od najčešćih patogenih bakterija izolovanih iz mesa, i dalje uzrokuju milione slučajeva oboljenja godišnje na globalnom nivou, predstavljajući ne samo zdravstveni već i ekonomski problem, kako u razvijenim zemljama tako i zemljama u razvoju. Salmonella Enteritidis i Salmonella Typhimurium su serotipovi koji najčešće izazivaju salmonelozu ljudi, međutim sve se češće prijavljuju sliučajevi salmoneloze uzrokovane manje poznatim serotipovima, što naglašava potrebu za njihovom kontrolom. Iako se jaja i meso živine i dalje smatraju glavnim izvorom Salmonella spp., salmoneloza uzrokovana konzumiranjem kontaminiranog svinjskog mesa i proizvoda od svinjskog mesa je u porastu. Industrija mesa se suoči sa novim trendom organske proizvodnje, gde nema mesta za primenu do sada korišćenih hemijskih konzervanasa, od kojih neki ispoljavaju kancerogene i toksične osobine ili dovode do pojava alergija. Etarska ulja su biljni ekstrakti koji se izučavaju pre svega zbog antibakterijskih i antioksidativnih osobina ali i mogućnosti da se koriste kao zamena za sintetičke aditive u prehrambenoj industriji. Primena etarskih ulja može da smanji incidenciju bolesti prenosivih hranom, da produži održivost namirnica i odloži lipidnu oksidaciju. Etarsko ulje timijana i origana jedni su od deset najčešće korišćenih etarskih ulja za primenu u hrani. Cilj istraživanja u okviru ove doktorske disertacije bio je ispitivanje različitih načina pakovanja (vakuum i modifikovana atmosfera) i antimikrobnog efekta različitih koncentracija etarskih ulja origana i timijana (0,3%, 0,6% i 0,9%), na Salmonella spp. i mikrobiološki status mesa, kao i ispitivanje antioksidativnih osobina pomenutih etarskih ulja i njihovog efekta na oksidativne promene lipidne frakcije, fizičko hemijske osobine i prihvatljivost mlevenog svinjskog mesa. Kao sirovina za ispitivanje korišćeno je mleveno meso mišića buta svinja meleza Jorkšira x Landrasa. Na početku eksperimenta ispitan je hemijski sastav etarskih ulja (GC-MS), antioksidanti potencijal etarskih ulja (DPPH test, kapacitet neutralizacije •OH i NO• radikala FRAP test, lipidna peroksidacija) i minimalna inhibitorna koncentracija etarskih ulja timijana i origana, ali i aktivnih principa, eugenola, timola, karvakrola i cinamaldehida (mikrodiluciona metoda) potrebna za inhibiciju šest serovarijeteta Salmonella spp. (S. Enteritidis, S. Typhimurium, S. Infantis, S. Montevideo, S. Senftenberg, S. Givae) i koktel serovarijeteta odabranog za kontaminaciju mesa (S. Enteritidis, S. Typhimurium, S. Infantis, S. Montevideo)...Despite efforts and improvements in slaughter hygiene and food production techniques in the food industry, foodborne pathogens including Salmonella spp as one of the most often pathogen found in meat, still cause millions of episodes of illness annually worldwide, presenting not only health but also an economic problem in both developed and developing countries. Salmonella Enteritidis and Salmonella Typhimurium are serotypes mainly reported as causes of human salmonellosis, but outbreaks of salmonellosis caused by a rarer subspecies of Salmonella are increasing, which is why their control is needed. Eggs and poultry meat are still recognized as main sources of Salmonella infection in humans but salmonellosis caused by consuming contaminated pork meat and derived products are increasing. Moreover, the meat industry is challenged by the new trend of producing all-natural food, where is no place for artificial preservatives which may have some carcinogenic and toxic properties or may cause food allergies or sensitivities. Essential oils (EOs) are plants derived which gained attention mainly due to its antibacterial and antioxidative properties, and potential to be used as a replace for synthetic additives in the food industry. EOs can reduce the incidence of food-borne diseases, extend shelf-life and retard lipid oxidation. Thyme and oregano EO are one of the top ten EOs used as a preservative for food purposes. The aim of this PhD thesis was to evaluate the effect of different packaging conditions (vacuum and modified atmosphere) and different concentrations (0.3%, 0.6% and 0.9%) of thyme and oregano essential oils on survival of Salmonella spp., microbiological status of pork meat, as well as antioxidative properties if essential oils and their effect on lipid oxidation in meat, physicochemical parameters and organoleptic acceptability of meat. Meat used in present study was obtained from pork muscles from legs of different animals, crossbreeds Yorkshire x Landrace and minced in a grinder with 4 mm perforations in the grinding plates. At the beginning of the experiment chemical composition of EOs was determined (GC-MS analysis), as well as antioxidative capacity of EOs (DPPH test, nitric oxide and hydroxyl-radical scavenger capacity, FRAP assay, lipid peroxidation) and minimal inhibitory concentration (MIC) of EOs and active compounds e.g. thymol, carvacrol, eugenol and cinnamaldehyde (microdilution method) needed to inhibit the grow of six serotypes of Salmonella spp. (S. Enteritidis, S. Typhimurium, S. Infantis, S. Montevideo, S. Senftenberg, S. Givae) and the four-strain cocktail of Salmonella chosen to be used in meat contamination (S. Enteritidis, S. Typhimurium, S. Infantis, S. Montevideo)..

Electrical properties of multidoped ceria

Multidoped nanosized ceria powders were prepared by either modified glycine nitrate procedure (MGNP) or self-propagating reaction at room temperature (SPRT). As the dopants to CeO2, trivalent rare earth oxides such as Nd2O3, Sm2O3, Gd2O3, Dy2O3 and Y2O3 were used, with the total molar fraction of 20%. The pressed powder pellets were subjected to the densification by sintering at 1500 degrees C, in an air atmosphere. A single-phase crystalline form was evidenced by X-ray diffractometry for both sintered materials. By means of complex impedance measurements, the conductivity of the sintered samples was determined as a function of temperature. At 700 degrees C, the conductivity amounted to 2.19 x 10(-2) and 1.40 x 10(-2) ohm(-1) cm(-1) for the SPRT and for the MGNP sample, respectively. The corresponding values of activation energies of conductivity amounted to 0.72 (MGNP) and 0.59 (SPRT) eV in the temperature range 550-700 degrees C. (C) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved

Electrical characterization of multidoped ceria ceramics

Ceria ceramics was obtained from multi-doped nanosized ceria powders prepared by both modified glycine nitrate procedure (MGNP) and self-propagating reaction at room temperature (SPRT). Rare earth elements such as Nd, Sm, Gdr, Dy, Y, Yb were used as dopants. The overall mole fraction of dopants was 0.2. One-hour long sintering of powder compacts was performed at 1500 degrees C in oxygen atmosphere. Phase composition, microstructure and ionic conductivity of sintered samples were analysed. Single-phase ceria was detected in all samples. In general, the increase in the number of dopants improved the ionic conductivity. The samples doped simultaneously with five dopants had the highest ionic conductivity, as evidenced by the impedance measurements. At 450 degrees C, the conductivity of sample obtained by MGNP was 3.94 x 10(-3) Omega(-1) cm(-1) whereas the conductivity of sample obtained by SPRT was 2.61 x 10(-3) Omega(-1) cm(-1). The conductivity activation energy for MGNP and SPRT samples was measured to be 0.348 and 0.385 eV, respectively. Finally, the conductivity decreased as the number of dopants increased to six. (C) 2012 Elsevier Ltd and Techna Group S.r.l. All rights reserved

Structural, Electrical and Mechanical Behavior of Thin Copper Coatings Obtained by Various Electrodeposition Processes

Electrochemically deposited copper coatings obtained from sulfate baths on brass substrates in the regime of direct current (DC) with and without an application of ultrasound mixing of electrolytes (DC/US) have been studied. The aim of the research was analysis of the influence of current density, ultrasonic mixing of electrolyte and presence of additives on the electrodeposited coatings, in order to obtain uniform compact coatings suitable for potential application in MEMS devices. Structural, electrical and mechanical behavior of thin copper coatings were investigated using SEM, AFM, four- point probe method and Vickers hardness test.Niš, Serbia, 12-14 Sept. 202