Development and Inter-Laboratory Validation of Diagnostics Panel for Detection of Biothreat Bacteria Based on MOL-PCR Assay.

Early detection of biohazardous bacteria that can be misused as biological weapons is one of the most important measures to prevent the spread and outbreak of biological warfare. For this reason, many instrument platforms need to be introduced into operation in the field of biological warfare detection. Therefore the purpose of this study is to establish a new detection panel for biothreat bacteria (Bacillus anthracis, Yersinia pestis, Francisella tularensis, and Brucella spp.) and confirm it by collaborative validation by using a multiplex oligonucleotide ligation followed by polymerase chain reaction and hybridization to microspheres by MagPix detection platform (MOL-PCR). Appropriate specific sequences in bacterial DNA were selected and tested to assemble the detection panel, and MOLigo probes (short specific oligonucleotides) were designed to show no cross-reactivity when tested between bacteria and to decrease the background signal measurement on the MagPix platform. During testing, sensitivity was assessed for all target bacteria using serially diluted DNA and was determined to be at least 0.5 ng/µL. For use as a diagnostic kit and easier handling, the storage stability of ligation premixes (MOLigo probe mixes) was tested. This highly multiplex method can be used for rapid screening to prevent outbreaks arising from the use of bacterial strains for bioterrorism, because time of analysis take under 4 h.

Effects of selenium feed supplements on functional properties of eggs.

The aim of the present study was to assess the effects of selenium feed supplements on the functional properties of eggs. The hens in experimental groups were fed diets supplemented with 0.2 mg/kg selenium from sodium selenite (Group 1), selenium-enriched yeast (Group 2), synthetic L-selenomethionine (Group 3), or hydroxy analog of selenomethionine (Group 4). The Control Group (Group C) was fed with basal feed without supplementation. The highest values of albumen gel firmness were shown in Group C eggs; differences with all experimental groups were significant (p < 0.001 to p = 0.009). It was ascertained that albumen gel firmness correlated with albumen pH (rs = 0.490; p < 0.001), which was highest in eggs from non-supplemented hens. Group 1 eggs and Group C eggs showed lower albumen foaming capacity (p < 0.001) compared to eggs from other groups. Both albumen foaming capacity and albumen foam stability were higher in Group 2 eggs than in Group C eggs (p < 0.001). The highest yolk foaming capacity was found in Group 2 eggs (p < 0.001). Sponge cakes baked with Group C eggs had a smaller volume than those baked with eggs from Group 2 (p = 0.005), Group 3 (p = 0.004) and Group 4 (p = 0.024). The results of the study confirmed that selenium added to the laying hen feed significantly affected the monitored functional properties of both albumen and yolk. The most distinctive effect of selenium was shown in eggs from the group supplemented with selenium-enriched yeast, for which the results of albumen foam capacity and stability and yolk foaming capacity were the best.

Halal Criteria Versus Conventional Slaughter Technology.

The halal meat industry is today a reality in many regions of the world, including the European Union. The main religious laws in the area of halal meat production were legislated in ancient times and may be unchangeable due to their sanctity perceived by faithful Muslims, while the modern technology used in the meat industry is constantly evolving and being updated. The objective of this study is to highlight the points of controversy between the principles of halal and the technological means currently used in the meat industry. Modern slaughter practices, including animal fasting prior to slaughter, animal body position, the location of the incision during slaughter, stunning and mechanical slaughter, are reviewed. The purpose of preslaughter feed availability according to halal criteria could be to ensure greater welfare for animals, though feed withdrawal is necessary today. Although there is no clear unified opinion among the Islamic sects, reversible stunning of animals is generally accepted. A neck cut at a higher position than the conventional low cut in cattle may reduce the compromise in welfare (the onset of unconsciousness), minimise false aneurysm and be compatible with halal criteria. This study may contribute towards consideration being given to technology that is not in conflict with the religious legislation, while at the same time meeting the requirements of the modern meat industry.

Survival of Mycobacterium avium subsp. paratuberculosis in raw fermented sausages during production and storage.

Mycobacterium avium subsp. paratuberculosis (MAP), the etiological agent of paratuberculosis, is considered to be a potential zoonotic pathogen and meat is one of the sources of MAP exposure for humans. MAP has been shown to be relatively resistant to different food processing methods, but there is a lack of information about the effects of ripening and fermentation processes on MAP survival in meat. Our results demonstrate that a short ripening process during teewurst production did not reduce MAP counts and viable mycobacteria were detected even during 4 weeks of storage. Although no viable MAP was recovered during the dry fermented sausage production process, there was no reduction in MAP count detected by real time PCR during production and storage of both sausages. Although the impact of foodborne exposure to viable MAP and/or mycobacterial components has not yet been clearly determined, the consumption of raw fermented meat products may be considered as a possible route of MAP transmission to humans.

The Quality of DNA Isolated from Processed Food and Feed via Different Extraction Procedures.

The extraction of DNA is a critical step for species identification by PCR analysis in processed food and feed products. In this study, eight DNA extraction procedures were compared-DNeasy Blood and Tissue Kit, DNeasy mericon Food Kit, chemagic DNA Tissue 10 Kit, Food DNA Isolation Kit, UltraPrep Genomic DNA Food Mini Prep Kit, High Pure PCR Template Preparation Kit, phenol-chloroform extraction, and NucleoSpin Food-Using self-prepared samples from both raw and heat-processed and/or mechanically treated muscles and different types of meat products and pet food (pork, beef, and chicken). The yield, purity, and suitability of DNA for PCR amplification was evaluated. Additionally, comparisons between the effectiveness of various extraction methods were made with regard to price, and labor- and time-intensiveness. It was found that the DNeasy mericon Food Kit was the optimal choice for the extraction of DNA from raw muscle, heat-treated muscle, and homemade meat products from multiple and single species.

Evidence for a primate origin of zoonotic Helicobacter suis colonizing domesticated pigs.

Helicobacter suis is the second most prevalent Helicobacter species in the stomach of humans suffering from gastric disease. This bacterium mainly inhabits the stomach of domesticated pigs, in which it causes gastric disease, but it appears to be absent in wild boars. Interestingly, it also colonizes the stomach of asymptomatic rhesus and cynomolgus monkeys. The origin of modern human-, pig- or non-human primate-associated H. suis strains in these respective host populations was hitherto unknown. Here we show that H. suis in pigs possibly originates from non-human primates. Our data suggest that a host jump from macaques to pigs happened between 100 000 and 15 000 years ago and that pig domestication has had a significant impact on the spread of H. suis in the pig population, from where this pathogen occasionally infects humans. Thus, in contrast to our expectations, H. suis appears to have evolved in its main host in a completely different way than its close relative Helicobacter pylori in humans.

Combined antimicrobial effect of oregano essential oil and caprylic acid in minced beef.

Oregano essential oil (OEO) and caprylic acid (CA) are highly aromatic natural antimicrobials with limited individual application in food. We proved their combined additive effect when used in meat. Application of 0.5% CA and 0.2% OEO (v/w) with 0.1% of citric acid in vacuum packed minced beef inoculated with Listeria monocytogenes at a concentration of 5 log cells/g reduced counts of lactic acid bacteria by 1.5 log CFU/g and counts of psychrotrophic bacteria and L. monocytogenes by more than 2.5 log CFU/g at the end of storage at 3°C for 10 days. In sensory evaluation the samples with OEO showed during the whole experiment statistically better scores than control, whereas the samples treated with CA showed worse colour attributes.