Reduction effect of the selected chemical and physical treatments to reduce L. monocytogenes biofilms formed on lettuce and cabbage

As people shift their attention away from unhealthy foods, healthy fresh produce has become popular. However, fresh produce has contributed to many outbreaks of Listeria monocytogenes, which can form a mature biofilm within 24 h. Recent control strategies have proved ineffective in ensuring safe food production. This study focuses on L. monocytogenes biofilms formed on lettuces and cabbages using a viable plate count method and field emission electron microscopy. We investigated the reduction efficacy of treatment with 200 parts per million (ppm) chlorine, 2% each of citric, lactic, and malic acids, 32 Hz ultrasonication (US), 390 mJ/cm² ultraviolet-C (UV-C), or 750 mJ/cm² cold oxygen plasma (COP) on L. monocytogenes biofilms. Following treatment, the quality of the vegetables was analyzed with standard procedures. UV-C and COP showed the best CFU reduction, regardless of the nature of the vegetable surface, while US failed to produce any significant reduction (P > 0.05). Furthermore, chemical treatments reduced count by < 1 log colony forming unit (CFU)/cm² on lettuces, whereas a > 2 log reduction was observed on cabbages. The effect of chemical treatment largely depended on the particular vegetable, while UV-C and COP achieved high reduction regardless of the vegetable, and had no effect on quality. We, therefore, speculate that UV-C and COP show promise in overcoming L. monocytogenes biofilms on food produce.     

A comparative study of physical pretreatments for the extraction of polyphenols and proteins from vine shoots

This work examined the potential of valorization of vine shoots through their polyphenol and protein contents. However the choice of the experimental conditions targeted polyphenol extraction at the expense of proteins for further simplification of the purification process. The intensification of polyphenol and protein extraction by physical treatments (pulsed electric fields (PEF), high-voltage electrical discharges (HVED) and ultrasound (US)) was studied. A significant enhancement of polyphenol extraction was noticed with HVED, PEF and US. However, and for each treatment, the improvement of the extraction process started beyond a specific energetic threshold (HVED (10 kJ/kg), PEF (50 kJ/kg) and US (1010 kJ/kg)). HVED had the highest polyphenol and protein extraction yields with the lowest energetic prerequisite. Extracts of high polyphenol yield (34.5 mg of gallic acid equivalent (GAE) per g of dry matter (DM)) and high purity (89%) were obtained with HVED. Polyphenol and protein diffusion coefficients (m²/s) demonstrated HVED to better enhance the extraction process of those biomolecules. Similarly, the calculation of the electrical conductivity disintegration index, Z, showed the highest tissue damage for HVED and a rising cellular damage with the increased energetic requirement of each treatment.     

Regulatory role of phosphoproteins in the development of bovine small intestine during early life

The small intestine is the primary site of nutrient digestion and absorption, which plays a key role in the survival of neonatal calves. A comprehensive assessment of the phosphoproteomic changes in the small intestine of neonatal calves is unavailable; therefore, we used phosphopeptide enrichment coupled with liquid chromatography-tandem mass spectrometry to investigate the changes in the phosphoproteome profile in the bovine small intestine during the first 36 h of life. Twelve neonatal male calves were assigned to one of the following groups: (1) calves not fed colostrum and slaughtered approximately 2 h postpartum (n = 3), (2) calves fed colostrum at 1 to 2 h and slaughtered 8 h postpartum (n = 3), (3) calves fed 2 colostrum meals (at 1–2 and 10–12 h) and slaughtered 24 h postpartum (n = 3), (4) calves fed 3 colostrum meals (at 1–2, 10–12, and 22–24 h) and slaughtered 36 h postpartum (n = 3). Mid-duodenal, jejunal, and ileal samples of the calves were collected after slaughter. We identified 1,678 phosphoproteins with approximately 3,080 phosphosites, which were mainly Ser (89.9%), Thr (9.8%), and Tyr (0.3%) residues; they belonged to the prodirected (52.9%), basic (20.4%), acidic (16.6%), and Tyr-directed (1.7%) motif categories. The regional differentially expressed phosphoproteins included zonula occludens 2, sorting nexin 12, and protein kinase C, which are mainly associated with developmental processes, intracellular transport, vesicle-mediated transport, and immune system process. They are enriched in the endocytosis, tight junction, insulin signaling, and focal adhesion pathways. The temporal differentially expressed phosphoproteins included occludin, epsin 1, and bridging integrator 1, which were mainly associated with macromolecule metabolic process, cell adhesion, and growth. They were enriched in the spliceosomes, adherens junctions, and tight junctions. The observed changes in the phosphoproteins in the tissues of small intestine suggest the protein phosphorylation plays an important role in nutrient transport and immune response of calves during early life, which needs to be confirmed in a larger study.     

Effect of high-pressure processing on flavonoids,hydroxycinnamic acids,dihydrochalcones and antioxidant activity of apple ‘Golden Delicious’ from different geographical origin

The influence of high-pressure processing (HPP) (400, 500 and 600 MPa at 35 °C for 5 min) on different classes of phenolic compounds and antioxidant activity (AA) of ‘Golden Delicious’ apple from two different growing regions, northeastern of Spain (lowland climate) (S-apples) and north of Italy (mid-mountain climate) (I-apples) was investigated. Total hydroxycinnamic acids, total dihydrochalcones and total flavan-3-ols content were higher in S-apple (untreated and HPP-treated) than in I-apples and total flavonols content was higher in I-apples. HPP affected phenolic compounds and AA depending on the apple geographical origin. 400 MPa/35 °C/5 min increased total flavonols (30%) and maintained total phenolic compounds determined by HPLC (TP-HPLC) in S-apples. The higher increase of TP-HPLC (54%) was achieved when I-apple was treated at 600 MPa. Untreated and HPP-treated I-apples displayed higher AA than S-apples. HPP (400 and 600 MPa) increased AA in I-apple. Positive correlations were found between TP-HPLC and AA (TP-FC, DPPH^·, ABTS^·+ and FRAP) in both Italian and Spanish apples.Industrial relevanceThe apples of cultivar ‘Golden Delicious’ are one of the most consumed fruits in the UE. High-pressure processing (HPP) of these fruits acquires great importance to obtain ingredients and apple functional foods highly demanded by consumers. For this, it is necessary to know the process variables and plant material that favor greater extraction of phenolic compounds and antioxidant activity characteristics. This paper provides useful results to help fruit processor to select the appropriate HPP conditions and the geographical origin of ‘Golden Delicious’ apple to obtain apple-based products with high content on different classes of phenolic compounds with beneficial health effects.     

海参废渣皂苷通过核苷酸结合寡聚化结构域样受体信号通路抵抗环磷酰胺诱导小鼠的免疫抑制

在我国海参是一种具有多种生物活性的传统滋补品。本实验系统性地研究了2.5、5.0、10.0 mg/（kg mb·d）海参废渣皂苷（saponins extracted from sea cucumber residues，SCRSS）对免疫抑制小鼠的调节作用。结果表明，与模型对照组相比，5.0 mg/（kg mb·d）SCRSS使小鼠的体质量、脾脏指数和胸腺指数分别增加了15.3%、23.8%和39.8%；5.0 mg/（kg mb·d）SCRSS也极显著增加了免疫抑制小鼠的吞噬指数（P＜0.01）。此外，与模型对照组相比，各剂量SCRSS均明显地增加了血清中细胞因子的水平，并促进了脾淋巴细胞和腹腔巨噬细胞的增殖活性。其中，中等剂量（5.0 mg/（kg mb·d））SCRSS可以更有效地上调免疫抑制小鼠核苷酸结合寡聚化结构域蛋白1、核苷酸结合寡聚化结构域蛋白2、受体相互作用蛋白-2和核因子-κB的表达。结论：SCRSS具有作为提高免疫力的功能性食品补充剂的潜力。     

Chemical characteristics of spice paprika of different origins

Spice paprika powders from Bulgaria, China, Hungary, Peru, Serbia and Spain were examined to identify the most important differences in their major characteristics and to attempt to find chemical components revealing their origin. Bioactive components, contaminants, aroma and microbiological properties were determined: the amount of carotenoids, tocopherols, ascorbic acid and mycotoxins were determined by HPLC, flavoring properties by GC-MS, lead and cadmium content by atomic absorption spectrophotometry. Carotenoids were found at the highest concentration in samples from Peru and Spain and at the lowest, in Serbian samples. The concentrations of total tocopherol and ascorbic acid were found to be greater in samples from Hungary than from China. Aroma components characteristic to the location were detected in samples from each country of origin. The level of microbiological contamination was acceptable, while contaminants were found in Serbian, Spanish, Peruvian and Chinese samples. The effect of sample origin was also investigated using near infrared spectroscopy.     

Exposure to environmental tobacco smoke during pregnancy and infancy increased the risk of upper respiratory tract infections in infants: A birth cohort study in Wuhan,China

We aimed to evaluate the association of the exposure to environmental tobacco smoke (ETS) during pregnancy and infancy with the risk of upper respiratory tract infections (URTI) in infants based on a Chinese birth cohort study. Among 4178 infants who constituted the final study population, 46.8% experienced URTI in their first year of life. The hazard ratios (HR) and 95% confidence intervals (CI) for the risk of URTI were assessed using Cox regression models. Compared with no ETS during pregnancy, continued ETS during pregnancy was independently associated with a higher risk of URTI (HR: 1.36, 95% CI: 1.13, 1.63) after adjustment for potential confounders and also associated with earlier occurrence of URTI (log-rank P = .002). The association remained consistent across the strata defined according to maternal age, number of siblings, sex, and breastfeeding. Exposure to ETS during infancy was associated with URTI only among infants who were breastfed for less than 12 months (P for interaction < 0.05).Furthermore, infants exposed to ETS during both pregnancy and infancy showed the highest HR of 1.46 (95% CI: 1.16, 1.85) for URTI. Efforts should be made to protect pregnant women and infants from the adverse effects of indoor and outdoor ETS.     

Microbial Diversity of Ground Beef Products in South Korean Retail Market Analyzed by PCR-DGGE and 454 Pyrosequencing

The purpose of this study was to assess the microbial community in ground beef purchased from local stores in the north central area of South Korea. A total of 31 ground beef samples showed 3.77 ± 5.16 × 10⁵ CFU/g on aerobic plate counts, and PCR-based denaturing gradient gel electrophoresis was performed to assess the microbial community, which revealed a diverse profile among the products. Four of these samples were selected for further analyses via 454 pyrosequencing. Pseudomonas was the most frequently identified genus in terms of relative abundance (4.54–73.8%), and other bacteria such as Lactobacillus, Acinetobacter, and Carnobacterium were also identified in the ground beef. The presence of bacteria can affect the spoilage of ground beef products depending on the microbial populations, and understanding these populations may help limit spoilage and/or foodborne illness. This study illustrates the microbial diversity occurring among Korean ground beef products, even within a local region, and provides a molecular approach for potential ground beef microbial quality assessment.