The effect of roasting on the total polyphenols and antioxidant activity of coffee.

The total polyphenolic content and the antioxidant activity have been analyzed in ground beans of green, light, medium and dark roasted coffee by UV-VIS spectrometry. Water coffee extracts showed the highest levels of polyphenols in green and light roasted coffees where the total polyphenolic content (TPC) ranged from 49.19 ± 0.70 to 74.05 ± 0.28 and from 59.79 ± 1.45 to 38.34 ± 1.26 g GAE.kg-1, respectively. In medium roast samples it ranged from 43.90 ± 3.07 to 74.05 ± 0.28g GAE.kg-1 and in dark roast from 37.44 ± 0.63 to 47.41 ± 0.69 g GAE.kg-1. The total antioxidant capacity (TAC) reached the highest values (DPPH inhibition ranging from 69.08 ± 1.33% to 78.55 ± 0.89%) in light roasted coffees. Dark roasted coffees showed both the lowest content of polyphenols as well as the total antioxidant capacity. In case of TPC, statistically significant differences (P˂0.001) have been identified between green coffee and other roasted degrees. Also, dark coffee showed statistically noticeable differences (P˂0.001) in TPC in relation to other roasted stages. Statistically important difference (P˂0.001) has been discovered between the total antioxidant capacity of dark roasted coffee and other roasting levels. The results demonstrated that roasting process affects both the oxidative activity as well as polyphenolic content.

Analysis of data from the rapid alert system for food and feed for the country-of-origin Slovakia for 2002-2020.

The Rapid Alert System for Food and Feed (RASFF) plays a pivotal role in regulating food safety in the European Union by enabling the competent authorities in each Member State to issue warnings for removing unsafe or illegal items from the market. This article undertakes a comprehensive analysis of RASFF data on Slovak food from 2002 to 2020, to investigate the trends in notifications, actions executed, hazard categories, and product categories within the food industry. Our scrutiny of the RASFF data revealed fluctuations in the counts of alerts and information notifications across years, indicating periods of heightened hazard detection and enhanced transparency within the system. Various measures, including destruction, recall, notification, and prohibition, were employed to address these hazards and ensure the safety and compliance of food products. The hazard categories exhibited sporadic patterns, underscoring the necessity for ongoing surveillance and regulatory interventions. Specific product categories, such as dietetic foods, food supplements, and fortified foods, registered higher incidences of hazards in specific years, implying the need for intensified safety precautions. These findings highlight the importance of sustained efforts in maintaining food safety and managing risks within the industry.

The Effect of Heat Treatment on Cow's Milk Protein Profiles.

Milk is a food of high nutritional value processed by heat treatment. Heat treatment of milk is a technological process designed to inhibit the growth of microorganisms and extend the shelf life of products. The heating process directly affects the molecular structure of whey proteins by the process of denaturation. It leads to the formation of a whey protein−casein polymer complex. Based on these facts, milk heat-treatment conditions should be controlled during milk processing. This work focuses on describing the whey protein denaturation process and formation of the complex of whey protein with casein. The effect of heat treatment on individual milk protein fractions alpha-casein (α-cas), beta-casein (ß-cas), kappa-casein (κ-cas), beta-lactoglobulin (ß-lg) and alpha-lactalbumin (α-la) was studied by SDS-PAGE. Formation of the whey protein−casein polymer complex increased significantly (p < 0.05) on increasing the temperature and duration of the heat treatment.

Occurrence of chromosomal aneuploidy in rabbit oocytes and embryos at different developmental stages.

The aim of our study was to analyse chromosomal aneuploidy occurrence in rabbit oocytes and embryos. Chromosomal analysis was done in rabbit oocytes and rabbit preimplantation embryos at 2-, 4- and 8-cell stages derived from in vivo fertilization. For mitotic cycle synchronization at the metaphase stage, 2-, 4- and 8-cell embryos were incubated in k-DMEM medium, supplemented with colcemid (1 microg/ml), for 7, 12 or 13h respectively. Success of metaphase synchronization was at values of 100, 86.1 and 92.2% for 2-, 4- and 8-cell embryos respectively. Recovery rate of analysable metaphase plates was reached at 58.8%, 83.9% and 59.8% for 2-, 4- and 8-cell embryos and 100% for oocytes. Significant difference (p < 0.01) in aneuploidy rate between oocytes (40.7%) and 2-cell embryos (62.5%) was found. These results demonstrate higher efficiency of synchronization of embryo cells at the metaphase stage, what may contribute to elevating the proportion of analysable nuclei.

Combined approach for characterization and quality assessment of rabbit bone marrow-derived mesenchymal stem cells intended for gene banking.

Rabbit mesenchymal stem cells (rMSCs) are promising agents for the preservation of genetic biodiversity in domestic rabbit breeds. However, rMSCs must meet certain requirements to be used for cryopreservation in animal gene banks. Currently, there are numerous discrepancies in the published data regarding the rMSC phenotype, which may complicate efforts to evaluate their purity and suitability for reuse after cryopreservation in gene and tissue banks. We propose a combined approach (flow cytometry, PCR, differentiation and ultrastructure studies) for the characterization and recovery of rMSCs after cryopreservation. Flow cytometric analyses of rMSCs confirmed the expression of CD29, CD44, vimentin, desmin and α-SMA. RT-PCR revealed the expression of other markers at the mRNA level (SSEA-4, CD73, CD90, CD105, CD146 and CD166). rMSCs showed efficient multilineage differentiation into adipo-, chondro- and osteogenic lineages, SOX2 expression (pluripotency) and typical MSC morphology and ultrastructure. The confirmed rMSCs were subsequently used for cryopreservation. Efficient recovery of rMSCs after cryogenic freezing was demonstrated by high cell viability, normal ultrastructure of reseeded rMSCs, high expression of CD29 and CD44 and lineage differentiation capacity. The proposed combined approach could be used for characterization, cryopreservation and recovery of rMSCs as genetic resources for native rabbit breeds.

The effect of hFVIII transgene on the chromosomal aneuploidy rate in rabbits.

The aim of this study was to compare the chromosomal aneuploidy rate between transgenic and non-transgenic rabbits derived from the F4 generation. Chromosomal analysis was carried out on bone marrow samples of New Zealand White transgenic (carrying human factor VIII gene) and non-transgenic rabbits (F4 generation) each having a different genetic background (female no. 1-3-5 line I and female no. 1-9-7 line II). C-metaphase plates were obtained from the bone marrow lymphocytes synchronized by the addition of 0.25 microg/ml colcemide. No significant difference in chromosomal aneuploidy between transgenic (61%) and non-transgenic (51.27%) rabbits of line I was observed. A higher but non-significant aneuploidy rate between transgenic and non-transgenic rabbits was found in line II, on the other hand a significant difference (P<0.05) was observed in diploidy rate. In conclusion, chromosomal aneuploidy rates in this experiment were higher than published previously in other reports.

Different RNA and protein expression of surface markers in rabbit amniotic fluid-derived mesenchymal stem cells.

Over the years, there has been much confusion in defining molecular markers of mesenchymal stem cells (MSCs) for other than human species due to a lack of species-specific antibodies. Therefore, the aim of our study was to define rabbit amniotic fluid-derived mesenchymal stem cells (rAF-MSCs) and to reflect upon the current identification of AF-MSCs by providing a summary of detected surface markers in different species. The expression of rAF-MSC surface markers was analyzed at the protein and mRNA level. Flow cytometry analyses showed that rAF-MSCs were positive for CD29 and CD44, low positive for CD90, but negative for CD73, CD105, and CD166. Interestingly, RT-PCR (reverse transcription-polymerase chain reaction) exposed a discprepancy between transcribed mRNA and protein expression, as the cells expressed mRNA of all MSC markers: CD29, CD44, CD73, CD90, CD105, and CD166. Our results also confirmed the mesenchymal nature of isolated cells by morphology, ultrastructure, and intracellular marker expression profile. In addition, the expression of few pluripotency markers was also detected. We also found that passaging did not affect apoptosis and viability. Similarly, changes in karyotype were not observed during passaging. In conclusion, the provided characteristics may be used as a comprehensive set of criteria to define and characterize rAF-MSCs, required for the identification of these cells in preclinical investigations. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1601-1613, 2017.