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The beetroot is typically on the table in winter in form of pickles or juice, but for its nutritional values it would deserve more common consumption. Its curative effect in great part is due to the several vitamins, minerals, and compounds with antioxidant activity. But the division of biological active compounds is very different in the parts of the root. Based on our results, we could compare the differences between the morphology and some inner contents (soluble solid content, colour, betacyanin, betaxanthin, and polyphenol contents, antioxidant activity, and some flavonoids) of two beetroot cultivars. The results of the morphological investigations showed that the ‘Cylindre’ cultivar had more favourable crop parameters than the ‘Alto F1’ cultivar. In the ‘Cylindre’ cultivar the polyphenol content and the antioxidant capacity were significantly higher than in the ‘Alto F1’ cultivar. By determination of the betanin contents of the investigated beetroots, our results showed both betacyanin and betaxanthin contents were higher in the ‘Cylindre’ cultivar. The chlorogenic acid, gallic acid, the cumaric acid have been identified based on the peaks of HPLC in the studied beetroot cultivars.
Important differences have been reported in several countries about the level of concern in connection with food additives. In order to better understand the consumer preferences related to foodstuffs containing food additives, five hypotheses were tested with the help of a choice-based conjoint analysis. The study was performed in three European countries (Hungary, Romania, and Spain) having different risk perceptions concerning food additives. Two “model foodstuffs” were involved in the analysis: pre-packed sliced cheese (natural image) and chips (artificial image). For the creation of the conjoint cards, three attributes were selected: “preservatives” (natural/artificial), “packaging gases” (contains/does not contain) and “price” (average based on market data/+10%/+20%). Results were collected via Internet simultaneously and a total of 500 valid questionnaires were received in case of pre-packed cheese and 468 regarding chips. In the analysed countries “preservatives” had an outstanding importance — mainly in Hungary and Romania —, while “packaging gases” got lower importance during the shopping intention. “Natural preservatives” very positively contributed to the choosing of both pre-packed sliced cheese and chips. High level of willingness to pay was not observed, as well as the “price” was less important factor than the additives. Comparison of the data from three countries showed notable differences, which can determine the direction of the product planning and development.
Time consuming and expensive methods have been applied for detection of coffee adulteration based on the literature. In the present work, an optical method (vision system) and the application of an electronic tongue is proposed to reveal the addition of barley in different proportion to coffee in ground and brewed forms. In a range of 1 to 80% (w/w) Robusta coffee was blended with roasted barley. Principal Component Analysis (PCA) accomplished on vision system image data showed a good discrimination of the adulterated samples. The results of Polar Qualification System (PQS) data reduction method revealed even small differences in the right barley content order by point method approach. With Partial Least Squares (PLS) regression the amount of barley in Robusta was predicted with high R2 (0.996) and relatively low RMSEP (∼2%) values in case of vision system data processing. Considering electronic tongue measurements, PCA results showed a good discrimination of samples with higher barley concentration. Misclassification was found in the low concentrated area by Lienar Discriminant Analgsis (LDA). To obtain an accurate model for barley content prediction in coffee, the most sensitive sensor signals were used to apply PLS regression successfully (R2=0.97, RMSEP=3.99% (w/w)).
The aim of this study was to investigate the differences in the proteome patterns of musculus longissimus dorsi between Charolais bulls slaughtered at 500 kg and 700 kg live weight using two-dimensional difference in gel electrophoresis (2D-DIGE) and liquid chromatography-mass spectrometry (LC-MS). Three hundred fifty protein spots were visualised on gels of which 10 showed different expression levels (P<0.05) between groups. After mass spectrometric analysis of spots, beta-enolase (ENO3) in five different spots, alpha-enolase (ENO1), triosephosphate isomerase (TPI1) in two different spots, alpha-actin (ACTA1), and heat shock protein beta-1 (HSPB1) were identified. ENO3, ENO1, TPI1, and ACTA1 had higher expression levels in bulls of 700 kg live weight group. ENO3, ENO1, and TPI1 are involved in energy metabolism, while ACTA1 is a structure protein in skeletal muscle. Up-regulation of heat shock protein beta-1 (HSPB1), which protein is reported to have correlation with tenderness, was observed in 500 kg weight group. Our result demonstrates that proteomic tools are useful in identifying markers associated with muscle development.
The aim of present study was to survey the fatty acid composition and fat content in common carp (Cyprinus carpio L.) fillet captured in five different fish farms located in Hungary. Lipid peroxidation characteristics (conjugated dienes and malondialdehyde levels) were also determined in fish muscle. Data on fatty acid composition of common carp has shown that different methods of rearing and feeding cause significant differences in the proportions of n-6 and n-3 polyunsaturated fatty acids of this fish species. According to present results, it seems that the feeding practice of the last month before capture has determined the fatty acid profile of fillet, therefore the technology of carp nutrition should be divided into two main periods: first a growth and weight gain period; and a second one when the nutritional quality of the fillet composition can be improved.
In the case of a widely used spice — Origanum vulgare subsp. hirtum — the effect of different drying methods (natural, and by using dryers at temperatures of 30°C, 40 °C, 45°C) was investigated referring to the essential oil amount and composition in the final material. The sensory characteristics of olive oils flavoured by the oregano samples were also determined. The essential oil amount and the area percentage of its main component — carvacrol — were significantly influenced by the different drying temperatures. Compared to the natural way of drying in the case of the essential oil content the drying temperature of 40°C and 45°C was preferable for the higher amounts. Referring to the carvacrol area percentage the drying temperature of 30°C resulted in the highest amounts (89.74±0.28%), that was affirmed by the sensory analysis as well; based on the taste descriptions the consumers found it the most pungent one. According to our results sensory analysis data in most of the cases corresponds to the GC-MS measurements and give a much more complex characterisation of a spice.
There are extensive data on effects of antifungal agents on the plant pathogens, especially on Fusariums spp. species. However, investigations on the interaction of chemicals and the treated cultivars are rare. The aim of the study was to test two types of fungicide mixtures, azoxystrobin-propiconazole, and prothioconazole-tebuconazole, which are applied in wheat cultivars intensively, on six fodder maize hybrids that were infected with Fusarium proliferatum in the R1 growth stage in a field trial. The effect of the fungicide treatment was tested on the starch content and antifungal, antioxidant polyphenols of the kernels in the R3–R4 and R6 stage of the cultivars. The level of the fungal presence and the fumonisin concentration of the kernels were increased significantly under the artificial infection. The fumonisin concentration was variable at the R6 stage of the hybrid maize kernels. The treatment with prothioconazole and tebuconazole was found to be suitable when it was done before flowering, while the azoxystrobin-propiconazole treatments were equally successful before and after maize flowering considering the decreasing fumonisin concentration of the kernels. Both fungicide mixtures, when they were applied after maize flowering, affected the starch biosynthesis to the R3–R4 stage significantly. Meanwhile, azoxystrobin-propiconazole also significantly affected the antioxidant flavone/flavanol contents from the R3–R4 stage to the R6 stage.
Peripheral blood stem cells (PBSC) could contribute to tissue regeneration through the ability to form somatic cells. CD34 positivity is regarded as stem cell (SC) or endothelial progenitor cell (EP) marker. According to literature natural substances could increase the release of CD34 positive (CD34+) cells. In this study we investigated the basic rate of CD34+ cells in peripheral blood of CBA/Ca (H-2k haplotype) and BALB/c inbred mice by flow cytometry. Then we treated the mice with a new mixture of medical herbs, and we measured the level of CD34+ cells at 1, 3, 6, 18 and 24 hours after the treatment. A biological rhythm in the untreated blood was detected. Moreover the used herbal compounds increased the number of CD34+ cells.Although SC number is individually and highly variable in peripheral blood, the fluctuation could be used as a biomarker like the other compounds of peripheral blood in different aspects in risk assessment.
Abstract
Quality and storability are crucial factors in production of apple juice. The main goal of this study was investigation of the effects of ascorbic acid and acerola juice on the changes of some sensorial parameters and bioactive compounds of aseptically filled and industrial scale produced apple juice during storage for 12 months. While the viscosity and pH of apple juice did not change significantly, the ΔE* peaked (20–30) at month 6 of the storage period. The colour of apple juice was lighter than at the beginning of storage. Maximum total phenolic contents were 1,100, 1,400, and 1,250 mg L−1 in the control, ascorbic acid supplemented, and acerola added samples, respectively. Other parameters (antioxidant capacity, ascorbic acid, browning index, etc.) peaked in month 4. Acerola was a good alternative anti-browning and antioxidant agent for the treatment of apple juice in the processing. The antioxidant capacity of apple juice treated with acerola was higher than with ascorbic acid. The results were obtained with industrial samples, thus, they can serve as a very good base for the optimisation process and industrial production without the need for scale-up.
Compared to the known method of conjugation the frequency of transposon mutagenesis following conjugation was enhanced 11-fold by two hours of pre-incubation of recipient Pseudomonas viridiflava 1 on conjugation media. The increased frequency was ƒ = 1.3 × 10 −4 . In other species of Pseudomonas, Pectobacteira and Xanthomonas high rates of transposon mutants were similarly obtained; however, in these strains the increased frequency was less than 5-fold.
