Polyphenol components and antioxidant activity of Thymus spp.

  This scientific work was aimed to evaluate the antioxidant potential of aromatic plants of Thymus spp. in the East of Ukraine. These plants are known as medicinal and food around the world. All antioxidant parameters were investigated spectrophotometrically: total content of polyphenols (TPC), the total content of phenolic acids (TPAC), the total content of flavonoids (TFC), molybdenum reducing power of extracts (MRP), and antioxidant activity by DPPH method (DPPH). Investigation of ethanolic extracts demonstrated that TPC varied from 57.89 to 123.67 mg/g gallic acid equivalent (GAE) DW for Th. pulegioides, from 61.43 to 168.18 mg GAE/g for Th. serpyllum, and from 47.36 to 115.67 mg GAE/g for Th. vulgaris. TPAC ranged from 27.36 to 50.22 mg/g caffeic acid equivalent (CAE) DW for Th. pulegioides, from 28.58 to 59.62 mg CAE/g for Th. serpyllum, and from 22.95 to 53.82 mg CAE/g for Th. vulgaris. TFC was determined in a range from 29.88 to 61.23 mg/g quercetin equivalent (QE) DW for Th. pulegioides, from 36.0 to 82.43 mg QE/g for Th. serpyllum, and from 24.59 to 55.41 mg QE/g for Th. vulgaris. MRP was detected in the range of 94.65 – 204.76 mg/g Trolox equivalent (TE) DW for Th. pulegioides, 96.06 – 219.0 mg TE/g for Th. serpyllum, and 87.56 – 215.43 mg TE/g for Th. vulgaris. The antioxidant activity of extracts by the DPPH method was 6.34 – 9.23 mg TE/g for Th. pulegioides, 8.11 – 9.21 mg TE/g for Th. serpyllum, and 4.97 – 9.53 mg TE/g for Th. vulgaris. It was established that polyphenol accumulation depended on the growth stage and species. For all species was found a strong correlation between TPC and TFC (r = 0.938, 0.908, and 0.854). Investigated Thymus spp. are a valuable source of antioxidants that can be used in pharmacological studies and the food industry

The intensification of dehydration process of pectin-containing raw materials

The process of intensifying dehydration of pectin-containing raw materials by using centrifugation with simultaneous application of low-frequency oscillations to the working container creates an electroosmotic effect in unilateral diffusion to improve the filtration process. It is established that to reduce the technological resistance in the presented methods; it is necessary to create a fluidized bed of products due to the oscillating motion of the working capacity. An experimental vibration unit has been developed to determine the rational parameters of the vibrocentric moisture removal process using the electroosmotic effect. It is proved that the complex of the designed equipment provides consecutive carrying out of three-stage vibration filtration-convective drying of high-moisture production by an alternation of action of a stream of the heat carrier, an electromagnetic field, low-frequency fluctuations. According to the research results, the dependences of the kinetics of the moisture diffusion process on the electric field strength are obtained; frequency of electric current and duty cycle of pulses, which allowed to optimize the process parameters according to the criteria of minimizing energy consumption. It was found that the processing time to achieve the desired humidity with the application of vibration, filtration, and electroosmotic effect was twice less than for filtration drying in a fixed bed. In combination with the noted physical and mechanical factors, the proposed technology improves the technical and economic parameters of the studied process

Survey of somatic cell counts and milk composition in bulk milk of ewes in dairy practice

We evaluated milk quality during the sheep dairy period in the year 2018. The study was performed at fifteen dairy farms with differed breeds and crossbreds under Slovakian usual practical conditions (milking and pasture). At the first and seventh farm purebred Tsigai (TS) ewes were kept, at the eight to twelve farm there were purebred Lacaune ewes (LC) and the thirteen farm were kept crossbred Improved Valachian x Lacaune ewes (IV/LC, with a higher proportion of Improved Valachian), the fourteen farm crossbred Lacaune x East Friesian ewes and the last farm were ewes of the synthetic population of Slovak dairy ewe (SD). The milk yield recording and milk sampling were performed once a month during evening milking as a part of milk recording services. The basic milk composition was determined by MilkoScan FT120 (Foss, Hillerød, Denmark) and somatic cell count was determined using a Fossomatic 90 (Foss Electric, Hillerød, Denmark) after heat treatment at 40 °C for 15 min. We found the highest incidence of SCC on farm 14 with crossbred LC/EF 3.940 x 103 cells.mL-1. Followed by farms 12 and 9 with purebred LC (SCC value of 3.318 and 2.489 x 103 cells.mL-1). Farm 7 with purebred TS reached the lowest value (831 x 103 cells.mL-1). The highest fat content was reached by the purebred TS, with gradual growth from March to July. Crossbreds and the synthetic population of Slovak dairy ewe (SD) had the lowest average fat content, which could be affected by feeding. Similar tendencies were found in protein content

The influence of the denitrifying strain of Staphylococcus carnosus No. 5304 on the content of nitrates in the technology of yogurt production

Contamination of food with nitrates is a generally recognized problem. Milk is the basis for the production of many milk mixtures for baby food, and children are considered to be the most vulnerable category to the harmful influence of nitrates. The purpose of the search was to investigate the denitrification of milk with different amounts of nitrates by the denitrifying microorganisms of Staphylococcus carnosus in the technology of production of sour-milk products. The denitrification process of S. carnosus milk in the amount of 103 CFU.cm-3 was found to reduce the nitrate content by an average of 88.0 ±3.9 mg.kg-1 and in the samples of the first group was 10.3 ±2.4 mg.kg-1, the second 110.7 ±4.1 and the third 214.5 ±6.3 mg.kg-1, respectively. In the search of the denitrification process of S. carnosus milk in the amount of 104 CFU.cm-3, was found that in the ready yogurt in the samples of the first group the amount of nitrates was 1.1 ±0.1 mg.kg-1, in the second group 56.4 ±3.5 mg.kg-1, and in the third 159.5 ±4.1 mg.kg-1 respectively. In the search of the denitrification process of S. carnosus milk in the amount of 105 CFU.cm-3, was found that nitrates were practically absent in the samples of the first group, the second group did not exceed 10 mg.kg-1, and the third was 107.4 ±3.9 mg.kg-1. Therefore, received data indicate the possibility of using strain S. carnosus No. 5304 for denitrification of milk with a high content of nitrates in the technology of production of fermented milk products, in particular yogurt

A pilot plant scale of Yellow Konjac (Amorphophallus muelleri Blume) flour production by a centrifugal mill using response surface methodology

This study aimed at investigating the effects of polishing conditions on the physicochemical properties of polished yellow konjac flour (PYKF) with a centrifugal mill using Central Composite Design-Response Surface Methodology (CCD-RSM). Micro-mill milled yellow konjac flour (MMYKF) mass and polishing cycles were the independent variables, with four observed responses (calcium oxalate, viscosity, degree of whiteness (DoW), and glucomannan). The lower limit (-1) and upper limit (+1) for MMYKF mass in this study are 10 and 15 kg, respectively, while the -1 and +1 for the polishing cycle are three times, and seven times, respectively. The optimum prediction occurred at 10 kg of MMYKF mass and six times the polishing cycle with the following characteristics: 0.52 ±0.00% w.b. calcium oxalate, 20362.00 ±16.00 cP viscosity, 62.22 ±0.01 DoW, and 69.43 ±0.02% d.b. glucomannan content, which agreed with the verification data with p-value >0.05 for all observed responses using the paired T-test. Polishing using a centrifugal mill is feasible and promises to be scaled up to industrial scale for yellow konjac flour polishing before the wet extraction process.

Development of the food act of the Slovak Republic from 1995 to 2021

Legislation in food is quite fragmented, it includes several regulations, amendments due to the rapid development both in the studied area and the influence of European law. It is a legal branch of a relatively hybrid nature. It contains agricultural legislation that intersects with environmental law. It also affects administrative, financial, and criminal law as a branch of public law. Nor can commercial and civil law as the basis of private law be circumvented here. The legal norm has undergone a relatively interesting development, which is characterized by several amendments. During the more than 25 years of validity of this legal norm, a total of more than twenty amendments. This certainly does not contribute to the stability of the legislation, the legal certainty of the entities concerned, or its clarity and system. The article provides an overview of the development of the legal regulation of the Food Act in Slovakia from 1995 to 2021

Product line of selected agricultural entity in Slovakia and suggestion for its expansion based on analysis of consumers' interest in dairy and meat products

Studies on primary agricultural production in Slovakia aimed mainly at biological, economic, or market point of view and there is a lack of managerial approach providing a specific recommendation for farmers according to their production lines or planning process. As a reaction, we are providing a practically oriented study based on the selected livestock producer, which is aimed at statistical significances as an establishment for further recommendations for management and marketing of this entity. The paper aims to analyze the views and preferences of customers of the monitored company, which sells its meat and dairy products in its stores and verify the expected success of the planned expansion of the product lines. Regarding this, the online questionnaire study was conducted on a sample of 202 respondents. Realized statistical analysis based on the Kruskal-Wallis nonparametric test and subsequent Bonferroni post hoc correction signify that meat products, fresh meat, and slaughter specialties are the most favorite products among customers of the monitored company. Fresh milk, on the other hand, is not as attractive as a meal for them. However, selling it from vending machines placed out of the store would increase the sales. Dairy products of own production should be even more successful, as we assume they would be as interesting for customers as the currently expanding portfolio of meat products. The benefit of this study lies in the consideration of the practical use of the obtained results in the business practice of the monitored company. Regarding this, we are providing a set of recommendations, according to the planning of their product lines and connected marketing tools for their successful placement on the market

Satureja montana L. essential oil various dosages effect on the main rats’ biological features

An application of natural antioxidants remains the focus of research groups. The effect of Satureja montana L. essential oil in various doses on the main biological characteristics of Wistar rats was the main aim of the study. The intensification of protein metabolism in the blood plasma of rats on the background of the use of Satureja montana L. essential oil was noted. Total protein increases by 17.9 – 19.7%, and albumin by 27.6% in rats of the experimental group received the essential oil at a dose of 0.6 ml per kg of feed. A significant increase in the AST level in control group rats to 207.3 U.L-1 was revealed. Its one to a certain extent indicates the hepatoprotective effect of mountain savory oil and a decrease in inflammatory processes in the organs of the gastrointestinal tract in the conditions of cell maintenance of rats of the experimental groups. Gastric epithelium thickness of rats of both experimental groups was lower than the control animals. But it did not bear any signs of atrophy. The difference of this indicator in comparison with control was 12.75 μm (p ≤0.05) in the second group and it was reliable. The number of chief stomach cells increases in animals of the experimental groups, which may indicate a greater enzymatic activity. An increased dose of mountain savory oil contributes to the formation of more damage to hepatocytes on the periphery of the liver lobule. Thus, the relationship between liver enzymes and the state of peripheral hepatocytes was noted

The comparison of biochemical composition of Actinidia kolomikta and Actinidia polygama fruits

The demand for natural products, which are rich in biologically active compositions, grows constantly. The choice and production of such products can minimize the deficit of importance for human organism components, which are contained only in plant food. The paper contains the laboratory studying results of the chemical composition of the fruits of two Actinidia Lindl. cultivars of Federal State Budgetary Scientific Institution Federal Horticultural Research Center for Breeding, Agrotechnology, and Nursery (FSBSI FSC for Horticulture) genetic collection: Actinidia kolomikta (Rupr. et Maxim.) Maxim. and Actinidia polygama (Siebold et Zucc.) Maxim. All the presented samples are grown in field conditions. The fruits were picked up in the phase of harvest maturity while ripening. The data on antioxidant activity of water and methanol extracts, the content of phenolic compounds sum, soluble solids, and titratable acids in the fruits, and on qualitative composition of secondary metabolites (organic acids, fatty acids, mono-, di- and polysaccharides) are given in the paper. The variation limits of the parameters under study depending on the sample are presented. As a result of the laboratory studies, it was stated that A. kolomikta fruits 10 times exceed A. polygama fruits on all the stated parameters. Only the results on the soluble solids content in the fruits of both cultivars are approximately at the same level (A. kolomikta > A. polygama on 1.16%). The positive correlation between antioxidant activity and the general content of polyphenols is confirmed at both cultivars. Actinidia kolomikta genotypes Chempion and Lakomka and Actinidia polygama ones Tselebnaya and Uzorchataya showed the best results. The correct individual choice of actinidia fruits that are the best ones at the biochemical composition and the content of micronutrients allows supplying the consumers with food products

Ascorbic acid supplementation suppresses cadmium-derived alterations in the fission yeast Schizosaccharomyces pombe

Cadmium (Cd) a highly toxic environmental pollutant, that does not have any physiological function in the organism, represents a great concern for human health as it can be easily transported from its environmental sources to the food chain. Food, water, and air are the major sources of Cd exposure to the population. Cd-mediated impairments of the basic cellular properties largely depend on its ability to enhance the formation of reactive oxygen species (ROS) and thus triggers oxidative stress to the cell. With the use of fission yeast Schizosaccharomyces pombe (S. pombe) as the model organism, we have analyzed the impact of Cd on the cell growth intensity, as it represents the fundamental feature of all living organisms. Cells were incubated with different Cd concentrations for 3, 6, and 9 hours to investigate the effect of Cd on cell growth in a time and dose-dependent manner. Further possible Cd-derived alterations, as the peroxidation of membrane lipids or the functional impairment of the enzymatic antioxidant protection mechanisms, were investigated by determination of the MDA content and via catalase (CAT) activity detection. Moreover, ascorbic acid (AsA) pre-treatment was subjected to investigate the assumed positive effect of AsA against Cd toxicity. We show here on one hand that cells suffer under the influence of Cd, but on the other hand, they substantially profit from AsA supplementation. Because S. pombe is known to shares many molecular, and biochemical similarities with higher organisms, the effect of AsA in cadmium toxicity elimination might be expected to a similar extent also in other cell types