Antioxidant capacity, total phenolic compounds and fatty acids composition in walnut oil and bagasse pellets produced at different parameters of the screw press

Different rotational speeds and nozzle diameters of screw press were used to process walnut kernels. To evaluate the influence of pressing conditions on the quality of walnut oil and bagasse pellets the oil pressing temperature, yield of oil, total phenolic compounds, antioxidant capacity and fatty acid composition were measured. The results show that the pressing at different conditions affected the antioxidant capacity and TPC of either bagasse pellets and pressed oil. Higher values of antioxidant capacity and TPC were measured in bagasse pellets than in pressed oils. Higher amount of pressed oil was yielded by using lower nozzle diameter, however, by lowering the nozzle diameter the oil pressing temperature was rising, which affected the fatty acids. Positive correlations with oil pressing temperatures were calculated at saturated fatty acids, while the correlation coefficients of polyunsaturated fatty acids were positive, but not significant. Monounsaturated fatty acids were negatively affected by higher oil pressing temperatures showing, that monounsaturated fatty acids were more susceptible to higher temperatures than polyunasturated and saturated fatty acids.O

Studium antioxidačnej kapacity

This thesis dealing with the study of antioxidant capacity was developed between 2006-2011 at the Department of Post-Harvest Technology of Horticultural Products, Faculty of Horticulture, Mendel University in Brno. The aim of this thesis was the evaluation of photo-chemiluminescence method and its optimization for determining the antioxidant capacity by the Bux Photochem device. The assessment of impact of selected substances and treatment of experimental material on measured values of antioxidant capacity. The other aim of this thesis was the monitoring of development of antioxidant capacity of the grapes during ripening period and during the process of alcoholic fermentation. The basic principles of measuring the antioxidant capacity by photo-chemiluminescence method are provided by compliance of the methodology with an emphasis on the same treatment of the device. The work showed that the dilution of the observed samples affects the antioxidant capacity measured by Photochem Bux PCL. The solutions of the reference wine and the antioxidant rutin showed higher antioxidant capacity at the samples with higher dilution level. At the parallel extraction by non-polar and polar extractants and the subsequent summation of the measured values of TAC was shown that the resulting value was higher than at the consecutive extractions. Therefore the summation of the values is not appropriate for parallel extractions of antioxidants obtained from the extractants with various polarities. During the extractions 75% methanol was evaluated as the best extractant of antioxidants present in grapes. It is necessary to homogenize the sample before extraction. All the extraction operations must be finished in the shortest time possible. It was shown that all the extraction operations apart from used extractant and re-extraction have demonstrable effects on degradation of antioxidants extracted from the samples. Therefore it is necessary to describe all the extraction procedures perfectly. Very suitable extraction procedure is a re-extraction. There is a big difference in concentrations of extracted substances and extractant occurring during re-extraction, so the extraction is very effective. It was observed that one of the factors causing the degradation of antioxidant compounds during the extraction procedures is the presence of atmospheric oxygen. Sulphites present in wine do not affect the value of antioxidant capacity measured by photo-chemiluminescence method. Conversely, FRAP method has a positive response to the presence of sulphites in wine, so the values measured by this method are affected by the sulphites content. The impact of alcohol content on antioxidant capacity measured by photo-chemiluminescence method was not demonstrated. The monitoring of the antioxidant capacity development in grapes during the ripening period showed that the white varieties have no characteristic development. The blue varieties showed that during the ripening period the values of antioxidant capacity were gradually increasing up to three times the first measurement (46 days before the harvest). The antioxidant capacity of grape juice was increasing during the alcoholic fermentation only if the juice was left in the contact with skins. There was no increase of antioxidant capacity observed after the pressing, although the fermentation process was highly reductive and took place in closed containers

Randomly CncupCmC_{n} cup C_{m} graphs

A graph $G$ is said to be a randomly $H$ graph if and only if any subgraph of $G$ without isolated vertices, which is isomorphic to a subgraph of $H$, can be extended to a subgraph $F$ of $G$ such that $F$ is isomorphic to $H$. In this paper the problem of randomly $H$ graphs, where $H = C_{n} cup C_{m}$, $m eq n$, is discussed

Effect of sample dilution on estimated values of antioxidant capacity by photochemiluminiscence method

This paper describes principles of a proper dilution of samples used for the determination of antioxidant capacity by means of a photochemiluminiscence method using the instrument Photochem (Analytik Jena AG). The authors used the method ACL (Lipid-soluble Antioxidant Capacity), which is one of two methods enabling to measure in this instrument. It was demonstrated that values measured by the photochemiluminiscence method ACL were influenced by the degree of sample dilution. When studying effects of dilution of samples of wine and rutin, it was demonstrated that there is a non-linear correlation between the degree of dilution and measured values of antioxidant capacity. At low molar amount of substance (i.e. at 0.5 and 1.0 nmol), the measured value of rutin inhibition was higher than the same that molar amount of trolox. At higher molar amounts (i.e. 3; 4 and 5 nmol), the inhibition value of trolox was higher. This dependent change can be explained by means of a different effectiveness of antioxidants and a different stability of their products with radicals

Effects of Blended Learning in Teaching Mathematics in Higher Education

Blended learning represents a combination of online learning and face-toface instruction. While one group of researchers advocates the use of blended learning in teaching, others are more critical to the use of ICT in education. The paper deals with utilization of blended learning in teaching mathematics at Faculty of Education, Trnava University. From the results it follows that proper integration of ICT into teaching can make the teaching process more efficient

Študija izvedljivosti - ekonomska upravičenost postavitve sončne elektrarne

summary:A graph is called distance integral (or $D$-integral) if all eigenvalues of its distance matrix are integers. In their study of $D$-integral complete multipartite graphs, Yang and Wang (2015) posed two questions on the existence of such graphs. We resolve these questions and present some further results on $D$-integral complete multipartite graphs. We give the first known distance integral complete multipartite graphs $K_{p_{1},p_{2},p_{3}}$ with $p_{1}<p_{2}<p_{3}$, and $K_{p_{1},p_{2},p_{3},p_{4}}$ with $p_{1}<p_{2}<p_{3}<p_{4}$, as well as the infinite classes of distance integral complete multipartite graphs $K_{a_{1} p_{1},a_{2} p_{2},\ldots ,a_{s} p_{s}}$ with $s=5,6$

Procedure to reduce sulphite in wine with anion-exchange resin

The aim of this experiment was to eliminate SO2 ions present in wine using the anion-exchanger resins. To compare the effectiveness, 2 following strongly basic anion-exchange resin were used. When activated, the sodium bicarbonate solution (activation solution I) is used to prevent parallel reduction of sulphites, tartates and malates, so the anion-exchange resins were activated in two-step activation. In the second step, it was immersed into a mixture of malic acid and tartaric acid (1:1). After the application of anex into wine, the content of total SO2 was reduced to 97–201 mg.L−1 (depending on the amount of anex added into the wine sample). According to our expectations, the variants with anion-exchange resin activated only with bicarbonate solution, the tartrates and malates were significantly reduced. If the anion-exchange resin was activated with a two-steps activation, the tartaric acid and malic acid were reduced in the range of ± 0.13 g.L−1. This phenomenon was strongly reflected at the anion-exchanger Aqua Osmotic 02. The changes in antioxidant content were not affected by the type of anion-exchange resin, the method of activation, or an amount of used anion-exchanger. The color parameters of wine, expressed by the L * a * b *, were not significantly affected by the effects of anion-exchange resin use

Lignans Extract from Knotwood of Norway Spruce—A Possible New Weapon against GTDs

Grapevine trunk diseases (GTDs) pose a major threat to the wine industry worldwide. Currently, efficient biological methods or chemical compounds are not available for the treatment of infected grapevines. In the present study, we used an extract from the knotwood of spruce trees as a biological control against GTDs. Our in vitro trial was focused on the antifungal effects of the extract against the most common GTD pathogens—Cadophora luteo-olivacea, Dactylonectria torresensis, Diaporthe ampelina, Diaporthe bohemiae, Diplodia seriata, Eutypa lata, and Phaeoacremonium minimum. Our in vitro trial revealed a high antifungal effect of the extract against all tested fungi. The inhibition rates varied among the different species from 30% to 100% using 1 mg·mL−1 extract. Subsequently, the efficiency of the extract was supported by an in planta experiment. Commercial grafts of Vitis vinifera were treated with the extract and planted. The total genomic DNA of grapevines was extracted 10 days and 180 days after the treatment. The fungal microbial diversities of the treated/untreated plants were compared using high-throughput amplicon sequencing (HTAS). Treated plants showed 76.9% lower relative abundance of the genus Diaporthe and 70% lower relative abundance of the genus Phaeoacremonium 10 days after treatment. A similar scenario was observed for the genus Cadophora 180 days after treatment, where treated plants showed 76% lower relative abundance of this genus compared with untreated grapevines