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PL
Celem pracy było określenie wpływu różnego sposobu przemysłowego prażenia ziaren kawy na ogólną zawartość związków fenolowych występujących w jej naparach. W wyniku przeprowadzonych badań wykazano, że proces prażenia powoduje zwiększenie zawartości związków fenolowych ogółem, co jest szczególnie zauważalne w przypadku prowadzenia tego procesu w temperaturze 190°C przez 12 min i15 sek. Dalsze podwyższanie temperatury i czasu obróbki nasion powoduje zmniejszanie się poziomu polifenoli, co związane jest prawdopodobnie z degradacją termiczną wolnej frakcji tych związków, uwolnionej z połączeń glikozydowych i estrowych w czasie ich hydrolizy spowodowanej najniższą temperaturą prażenia. Rodzaj wody użytej do sporządzania naparów miał największy wpływ na ekstrakcję polifenoli występujących w ziarnach kawy najintensywniej prażonych, dla których znacznie korzystniejsze było używanie pozbawionej składników mineralnych wody dejonizowanej.
EN
The aim of the study was to determine the impact of different methods of industrial roasting of coffee beans on the total content of phenolic compounds present in coffee infusions. As a result of the research, it was shown that the roasting process increases the content of total phenolic compounds, which is particularly noticeable when the process is carried out at atemperature of 190°C for 12 min and 15 sec. Further increases in the temperature and time of seed processing resulted in a polyphenols decrease, which is probably related to the thermal degradation of the free fraction of these compounds, released from glycosidic and ester connections during their hydrolysis caused by the lowest roasting temperature. The type of water used to prepare infusions had the greatest impact on the extraction of polyphenols found in the most intensively roasted coffee beans, for which it was much more beneficial to use deionized water without minerals.
PL
Ze względu na panujące trendy związane ze zdrową żywnością burak ćwikłowy (Beta vulgaris L.) jest coraz częściej wybierany przez konsumentów. Możliwość uprawy w szerokiej temperaturze pozwala na występowanie buraka ćwikłowego na całym świecie, a co za tym idzie jest to łatwo dostępny surowiec o każdej porze roku. Burak jest niskokaloryczny i zawiera wiele związków bioaktywnych, takich jak związki fenolowe i betalainy, które pozytywnie wpływają na zdrowie człowieka. Burak ćwikłowy może być spożywany surowy, po obróbce termicznej lub w postaci soku oraz może być składnikiem zup i sałatek, coraz częściej występuje też w przekąskach. Stosowanie buraka w przekąskach pozytywnie wpływa na wartość odżywczą produktu, dzięki czemu ciastka czy lody stają się bardziej wartościowe. Warto zwrócić uwagę na wytłoki, które powstają podczas produkcji soku. Stosowanie wytłoków z buraków w produkcji żywności umożliwi zagospodarowanie odpadu, ale jest to również wartościowy surowiec, bogaty w związki bioaktywne.
EN
Beetroot (Beta vulgaris L.) is becoming increasingly popular among consumers due to healthy food trends. Its ability to grow in a wide range of temperatures allows for global availability, making it an easily accessible raw material year round. Low in calories, beetroot contains bioactive compounds like phenolic compounds and betalains that positively affect human health. It can be consumed raw, cooked, or as juice and is often included in soups or salads, with a growing presence in snacks. The use of beetroot in snacks enhances the nutritional value of products, making items like cakes or ice cream more nutritious. Attention should be paid to the pomace produced during juice production. Utilizing beet pomace in food production not only manages waste but also provides avaluable raw material rich in bioactive compounds.
EN
The purpose of the research was to study the effect of the quercetin-Ferrum complex on the synthesis of plastid pigments and secondary metabolites in berry crops. In the research, biotechnological, physiological, biochemical and statistical methods were used. The ability of quercetin, which is one of the most common flavonol aglycons, to create a chelated complex with Fe2+ and regulate physiological processes associated with oxidation-reduction reactions, synthesis of pigments and metal enzymes when being a supplement of nutrient medium is shown. With the addition of quercetin-Ferrum complex with a fraction of Fe2+ in a concentration equivalent to the base nutrient media composition optimized for the cultivation of berry crops in vitro, regenerated plants showed a sufficiently high regeneration capacity. Based on the indicators of the content of chlorophylls and carotenoids in leaves, the physiological availability of Ferrum in the quercetin-Ferrum complex was established. The concentration of chlorophylls a and b in raspberry and strawberry leaves increased by 20−25%, and the content of carotenoids increased by 30−40%. On the contrary, in black currant, the content of chlorophyll a in leaves decreased by 18−20% and chlorophyll b by almost 75%. It was found that quercetin is a biologically active phenolic chelating agent capable of chemically binding Fe2+ ions and participating in the regulation of growth processes, in particular in the induction of callusogenesis. Metal-flavonol complex is advisable to use in micro clonal reproduction of plants sensitive to oxidative stress in conditions of Fe2+ ions deficiency under the condition of individual selection of the components of the chelate complex and adjusting its concentration in the nutrient medium.
EN
The olive mill waste water (OMWW) are effluents issued from the extraction of olive oil, these effluents are cloudy-looking liquids with a reddish-brown color, their pH varies from 4 to 5. They are very rich in polyphenols, which causes many environmental problems, such as water pollution, Currently, on an industrial scale, there is no reliable, efficient, and less expensive technique for OMWW treatment. OMWW are evaporated in watertight basins or discharged into watercourses. Several techniques have been studied to treat these industrial effluents. The objective of this work was to compare these studies to formulate the recommendations that can be adopted for an effective and cheaper treatment of these effluents which constitute a major environmental problem for water resources. Indeed, it can be concluded that it is very difficult to treat OMWW by conventional methods due to its non-biodegradability and high cost of others methods like distillation and oxidation. In the end, it was concluded that for a better OMWW treatment, it is necessary to start firstly by the adsorption of phenolic compounds which are responsible for the nonbiodegradability of OMWW while using cheaper adsorbents namely clays, bio-adsorbents or apatites, then dilute the OMWW with domestic wastewater. The dilution of OMWW by urban wastewater leads to good mineralization of organic matter by enriching the medium with microorganisms, which facilitates the elimination of the organic load and then we use the usual techniques as a plant filter or active sludge for mixture treatment.
EN
The aim of this study was to determine the effect of the addition of extractive substances on the VOC emission of lacquer products in the liquid state. Three water-soluble acrylic resin products were investigated using the stationary phase microextraction technique in combination with gas chromatography coupled with mass spectrometry (SPME-GC/MS). The extraction of volatile compounds was analysed at three temperatures: 22 ℃, 35 ℃ and 45 ℃. 20 μg of an extract obtained from the leaves, branches and bark of black cherry (Prunus serotina Erhr.) were added to commercial products. Flavonoids accounted for almost 75% of the total phenols in the used extract. The spectrum of volatile compounds emitted by the liquid coating products selected for the studies was examined before and after adding the extract to them. It was found that the addition of black cherry extract caused a significant reduction in the emissions of volatile compounds emitted by the researched products. The compounds, whose amounts did not decrease under the influence of the addition of the extract, were esters of propenoic acid. The applied extract was a source of emissions from an additional compound: benzaldehyde. The total VOC emissions of the investigated liquid coating products was reduced by 8-55% and depended on the extraction temperature. The paper also proposes the mechanism of chemical reactions between phenolics and VOC, which may cause the reduction in VOC emissions from lacquer products. The IBM RXN tool was utilised to find possible reactions.
EN
Liquid chromatography-mass spectrometry was used to detect and analyze phenolic compounds in the surface waters of four urban lakes in Xi’an – Hancheng Lake, Xingqing Lake, Nanhu Lake, and Taohuatan Lake. A total of 5 phenolic compounds were detected from the water samples, with a concentration range of ND-100.32 ng/L, of which bisphenol A (BPA) and nonyl phenol (NP) were the main types of phenolic compounds pollution in the four lakes. Pearson correlation analysis was used to analyze the concentration of phenolic compounds in the lake waters of Xi’an City and the water quality indicators COD, TP, NH3 -N, DO, and pH during the same period. It was found that there was a significant positive relationship between the concentration of BPA and COD, the concentration of estradiol (17-beta-E2), estrone (E1) and TP and TN, the concentration of octylphenol (4-t-OP) and pH. The ecological risk assessment (ERA) shows that the concentration of BPA, 4-t-OP and NP in the lakes is at a medium risk level( is between 0.1–1), and that of E1 is at a high risk level (is greater than 1). Female cells (breast cancer cells) and male germ cells (testis cells) of mice were used as research objects to explore BPA and NP Toxic effect on mouse germ cells. BPA and NP at a concentration of 10-8 mol/L were found to have the most value-inducing effect on MCF-7 breast cancer cells positive for estrogen receptor. Obviously, both BPA and NP can induce the proliferation of testicular Sertoli cells.
EN
Fruits, vegetables and yeast contain numerous biologically active compounds called "phytonutrients". The phytonutrients can include phenolic compounds, minerals and vitamins. Conventional techniques used to extract these nutrients suffer from several disadvantages. These methods are characterized by poor efficiency of the extraction process, high energy and solvent consumption, long processing times and the formation of thermal decomposition by products. For this reason, scientists together with food engineers are looking for a safe and efficient extraction of bioactive compounds. In recent years, several modern techniques to support the extraction process have been proposed. One of them is the pulsed electric field (PEF). Pulsed electric field is one of the non-thermal methods used to control microbiological safety and change the properties (nutritional, sensory and physicochemical) of food products. The principle of operation of PEF is based on the formation of pores in the cell membrane under the influence of short bursts of electricity, which increases its permeability. Due to the formation of pores, various components, such as ions, molecules and other more complex compounds, such as vitamins or lipids, can flow freely through the cell membrane. The use of PEF for extraction reduces the process time, increases the efficiency of the process and is characterized by a low processing temperature. This review shows the use of a pulsed electric field as a process supporting the extraction of biological compounds from algae, vegetables, fruits and in the brewing industry. The optimal conditions of the pulsed electric field, which may affect the extraction efficiency, e.g. electric field strength, number of pulses and pulse width, are also discussed. Based on the collected literature data, it was found that the pulsed electric field contributes to the increase of the extraction efficiency.
EN
This study is the evaluation of the coagulation efficiency of the aluminum sulfate on the removal of catechol and pyrogallol. The study has focused on the impact of inorganic components of hardness Algerian waters. Jar-test trials were conducted on the two phenolic compounds dissolved in distilled water only, which was later enriched with minerals. Several reaction parameters varied, including the effect of pH and the influence of the salt content, and this approach yielded a better understanding of interaction between phenolic compounds and calcium/magnesium salts. The results indicate that the process efficiency depends on the number and position of OH in molecules. The main mechanisms would be either a physical adsorption, an exchange of ligand, or complexation on the floc surface of aluminum hydroxide. Moreover, the addition of inorganic salts appears to improve removal efficiency of tested phenolic compounds and have an effect on the optimal pH range for coagulation.
PL
Przeanalizowano wpływ sposobu produkcji kaszy gryczanej i czasu jej przechowywania na zawartość występujących w niej związków fenolowych. Wykazano, że kasze produkowane w różnych zakładach zawierają inny poziom tych składników, a różnice w przypadku niektórych z nich są nawet dziesięciokrotne. Podczas przechowywania kasz gryczanych zawartość fenolowych związków w większości przypadków obniżała się, a na tempo i kierunek obserwowanych zmian miały wpływ warunki ich produkcji. Wszystkie kasze gryczane są dobrym źródłem związków fenolowych w diecie człowieka, ale największą wartość ma kasza nieprażona.
EN
Buckwheat groats roasted in 3 Polish grain mills were studied for changes in the content of phenolic compds. (rutin as well as coumaric, ferulic, syringic and vanillic acids) during 4-12 months long storage at below 20°C and humidity below 75%. During the storage, the content of phenolic compds. in most cases decreased, and the rate and direction of the observed changes depended on the prodn. conditions. In general, contents of the phenolic compds. in roasted groats decreased during the storage except for syringic acid.
10
PL
Analizowano wpływ sposobu ekstrakcji wodą liści herbaty zielonej na zawartość w naparze działających prozdrowotnie związków fenolowych. Wykazano, że na efektywność ekstrakcji wpływa nie tylko jej czas i krotność, ale również stopień rozdrobnienia liści herbaty. Przy pierwszym kontakcie z gorącą wodą herbata liściasta uwalnia większą niż herbata ekspresowa ilość związków fenolowych w naparach sporządzanych do 3 min. Po tym czasie korzystniejszym źródłem tych związków stają się napary herbaty ekspresowej. Herbatę o dużych liściach warto ekstrahować przynajmniej dwukrotnie, a w przypadku liści rozdrobnionych efektywna jest jedynie pierwsza ekstrakcja. Ponowne wykorzystanie liści herbaty już ekstrahowanych powoduje przejście do naparów mniejszej ilości związków fenolowych, co jest wyraźnie zauważalne we wszystkich naparach herbaty liściastej i sporządzanych dłużej niż 5 min naparach herbaty ekspresowej.
EN
Aq. infusions of com. green tea with varying degrees of leaf refinement (whole and finely cut) were prepd. by flooding with boiling water for 1-15 min without mixing. Total polyphenolic content in the infusions was detd. by using the Folin-Ciocalteu assay. In order to obtain infusions with the highest polyphenolic content, the tea was extd. longer than 3-5 min. The tea with whole leaves was extd. at least twice, while in the case of finely cut leaves only the first extn. was effective.
PL
Badano podatność na rozkład związków organicznych (w tym związków fenolowych) obecnych w retentatach uzyskanych po ultrafiltracji i odwróconej osmozie oczyszczonych ścieków miejskich, stosując dwustopniowy proces ozonolizy i fotolitycznego utleniania. Wykazano, że podczas ozonolizy i fotolizy związki te zostają usunięte, przy czym stopień usunięcia zależał od czasu ekspozycji matrycy na czynnik utleniający. Skojarzenie ozonolizy i fotolizy umożliwiło zwiększenie efektywności usuwania badanych zanieczyszczeń, przy czym niektóre z nich (np. związki fenolowe) były usuwane w zadowalającym stopniu już w procesie jednostopniowym, po ozonolizie.
EN
Real retentates from the treated wastewater were studied for content of total, org. and inorg. C, total N, PhOH index and absorbance at 254 nm. Samples were taken after 30 min exposure to O₃ and after 15, 30, 60, and 120 min long irrdn. with UV. A decrease in total C content, PhOH index and absorbance was obsd. The combination of ozonolysis and photolysis resulted in increasing the effectiveness of wastewater treatment.
EN
The tradition of wine production and consumption has been known since ancient times. Consumption of wine is particularly widespread in the Mediterranean countries. Wine is composed mainly of water, ethanol, carbohydrates, organic acids, minerals and phenols that shape the taste, aroma and colour of the final product. Phenolic compounds contained in wine also determine its beneficial effect on health. The aim of this article is to characterize the phenolic compounds of wine, as well as presenting the impact of the raw material and wine production process on phenolic content, as well as its healthy properties.
PL
Tradycja produkcji i konsumpcji wina sięga czasów starożytnych. Spożycie wina jest szczególnie rozpowszechnione w krajach basenu Morza Śródziemnego. Wino składa się głównie z wody, etanolu, węglowodanów, kwasów organicznych, składników mineralnych oraz związków fenolowych, które kształtują smak, aromat i barwę produktu finalnego. Obecność związków fenolowych w winie decyduje także o jego korzystnym wpływie na zdrowie. Celem artykułu jest charakterystyka zawartych w winie związków fenolowych, a także przedstawienie wpływu zastosowanego do produkcji wina surowca oraz procesów produkcji wina na zawartość fenoli, jak również ich prozdrowotne właściwości.
EN
Beer is one of the most consumed types of alcoholic beverage in the world.Beer is brewed using the following ingredients: water, barley, hops and yeast, but the selection of the raw materials and brewing processes determines the nutritional value and content of phenolic compounds in the final product. The aim of this article is to characterize the phenolic compounds of beer, as well as presenting the impact of the beer production process on its antioxidant properties.
PL
Piwo jest jednym z najpowszechniej spożywanych napojów alkoholowych na świecie. Podstawowymi składnikami wyko-rzystywanymi do produkcji piwa jest woda, jęczmień, chmiel i drożdże, a dobór surowców i procesów warzenia determinuje wartość odżywczą i zawartość związków fenolowych w final-nym produkcie. Celem artykułu jest charakterystyka obecnych w piwie związków fenolowych, a także przedstawienie wpływu poszczególnych procesów produkcji piwa na zawartość fenoli, jak również na jego właściwości antyoksydacyjne.
EN
The study of the kinetics of extraction of phenolic compounds and flavonoids from crushed roots of Carlina acaulis using 40% and 70% of water-ethanol mixture by infusion method is described in the article. The total value of the mass transfer coefficient and the value of the transfer coefficient through the cell wall, in the intercellular space and the volume of the extractant were determined. Particles of Carlina acaulis roots of different sizes (0.2, 0.3, 0.5 mm) were studied; different concentrations of ethyl alcohol were used - 40% and 70%; the ratio of raw materials: extractant was 1:10. The analytical dependence of the mass transfer coefficient k and the leaching coefficient A on the solid particle size d and the concentration of the extractant was obtained, which allows to predict the extraction process and to design equipment for the technological process in production. Kinetic equations of the process of extraction of phenolic compounds and flavonoids from Carlina acaulis roots by infusion method are derived. The obtained equations allow to determine the concentrations of phenolic compounds and flavonoids in the extracts at a given point in time with a particle size of the solid phase from 1 to 10 mm, as well as to determine the optimal diameter of the solid phase particles for maximum extraction of the target substance.
EN
The paper examines single- and multicomponent adsorption onto granular activated carbon. The quantities adsorbed in the study were determined using HPLC with UV detection. The experimental data were analysed using the Langmuir, the Freundlich and the Sips adsorption isotherms. With a single component being adsorbed, high coefficients of determination and low mean square errors indicated that the Sips isotherm fitted the adsorption equilibrium well. Further experiments were carried out using aqueous solutions containing two or three adsorbed components in different proportions. For these solutions, the literature methods of predicting multicomponent equilibrium using single-component data did not yield positive results. Assuming that in the investigated range of concentrations no competitive adsorption occurred, the authors propose a method for calculating the equilibrium concentrations in the liquid phase using the equations obtained for individual components. The results achieved correspond very well to the experimental data.
PL
Określono wpływ rodzaju ekstrahenta oraz sposobu przygotowania owoców rokitnika na wydajność ekstrakcji, właściwości przeciwutleniające i całkowitą zawartość związków fenolowych w ekstraktach oraz zmianę chromatycznych współrzędnych barwy uzyskanych ekstraktów. Przeprowadzono ekstrakcję świeżych oraz suszonych metodą konwekcyjno- mikrofalową owoców rokitnika zwyczajnego, stosując jako ekstrahenty etanol, aceton i mieszaninę etanolu z acetonem. Uzyskane ekstrakty następnie suszono sublimacyjnie do uzyskania końcowej wilgotności 3%. Wykorzystanie świeżych owoców z rokitnika pozwalało na uzyskanie ekstraktów o większej całkowitej zawartości związków fenolowych i wyższej aktywności przeciwutleniającej. Z kolei zastosowanie suszu umożliwiło uzyskanie zdecydowanie większej ilości ekstraktów o lepszym odwzorowaniu barwy w porównaniu z surowcem.
EN
EtOH, Me2CO and their mix. (50:50 by vol.) were used for extn. of fresh and dried sea buckthorn fruits. The exts. from dried fruits were freeze-dried at 40°C under pressure of 63 Pa. The exts. from dried fruits showed a lower total content of phenolic compds. and lower antioxidant activity than those obtained from fresh fruits. EtOH was the best extractant.
EN
During our studies concerning the isolation of sulfated polysaccharides (SPs) from freshwater algae species widespread in Poland, an improved overall extraction methodology has been developed. This new, multi-step procedure allows for obtainment of several fractions that could find use in cosmetic and food industries, with the final one containing the valuable SPs, important both from economic and scientific perspective. Moreover, the process allows for easy use of typical chelating agents to remove harmful heavy metal ions without important losses in natural compounds of interest. Furthermore, a material balance has been established for said process, allowing for its easier implementation on bigger scales, and highlighting the areas which could still be improved to positively affect the final time-cost ratio of the methodology. Combined with previously published information concerning the detailed composition of obtained fractions, we aim to provide a robust and informative outlook on the potential of native freshwater algae species as cheap, raw and easily purifiable resource, usable in a number of important industries. According to the mass balance, nearly 5 % of dry mass of Cladophora glomerata is extractable with ethanol and this fraction consists mostly of fatty acids, phenolics and pigments. Another 5 % of mass can be isolated as pure SPs from aqueous fraction. Additionally, calcium from natural incrustations on the surface of C. glomerata amounts to 17 % of dry material weight and can be reclaimed from acidic wash by simple precipitation; such calcium salts have garnered significant interest as nutritional supplements.
EN
Different parts of plants, including fruits, leaves, roots, bark, stem and flower, are a promising source of bioactive compounds, therefore they are intensively studied for biological activity and the possibility of use in functional foods and dietary supplements. The present research compares the phenolic profile and antioxidant capacity of aqueous extracts obtained from bark, flowers and fruits of guelder rose. Antioxidant activity was evaluated against ABTS, hydroxyl and peroxyl free radicals, and as a reducing power by using in vitro test. The total phenolics, flavanols and proanthocyanidins were assessed by spectrophotometric methods, and individual phenolic compounds were also determined using UPLC analysis. Bark water extract proved to be richest in natural antioxidants because it showed the highest antioxidant potential, regardless of the method used. Its very high antioxidant capacity was connected with high phenolic compounds content, especially flavanols and proanthocyanidins. Water extracts of guelder rose fruits and flowers were characterized by the high level of hydroxycinnamic acids, especially chlorogenic acid. It seems that guelder rose bark may be selected as potential source of phytochemicals with high antioxidant potential.
EN
The aim of the study was to evaluate the influence of type of the solvent (water, aqueous ethanol and ethanol) on the antioxidant properties of four various herbs: couch grass (A. repens), milk thistle (S. marianum), dandelion (T. officinale) and fireweed (E. angustifolium) measurement by three common UV-VIS methods (TPC, ABTS+, DPPH). The results were collected through the Vision-Pro™ UV-VIS spectrophotometer software. Aqueous ethanol was the most effective solvent for extraction for all type of herbs. Fireweed contains the highest amount of polyphenol compounds (0.625 μg GA/ml). The lowest antioxidant capacity was presented by extracts from couch grass (0.019 μg GA/ml).
20
Content available remote Wpływ procesu granulowania na właściwości chemiczne wytworzonego granulatu
PL
Określono wpływ procesu granulowania na właściwości chemiczne granulatu wytworzonego z mieszaniny otrębów i wytłoków jabłkowych. Sporządzono mieszanki otrąb z dodatkiem 10, 15 i 20% wytłoków jabłkowych i pozostawiono je na 24 h w celu wyrównania wilgotności. Proces granulowania przeprowadzono przy prędkości obrotowej układu rolek zagęszczających nr = 170 rpm, przy masowym natężeniu przepływu surowca przez układ roboczy Q = 150 kg/h oraz przy szczelinie między rolkami a matrycą hr = 0,4 mm. Na podstawie przeprowadzonych badań stwierdzono wzrost zawartości związków fenolowych w badanym materiale roślinnym po procesie granulacji. Największą ilość związków fenolowych uzyskano w mieszance otrąb z 20-proc. dodatkiem wytłoków jabłkowych (3,913 mg/gproduktu), a najmniejszą z 10-proc. dodatkiem wytłoków jabłkowych (2,451 mg/g produktu).
EN
An apple pomace was mixed with wheat bran (10-20% by mass) and granulated (rotational speed of rollers 170 rpm, 8 mm gap between rolls and matrix). The raw materials and granulates were studies for content of phenolic compds. The granulate with 20% addn. of pomace showed the highest content of phenolic compds.
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