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Wyświetlanie 1-15 z 145
Tytuł:
Content of carotenoids in roots of seventeen cultivars of Daucus carota L.
Autorzy:
Mech-Nowak, Aleksandra
Świderski, Adam
Kruczek, Michał
Łuczak, Irena
Kostecka-Gugała, Anna
Powiązania:
https://bibliotekanauki.pl/articles/1039802.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
carotenoid
carrot
antioxidant activity
Opis:
The aim of this study was to compare the content of carotenoids in seventeen cultivars of carrots grown in Poland. Conventional orange cultivars with rarely grown were compared: white, yellow and purple with yellow core cultivars. To determine the content of carotenoids, extracts from lyophilized carrot roots were prepared and analyzed by spectrophotometric as well as HPLC methods with DAD detector. The highest content of carotenoids was found in cultivars: 'Korund F1' (48 mg/100g of fresh weight) and 'Salsa F1' (36 mg/100g of fresh weight). The antioxidant properties of selected cultivars were compared using the DPPH method.
Źródło:
Acta Biochimica Polonica; 2012, 59, 1; 139-141
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The application of modified layered double hydroxides in selective catalytic reduction of nitrogen oxides by ammonia (NH3-SCR)
Autorzy:
Szymaszek, Agnieszka
Motak, Monika
Samojeden, Bogdan
Powiązania:
https://bibliotekanauki.pl/articles/778916.pdf
Data publikacji:
2020
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
Yerba
antioxidant activity
infusions
minerals
Opis:
Selective catalytic reduction with ammonia (NH3-SCR) is very efficient DeNOx technique. According to some problems with the commercial catalyst, novel one should be prepared. Hydrotalcites are potential precursors of the new catalysts of NH3-SCR. In this paper, several attempts to apply these materials in NH3-SCR are presented.
Źródło:
Polish Journal of Chemical Technology; 2020, 22, 1; 61-67
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of the Yerba mate (Ilex paraguariensis) brewing method on the content of selected elements and antioxidant potential of infusions
Autorzy:
Janda, Katarzyna
Jakubczyk, Karolina
Łukomska, Agnieszka
Baranowska-Bosiacka, Irena
Rębacz-Maron, Ewa
Dec, Karolina
Kochman, Joanna
Gutowska, Izabela
Powiązania:
https://bibliotekanauki.pl/articles/779918.pdf
Data publikacji:
2020
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
Yerba
antioxidant activity
infusions
minerals
Opis:
Yerba mate is a source of biologically active substances. The aim was to determine whether the place of origin of Yerba and the brewing method have any influence on the levels of Ca, Mg and Fe and antioxidant activity of infusions. Samples were steeped in cold water (25o C) and hot water (three consecutive infusions with 85o C water). Infusions had a high antioxidant activity and high Mg level. The levels of elements and the antioxidant activity were influenced by the brewing method. There were no significant differences in the examined parameters depending on the country of origin. The results on the levels of elements and the antioxidant activity indicate that the most efficient brewing method was infusion in hot water. The highest levels of elements were found in first infusions, with the highest antioxidant activity in the third infusions.
Źródło:
Polish Journal of Chemical Technology; 2020, 22, 1; 54-60
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
BIOLOGICAL ACTIVITIES OF DIFFERENT EXTRACTS FROM ALLIUM URSINUM LEAVES
Autorzy:
Tomovic, Marina T.
Krivokapic, Milos Z.
Jakovljevic, Vladimir L.
Sovrlic, Miroslav M.
Bradic, Jovana V.
Petkovic, Anica M.
Radojevic, Ivana D.
Brankovic, Snezana R.
Comic, Ljiljana R.
Andjic, Marijana M.
Kocovic, Aleksandar G.
Powiązania:
https://bibliotekanauki.pl/articles/895571.pdf
Data publikacji:
2020-02-29
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
antioxidant activity
antimicrobial activity
Allium ursinum
Opis:
The aim of our study was to evaluate and compare antioxidant and antimicrobial activity of aqueous, methanol and chloroform extracts of leaves of Allium ursinum (A. ursinum). Total phenol (TPC) and flavonoid (TFC) content in extracts and antioxidant activity using DPPH (1,1- diphenyl-2-picrylhydrazyl) assay were determined spectrophotometrically. In vitro antimicrobial activity was tested by microdilution method. The highest TPC and TFC were observed for chloroform extract. The extracts showed different degrees of antimicrobial activity. The intensity of antimicrobial action varied depending on the group of microorganism and the type of extracts. Our results demonstrated rational basis for the traditional uses of A. ursinum in alleviation of oxidative stress and against various pathogenic microorganisms.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2020, 77, 1; 121-129
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of water on the estimation of antioxidant properties of essential oils
Autorzy:
Olszowy, Małgorzata
Powiązania:
https://bibliotekanauki.pl/articles/764073.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
antioxidant activity
essential oils
water impact
Opis:
This study discusses the influence of water content in measuring system on the estimation of antioxidant activity of essential oils. The presented data show that the antioxidant activity of thyme, clove, summer savory and basil essential oils strongly depends on water concentration what has important impact on the estimation of correct and reliable antioxidant activity of examined essential oils.
Źródło:
Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia; 2015, 70, 2
2083-358X
Pojawia się w:
Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of an electrochemical method for the measurement of antioxidant capacity of pure compounds and natural substances extracts
Autorzy:
Lanez, T.
Rebiai, A.
Powiązania:
https://bibliotekanauki.pl/articles/411914.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
antioxidant activity
superoxide anion radical
electrochemistry
DDPH
Opis:
A new method has been developed to measure total antioxidant activity of antioxidants in foods and natural substances without use of standard antioxidants and without use of calibration curves plotting. It is based on measuring the oxidation peak current of superoxide anion radical electrochemically generated by reduction of commercial molecular oxygen in dimethylformamide. The method has been validated using 7 known standard antioxidants and the results have been compared with those obtained by the DPPH and molybdate ion reduction assays. Measured antioxidant capacities were highly correlated with those obtained using DPPH (r2 = 0.549) and molybdate ion reduction assay (r2 = 0.434).
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 1; 46-54
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antioxidant activity of extract of pea and its fractions of low molecular phenolics and tannins
Autorzy:
Amarowicz, Ryszard
Troszyńska, Agnieszka
Powiązania:
https://bibliotekanauki.pl/articles/2051047.pdf
Data publikacji:
2003
Wydawca:
Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
Tematy:
pea
antioxidant activity
antiradical properties
phenolics
tannins
Opis:
Phenolic compounds were extracted from pea (Pisum sativum) seeds using 80% aqueous acetone. Crude extract was applied onto a Sephadex LH-20 column. Fraction I of low molecular phenolic compounds was eluted from the column by ethanol. Fraction II of tannins was obtained using water-acetone (1:1; v/v) as mobile phases. Phenolic compounds present in extract and its fractions showed antioxidant and antiradical properties investigated using a β-carotene-linoleate model system, Total Antioxidant Activity (TAA) method, DPPH radical scavenging activity and reducing power. The results of assays performed were the highest when tannins (fraction II) were tested. For example, TAA of tannin fraction was 2.48 µmol Trolox/mg, whereas the extract and fraction I showed only 0.30 and 0.22 µmol Trolox/mg, respectively. The content of total phenolics in fraction II was found the highest (113 mg/g). The content of tannins in this fraction determined using the vanillin method and expressed as absorbance units at 500 nm per 1 g was 368. The HPLC analysis of pea crude extract showed the presence of such phenolic compounds as vanillic, caffeic, p-coumaric, ferulic and sinapic acids (after basic hydrolysis), quercetin and kaempherol, procyanidin B2 and B3.
Źródło:
Polish Journal of Food and Nutrition Sciences; 2003, 53, 1s; 10-15
1230-0322
2083-6007
Pojawia się w:
Polish Journal of Food and Nutrition Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis, Characterization, In-Vitro Antimicrobial Evaluation and Antioxidant Studies of Some Isoxazoline Derivatives
Autorzy:
Vishnupriya, P.
Rubala mary, M.
Powiązania:
https://bibliotekanauki.pl/articles/1112444.pdf
Data publikacji:
2018
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Chalcone
antibacterial
antifungal
antioxidant activity
isoxazole
synthesis
Opis:
The tremendous rise in development of resistance to antimicrobials has created an alarming situation for researchers and clinicians. In this regard, an attempt has been made to develop a series of azole-based derivatives. The presented study consists of the design and synthesis of some newer derivatives by incorporating the isoxazole nucleus in the pharmacophore. These are also characterized physicochemically and by spectral means (IR and microanalysis). Moreover, the antioxidant activity of these derivatives was assessed using DPPH radical scavenging methods Finally, all of the newly isolated compounds were tested for their antimicrobial activities. Herein, antimicrobial screening using the agar disc diffusion method revealed that the majority of the derivatives are most active.
Źródło:
World News of Natural Sciences; 2018, 18, 2; 72-78
2543-5426
Pojawia się w:
World News of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of antioxidactivity of green and black tea (Camellia sinensis) and rooibos (Aspalathus linearis) tea extracts by means of hplc with reaction detector
Autorzy:
Milašiene, R.
Rawicka, K.
Kornyšova, O.
Ligor, M.
Maruška, A.
Buszewska, B.
Powiązania:
https://bibliotekanauki.pl/articles/346957.pdf
Data publikacji:
2007
Wydawca:
Politechnika Bydgoska im. Jana i Jędrzeja Śniadeckich. Wydział Technologii i Inżynierii Chemicznej
Tematy:
antioxidant activity
HPLC
reaction detector
DPPH
tea
Opis:
Antioxidants are chemical compounds that scavenge free radicals in organisms and protect most important biomolecules such as DNA, proteins, lipids from their damaging activity. Antioxidants reduce a risk of cancer, inflammations, arthritis, cardiovascular diseases and others. The objective of this study was to prepare extracts of different tea species (Camellia sinensis, Aspalathus linearis) in order to compare their antioxidant and radical scavenging activities using reaction detection. Methanolic black, green and red tea extracts were prepared. Reaction detection was used for on-line determination of free radicals of 2,2-diphenyl-1- picrylhydrazil (DPPH) binding by high performance liquid chromatography.
Źródło:
Ars Separatoria Acta; 2007, 5; 27-33
1731-6340
Pojawia się w:
Ars Separatoria Acta
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Karotenoidy rola biologiczna i występowanie w owocnikach grzybów
Biological function of carotenoids and their occurrence in the fruiting bodies of mushrooms
Autorzy:
Muszyńska, Bożena
MASTEJ, Małgorzata
SUŁKOWSKA – ZIAJA, Katarzyna
Powiązania:
https://bibliotekanauki.pl/articles/1033726.pdf
Data publikacji:
2016
Wydawca:
Zakład Opieki Zdrowotnej Ośrodek Umea Shinoda-Kuracejo
Tematy:
"antioxidant activity"
"carotenoids"
"edible mushrooms"
"β
β-carotene"
Opis:
Due to the valuable properties of carotenoidsthe interest in new methods of obtaining them is still increasing. For this purpose, since the 60s of the twentieth century, scientists conducted numerous studies to recognize the processes in which carotenoids could be produced . Carotenoids, revealing a strong antioxidant activity, act as free radical scavengers. These compounds can support many beneficial processes such as the stimulation of the immune system, the modulation of intracellular signaling pathways, the regulation of the cell cycle and apoptosis as well as theregulation of growth factors. Carotenoids were determined by spectrophotometric analysis in the following fungal species: Leucopaxillus giganteus, Sarcodon imbricatus, Lactarius piperatus, Lactarius deliciosus, Agaricus arvensis, Agaricus bisporus, Agaricus romagnesii, Agaricus silvaticus, Agaricus silvicola, Hypholoma fasciculare, Calocybe gambosa, Craterellus cornucopioides, Marasmius oreades. High performance liquid chromatography (HPLC) coupled with a UV detector detected β,β-carotene in Agaricus bisporus, Polyporus squamosus, Lepista nuda, Russula delica, Verpa conica, Pleurotus ostreatus and Hypsizgus marmoreus. β-carotene and lycopene were also found in three wild species of edible mushrooms: Leucopaxillus giganteus, Sarcodon imbricatus and Agaricus arvensi. These compounds were isolated in several species of the family Cantharellus as well. One example is Cantharellus cibarius, which contains mainly β,β-carotene and minor amounts of lycopene, α-carotene and other carotenoids, which may be δ – and γ – isomers.
Źródło:
Medicina Internacia Revuo; 2016, 27, 107; 113-122
0465-5435
Pojawia się w:
Medicina Internacia Revuo
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
BIOLOGICAL ACTIVITY AND POLYPHENOL CONTENT IN SELECTED HERBAL TEA BLENDS USED IN DIABETES
Autorzy:
Bylka, Wiesława
Studzińska-Sroka, Elżbieta
Czapska, Izabela
Powiązania:
https://bibliotekanauki.pl/articles/895583.pdf
Data publikacji:
2019-12-29
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
antioxidant activity
Herbal blends
Antidiabetes
α-Glucosidase inhibition
Opis:
This study aimed to evaluate the antioxidant properties, α -glucosidase inhibitory activity, and the total content of polyphenols and flavonoids in the selected antidiabetic herbal blends (1-6), used traditionally in diabetes. The strongest antioxidant activity (DPPH and CUPRAC) was observed in extracts from blends 1 and 6 (IC50 <70 μg/ml, IC0,5 <110 μg/ml, respectively). Extracts from these blends also contained most of the polyphenolic compounds (>40 mg GAE/g), had a high content of flavonoids (6 - 10.96 mg QE/g, 1 - 7.51 mg QE/g) and the highest α-glucosidase inhibiting capacity (for 1 >90%, for 6 >90% and 5,55%, while for acarbose 1.76% and 0.93% at the 100 μg/ml and 10 μg/ml, respectively).The antioxidant activity of 1 and 6 correlated with the content of polyphenols and α-glucosidase inhibitory properties and indicates the existence of this mechanism in supporting the treatment of type 2 diabetes and diabetic complications by the above preparations.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2019, 76, 6; 1037-1042
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Total Phenolic, Flavonoid Contents and Antioxidant Activities of Honey and Propolis Collected from the Region of Laghouat (South of Algeria)
Autorzy:
Bakchiche, Boulanouar
Habati, Mounir
Benmebarek, Ahmed
Gherib, Abdelaziz
Powiązania:
https://bibliotekanauki.pl/articles/1114189.pdf
Data publikacji:
2017
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Antioxidant Activity
DPPH
FRAP
Honey
Phenolic Extracts
Propolis
Opis:
The aim of this study was to determine total phenolic and flavonoid contents and to evaluate the antioxidant activities of two honeys and one propolis sample, collected from the region of Laghouat (South of Algeria). Total phenolic content were determined by using Folin-Ciocalteu reagent as gallic acid equivalent, while flavonoids content was assessed by means of the AlCl3 method as Rutin equivalent. Antioxidant activities of the honeys and propolis were examined by two different methods, namely, scavenging of free radical 2,2-diphenyl-1-picrylhydrazyl and reducing power. The antioxidant activities were compared with standard antioxidants such as Ascorbic acid, BHT and Trolox. The highest level of phenolic was 2385 mg Gallic acid per 100g sample, the highest level of flavonoid was 379 mg Rutin per 100g sample, while the highest protein content was 1177 mg per 100g sample, DPPH (0.026 mg/ml) and TEAC (0.0015) were detected especially in the propolis sample, indicating that it holds good antioxidant properties. A strong positive correlation was found between phenolics, flavonoids, DPPH and TEAC, indicating that in addition to total phenolic content, flavonoid and protein concentrations are good indicators of the antioxidant potential of propolis and honey.
Źródło:
World News of Natural Sciences; 2017, 11; 91-97
2543-5426
Pojawia się w:
World News of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phytochemical Screening, Antioxidant and Antimicrobial Activities of Indoneesiella echioides (L.) Nees Leaves
Autorzy:
Elaiyaraja, A.
Chandramohan, G.
Mariajancyrani, J.
Jayabharathi, G.
Powiązania:
https://bibliotekanauki.pl/articles/1193940.pdf
Data publikacji:
2015
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Antimicrobial activity
Antioxidant activity
Indoneesiella echioides
Phytochemical screenings
Opis:
Indoneesiella echioides (or) Andrographis echioides (L) Nees is an important herb widely distributed in south India. This is commonly known as False Water willow. Indoneesiella echioides (L) Nees is a traditional Indian medicine; the whole plant is highly medicinal value such as the leaf juice of this plant is used to cure fever. The plant was extracted using n-hexane, chloroform, ethyl acetate, acetone, butanol, ethanol and methanol. The present study was to be determined the preliminary phytochemical screening, antioxidant and antimicrobial activities of Indoneesiella echioides (L) Nees leaves.
Źródło:
World Scientific News; 2015, 21; 51-63
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bioactive properties of elderflowers (Sambucus nigra L.)
Autorzy:
Młynarczyk, Karolina
Walkowiak-Tomczak, Dorota
Powiązania:
https://bibliotekanauki.pl/articles/1178436.pdf
Data publikacji:
2017
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Sambucus nigra L.
antioxidant activity
elderflower
phenolic compounds
Opis:
Elderflower is a valuable herbal raw material widely used in food, pharmaceutical and cosmetic industry. It is a rich source of bioactive compounds, such as polyphenols (e.g. chlorogenic acid, rutin, quercetin), that are responsible for their health benefits. Elderberry flowers demonstrate mainly diaphoretic, antipyretic, diuretic, antibacterial and anti-inflammatory properties and have been used in folk medicine as remedy for various ailments and diseases. The aim of the study was to evaluate selected bioactive properties of fresh and dried elderberry flowers, depending on the origin. Flowers were collected from three locations of wild elderberry shrubs and from three cultivars (Sampo, Haschberg, Samyl) growing on plantation. Methanolic extracts of fresh and dried flowers were analyzed in terms of the antioxidant activity using ABTS radical method and the total phenolic content by Folin-Ciocalteau reagent method. The results were statistically analyzed by Anova in Statistica 12.5 program. The obtained results indicate that drying process causes a deterioration of bioactive properties of elder flowers. Fresh flowers demonstrated significantly higher antioxidant activity as well as higher total phenolic content than dried flowers. Furthermore, flowers of wild elderberry differed from flowers of cultivated elderberry. In most cases, flowers of cultivars showed higher values of analyzed parameters compared to the wild elder flowers. The highest average antioxidant activity and the highest average content of total polyphenols was found in flowers of Sampo cultivar.
Źródło:
World Scientific News; 2017, 73; 114-118
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of apple and rosehip pomaces on colour, total phenolics and antioxidant activity of corn extruded snacks
Autorzy:
Drożdż, W.
Tomaszewska-Ciosk, E.
Zdybel, E.
Boruczkowska, H.
Boruczkowski, T.
Regiec, P.
Powiązania:
https://bibliotekanauki.pl/articles/778687.pdf
Data publikacji:
2014
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
apple pomace
rosehip pomace
extrusion
polyphenols
antioxidant activity
Opis:
Extrusion cooking technology was applied for obtaining corn extrudates fortifi ed with various level (10–20%) of rosehip pomace powder or apple pomace powder. The total polyphenols content, antioxidant activities (ABTS), organoleptic properties and colour of the extrudates were determined. Pomace addition increased the level of total polyphenols content and antioxidant activity in obtained corn – pomace extrudates, especially in samples enriched with rosehip pomace. Extrudates with 20% of rosehip pomace addition characterized the highest polyphenols content and antioxidant activity. Only the slight decrease of some quality features – shape and size, taste and fl avour, structure and colour of obtained extrudates was observed. Sample with fruit pomace addition showed increasing consistency evaluation. The extruded products by utilising fruit by-products got good evaluation of panelists and can be an excellent source of bioactive compounds in the daily human diet.
Źródło:
Polish Journal of Chemical Technology; 2014, 16, 3; 7-11
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
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