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Tytuł:
Fatty Acids Analysis and Antioxidant Activity of a Lipid Extract obtained from Mercurialis annua L. grown wildly in Jordan
Autorzy:
Al-Douri, Nedhal A.
Shakya, Ashok K.
Powiązania:
https://bibliotekanauki.pl/articles/895262.pdf
Data publikacji:
2019-04-30
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
fatty acid methyl ester (FAME)
GC-FID
Mercurialis annua L
DPPH radical scavenging activity
β-carotene bleaching assay
NO radical scavenging activity
Opis:
Aerial parts of Mercurialis annua L. were used in the present study, and fatty acid content in lipid extract was determined using GC-FID. The major fatty acids identified were α–linolenic acid (20.3%), heptadecanoic acid (12.8%), palmitic acid (11.9%), pentadecanoic acid (11.7%), cis-10-pentadecenoic acid (11.2%), linoleic acid (7.7%), tridecanoic Acid (4.6%), stearic (4.4%), cis-11,14-eicosadienoic acid (3.8%), beside of minor fatty acids (palmitoleic acid, cis-13,16-docosadienoic acid, arachidic acid, behenic acid, cis-10-heptadecenoic acid and myristic acid). Antioxidant properties of the extract were determined via DPPH radical scavenging, β-carotene bleaching assay and NO radical scavenging assay. The extract produced significant antioxidant activity in-vitro. The data shown here may broaden our knowledge on composition and antioxidant activity of lipid constituents from Mercurialis annua L.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2019, 76, 2; 275-281
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Redox state modulation in rice and its implications for plant development and stress responses
Autorzy:
Caverzan, A.
Ribeiro, C.
Lazzarotto, F.
Passaia, G.
Rosa, S.
Garighan, J.
Piovesana, M.
Carvalho, F.
Albenisio, J.
Margis, R.
Margis-Pinheiro, M.
Powiązania:
https://bibliotekanauki.pl/articles/79908.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
conference
reactive oxygen species
scavenging enzyme
detoxification
redox state
rice
plant development
stress response
plant cell
biochemical property
antioxidative enzyme
ascorbate peroxidase
glutathione peroxidase
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2013, 94, 2
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Involvement of ROS and its scavenging enzymes in the response of dormant Avena fatua L. caryopses to karrikinolide (KAR1)
Autorzy:
Cembrowska-Lech, D.
Kepczynski, J.
Powiązania:
https://bibliotekanauki.pl/articles/80050.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
conference
reactive oxygen species
scavenging enzyme
Avena fatua
caryopsis
germination
dehydrogenase activity
amylase
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2013, 94, 2
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antioxidative Capacity of Soyfoods and Soy Active Compounds
Autorzy:
Chitisankul, Wanida T.
Shimada, Kazuko
Tsukamoto, Chigen
Powiązania:
https://bibliotekanauki.pl/articles/2019471.pdf
Data publikacji:
2022-03-01
Wydawca:
Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
Tematy:
soybean
ORAC
isoflavone
peroxyl radical scavenging
soy saponin
Opis:
Soyfood isoflavones and soyasaponins are the effective compounds relating to their health-promoting properties. Their chemical structure plays an important role in their antioxidative activity. Thus, six isoflavones and four soyasaponins that are targeted in soyfood were evaluated for their peroxyl radical scavenging capacities by the hydrophilic-oxygen radical absorbance capacity (H-ORAC) method. The antioxidant capacity of non-fermented and fermented soyfoods was also determined by the same method. The results revealed that isoflavones showed higher peroxyl radical scavenging capacities than soyasaponin, with their activities found to depend on their chemical structure. The aglycone isoflavones promoted higher H-ORAC values than glycoside and malonyl glycoside isoflavones, respectively. On the other hand, DDMP saponin promoted a higher H-ORAC value than its derived compound, group B saponin, and the aglycone soyasaponin. In the case of soyfoods, fermented soyfoods had higher antioxidative capacity that the non-fermented ones, especially the long-term fermented products. Soybean-koji miso presented the highest H-ORAC value, followed by natto, soy sauce, and tempeh. Moreover, lightness (L*) of miso and soy sauce showed a negative correlation with H-ORAC value probably due to browning substances which might derive from the amino-carbonyl reaction. Considering the high antioxidant capacity of fermented soyfoods, it might relate to aglycone isoflavones which promote strong radical scavenging capacity. Thus, fermented soyfoods, especially miso and natto, could be considered as health-promoting foods.
Źródło:
Polish Journal of Food and Nutrition Sciences; 2022, 72, 1; 101-108
1230-0322
2083-6007
Pojawia się w:
Polish Journal of Food and Nutrition Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of extraction technique on yield and antioxidant activity of extracts from Moringa oleifera leaf
Autorzy:
Dzięcioł, Małgorzata
Powiązania:
https://bibliotekanauki.pl/articles/778776.pdf
Data publikacji:
2020
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
Moringa oleifera
extracts
antioxidant activity
DPPH radical scavenging method
total phenolic content.
Opis:
The article presents research on the exploring of extraction process of biologically active substances from the leaves of the Moringa oleifera tree using ethanol. Ethanolic extracts were obtained using three different techniques: maceration with shaking, ultrasound-assisted extraction and extraction in Soxhlet apparatus, in different time variants: 1, 2 and 4-hours. After solvent evaporating and drying, the yields of dry extracts obtained in particular processes were calculated. The antioxidant activity of extracts was analyzed spectrophotometrically using DPPH radical scavenging method, and total phenolic content (TPC) was determined by Folin-Ciocalteu method. By means of gas chromatography with mass selective detector (GC-MS), 11 biologically active compounds present in ethanolic extracts were identified, among which α-tocopherol had the greatest share. Based on the results, the influence of the extraction technique and time on the yield and antioxidant activity of M. oleifera leaf extracts were discussed.
Źródło:
Polish Journal of Chemical Technology; 2020, 22, 4; 31-35
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A comparative study of the antioxidant activity and phytochemical composition of leaves extract between three varieties of date palm tree
Autorzy:
Eddine, L. S.
Ladjel, S.
Mohamed, O. M.
Powiązania:
https://bibliotekanauki.pl/articles/412430.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Phoenyx dactylifera
polyphenol
DPPH radical-scavenging activity
reducing power
antimicrobial
south Algeria
Opis:
The date palm (Phoenyx dactylifera) consisted, for the people of southern Algeria, as tree of providence. Dates and their extracts are also used for many centuries as a medicine against allergy, inflammation, constipation and gastro-protective; they also have a high antibacterial and antioxidant activity. However, no studies are conducted to evaluate the extract from the leaves of date palm (Phoenyx dactylifera) in point of view of phytochemical composition, antimicrobial and the antioxidant activity. In this study, we have determined the phenolic compounds, antioxidant and antimicrobial activity of methanolic extracts from three varieties of leaves tree. According to the results the leaves extracts have very important values for polyphenols (215.24 to 156.46 mg GAE / g DW) and high antioxidant activity (324. 45 to 206.21 mg GAE / g DW), Diphenyl-1 picrylhydrazyl radical-scavenging activity (IC50 = 2.98 to 4.83 μg / ml); also the three extracts reveal a considerable antimicrobial potency and antifungal considerable activity, the diameter of inhibition is 35.2 to 39.5 mm (concentration 50 mg/ml) for Candida albicans ATCC 90026.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 9, 2; 162-171
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
GC-MS Analysis and Biological activity of Essential Oil of Fruits, Needles and Bark of Pinus pinea grown wildly in Jordan
Autorzy:
Halloum, Baha
Shakya, Ashok K.
Elagbar, Zaha A.
Naik, Rajashri R.
Powiązania:
https://bibliotekanauki.pl/articles/895316.pdf
Data publikacji:
2019-10-30
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
antibacterial activity
essential oils
antioxidant activity
DPPH radical scavenging activity
β-carotene bleaching assay
Pinus pinea
Opis:
Essential oils from needles, fruits and bark was extracted from Pinus pinea L. (stone pine) grown wildly in Jordan. The chemical composition, antibacterial activity, antioxidant activity of essential oils was evaluated. The chemical compositions were identified using Gas-Chromatography-Mass spectrometry (GC-MS) and retention Indices (Van den Dool & Kratz). The results show that the essential oil obtained from needles composed mainly of Guaiol (12.7%), limonene (11.42%), and β-caryophyllene (7.61%), while fruit contains limonene (32.56%), and α-pinene (6.78%). The essential oils from barks were rich in β-caryophyllene (16.51%), limonene (14.83%), caryophyllene oxide (11.83%), and longifolene (7.51%). In vitro, antibacterial activity of the essential oil samples was evaluated using agar-well diffusion method against three different strains of bacteria (Gram¬-positive bacteria: Staphylococcus aureus and Gram-negative bacteria: Klebsiella pneumoniae and Escherichia coli). The results showed that essential oil showed appreciable antibacterial activity against S. aureus. The essential oil from fruit exhibited weak antibacterial activity against E. coli and K. pneumoniae. Essential oils of P. pinea showed appreciable antioxidant activity in-vitro.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2019, 76, 5; 825-831
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Plants take action to mitigate salt stress: Ask microbe for help, phytohormones, and genetic approaches
Autorzy:
Hewedy, Omar A.
Mahmoud, Ghada Abd-Elmonse
Elshafey, Naglaa F.
Khamis, Galal
Karkour, Ali M.
Abdel Lateif, Khalid S.
Amin, Basma H.
Chiab, Nour
El-Taher, Ahmed M.
Elsheery, Nabil I.
Powiązania:
https://bibliotekanauki.pl/articles/2174285.pdf
Data publikacji:
2022
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
Bacillus
ion homeostasis
osmoprotectants
osmotic stress
photosynthesis
ROS scavenging
Opis:
Global agriculture is a pivotal activity performed by various communities worldwide to produce essential human food needs. Plant productivity is limited by several factors, such as salinity, water scarcity, and heat stress. Salinity significantly causes short or long-term impacts on the plant photosynthesis mechanisms by reducing the photosynthetic rate of CO2 assimilation and limiting the stomatal conductance. Moreover, disturbing the plant water status imbalance causes plant growth inhibition. Up-regulation of several plant phytohormones occurs in response to increasing soil salt concentration. In addition, there are different physiological and biochemical mechanisms of salt tolerance, including ion transport, uptake, homeostasis, synthesis of antioxidant enzymes, and osmoprotectants. Besides that, microorganisms proved their ability to increase plant tolerance, Bacillus spp. represents the dominant bacteria of the rhizosphere zone, characterised as harmless microbes with extraordinary abilities to synthesise many chemical compounds to support plants in confronting salinity stress. In addition, applying arbuscular mycorrhizal fungi (AMF) is a promising method to decrease salinity-induced plant damage as it could enhance the growth rate relative to water content. In addition, there is a demand to search for new salt-tolerant crops with more yield and adaptation to unfavourable environmental conditions. The negative impact of salinity on plant growth and productivity, photosynthesis, stomatal conductance, and changes in plant phytohormones biosynthesis, including abscisic acid and salicylic acid, jasmonic acid, ethylene, cytokinins, gibberellins, and brassinosteroids was discussed in this review. The mechanisms evolved to adapt and/or survive the plants, including ion homeostasis, antioxidants, and osmoprotectants biosynthesis, and the microbial mitigate salt stress. In addition, there are modern approaches to apply innovative methods to modify plants to tolerate salinity, especially in the essential crops producing probable yield with a notable result for further optimisation and investigations.
Źródło:
Journal of Water and Land Development; 2022, 55; 1--16
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New information on scavenging and selective feeding behaviour of tyrannosaurids
Autorzy:
Hone, D.W.E.
Watabe, M.
Powiązania:
https://bibliotekanauki.pl/articles/20999.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleontology
new information
scavenging
feeding behaviour
tyrannosaurid
Dinosauria
Theropoda
Tarbosaurus
paleoecology
carnivore
predation
fossil record
Opis:
Feeding traces for carnivorous theropod dinosaurs are typically rare but can provide important evidence of prey choice and mode of feeding. Here we report a humerus of the hadrosaurine Saurolophus which was heavily damaged from feeding attributed to the giant tyrannosaurine Tarbosaurus. The bone shows multiple bites made in three distinctive styles termed “punctures”, “drag marks” and “bite−and−drag marks”. The distribution of these bites suggest that the animal was actively selecting which biting style to use based on which part of the bone was being engaged. The lack of damage to the rest of the otherwise complete and articulated hadrosaur strongly implies that this was a scavenging event, the first reported for a tyrannosaurid, and not feeding at a kill site.
Źródło:
Acta Palaeontologica Polonica; 2010, 55, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rozwinięcie metody analizy numerycznej wymiany ładunku w silnikach o tłokach przeciwbieżnych
Development of the numerical scavenging process analysis in opposed-piston engines
Autorzy:
Kalke, J.
Mazuro, P.
Sulikowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/133702.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Naukowe Silników Spalinowych
Tematy:
wymiana ładunku
silnik o tłokach przeciwbieżnych
skryptowanie
sprawność
scavenging
opposed-piston engine
scripting
efficiency
Opis:
Moc i sprawność całkowita silników dwusuwowych jest silnie zależna od sprawności wymiany ładunku, dlatego też optymalizacja tego procesu jest krytyczna z punktu widzenia wydajności. Głównym celem tego artykułu jest pokazanie potencjału łączenia ze sobą różnych narzędzi inżynierskich w celu znacznego przyspieszenia fazy koncepcyjnej weryfikacji różnych systemów wymiany ładunku. Proponowany algorytm postępowania używa różnorakich języków programowania do łączenia komercyjnych (w tym przypadku Ansys Workbench, Siemens NX, MathWorks Matlab, Microsoft Excel) i niekomercyjnych pakietów (Cantera) by uzyskać najważniejsze informacje tak wcześnie jak jest to możliwe. Proponowane narzędzie obsługuje model 0-wymiarowy procesu spalania (z zadanym stężeniem gazów wylotowych), podziału geometrii i dyskretyzacji przestrzennej, zautomatyzowanego ustawiania programu obliczeniowego i postprocesora do danych numerycznych, przygotowanych specjalnie dla rozrządu sterowanego tłokami. Przeprowadzono prostą ocenę zaoszczędzonego czasu dzięki zaproponowanej metodzie postępowania. Ostania część jest krytycznym podsumowaniem zaproponowanej metody i wskazuje pewne ciekawe kierunki rozwoju takie jak kosymulacja z programami 1D oraz bardziej zaawansowane modelowanie spalania.
The power and overall efficiency of two-stroke engines are strongly dependent by scavenging efficiency, thus optimization of this process is vital to performance. Main aim of this article is to show the potential of combining different engineering tools to substantially speed-up the conception verification phase of various scavenging systems. The suggested algorithm uses a variety of programming languages to interconnect commercial (in this case Ansys Workbench, Siemens NX, MathWorks Matlab, Microsoft Excel) and non-commercial packages (Cantera) to get the most important information as soon as possible. Presented tools cover 0-D combustion process model (with desired exhaust gases concentration), geometry division and meshing, automated solver-setting and numerical-data postprocessor, prepared especially for piston ported valves. A simple evaluation of time savings by using proposed method was conducted. Last part is a critical sum-up of presented method and pointing out some interesting directions of development, concerning co-simulation with 1D software and more sophisticated combustion modeling.
Źródło:
Combustion Engines; 2015, 54, 3; 511-519
2300-9896
2658-1442
Pojawia się w:
Combustion Engines
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of biologically active substances on antioxidant activity in rapeseed oil tested in accelerated oxidative process
Wpływ dodatku wybranych substancji biologicznie czynnych na aktywność antyoksydacyjną oleju rzepakowego poddanego przyspieszonemu procesowi autooksydacji
Autorzy:
Kania, M.
Michalak, M.
Gogolewski, M.
Powiązania:
https://bibliotekanauki.pl/articles/833608.pdf
Data publikacji:
2005
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
biologically active substance
antioxidant activity
rapeseed oil
accelerated oxidative process
tocopherol
free radical scavenging
DPPH method
menadione K3
ubiquinon Q10
beta-carotene
quercetin
coenzyme Q10
vegetable oil
Źródło:
Rośliny Oleiste - Oilseed Crops; 2005, 26, 1
1233-8273
Pojawia się w:
Rośliny Oleiste - Oilseed Crops
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nutritional Properties, Antioxidant and Antihaemolytic Activities of the Dry Fruiting Bodies of Wild Edible Mushrooms Consumed by Ethnic Communities of Northeast India
Autorzy:
Kokoti, Merilin
Hazarika, Dibiya J.
Parveen, Assma
Dullah, Samim
Ghosh, Alokesh
Saha, Dipankar
Barooah, Madhumita
Boro, Robin Ch.
Powiązania:
https://bibliotekanauki.pl/articles/2019175.pdf
Data publikacji:
2021-12-01
Wydawca:
Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
Tematy:
antihaemolytic activity
basidiomycota
radical scavenging activity
nutrients
organic acids
phenolic acids
Opis:
A variety of cultivated mushrooms in Northeast India are well known for their taste, nutritional and medicinal benefits. Many wild-growing mushrooms are also consumed due to their exotic flavours and tastes; however, the scientific exploration of their nutritional and bioactive properties is still negligible. In the present study, the 32 wild edible mushroom samples of 11 species collected from different parts of Northeast India were evaluated for their proximate composition, mineral and vitamin (ascorbic acid and riboflavin) contents, antioxidant and antihaemolytic activity, and profiles of organic and phenolic acids. Lentinus sajor-caju and Lentinus squarrosulus had the highest carbohydrate content (49.80 g/100 g dry weight (d.w.) and 46.36 g/100 g d.w., respectively), crude protein content (20.72 g/100 g d.w. and 20.54 g/100 g d.w., respectively) and a considerable content of minerals. The highest fat content was determined in Lentinus velutinus (7.17 g/100 g d.w.). Among the minerals, potassium was found as the most abundant in all the samples. The extracts of L. sajor-caju, L. squarrosulus, and Pleurotus pulmonarius were characterized by the highest antioxidant activity, while these of L. sajor-caju, Pleurotus ostreatus, P. pulmonarius and Agaricus bisporus showed the highest antihaemolytic potential. The HPLC analysis allowed determining the high contents of ascorbic acid and a few organic and phenolic acids such as lactic acid, gallic acid, 3,4-dihydroxybenzoic acid and trans-cinnamic acid in the tested mushrooms. Other compounds viz. citric acid, caffeic acid, riboflavin, vanillic acid, pyruvic acid, and p-coumaric acid were detected with variations. This study established the nutritional and health-promoting benefits of wild edible mushrooms of Northeast India region for consumption as functional foods in human diet.
Źródło:
Polish Journal of Food and Nutrition Sciences; 2021, 71, 4; 463-480
1230-0322
2083-6007
Pojawia się w:
Polish Journal of Food and Nutrition Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The effect of LED lighting on some antioxidants parameters in lambs lettuce
Autorzy:
Kolton, A.
Wojciechowska, R.
Dlugosz-Grochowska, O.
Powiązania:
https://bibliotekanauki.pl/articles/80123.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
conference
light emitting diode
lighting
sodium lamp
antioxidant parameter
reactive oxygen species
lamb
lettuce
catalase activity
peroxidase activity
phenolic compound
ascorbic acid
radical scavenging activity
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2013, 94, 2
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
THE INFLUENCE OF STORAGE TEMPERATURE AND UV-IRRADIATION ON FREE RADICAL SCAVENGING PROPERTIES OF ETHANOLIC EXTRACTS OF PROPOLIS
Autorzy:
Komosińska-Vassev, Katarzyna
Olczyk, Paweł
Ramos, Paweł
Mencner, Lukasz
Derkacz, Alicja
Waluga, Ewa
Krysik, Katarzyna
Olczyk, Krystyna
Pilawa, Barbara
Powiązania:
https://bibliotekanauki.pl/articles/895577.pdf
Data publikacji:
2018-01-31
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
EPR spectroscopy
DPPH
free radical scavenging
ethanol extracts of propolis
UV-irradiation
Opis:
The free radical scavenging activity of ethanolic extracts of propolis (EEP) at the concentrations of 3%, 7%, and 10% was examined. The impact of storage temperature and exposure to ultraviolet (UV) light on the interactions of extracts of propolis with the model DPPH free radicals was also determined. The quenching of an X-band electron paramagnetic resonance spectra of DPPH free radicals by the extracts stored at room temperature, heated at the temperature of 50 oC and exposed to UV-irradiation, were compared. The examined propolis ethanolic extracts revealed an antioxidative character. The storage of the samples at a higher temperature (50 oC) caused a decrease of the scavenging activity equaling to 7% and 10% EEP. UV-irradiation of the 3% EEP increased the quenching of DPPH free radical lines. The reverse effect was observed for the 7% and 10% propolis extracts. The 3% ethanolic extract of propolis is more stable for storage at 50ºC, and less than other analyzed EEP susceptible for UV-irradiation. Alterations of the antioxidative properties of the analyzed EEP and changes in the kinetics of their interactions with free radicals, indicate that 3%, 7%, and 10% propolis extracts should not be exposed to the temperature of 50 oC and UV-irradiation.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2018, 74, 6; 1833-1840
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of 2,5-dichloro-1,4-benzoquinone on jack bean urease activity. Inhibitory effect, total reducing capacity and DPPH radical scavenging activity
Autorzy:
Kot, Mirosława
Olech, Zofia
Powiązania:
https://bibliotekanauki.pl/articles/1039867.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
reducing capacity
inhibition
urease
Folin-Ciocalteu method
2,5-dichloro-1,4-naphthoquinone
DPPH scavenging activity
Opis:
Inhibition of jack bean activity by 2,5-dichloro-1,4-benzoquinone (DCBQ) was studied in phosphate buffer, pH 7.0. It was found that DCBQ acted as a strong, time and concentration dependent inactivator of urease. Under the experimental conditions obeyed the terms of pseudo-first-order reaction, urease was totally inactivated. Application of Wilson-Kitz method proved that the urease-DCBQ interaction followed a simple bimolecular process and the presence of intermediate complex was undetectable. The determined second order rate constant of the inactivation was 0.053 (μM min)-1. Thiols such as l-cysteine, glutathione and dithiothreitol (DTT) protected urease from inhibition by DCBQ but DCBQ-modified urease did not regain its activity after DTT application. The thiol protective studies indicated an essential role of urease thiol(s) in the inhibition. The irreversibility of the inactivation showed that the process was a result of a direct modification of urease thiol(s) by DCBQ (DCBQ chlorine(s) substitution). The decomposition of DCBQ in aqueous solution at natural light exposure was monitored by visible spectrophotometry, determination of the total reducing capacity (Folin-Ciocalteu method) and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging ability. The DCBQ conversion resulted in a decrease of the inhibition power and was well correlated with the increase of the total reducing capacity and DPPH scavenging ability. These findings were attributed to DCBQ transformation by photolysis and the hydrolysis effect was found to be negligible.
Źródło:
Acta Biochimica Polonica; 2011, 58, 4; 627-633
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 29

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