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1

Total antioxidant capacity and total polyphenol content of the selected plant products measured by DPPH, ABTS and Folin-Ciocalteu methods

100%
Czlapka-Matyasik M., Gramza-Michałowska A., Fejfer M., Jeszka J.
Polish Journal of Food and Nutrition Sciences
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2011
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tom 61
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nr Suppl.1
2

Commodity feature and antiradical capacity of Pu Erh tea leaves available on Polish market

84%
Gramza-Michalowska A., Kulczynski B., Jankowiak J., Grden M.
Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology
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2017
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tom 20
|
nr 2
3

A comparison of ABTS and DPPH methods for assessing the total antioxidant capacity of human milk

84%
Martysiak-Zurowska D., Wenta W.
Acta Scientiarum Polonorum. Technologia Alimentaria
|
2012
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tom 11
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nr 1
Introduction. The Total Antioxidant Capacity (TAC) of human milk reflects the concentration and the activity of many components which prevent oxidative degradation of fats and proteins. This study compares the effectiveness of ABTS and DPPH tests with regard to the recovery, precision and sensitivity (detection and quantification limit) of (TAC) values in human milk. Material and methods. TAC values were determined in twenty five samples of human milk obtained from healthy mothers, residents of Gdańsk, on the 14,h day postpartum. Results. The average TAC of human milk determined by ABTS assay was 19.61 ±3.311 mg TE (Trolox Equivalents)/100 cm3, the average values obtained by the DPPH assay reached 9.95 ±4.36 mg TE/100 cm3. For each milk sample the TAC determined by the ABTS test was significantly higher than the values produced by the DPPH test. The above findings can be attributed to the presence of substances whose spectra overlap with DPPH’ spectra. ABTS test was characterised by a higher sensitivity and repeatability of the determination of TAC in human milk compared to the DPPH test. Conclusions. Comparing the calculated values for the validation parameters of both methods and taking into account the solubility of DPPH only in polar matrices, slower reaction of selected antioxidants with DPPH radical, and the presence in human milk constituents absorbing electromagnetic radiation in the absorption of DPPH be assumed that the ABTS test is more appropriate method of determining of TAC in breast milk.
4

Optimizing method for the measurement of insoluble antioxidants in foods

84%
Cejpek K., Banacka E., Konecny M., Velisek J.
Polish Journal of Food and Nutrition Sciences
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2011
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tom 61
|
nr Suppl.1
5

Antioxidant potential of various extracts from 5 common European mosses and its correlation with phenolic compounds

84%
Smolinska-Kondla D., Zych M., Ramos P., Wacławek S., Stebel A.
Herba Polonica
|
2022
|
tom 68
|
nr 2
6
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Antioxidant activity of flavonoids of different polarity, assayed by modified ABTS cation radical decolorization and EPR technique

84%
Pawlak K., Bylka W., Jazurek B., Matlawska I., Sikorska M., Manikowski H., Bialek-Bylka G.
Acta Biologica Cracoviensia. Series Botanica
|
2010
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tom 52
|
nr 1
97-104
Modified ABTS cation radical decolorization assay and EPR technique were applied to screen the antioxidant activity of three flavonoids with different polarity: 7-O-β-[2-O-feruloyl-β-glucuronopyranosyl (1→2) glucuronopyranoside] (tricine), 4'-methoxy-5,7-dihydroxyflavone 6-C-β-glucopyranoside (isocytisoside) and I 3' II 8 biapigenine (amentoflavone), with nonpolar all-trans β-carotene used as standard carotenoid molecule. The ABTS [2,2'- azino-bis(3-ethylbenzthiazoline-6-sulphonic acid] cation radical decolorization assay was modified as follows: (1) measurements extended up to 8 days after preparation, (2) method adapted for flavonoids with different polarity and β-carotene, (3) concentrations in the 0.01-10 μM range of both trolox and antioxidants in order to use the same experimental conditions for both this technique and EPR measurement.
7
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Comparison of antioxidant activities of fractionated extracts from seedlings and herb of Chelidonium majus L. using DPPH, ABTS and FRAP methods

67%
Ozarowski M., Kujawski R., Mikolajczak P., Gryszczynska A., Pietrowiak A., Bialas W., Baraniak J., Gorska-Paukszta M., Buchwald W., Kedzia B., Krajewska-Patan A., Seremak-Mrozikiewicz A.
Herba Polonica
|
2016
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tom 62
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nr 4
Introduction: Our study is a part of a trend of studies on the antioxidative properties of Chelidonium majus extracts or their fractions suggesting that antioxidant activities may depend on total flavonoid and/or alkaloid contents. Objective: This study focused on the examination of antioxidative activities of full water extract, non-protein fraction and protein fraction of the extract from aerial parts of mature plants and young seedlings. Methods: Total flavonoid and alkaloid contents were evaluated by spectrometric methods. Quantitative determination of chelidonine, coptisine, sanquinarine, berberine was made by HPLCUV. The antioxidative activities were evaluated using (1) 2,2-diphenyl-1-picrylhydrazyl (DPPH), (2) 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging and (3) ferric reducing antioxidant power (FRAP) methods. Results: All concentrations of herb extracts exhibited higher antioxidant capacities than extract from seedlings. Two antioxidant tests (DPPH, FRAP) showed that full water extract from herb had the highest antioxidant activity, while its non-protein fraction and protein fraction showed lower antioxidant activity. It was found that the full water extract from herb contained the highest concentrations of flavonoids and alkaloids when compared with other samples. Conclusion: Our findings suggest that chelidonine and coptisine especially could be responsible for the observed changes in the extract antioxidant activity, because these alkaloids were determined in the highest concentration in full water extract from herb. It cannot be also excluded that the observed variables values between extracts and their fractions from herb or from seedlings may also be the result of interactions between flavonoids and other chemical compounds.
8
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Comparison of in vitro antioxidative activities of crude methanolic extracts of three species of Passiflora from greenhouse using DPPH, ABTS and FRAP methods

67%
Ozarowski M., Pietrowiak A., Gryszczynska A., De A.Chaves D. S., Krajewska-Patan A., Wielgus K., Seremak-Mrozikiewicz A.
Herba Polonica
|
2019
|
tom 65
|
nr 3
9

Evaluation of antioxidant activity of amaranth [Amaranthus cruentus] grain and by-products [flour, popping, cereal]

67%
Pasko P., Barton H., Folta M., Gwizdz J.
Roczniki Państwowego Zakładu Higieny
|
2007
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tom 58
|
nr 1
The objective of our study was evaluation antioxidant activity of Amaranthus cruentus grain and by-products (flour, cereals and popping). The evaluation was performed by FRAP, DPPH and ABTS methods. FRAP and ABTS assays gave comparable results, DPPH method gave lower values. Among by-products cereal had the highest activity as the least processed product. Additionally, antioxidant capacities of two cultivars of amaranth (varieties Aztek and Rawa) were compared and the influence of grain soaking on antioxidant properties was taken into account. It was found, that soaking decreased antioxidant activity of amaranth seed.
10

Antioxidant capacity, ascorbic acid and phenolics content in wild edible fruits

51%
Jablonska-Rys E., Zalewska-Korona M., Kalbarczyk J.
Journal of Fruit and Ornamental Plant Research
|
2009
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tom 17
|
nr 2
115-120
The studied material were the fruits of 7 wild species: dog rose (Rosa canina L.), blackberry (Rubus caesius L.), elderberry (Sambucus nigra L.), blueberry (Vaccinium myrtillus L.), blackthorn (Prunus spinosa L.), rowan (Sorbus aucuparia L.) and wild strawberry (Fragaria vesca L.). The fruits were subjected to an antioxidant activity assay (AA). Two methods were used: FRAP and ABTS. The fruit samples were also subjected to analyses for phenolics (recalculated onto gallic acid) by means of the Folin-Ciocalteau method. The fruit samples were subjected to vitamin C analyses as well, applying the Tilmans' method. Dog rose fruits were characterized by the largest antioxidant capacity - 127.78±1.85 mM Fe100 g-1 of fresh mass (FRAP method) and 38.75±0.33 ^M TEg-1 of fresh mass (ABTS method). At the same time, they con­tained the largest amounts of vitamin C - 1252.37±6.58 mg100 g-1 of fresh mass and phenolics - 3217.28±11.94 mg100 g-1 of fresh mass. Blackthorn, rowan and wild strawberry had the lowest antioxidant capacity of all the fruits studied. The examin­ation confirmed a high correlation between antioxidant capacity, and vitamin C and phenolics content in fruits.
11
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Total antioxidant capacity as an important element in the assessment of soil properties for the production of high-quality agricultural and horticultural raw materials with health-promoting properties

51%
Skwarylo-Bednarz B.
Acta Agrophysica
|
2019
|
tom 26
|
nr 2
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