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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Antioxidant capacity of thermally-treated buckwheat

100%
Zielinska D., Szawara-Nowak D., Michalska A.
Polish Journal of Food and Nutrition Sciences
|
2007
|
tom 57
|
nr 4
465-470
This paper reports the use of an in vitro chemiluminescent method, ORACFL and SOD-like activity assays for the evaluation of antioxidant capacity of the whole buckwheat and its products after hydrothermal treatment. Phosphate buffer (0.75 mmol/L, pH 7.4) and 80% methanol (v/v) were used for the preparation of extracts originated from untreated buckwheat, hydrothermally-processed whole buckwheat, and obtained light groat and hull from the treated whole buckwheat. The antioxidative capacities of water- (ACW) and lipid-soluble (ACL) compounds were investigated by a facile chemiluminescence assay using a Photochem® device. The superoxide dismutase-like activity (SOD-like activity) was evaluated as free radical scavenging activities of the extracts against superoxide anion radicals (O2 -􀀀) whereas Oxygen Radical Antioxidant Capacity (ORACFL) of the extracts was determined with the spectrofluorimetric assay. Moreover, the content of flavonoids in untreated buckwheat and its products after hydrothermal treatment was provided. The antioxidant capacity of the whole buckwheat before hydrothermal treatment evaluated with the chemiluminescence assay was formed mainly by lipid soluble antioxidants (ACL; 88.8 μmol Trolox/g d.m.) and only in part by the water soluble compounds (ACW; 5.1 μmol Trolox/g d.m.). The hydrothermal treatment of buckwheat whole grains caused a decrease in ACW and ACL by approximately 58% and 17%, respectively. The changes in the antioxidant capacity of untreated buckwheat and its products obtained after hydrothermal treatment were confirmed by the application of SOD and ORACFL methods. Antioxidant capacity of buckwheat material was related to changes in flavonoids composition provided by HPLC analysis.
2
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Elicitation with sodium silicate and iron chelate affects the contents of phenolic compounds and minerals in buckwheat sprouts

100%
Debski H., Wiczkowski W., Szawara-Nowak D., Horbowicz M.
Polish Journal of Food and Nutrition Sciences
|
2021
|
tom 71
|
nr 1
The study concerned the effect of elicitors on the contents of free flavonoids and phenolic acids, as well as their esters and glycosides, and contents of minerals in 7-day sprouts of common buckwheat. An aqueous solution containing a mixture of sodium silicate and Fe-EDTA (SIL-Fe) was compared with the same concentration of sodium silicate alone (SIL) and water (control). Phenolic compounds were analysed using an HPLC–MS/MS apparatus equipped with an ion-trap mass spectrometer, and analyses were conducted by multiple reaction monitoring of selected negative ions. The contents of macro- and microelements in sprouts were determined by the ICP-AES method, after sample mineralization in a mixture of HNO₃ and H₂O₂. The study showed that SIL-Fe influenced the accumulation of individual phenolics in buckwheat sprouts in different ways. Among the major flavonoids in the buckwheat sprouts treated with SIL-Fe, the content of free forms and esters of (-)-epicatechin and glycosides of quercetin as well as the total content of flavonoids decreased. Elicitation of buckwheat sprouts with SIL and SIL-Fe reduced the contents of calcium, potassium, copper, and zinc; however, the SIL-Fe treatment caused a 5-fold increase in iron content and a 2-fold increase in silicon content. The ratio of total flavonoids to the iron content of SIL-Fe-treated sprouts was 11.5, which was substantially lower than in the control, where it reached 64. The results of this study indicate that it is possible to produce buckwheat sprouts with a high content of flavonoids and fortified with iron, which may increase the availability of this element.
3

Antioxidant properties of buckwheat enhanced wheat breads

100%
Szawara-Nowak D., Zielinski H., del Castillo M. D.
Polish Journal of Food and Nutrition Sciences
|
2011
|
tom 61
|
nr Suppl.1
4
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Determination of the antioxidant activity of rutin and its contribution to the antioxidant capacity of diversified buckwheat origin material by updated analytical strategies

100%
Zielinska D., Szawara-Nowak D., Zielinski H.
Polish Journal of Food and Nutrition Sciences
|
2010
|
tom 60
|
nr 4
The antioxidant activity of rutin and selected common buckwheat-originated materials, namely groat, hull, flour and sprouts were measured against stable, non-biological radicals such as 2,2’-azinobis-(3-ethylbenzothiazoline-6-sulphonate) radical cation (ABTS•+) and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) using a spectrophotometric assay, against the key reactive oxygen intermediate – superoxide anion radical (O2 –•) with a photochemiluminescence assay (PCL) while reducing capacity was determined with the cyclic voltammetry method (CV). The antioxidant activity was presented independently of the techniques used as TEAC values and then the contribution of rutin to the antioxidant capacity of buckwheat material was calculated. The order of the antioxidant activity of rutin provided by the updated analytical strategy was as follows: CV = DPPH RSA > PCL > ABTS RSA. Buckwheat groat and hull represented low antioxidant capacity samples whilst that of sprouts was ranked as high antioxidant capacity one. The results showed a low contribution of rutin to the antioxidant capacity of buckwheat groat and hull. The highest contribution of rutin to the antioxidant capacity was noted in buckwheat sprouts, especially those produced in light. The specificity of the rank of methods used as CV = DPPH RSA > ABTS RSA > PCL was concluded since the lowest antioxidant gap was provided with CV and DPPH RSA whilst the highest one with ABTS RSA and PCL.
5
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Tocotrienols in three rye varieties: from the grain to the bread

88%
Zielinski H., Michalska A., Szawara-Nowak D., Wiczkowski W., Piskua M. K.
Polish Journal of Food and Nutrition Sciences
|
2007
|
tom 57
|
nr 4
441-446
In this study the contribution of tocotrienols to the total tocols of three varieties of rye grain (Amilo, Warko and Dańkowskie Złote), their morphological fractions, milling products and breads made from them was shown. Tocotrienols (a-T3, b-T3, g-T3) and tocopherols (a-T, b-T, g-T, d-T) were extracted with methanol and separated by HPLC. The study showed that the richest source of tocotrienols was the whole grain of Dańkowskie Złote followed by the whole grain of Warko and Amilo cultivars. The tocotrienols found in the whole grain of three rye cultivars were a-T3 and b-T3 while the pool of tocopherols was formed by a-T, b-T and small quantity of g-T. Tocotrienols found in the whole grain or in endosperm with embryo fraction contributed to more than 50% of total tocols, however those noted in pericarb with testa fraction were about of 90% of total tocols. The highest level of tocotrienols (a-T3 + b-T3) was noted in rye flours with extraction rate of 100% of the three cultivars. The milling process decreased contents of tocotrienols, however flours with extraction rate from 100 to 90% kept the T3/T ratio above one, whereas for flour with extraction rate of 70% this ratio was less than one. The percentage contribution of a-T3 and b-T3 to the total tocols content in whole meal and brown flours was within a range of 23–35% but that noted for light flours was within a lower range. The baking process caused a significant decrease in the content of tocotrienols as well as tocopherols. The level of tocotrienols in whole meal rye breads was about five, three and two times higher when compared to the bread formulated on brown flours originated from Amilo, Warko and Dańkowskie Złote. Moreover, the level of tocotrienols found in breads formulated on light flour (extraction rate of 70%) was about 2–13% of that noted in breads based on whole meal flour.
6

Allelopathic influence of common buckwheat root residues on selected weed species

88%
Szwed M., Wiczkowski W., Szawara-Nowak D., Obendorf R. L., Horbowicz M.
Acta Physiologiae Plantarum
|
2019
|
tom 41
|
nr 06
This study was conducted to determine if common buckwheat (Fagopyrum esculentum Moench) root residues (BRR) in soil are effective in limiting the growth and metabolic responses of barnyard grass (Echinochloa crus-galli (L.) P. Beauv.), wind grass (Apera spica-venti L.), cleavers (Galium aparine L.), and tiny vetch (Vicia hirsuta L.). After removal of above ground parts, BRR of 14-day-old buckwheat plants remained in soil for an additional 7 days when the weeds were seeded. After 30 days of growth, biomass of above ground parts of the weeds as well as free and bound phenolic acids and flavonoids were determined. Antioxidant capacity and peroxidase activity were measured in barnyard grass and cleavers. The biomass of 30-day-old plants of barnyard grass and cleavers grown in bare soil was approximately 5- and 3.5-fold higher, respectively, than in plants grown in the presence of BRR. BRR did not affect the biomass of wind grass and tiny vetch plants, but activate the antioxidant response, increase in peroxidase activity, and the content of phenolic compounds in weed tissues, which indicates an adaptation to the stressful environmental conditions.
7

Evaluation of vitamins B1 and B2, soluble proteins and phytic acid in buckwheat enhanced wheat bread

88%
Frias J., Penas E., Szawara-Nowak D., Zielinski H., Vidal-Valverde
Polish Journal of Food and Nutrition Sciences
|
2011
|
tom 61
|
nr Suppl.1
8

Bioavailability of anthocyanins from red cabbage products

88%
Wiczkowski W., Topolska J., Szawara-Nowak D., Ornatowska A., Piskula M. K.
Polish Journal of Food and Nutrition Sciences
|
2011
|
tom 61
|
nr Suppl.1
9

The impact of short-term exposure to Pb and Cd on flavonoid composition and seedling growth of common buckwheat cultivars

76%
Horbowicz M., Debski H., Wiczkowski W., Szawara-Nowak D., Koczkodaj D., Mitrus J., Sytykiewicz H.
Polish Journal of Environmental Studies
|
2013
|
tom 22
|
nr 6
The aim of this study was to compare the tolerance of seedlings of three Polish buckwheat cultivars (Hruszowska, Kora, and Luba) for short-term exposure to Pb²⁺ and Cd²⁺. Seedlings were grown under controlled conditions in Hoagland nutrient solution, with the addition of low/high Pb²⁺ or Cd²⁺ ions (0.01 and 1.00 mM, respectively). After 3 days of treated seedling growth, the levels of total anthocyanins and content of particular flavonoids were measured. The presence of low concentrations of both Pb²⁺ and Cd²⁺ resulted in a small stimulation of the growth of seedlings of all studied cultivars, while higher doses inhibit root growth and, to a much lesser extent, that of shoots. Cadmium (Cd²⁺) ions were more harmful for growth of buckwheat seedlings than Pb²⁺ ions. More resistant to stress caused by the presence of high concentrations of Pb²⁺ and Cd²⁺ in the growth medium were seedlings of Hruszowska and Luba cultivars, compared to Kora seedlings. Cotyledons of more resistant cultivars (Hruszowska and Luba) contained much more flavonoids than cotyledons of Kora.
10

Methyl jasmonate stimulates biosynthesis of 2-phenylethylamine, phenylacetic acid and 2-phenylethanol in seedlings of common buckwheat

76%
Horbowicz M., Wiczkowski W., Sawicki T., Szawara-Nowak D., Sytykiewicz H., Mitrus J.
Acta Biochimica Polonica
|
2015
|
tom 62
|
nr 2
11

A rapid method for measurement of total antioxidant status of selected cereal grains - short report

64%
Zielinski H., Honke J., Latosz A., Troszynska A., Ciska E., Waszczuk K., Szawara-Nowak D., Kozlowska H.
Polish Journal of Food and Nutrition Sciences
|
1998
|
tom 07
|
nr 3
533-538
The purpose of this study was to examine a rapid method for measurement of total antioxidant status (TAS) from a sample of selected cereal grains. Extracts prepared from buckwheat and oat had higher TAS values than extracts from wheat and barley. TAS value of extract from rye was below detection limit. We indicate that values of TAS of selected cereal grains strongly depend on the content of phenolic compounds and soluble protein. The test employed in the study, can be applied in estimation of the Total Antioxidant Status of substances extracted from cereals with phosphate buffer pH=7.0.
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