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The aim of this study was to compare vitamin C and β-carotene contents in cruciferous vegetables (Brassica oleracea) grown under diversified ecological conditions for three consecutive years. The hypothesis to be verified was that statistically, vitamin C and β-carotene contents in cruciferous vegetables from the closest areas around a steelworks, organic farms, and randomly purchased in retail differed significantly, independent of the climate and agro-technical conditions. The study was done on three species of cruciferous vegetables: ‘Stone head’ white cabbage, ‘Langedijker’ red cabbage, and ‘Dolores F1’ Brussels sprouts. All these species of cruciferous vegetables were characterized by significantly higher vitamin C and β-carotene contents (Brussels sprouts) when grown on organic farms vis-à-vis vegetables grown around a steelworks or available in retail in Kraków, which may be evidence of efficient organic growing technology, and may indicate another way to improve the quality of food.
Background. The aim of this study was to compare total polyphenol contents and antioxidant activity of three species of cruciferous vegetables grown under diversified ecological conditions for three consecutive years. Material and methods. Methanol extracts were prepared to be used to determine (spectrometrically) the content of total phenolics, using the Folin-Ciocalteau reagent and antioxidant activity by identifying the sample’s ability to extinguish an ABTS,+ free radical. Results. Ali these species of cruciferous vegetables contained similar total polyphenols amounts regardless of its origin. Only red cabbage from organic farms was characterized by significantly higher antioxidant activity compared to vegetables purchased from local retailers in Cracow and similar or those cultivated near the steelworks. In white cabbage from farms located in a former steelworks protection zone a higher antioxidant activity was found than in organically grown vegetables and similar to that in vegetables available in retail. Brussels sprouts was characterised by a similar antioxidant activity regardless of its origin. Conclusions. On the basis of the present study, it cannot be concluded that organically grown cruciferous vegetables generally have higher contents of health-promoting secondary metabolites in comparison with the conventionally cultivated ones.
Brassica vegetables, including white cabbage, both fresh and sour (Brassica oleracea L. var. capitata L.), contain a lot of valuable metabolites which are effective in chemoprevention of cancer as documented by numerous studies. This work investigates the effect of different packaging types; low density polyethylene (PE-LD) and metalized polyethylene terephthalate (PET met/PE) with polyethylene bags on selected quality parameters in chill-stored white sauerkraut. Sauerkraut was subjected to refrigerated storage for 4 months. Every month, stored sauerkraut was analyzed in terms of vitamin C, total phenolic compounds content and antioxidant activity. Statistical analysis demonstrated that the type of packaging had a significant influence on the antioxidant activity of chilled stored sauerkraut.
Brassica vegetables, including caulifl ower, are characterized by a high number of valuable metabolites, which act effectively in the cancer chemoprevention, as was already revealed by several studies. This work investigates the effect of the type of container: low density polyethylene (PE-LD) packages and oriented polystyrene (OPS) packages on selected quality parameters in frozen caulifl ower. The vegetable was subjected to blanching, freezing and 3 months of storage. At every stage of the experiment, the material was examined in terms of: dry matter, vitamin C, total polyphenols content, and antioxidant activity. Statistical analysis proved that the type of container had no considerable effect on the levels of the aforementioned constituents and antioxidant activity in the freeze-stored vegetables.
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The products of plant origin are a rich source of biologically active substances, both nutritive and referred as anti-nutritive. A large group of these compounds are substances with antioxidant activity that fights against free radicals. In the family of Brassicaceae vegetables, Brassica, is the largest and most widely consumed a group of plants in Europe and all over the world. They are characterized by different levels of nutrients. However because of their large and frequent consumption, they may become a significant source of nutrients and bioactive compounds in the daily diet. The beneficial effects of Brassica vegetables on human health have been somewhat linked to phytochemicals. They prevent oxidative stress, induce detoxification enzymes, stimulate immune system, decrease the risk of cancers, inhibit malignant transformation and carcinogenic mutations, as well as, reduce proliferation of cancer cells. Brassica vegetables contain a lot of valuable metabolites, which are effective in chemoprevention of cancer, what has been already documented by numerous studies. Due to the presence of vitamins C and E, carotenoids and antioxidant enzymes such as catalase, superoxide dismutase (SOD) and peroxidase, these vegetables are considerable source of antioxidants, and due to the presence of polyphenols and the sulfur-organic compounds exert also antimutagenic action. Moreover, these vegetables are also rich in glucosinolates, which are unstable compounds and undergo degradation into biologically active indoles and isothiocyanates under the influence of enzyme presented in plant tissues- myrosynase. These substances through the induction of enzymatic systems I and II phase of xenobiotics metabolism may affect the elimination or neutralization of carcinogenic and mutagenic factors, and consequently inhibit DNA methylation and cancer development. Despite many healthy benefits upon eating of cruciferous vegetables, it has been also seen a negative impact of their certain ingredients on the human body.
Celem pracy było określenie wpływu dodatku zakwasu do ciasta pszennego i sposobu wypieku (tradycyjnego oraz odroczonego, z zastosowaniem procesu zamrażania i zamrażalniczego przechowywania) na zawartość w bułkach skrobi i polifenoli ogółem oraz wartość indeksu glikemicznego, oznaczonego metodą in vitro. Badano cztery warianty bułek pszennych: 1) wypieczone w sposób tradycyjny (TRAD), jako próba kontrolna, 2) z 3-procentowym dodatkiem zakwasu (TRAD+Z) wypieczone w sposób tradycyjny, 3) częściowo podpiekane i zamrożone, a następnie dopiekane (ODR), 4) z 3-procentowym dodatkiem zakwasu (ODR+Z) częściowo podpiekane i zamrożone, a następnie dopiekane. Zastosowanie technologii odroczonego wypieku wpłynęło na zmniejszenie zawartości suchej masy w badanych bułkach (p<0,05) z ok. 74 do ok. 65 - 66 %. Dodatek zakwasu oraz zastosowanie mrożenia i zamrażalniczego przechowywania przyczyniły się do istotnego (p<0,05) zwiększenia zawartości skrobi wolno trawionej (SDS) w bułkach pochodzących z odroczonego wypieku (ODR – 12,6 % s.m, ODR+Z – 16,10 % s.m) w stosunku do bułek wypiekanych tradycyjnie (TRAD – 7,4 % s.m., TRAD+Z – 7,5 % s.m. Zawartość skrobi szybko trawionej (RDS) była istotnie mniejsza (p < 0,05) w bułkach z dodatkiem zakwasu: ODR+Z – 27,4 % s.m. i TRAD+Z – 27,3 % s.m. w porównaniu z bułkami kontrolnymi TRAD – 30,8 % s.m., jak również z bułkami wypiekanymi w sposób odroczony, ale bez dodatku zakwasu ODR – 29,1 % s.m. Zastosowanie procesu mrożenia i zamrażalniczego przechowywania przyczyniły się do istotnego (p<0,05) zwiększenia zawartości polifenoli ogółem w badanych bułkach [mg kwasu galusowego w 100 g s.m.]: ODR+Z – 105,2 i ODR – 105,7 vs. TRAD – 60,2 i TRAD+Z – 57,7. Natomiast dodatek zakwasu nie wpłynął na wzrost zawartości polifenoli ogółem w badanych bulkach (p < 0,05). Dodatek zakwasu oraz zastosowanie mrożenia i zamrażalniczego przechowywania spowodowały istotne (p<0,05) zmniejszenie wartości indeksu glikemicznego, oznaczonego metodą in vitro, a wyrażonego wskaźnikiem trawienia skrobi (SDI). Największą wartością SDI charakteryzowały się bułki TRAD – 76,4 % s.m., a najmniejszą – bułki ODR+Z – 53,2 % s.m. Dodatek zakwasu w proszku do ciasta z mąki pszennej jasnej i technologia odroczonego wypieku z zastosowaniem zamrażalniczego przechowywania półproduktu umożliwiają otrzymanie bułek pszennych o niskim indeksie glikemicznym oraz o zwiększonej zawartości polifenoli.
The aim of this study was to assess the influence of different soaking and cooking methods on contents of selected nutrients in legume seeds. The experimental material were dried kidney-bean seeds and soya bean seeds originating from the collection of Krakow’s Plants and Seeds Horticulture POLAN LTD. Technological treatment of seeds was performed in two stages: (1) cold and hot soaking, (2) cooking with three different devices: electric and induction stoves and microwave apparatus. The experimental material was determined for contents of: dry matter, protein, fat, ash, carbohydrates and selected mineral compounds (Ca, Mg, Na, K). The soaking and cooking of the seeds were observed to affect an increase in contents of protein, fat, ash, calcium and sodium in dry matter as well as a decrease in contents of digestible carbohydrates, potassium and magnesium. A more favorable method of soaking kidney bean seeds turned out to be hot soaking, which caused smaller losses of nutrients and shortened significantly the whole process. Cooking soya bean and kidney bean seeds with electric and induction stoves facilitated better protein preservation in comparison to the thermal treatment performed in a combined microwave oven.
Background. Dry legumes seeds are food of high nutrient density. Besides the biologically precious protein they contain essential unsaturated fatty acids, vitamins of group B, dietary fiber and antioxidants. The aim of the research was to assess the influence of different soaking and cooking methods on dietary fiber and phenolic compounds content, as well as antioxidative activity of selected legumes’ seeds. Material and methods. The experimental material was dry kidney bean originating from collection of Krakow’s Plants and Seeds Horticulture POLAN LTD, and soya bean seeds bought at the market store. The technological treatment of seeds was performed in two stages: 1) soaking in cold and hot water, 2) cooking with three different kinds of equipment - electrical stove, induction stove and microwave oven. In the above described ways prepared material was examined for the dietary fiber and phenolic compounds content, as well as antioxidative activity. Results. The highest amount of dietary fiber was found in soya bean seeds cooked on an induction stove (27.4 g-100 g'1 d.m.) and electric stove (27.3 g-100 g'1 d.m.) after previous soaking in hot water. The dry soya bean and kidney bean seeds were characterised by a high content of phenolic compounds 163.2 mg GAE-100 g.1 d.m. and 173.1 mg GAE-100 g.1 d.m. respectively. The dry matter of cooked (on induction and electric stove) kidney bean and soya seeds was characterised by a higher phenolic compounds level (232.7- -311.6 mg GAE-100 g"1 and 224.4-315.6 respectively) than raw material. Antioxidative activity of untreated seeds of kidney bean and soya bean was 4.5 and 4.1 pmol Tx g.1 d.m. respectively. The high ability of free radicals scavenging was observed in kidney bean i.e. 8.7 pmol Tx-g.1 d.m. after traditional soaking and 9.5 pmol Tx-g_1 d.m. after “hot” soaking. Conclusions. Soaking and cooking of seeds (despite the species) influenced growth of phenolic compounds content in dry matter. More advantageous way of soaking of kidney bean seeds was “hot” soaking. That way of treatment caused, first of all, shortening of the whole heat treatment process. Cooking of soya and kidney bean seeds with electric and induction stoves favoured keeping of dietary fiber, phenolic compounds and antioxidative activity of seeds in comparison to thermal treatment in combined microwave oven.
Celami badań były oznaczenie frakcji żywieniowych skrobi oraz ocena wartości wskaźnika trawienia skrobi zawartej w ziemniakach odmiany Lord, surowych i poddanych powszechnie stosowanym metodom obróbki kulinarnej. Materiał badawczy stanowiły ziemniaki, które poddano gotowaniu, odgrzewaniu w mikrofalówce oraz smażeniu. Zawartość skrobi całkowitej nie uległa istotnym zmianom na skutek zastosowanych technik kulinarnych (p > 0,05) i wynosiła średnio 11,8 g·100 g⁻¹. Wykazano natomiast, że smażone ziemniaki charakteryzowały się większą zawartością skrobi opornej (1,2 g·100 g⁻¹) i powoli trawionej (1,0 g·100 g⁻¹), w porównaniu do ziemniaków przygotowanych innymi technikami kulinarnymi. Odgrzewanie na drugi dzień ugotowanych ziemniaków w mikrofalówce również w istotny sposób wpływało na tworzenie się skrobi opornej (1,1 g·100 g⁻¹). Wykazano jednak, że zarówno gotowane, smażone, jak i odgrzewane ziemniaki zawierały dużą ilość skrobi szybko trawionej i tym samym miały wysokie wartości wskaźnika trawienia skrobi (81–92%).
Relatively little is known on the interaction between iodine and selenium in plants. It may become a drawback in developing agrotechnical rules of plant biofortification with these elements. The aim of the study was to determine the influence of soil fertilization with various forms of iodine (I- and IO₃ - ) and selenium (SeO₃ ²- and SeO₄ ²-) on yield, biofortification efficiency and selected chemical properties of lettuce plants. The study (conducted in 2012–2014) included soil fertilization of lettuce cv. ‘Valeska’ in the following combinations: control (without iodine and selenium fertilization), KI, KIO₃, Na₂SeO₄, Na₂SeO₃, KI + Na₂SeO₄, KIO₃ + Na₂SeO₄, KI + Na₂SeO₃, KIO₃ + Na₂SeO₃. Iodine and selenium were applied twice: before sowing and as a top-dressing in a total dose of 5 kg I·ha- ¹ and 1 kg Se·ha-¹. Only the application of Na₂SeO4 (individually or together with iodine) exhibited strong toxic effect on plants which was accompanied by the highest accumulation of Se, selenomethionine (SeMet) and selenocysteine (SeCys) in lettuce. The accumulation of I and Se in lettuce was respectively higher after fertilization KI than KIO3 and Na₂SeO₄ than Na₂SeO₃. Simultaneous application of iodine and selenium decreased the level of Se, SeMet and SeCys in lettuce − particularly in the combination with KIO₃ + Na₂SeO₃. Simultaneous application of KI with both forms of seleniumdecreased iodine content in lettuce as related to the treatment with KI alone. In the case of lettuce from the combinations with KIO₃, KIO₃ + Na₂SeO₄ i KIO₃ + Na₂SeO₃, comparable results of iodine concentration were obtained.
Iodine and selenium together fulfill important functional roles in organisms of humans and animals. Conducting simultaneous biofortification (enrichment) of plants with these elements is justified as combined endemic deficiency of I and Se (hiddenhun-ger) is often encountered. Relatively little is known about the interaction between I and Se in plants, not only with respect to their accumulative efficiency, but also its influence on mineral nutrition or biological quality of crop. The study (conducted in 2012–2014) in-cluded soil fertilization of lettuce cv. ‘Valeska’ with I and Se in the following combina-tions: control, KI, KIO3, Na2SeO4, Na2SeO3, KI + Na2SeO4, KIO3 + Na2SeO4, KI + Na2SeO3, KIO3 + Na2SeO3. Iodine and selenium were applied twice: before sowing and as a top-dressing (each of 2.5 kg I·ha-1 + 0.5 kg Se·ha-1) –a total dose of 5 kg I·ha-1and 1 kg Se·ha-1was used. Diversified weather conditions significantly modified the impact fertilization with I and Se had on tested aspects of nitrogen metabolism and biological quality of lettuce –except for the lettuce heads mass and the sucrose content. Based on the results concerning average lettuce weight as well as the level of sugars, phenolic com-pounds, phenylpropanoids, flavonols and antioxidizing activity it was concluded that the application of Na2SeO4alone or together with iodine acted as a stress factor for cultivated plants.
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