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Z ziarniaków pszenicy otrzymano ekstrakt związków fenolowych stosując ekstrakcję 80% metanolem i niskociśnieniową chromatografię kolumnową na żelu RP-18. Związki fenolowe zawarte w tak otrzymanym ekstrakcie analizowano następnie jakościowo metodą RP-HPLC-DAD w systemie gradientowym. Otrzymany chromatogram charakteryzował się obecnością 8 głównych pików. Jeden z nich pochodził od kwasu sinapowego. Widma UV-DAD pozwalają stwierdzić, że pozostałe związki fenolowe były pochodnymi kwasu sinapowego.
Roasted sesame seeds, pumpkin seeds, sunflower seeds, soy beans, and wheat germs were obtained from Ekoprodukt company (Częstochowa, Poland). Phenolic compounds were extracted with 80% aqueous methanol. The extract of roasted sunflower seeds was characterised by a higher content of total phenolics (158 mg/g). The Total Antioxidant Capacity was the highest in the extract of roasted sunflower seeds (0.478 mmol Trolox/g) followed by the extract of roasted wheat germs (0.066 mmol Trolox/g). The extracts of roasted sunflower seeds and wheat germs were strong scavengers of DPPH radical. Their reducing power was strong as well.
Ethanolic extracts of phenolic compounds were prepared from green teas (Camellia sinensis L.), bearberry leaves (Arctostaphylos uva-ursi L.), hazelnuts (Corylus avellana), evening primrose (Oenothera biennis) and grape seeds (Vitis vinifera L.). All crude extracts were examined for their gallic acid content by HPLC. The bearberry-leaf preparation was also fractionated by a Sephadex LH-20 column chromatographic method with 95% (v/v) ethanol and acetone:water (1:1; v/v) as mobile phases: one fraction consisted of low molecular-weight phenolics and the other of tannins. To all samples tannase was applied in an effort to liberate gallic acid from the phenolic esters and hydrolysable tannins. The content of free gallic acid in the extracts ranged from 1 to 15 mg/g with the highest quantity being found in evening primrose. The content of gallic acid liberated by tannase ranged from 5 to 309 mg/g with the highest content being found in the tannin fraction from the bearberry-leaf extract.
Primula veris L. (Primulaceae) is a well-known medicinal herb. The callus induction response of three explant types: roots, cotyledons, and hypocotyls of four-week-old cowslip seedlings were evaluated. The highest statistically different callus induction rate was 93.6% and was obtained from root explants on MS medium supplemented with 0.1 mg/l BA and 5.0 mg/l PIC. Calli also appeared on 83.3% of cotyledon explants on MS medium supplemented with 1.0 mg/l BA and 3.5 mg/l 2,4-D and on 81.0% of root explants on MS medium supplemented with 0.1 mg/l KIN and 2.0 mg/l 2,4-D. These values were not statistically different. The average time required for callus initiation was 4 to 6 weeks, however, it depended on the explants type. The most suitable condition for callus proliferation and growth was MS medium with 0.5 mg/l TDZ and 0.1 mg/l NAA, and with 1.0 mg/l BA and 2.0 mg/l or 3.5 mg/l 2,4-D. No light conditions proved to be more favourable for cowslip calli induction and growth.
Celem niniejszej pracy była charakterystyka oraz porównanie wybranych wyróżników jakościowych pasztetów sterylizowanych, wytwarzanych z różnych surowców, na przykładzie siedmiu asortymentów pochodzących z różnych zakładów mięsnych. Oceniono cztery pasztety drobiowe, dwa z mięsa zwierząt rzeźnych oraz jeden z dziczyzny (trzy partie produkcyjne każdego z wyrobów). W pasztetach oznaczano zawartość wody, białka, tłuszczu, NaCl oraz pH, lepkość pozorną i składowe barwy. Dokonywano również oceny sensorycznej. Wszystkie badane pasztety spełniały wymagania Polskich Norm dotyczące limitowanych w nich składników chemicznych (tłuszczu i NaCl). Produkty drobiowe zawierały więcej wody (69,0-71,0%) i mniej tłuszczu (9,9-17,2%) niż pasztety z mięsa dużych zwierząt rzeźnych i dziczyzny (odpowiednio: 55-62,5% i 20,5- 25%). W ocenie sensorycznej najwyższe noty za wszystkie wyróżniki otrzymał jeden z pasztetów drobiowych, natomiast najniżej pod względem smaku oceniono pasztet z dziczyzny. Zaobserwowano istotną statystycznie korelację między oceną sensoryczną smaku a zawartością tłuszczu w pasztetach (r = -0,44, p ≤ 0,05).
Two flax lines overexpressing genes encoding three essential enzymes of the flavonoid synthesis pathway: chalcone synthase (CHS), chalcone isomerase (CHI), and dihydroflavonol reductase (DFR), were generated. Phenolic compounds were extracted from the flaxseed lines and the control sample (Linola) using 80% methanol. Then the complex of phenolic compounds present in the crude extract was hydrolysed at basic conditions. The crude and hydrolysed extracts were analysed using an RP-HPLC-DAD method. The chromatograms of the crude extracts of the control sample and transgenic lines were the same. The finger print analysis of the hydrolysed extracts shows the influence of the expression of genes encoding three above mentioned enzymes on the proportion between secoisolariciresinol diglucoside (SDG) and phenolic acids derivatives forming the phenolic complex in flaxseed.
The crude phenolic extracts were obtained from red bean, adzuki bean, red lentil, green lentil, broad bean, faba bean, field bean, vetch, buckwheat, buckwheat groat, hazelnuts, walnuts, and almonds using 80% (v/v) acetone. The tannin fractions were separated from the crude extracts using Sephadex LH-20 column chromatography with ethanol and 50% (v/v) acetone. The tannin fractions were characterised by colour reaction with vanillin/HCl reagent and ability to bovine serum albumin (BSA) precipitation. The yield of extraction of phenolic compounds ranged from 3.77% (buckwheat) to 17.20% (walnuts). The content of tannin fraction in the crude extracts was differentiated and ranged from 10.5% (faba bean) to 45.5% (broad bean). The tannin fraction from buckwheat possessed the highest content of tannins determined using vanillin method (1.04 absorbance unit at 500 nm/mg) whereas the lowest content was noted for broad bean (0.066 absorbance unit at 500 nm/mg). In the model system, the highest amount of BSA was precipitated by tannin fraction of hazelnuts, whereas the lowest was noted for adzuki bean.
Phenolic compounds from rapeseed were extracted into 80% (v/v) methanol. The crude extract was then separated using size exclusion high-performance liquid chromatography (SE-HPLC) on a TSK G2000SWXL column with a mobile phase of 45% acetonitrile and 0.1% TFA (v/v). Six peaks were identified on the chromatogram: the main peak originated from sinapin. Calibration of the assay was characterised by an excellent linearity of the sinapin standard (r2=1.0). The method so described can be used for screening phenolic constituents in rapeseed or canola. It is also useful for the purification of the sinapin as a standard from the crude extract.
A lignan macromolecule (LM) was extracted from defatted flaxseeds using an ethanol-dioxan system (1:1, v/v) and purified using Amberlite column chromatography with water and methanol as mobile phases. The LM was subjected to chemical hydrolysis (base, acid, base & acid), as well as to enzymatic processing using pepsin, pancreatin, cellulase, and β-glucuronidase. The study revealed that lignan macromolecule in flaxseed was not homogenous. The chemical hydrolysis as well as enzymatic treatment using β-glucuronidase and cellulase released low molecular phenolic compounds from the lignan macromolecule. The liberation of secoisolariciresinol (SECO) and free phenolic acids (p-coumaric and ferulic acids) from flaxseed lignan macromolecule as a result of the base and acid hydrolyses was noted. The application of pepsin and pancreatin did not change the composition of the lignan macromolecule.
The study analysed the stability of polyphenols present in extracts isolated from cocoa, green tea and strawberries in Hank’s Balanced Salt Solution buffers. The extracts were incubated under conditions commonly used for intestinal absorption experiments with human epithelial cells. The polyphenols were analysed with HPLC-DAD-FLD-MS method. The concentrations of most of the polyphenols monitored changed during 2 h of incubation. The fl avan-3-ols of cocoa exhibited similar stability and all were more stable at pH 6.5 than 7.4. The concentration of procyanidin B2 at pH 7.4 decreased to the highest extent. Green tea predominant catechins: epigallocatechin gallate and epigallocatechin, were very vulnerable in HBSS both at pH 6.5 and 7.4; their specific molecular structure may be responsible for this phenomenon. The anthocyanins of a strawberry extract were more stable at pH 6.5. The considerable increase in ellagic acid concentration at pH 7.4 might be explained by possible degradation of other compounds of the extract. It is highly recommended to perform stability tests before transport experiments in a cell culture model in order to avoid misinterpretation of results.
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