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Antioxidant and antiradical activities of cinnamic and benzoic acid derivatives, using different methods, were investigated. The total antioxidant effect was evaluated using method with linoleic acid-water emulsion. The ability to scavenge free radicals was checked using 2,2 -azinobis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS*) or 2,2-di- phenyl-1-picrylhydrazyl radical (DPPH*). The reducing power of the studied compounds solutions was also evaluated. It was stated, that the applied measuring method strongly influenced the obtained result, because in the system with ABTS* free radicals, the highest antioxidant activities possessed vanillic, sinapic and protocatechuic acid, whereas the most effective DPPH* radical scavengers were methyl ferulate, methyl syringate, syringaldéhyde and vanillic acid. In another method, linoleic acid peroxidation was effectively inhibited by the caffeic, sinapic and syringic acid. The highest reducing powers possessed protocatechuic acid, caffeic, sinapic and ferulic acid, higher than BHT and comparable to Trolox. Methylated derivatives of coumaric acid, caffeic acid, vanillic acid and syringic acid turned out to be weaker antioxidants and reducing agents than the free forms, except methyl ferulate, which possessed only slightly lower antioxidant activity than free ferulic acid, and in some measuring systems was a more effective antioxidant than ferulic acid.
The aim of the study was to estimate the dietary intake of benzoic acid (E 210) by elderly persons aged over 65 years in Poland and the assessment of risk for human health resulting from the intake of this food additive, expressed as percent of acceptable daily intake (ADI). Data on food consumption was collected in 2000 under the FAO project "Household Food Consumption and Anthropometric Survey". The maximum permitted level of E 210 usage was taken into consideration according to the Polish regulation. On the basis of the obtained results it was found that the average intake of benzoic acid as food additive by surveyed group does not present potential risk for human health hazard. Nevertheless the maximum content of E 210 in the diets was close to the ADI or in the group of women slightly exceeded the ADI.
The purpose of this study was to assess the efficacy of a probiotic containing Bacillus cereus var. Toyoi spores (Toyocerin®) and benzoic acid (VevoVitall®) on growth performance and diarrhoea in weaning pigs, against negative controls. The trial groups were as follows: (a) NC group (Negative Controls): No treatment (b) TOYO group: Same feed as in the controls plus Toyocerin® at a dose of 1 x 10⁹ Bacillus cereus var. Toyoi spores / kg feed, (c) BA group: Same feed as in the controls plus VevoVitall® at a dose of 5 g/kg feed (5000 ppm benzoic acid) and (d) TOYO+BA group: Same feed as in the controls plus Toyocerin® at a dose of 1 x 10⁹ Bacillus cereus var. Toyoi spores and VevoVitall® at a dose of 5 g/kg feed. In conclusion, the results of this study indicated that administration of Bacillus cereus var. Toyoi spores at 1 x 10⁹ / kg feed or benzoic acid at a dose of 5000 ppm or the combination of 1 x 10⁹ Bacillus cereus var. Toyoi spores and 5000 ppm of benzoic acid / kg feed, improved the growth performance parameters and reduced the severity of diarrhoea in weaning pigs.
Changes in phenolic acid content during the maturation of cherry laurel (Laurocerasus officinalis ‘Oxygemmis’) fruits were studied. Samples were obtained starting 40 days after flowering between May and July. In the fruits, p-coumaric, caffeic and ferulic acids (as cinnamics) and benzoic, 4-hydroxybenzoic, vanillic and 3,4-dihydroxybenzoic acids (as benzoics) were identified. The content of benzoic, 4-hydroxybenzoic, vanillic and caffeic acids started to increase from 6 to 12 WAF (weeks after flowering). The content of p-coumaric and ferulic acids, highest at 6 WAF, declined gradually until 11 WAF and increased again at 12 WAF. All phenolic acids except vanillic and ferulic acids began to decrease in the fruits harvested at 16 WAF, that is, the normal harvesting season. Although an increase in vanillic and ferulic acid content was observed in post-ripening between 13 and 16 WAF, the values were not statistically significant (P = 0.05) between stages. The highest content of phenolic acid in the cultivar was found for benzoic, caffeic and vanillic acids: 2.53, 1.05 and 0.86 mg/100g dry weight, respectively.
W pracy przedstawiono szybką metodę oznaczania zawartości kwasu benzoesowego w napojach bezalkoholowych gazowanych z zastosowaniem wysoko- sprawnej chromatografii cieczowej (HPLC).
Seven-day-old seedlings of cucumber (Cucumis sativus L.) cv. Wisconsin were treated with 0.01, 0.1 and 0.5 mM solutions of derivatives of cinnamic acid (ferulic and p-coumaric acids) and benzoic acid (p-hydroxybenzoic and vanillic acids) as stress factors. In cucumber roots phenolics (free and glucosylated), phenol β-glucosyltransferase (E.C. 2.4.1.35) activity as well as membrane permeability were examined. The most intensive glucosylation took place in the first hour of stress duration in roots treated with 0.01 mM ferulic and p-coumaric acids and with 0.01 and 0.1 mM p-hydroxybenzoic and vanillic acids. At these concentrations a high phenol β-glucosyltransferase activity was found. The deterioration of capacity for phenolic glucosylation as well as the decrease of the phenol β-glucosyltransferase was observed at the higher concentrations. It was associated with increased membrane permeability.
W pracy przedstawiono przegląd piśmiennictwa zagranicznego i krajowego dotyczącego kwasu benzoesowego i jego pochodnych w żywności. Wskazano na maksymalne dopuszczalne zawartości tych substancji jako konserwantów w produktach żywnościowych , zgodnie z obowiązującymi przepisami w Polsce i Unii Europejskiej. W pracy zaprezentowano możliwości badań nowych pochodnych kwasu benzoesowego o dotychczas nieznanych właściwościach konserwujących.
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