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1

Analysis of PPB amounts of aldehydes in water by solid phase extraction

100%
Nawrocki J., Kalkowska I., Dabrowska A.
Polish Journal of Environmental Studies
|
1996
|
tom 05
|
nr 3
Ozonation is commonly used in drinking water treatment technology. Ozone reacts with natural organic substances present in water to produce a number of by-products. Aldehydes are the important class of ozonation by-products due to their health effects. The determination of aldehydes in water by conventional analytical techniques is difficult because they are polar, unstable and exist at low concentration. A modern method to determine aldehydes in drinking water applies derivatization with 0-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine (PFBOA) and liquid-liquid extraction (LLE). The objective of this study was to improve the method by applying solid phase derivatization and extraction. C18 Baker SPE sorbents were used for simultaneous derivatization and enrichment of aldehydes. Detection limits with GC/ECD technique were in the low ppb range.
2

Application of Zr-Mg-Y-O catalyst for ketonization of ester and alcohol type industrial wastes

86%
Klimkiewicz R., Grabowska H., Teterycz H.
Polish Journal of Environmental Studies
|
2003
|
tom 12
|
nr 1
Aldehydes and their derivatives – primary alcohols and esters undergo ketonization in the gas phase in the range of 350-450 oC over multicomponental oxide catalyst – Zr-Mg-Y-O. This method is appropriate for processing mixtures of components. An experimental study was performed on ketonization of methyl esters fractions of waste fats and residuary alcohol fractions originating from industrial installations. In both cases mainly ketone fractions were obtained. During transformation of methyl esters and alcohols total yields of ketones amounted to over 60% and about 75%, respectively. Also, other catalytic systems (i.e. Fe-Si-Cr-K-O and Sn-Ce-Rh-O) can be used for ketonization of both raw materials.
3

Primary alcohols, aldehydes and ester transformations into ketones over oxide catalysts

72%
Klimkiewicz R.
Polish Journal of Environmental Studies
|
2008
|
tom 17
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nr 5
727-731
This paper presents the suitability of the unpopular bimolecular reaction of primary alcohol condensation to ketones as the management method for waste or excessive materials containing primary alcohols, aldehydes and esters. This method simultaneously allows winning non symmetric or long-chain ketones.
4
Content available remote

Inhibition of salivary amylase activity by cigarette smoke aldehydes

72%
Weiner D., Levy Y., Khankin E. V., Reznick A. Z.
Journal of Physiology and Pharmacology. Supplement
|
2008
|
tom 59
|
nr 6
727-737
5

Monitoring of sugar substrates utilization by D-2 and As-4 yeasts and kinetics of by-products formation during alcoholic fermentation of rye and corn mashes

72%
Klosowski G., Czuprynski B., Sieliwanowicz B., Kotarska K., Wolska M.
Polish Journal of Food and Nutrition Sciences
|
2001
|
tom 10
|
nr 2
On the basis of the HPLC analysis, the process and products of enzymatic degradation of rye and corn starch by amolytic enzymes in mashing by the PLS technology (pressureless liberation of starch) have been presented. The results of monitoring of the sugar substrates utilization by Saccharomyces cerevisiae: D-2 and As-4 yeasts during three-day fermentation have been presented. An effective and quick method (by capilary GC) allowing to investigate the kinetics of by-product formation, Le. higher alcohols, aldehydes, methanol, during alcoholic fermentation has been described. It was found that the synthesis of fusel alcohols proceeded according to the Ehrlich's model and was dependent on the glucose accessibility in the base. The most intense formation of the carbonyl compounds (mainly acetic aldehyde) was observed in the phase of preliminary fermentation.
6

The estimation of antibiotic activity of volatile oil substances

72%
Holderna-Kedzia E., Kedzia B.
Herba Polonica
|
2007
|
tom 53
|
nr 2
7

The effect of aldehydic products of lipid peroxidation on structure of erythrocyte membranes

72%
Zavodnik I., Lapshina E., Bryszewska M.
Current Topics in Biophysics
|
1994
|
tom 18
|
nr 2
8

Salivary aldehyde dehydrogenase - temporal and population variability, correlations with drinking and smoking habits and activity towards aldehydes contained in food

58%
Giebultowicz J., Dziadek M., Wroczynski P., Woznicka K., Wojno B., Pietrzak M., Wierzchowski J.
Acta Biochimica Polonica
|
2010
|
tom 57
|
nr 3
 Fluorimetric method based on oxidation of the fluorogenic 6-methoxy-2-naphthaldehyde was applied to evaluate temporal and population variability of the specific activity of salivary aldehyde dehydrogenase (ALDH) and the degree of its inactivation in healthy human population. Analyzed was also its dependence on drinking and smoking habits, coffee consumption, and its sensitivity to N-acetylcysteine. Both the specific activity of salivary ALDH and the degree of its inactivation were highly variable during the day, with the highest activities recorded in the morning hours. The activities were also highly variable both intra- and interpersonally, and negatively correlated with age, and this correlation was stronger for the subgroup of volunteers declaring abstinence from alcohol and tobacco. Moderately positive correlations of salivary ALDH specific activity with alcohol consumption and tobacco smoking were also recorded (rs ~0.27; p = 0.004 and rs = 0.30; p = 0.001, respectively). Moderate coffee consumption correlated positively with the inactivation of salivary ALDH, particularly in the subgroup of non-drinking and non-smoking volunteers. It was found that mechanical stimulation of the saliva flow increases the specific activity of salivary ALDH. The specific activity of the salivary ALDH was strongly and positively correlated with that of superoxide dismutase, and somewhat less with salivary peroxidase. The antioxidant-containing drug N-acetylcysteine increased activity of salivary ALDH presumably by preventing its inactivation in the oral cavity. Some food-related aldehydes, mainly cinnamic aldehyde and anisaldehyde, were excellent substrates of the salivary ALDH3A1 enzyme, while alkenals, particularly those with short chain, were characterized by lower affinity towards this enzyme but high catalytic constants. The protective role of salivary ALDH against aldehydes in food and those found in the cigarette smoke is discussed, as well as its participation in diminishing the effects of alcohol- and smoking-related oxidative stress.
9

Energy balance for a three-way catalytic reactor

58%
Ambrozik A., Danilczyk W., Kruczynski S.
Teka Komisji Motoryzacji i Energetyki Rolnictwa
|
2006
|
tom 06
10
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Investigation of the applicability of SPME-GC-MS technique and principal component analysis in the evaluation of a volatile fraction of blue-veined cheeses

58%
Berezinska A., Bzducha A., Obiedzinski M. W.
Polish Journal of Food and Nutrition Sciences
|
2007
|
tom 57
|
nr 4[A]
7-11
An object of the research were five blue-veined cheeses purchased at local supermarkets. Additionally, a cheese being a combination of a blue-type and another rennet coagulated cheese was evaluated. Extraction of the volatile components was performed by means of SPME in the headspace mode (HS-SPME) and followed by GC/MS separation and identification of the compounds isolated. Then, PCA was applied to the data obtained. The dimensionality of the data set was reduced from 27 volatiles to only four principal components (PCs), which accounted for about 93% of the total variance and allowed the classification of the samples studied.
11

The influence of pH and Fe(II) ions on physicochemical properties of oxidised potato starch

58%
Pietrzyk S., Fortuna T., Ras L.
Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology
|
2007
|
tom 10
|
nr 4
12
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Monitorowanie oksydatywnotermicznych przemian tluszczow metoda spektrofotometryczna

51%
Tynek M., Drozdowski B.
Żywność Technologia Jakość
|
1998
|
tom 05
|
nr 4
27-38
13

Penicillium expansum growth and production of patulin in the presence of benzoic acid and its derivatives

51%
Florianowicz T.
Acta Microbiologica Polonica
|
1998
|
tom 47
|
nr 1
14
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Sex propheromone of the pine tree lappet moth Dendrolimus pini and its use in attractant-based monitoring system

44%
Grodner J., Zander R.
Pestycydy
|
2010
|
nr 1-4
The study presents a new strategy of synthesis of the pine-tree lappet moth sex pheromone via hydrolysis of the (5Z,7E)-1,1-diethoxy-5,7-dodecadiene (propheromone) and their using in biological tests with pheromone traps. The field trials showed that a sticky delta traps with propheromone at dose of 2.4 mg was the most suitable for monitoring of the population of the pine tree lappet moth.
15

Wplyw heksenalu i nonenalu na wzrost i zarodnikowanie Fusarium oxysporum f. sp. tulipae

44%
Jarecka A., Saniewska A.
Progress in Plant Protection
|
2007
|
tom 47
|
nr 2
123-127
16

Wpływ aldehydów heksenalu i nonenalu na wzrost i rozwój trzech form specjalnych Fusarium oxysporum

44%
Jarecka Boncela A. J., Saniewska A.
Progress in Plant Protection
|
2010
|
tom 50
|
nr 1
The effect of heksenal and nonenal on growth and development of fhree isolates of Fusarium oxysporum Schlecht. f. sp. callistephi (Foc), f. sp. dianthi (Fod) and f. sp. narcissi (Fon) was investigated. Heksenal added PDA (Merck) at the concentration of 100 μg/cm³ limited the growth of Foc, Fod and Fon by 45%. Effectiveness of the tested product was positively correlated with the increase of its concentration, however even at a maximal concentration of heksenal (300 μg/cm³) mycelial growth of Foc, Fod and Fon was still not inhibited in full. Nonenal at the concentration of 300 μg/cm³ totally inhibited the mycelium growth of Foc, Fod and Fon. The spore germination of Foc and Fod was totally inhibited at the concentration of heksenal and nonenal of 300 μg/cm³ of the compound however, colony forming units of Fon did not develop at the concentration of 400 μg/cm³ of tested product in selective Komada’s medium.
17

Wplyw kontaktu stali oraz powlok z tworzywa PET na jakosc ziemniaczanego spirytusu surowego [1]

44%
Czuprynski B., Kotarska K., Klosowski G., Wolska M.
Przemysł Fermentacyjny i Owocowo-Warzywny
|
2003
|
tom 47
|
nr 10
24-26
W artykule przedstawiono badania nad wpływem kontaktu stali stosowanej na zbiorniki magazynowe w przemyśle fermentacyjnym i spirytusowym oraz powłok z tworzywa PET na jakość ziemniaczanego spirytusu surowego. W badanym spirytusie, w wyniku korozji stalowych płytek, stwierdzono zwiększenie zawartości aldehydów, związków karbonylowych oraz innych zanieczyszczeń. W przechowywanym spirytusie najlepsza okazała się powłoka z PET – zmiany fizykochemiczne i organoleptyczne badanego spirytusu były porównywalne ze zmianami, jakie zaszły w spirytusie przechowywanym w szklanym słoju (próbka kontrolna).
18

Wplyw kontaktu stali oraz powlok z tworzywa PET na jakosc ziemniaczanego spirytusu surowego [2]

44%
Czuprynski B., Kotarska K., Klosowski G., Wolska M.
Przemysł Fermentacyjny i Owocowo-Warzywny
|
2003
|
tom 47
|
nr 11
22-23
W artykule przedstawiono badania nad wpływem kontaktu stali stosowanej na zbiorniki magazynowe w przemyśle fermentacyjnym i spirytusowym oraz powłok z tworzywa PET na jakość ziemniaczanego spirytusu surowego. W badanym spirytusie, w wyniku korozji stalowych płytek, stwierdzono zwiększenie zawartości aldehydów, związków karbonylowych oraz innych zanieczyszczeń. W przechowywanym spirytusie najlepsza okazała się powłoka z PET – zmiany fizykochemiczne i organoleptyczne badanego spirytusu były porównywalne ze zmianami, jakie zaszły w spirytusie przechowywanym w szklanym sloju (próbka kontrolna).
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