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The oil bearing rose (Rosa damascena) is the most important rose species in terms of fragrances and flavourings. Due to the very short blooming period and excessive amount of flowers, considerable amount of the rose flowers wait for a long time until distillation. There are losses of essential oil yield and quality use of before waited petals. The cold storage and drying applications may be alternative method for evaluate of excessive amount of flowers. Therefore in this study it was aimed to determine the effects of storage on cold (4°C) and room condition (25°C) and convective drying with different temperatures (40, 50 and 60°C) in terms of changes in volatile compositions of oil rose flowers based on direct hexane extraction. Totally 20 volatile compounds were identified in fresh, stored and dried rose petals. The detected compounds varied according to the various storage and drying conditions. It was determined that phenylethyl alcohol, citronellol, geranyl acetate, nonadecane were predominant compounds on all treatments. In the study, storing treatments led to increase on the percentage of oxygenated monoterpenes (OM) while drying treatments led to decrease on OM. It was determined that storing and drying treatments led to increase on the percentage of benzenoid compounds (BC) and aliphatic hydrocarbons (AH).
Aroma in samples of two varieties of Agaricus bisporus, i.e. KORONA 7 and EUROMYCEL 12, was analysed in terms of contents of eight carbon atom compounds (1-octen-3-ol, 3-octanone, 3-octanol, 2-octen-1-ol). Carpophores were harvested in 4 flushes according to their cap sizes. Quantitatively the dominant compound in all samples was 1-octen-3-ol, found in the highest concentrations in the 1st flush of yielding. The analysis of variance for factorial experiments, performed for both cultivars in one cultivation cycle – 2001/2002 and for one variety – KORONA 7 in two cycles, showed the effect of mushroom variety, flush of yielding and carpophores size on contents of dry matter and aromatic volatiles. Carpophores of a smaller cap diameter were characterised by a higher dry matter content and usually also higher contents of aromatic volatiles. In contrast, the effect of flush of yielding was different: the highest content of dry matter was recorded in the 4th flush, while that of aromatic compounds in the 1st flush.
The knowledge on nematodes occurrence in Polish vineyards is poor. The surveys of the species from the rhizosphere of plants were conducted between 2013 and 2014 in 12 vineyards in the northwestern part of Poland. Recovery of the nematodes was made in two steps. First, through incubation of 50 g of the roots on sieve. Second, by centrifugation method using 200 g of soil. Nematodes obtained were killed by hot 6% formaline and then processed to glycerine. Permanent slides were determined to the species using keys. During this process there were obtained nematode species from which 12 belonged to genus of fungivorous, 4 to genus of bacteriavorous and 38 to plant parasitic species. Ten of them are known as nematode vectors of plant viruses (GYFV, CLRV, TRV, AMV, SLRV, GLRaV-1, -2, -3, GVA, GVB, GVE, GFLV, GCMV, GrSPaV, GFkV, GRSPaV). Nematode fauna of vineyards needs broadly searching, especially nematode vectors of plant viruses, which are serious enemy to the vineyards. Studies on Aphelenchoides ritzemabosi in vine plants disease complex are necessary.
Background. Profile of volatile compounds is a distinct feature of wine, which is dependent on the type of wine, grapes, fermentation and ageing processes. Profiling volatile compounds in wine using fast method provides information on major groups of compounds and can be used for classification/differentiation purposes. Solid phase microextraction (SPME) was used for the profiling of volatile compounds in liquered white wines in this study. Material and methods. Different fibers were tested for this purpose: PDMS, Carboxene/ PDMS, Carboxene/DVB/PDMS, Polyacrylate, Divinylbenzene/PDMS. Different times were compared to optimize extraction process. Profile and amount of volatile compounds extracted by SPME fiber was compared for eight liquered white wines. Results. Carboxene/DVB/PDMS showed the highest efficiency in extracting higher alcohols, esters, carbonyls and terpenes. Of tested extraction times ranging from 5 to 30 min. 20 minutes was chosen providing sufficient peak responses. Using SPME total amount of volatile compounds in eight liquered wines was compared - Riversaltes, Offley Porto and Jutrzenka having the highest amount of adsorbed volatiles. Profiles of volatiles of analysed wines revealed that dominating compounds in 6 wines were esters, followed by higher alcohols, two analysed Muscat wines had high terpene contents compared to remaining wines. Conclusion. SPME can be used for relatively fast profiling of wine volatiles, that can be used for wines classification.
The aim of the study was to investigate the changes in the essential oil constituents of coriander and caraway when treated with UHP and/or elevated temperatures in a helium atmosphere. The UHP and/or heat treatment was conducted for 30 mins at 800 MPa, the temperature range was 60-121°C. The changes in the volatile oil content did not exceed 5% in all the treatment conditions. The pressure and temperature processing altered the composition of the essential oils of spices, which was examined using the GC-MS method. The most important sensory compounds, namely linalool in coriander oil and carvone in caraway oil, were not essentially changed after the processing. The final oil composition was different in the pressurised and not pressurised samples heated at the same temperature.
Plants under attack of herbivores can emit increased amounts of volatile compounds from their leaves. Similarly, mechanically-injured plants can emit volatile chemicals that differ both quantitatively and qualitatively from undamaged plants. In this experiment, mechanical injury increased the release of the secondary metabolites linalool (3,7-dimethyl-1,6-octadien-3-ol) and linalool oxide (5-ethenyltetrahydro-2-furanmethanol) by wheat plants. The amounts released varied significantly with injury type and the period of time after injury. The time interval for the volatile collection within the photophase also influenced the amount collected for each day. The increased emission of these compounds, as a result of injury, may be explained as a defense mechanism against wounding. The role of these plant volatiles can be further investigated in the context of plant response to mechanical injury, within the broader context of all types of injury
The Baltic Sea is a semi-enclosed brackish sea with only limited water exchange with the North Sea and, thus, the North Atlantic. This salty water reservoir with water residence time of approximately 25 years is contaminated with many inorganic and organic pollutants: VOCl (Volatile Organohalogen Compounds), HC (Petroleum Hydrocarbons), OPNP (Organophosphorus and Organonitrogenous Pesticides), OCP (Organochlorine Pesticides), PAH (Polycyclic Aromatic Hydrocarbons) and heavy metals. Our paper presents monitoring results and sea environmental pollution assessment of the Southern Baltic coastal zone- the area of the Gdańsk Bay, based on the analysis of sea water samples. A set of various analytes were determined: PAH (16 analytes), VOCl (6 analytes), HC (9 analytes), OPNP (8 analytes), OCP (5 analytes), heavy metals (Zn, Cd, Pb, Cu). The results were subjected to full statistical evaluation. An assessment of sea environment contamination was made by characterization of pollution sources and the definition of intercorrelations between them. The characterization of major statistically important correlations between 45 variables was performed with the use of principal component analysis technique. From the performed PCA it arose that the factor configuration was similar for all sampling points and in all cases 5 factors explain over 60% of the data variance, and the statistically significant loading factors are higher than 0.7 (with p=0.05). Additionally, analysis of variance and time series analysis were applied to define important differences between chemical species’ concentration levels in time and in accordance with sampling points’ geographical location. As a result of time series analyses carried through with consideration to sampling points, there were no statistically important differences discovered in trends of changes from 1996 up to 1999 for any of examined groups of compounds.
Essential oils from four plants, i.e. geranium, rosa, lemon and mint were tested for their activity in vitro and in vivo against Rhizoctonia solani and Fusarium oxysporum f. sp. phaseoli, the cause of root rot and wilt of beans. In vitro, they were found to have an inhibitory effect against the mycelial growth of R. solani and F. oxysporum f. sp. phaseoli. Complete inhibition in fungal growth was observed at a concentration of 4% of each essential oil and Topsin M at 400 ppm as well. In greenhouse the four essential oils were tested as seed coating and/or foliar spray. Results of seed coating at a concentration of 1% clearly demonstrate a good protection of emerged bean seeds against invasion of R. solani and F. oxysporum f. sp. phaseoli compared with the fungicide treatment. A similar trend was observed in a lower extent when the essential oils were applied as bean seeds coating followed by seedlings foliar spray under field conditions. Obvious yield increase as bean green pods, in all treatments, was significantly higher than in the control.
Celem pracy było określenie zdolności skorupy jaja do absorpcji lotnych związków fluoru. Materiałem badawczym były jaja kurze pochodzące od jednego szczepu kur rasy Rhode Island Red. Jaja poddano zróżnicowanej czasowo ekspozycji na działanie fluorku amonowego w komorze toksykologicznej. Stwierdzono, iż średnia zawartość fluorków w skorupie jaj koreluje z czasem trwania ich narażenia na działanie fluorku amonowego w powietrzu.
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