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41.
A. Clara Grosso Monya M. Costa Luisa Ganço Ana L. Pereira Generosa Teixeira José M.G. Lavado A. Cristina Figueiredo José G. Barroso Luis G. Pedro 《Food chemistry》2007,102(4):1083-1088
The essential oils, isolated by hydrodistillation and distillation-extraction, from the aerial parts of different populations of Pterospartum tridentatum collected during the flowering phase, at different locations in Portugal, were analysed by GC and GC–MS. All the P. tridentatum populations studied afforded a yellowish oil in a yield <0.05% (v/w). cis-Theaspirane (2–14%), trans-theaspirane (2–17%) and octen-3-ol (2–37%) were, in variable amounts, the dominant components of the oils. Cluster analysis of the essential oil compositions from the nine populations studied, confirmed a major chemical variability. 相似文献
42.
Michail I. Gladyshev Nadezhda N. Sushchik Galina A. Gubanenko Sevilia M. Demirchieva Galina S. Kalachova 《Food chemistry》2007,101(4):1694-1700
Frozen samples of common fish species, sea trout (Salmo trutta), from Norway and Siberia, herring (Clupea harengus pallasi), rock sole (Lepidopsetta bilineata) and cod (Gadus morhua maris-albi), collected from a wholesale market in Krasnoyarsk city (Siberia, Russia) were analyzed. Special attention was paid to long-chain essential polyunsaturated fatty acids: eicosapentaenoic, 20:5ω3 (EPA) and docosahexaenoic, 22:6ω3 (DHA). Heat-treatment (cooking and frying) did not in general significantly decrease the contents of EPA and DHA compared to raw fish species, except for a modest reduction in Norwegian trout during frying. Boiled trout appeared to be a more valuable fish dish for obtaining the officially recommended appropriate daily intake of EPA + DHA for humans. Herring and sole had intermediate values, while boiled cod had a comparatively low value. 相似文献
43.
Michał Krempski-Smejda Jan Stawczyk Krzysztof Śmigielski Renata Prusinowska 《Drying Technology》2015,33(13):1671-1677
A new product from a low temperature drying method that reduces the loss of highly volatile essential oils is presented. The proposed drying method consists of evaporation/sublimation of water and aromatic substances in a dryer with a closed drying agent cycle. In parallel, the evaporated compounds are continuously condensed in a heat exchanger. As a result of the drying process, high-quality dried plants and Fluidolat as liquid phase containing water and volatile organic compounds are obtained. The aim of presented investigations was to optimize the developed technology for the herb lavender. 相似文献
44.
两条不等宽的道路相对接时,如果中线是缓和曲线,特别是在内边线加宽的情况下,边线平滑连接涉及复杂的曲线解算。本文就此问题阐述解决的思路和方法。 相似文献
45.
The aim of this research was to exploit the chemical properties of natural products to control the incidence and extent of mould growth in houses. The screening of antimould activities of seven essential oil extracts showed that most of the extracts completely inhibited the growth of all three test mould at the concentration of 1% w/v on nutrient medium, whereas, different fractions of manuka oil showed varied activity. Subsequently, using both mycological and scanning electron microscopy, the testing of selected extracts on two different types of gypsum board finished with either paint or wall-paper, confirmed the antimould activity of eugenol, thymol and cinnamaldehyde against Penicillium corylophilum. This study identified certain essential oil extract as a potential mould inhibitor for panel products which is one of the most common mould habitats in the building environment. Mould growth in residential houses is a major concern and chemical fungicides commonly used to control the growth of mould are not often appropriate for indoor applications. Natural alternatives such as essential oils are desirable for this application. Knowledge gained through this research should lead to new niche panel product development to create healthier housing. 相似文献
46.
超临界CO_2萃取香料精油的研究 总被引:16,自引:0,他引:16
本文对熏衣草、百里香、野百里香和迷迭香4种香料单独或两种香料混合超临界CO2萃取和分级分离香料精油的工艺可行性,以及采用GC,GC-MC对萃取物的主要成分分析进行了初步研究。从两种香料混合物中革取所获产率等于从每种香料所获产率之平均值,混合萃取明显提高精油和树脂两种产品的分离效率,两种香料混合物的萃取物所含的主要成分与两种香料单独萃取的成分相同,但浓度有明显差别。 相似文献
48.
Pamidighantam Prabhakara Rao Allani Nagender Lingamallu Jaganmohan Rao Dubasi Govardhana Rao 《European Food Research and Technology》2007,224(6):791-795
Garlic cloves in the form of bits were dried in a cabinet tray dryer and a microwave dryer, and pulverized to obtain free
flowing powder. The volatile oil was obtained by hydro-steam distillation method. Fresh cloves and the powders resulting from
the two drying methods were used for obtaining the volatile oil, which was analyzed by GC-MS. The studies were mainly restricted
to comparing the effect of drying methods on the volatile oil composition of the powders. Although the drying time was reduced
considerably from 8 h in a cabinet dryer to 0.25 h in a microwave dryer, essential oil yield and color values were lower,
and flavor quality varied considerably. The relative concentrations of major peaks such as diallyl disulfide, diallyl tetrasulfide
increased in both the drying methods, and it was more so in microwave-dried samples. However, the concentrations of the other
two major peaks, diallyl trisulfide and allyl methyl trisulfide, decreased in both drying methods, and they were lower in
microwave-dried samples. Hunter values of L and b were lower for samples obtained by microwave drying as compared to those of cabinet-dried samples. 相似文献
49.
The essential oils of Foeniculum vulgare subsp. piperitum were subjected to detailed GC-MS analysis in order to determine possible similarities and differences in their chemical compositions, depending on growth years (2001 and 2002). In both oils, methyl chavicol (40.29 and 21.69%), limonene (17.66 and 22.24%), fenchone (16.90 and 12.98%), α-pinene (1.86 and 34%) and α-phellandrene (2.30 and 2.74%) were the main components, respectively. A total of 32 components were identified accounting for 85.01 and 67.14% of the oils of F. vulgare, respectively. The main characteristic of the oils is the high content of the limonene, fenchone and estragol. Our findings indicated that the oil of Turkish bitter fennel belonged to methyl chavicol rich type. 相似文献
50.
The fumigant toxicities of eucalyptus essential oil and 1,8-cineole, the major component of eucalyptus oil, were tested against a chlorpyrifos-methyl resistant strain and a reference strain of the sawtoothed grain beetle, Oryzaephilus surinamensis (L.). The resistant strain showed 1.9- and 2.2-fold higher tolerance against essential oil and 1,8-cineole fumigation toxicity, respectively, relative to the susceptible strain. The increased tolerance for the essential oil may be the result of cross-resistance. The resistance mechanisms in the resistant strain are discussed in relation to elevated detoxifying enzymes such as cytochrome P450 and esterases. 相似文献