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111.
Antioxidant activity of dietary oregano essential oil and alpha-tocopheryl acetate supplementation in long-term frozen stored turkey meat 总被引:2,自引:0,他引:2
Botsoglou NA Govaris A Botsoglou EN Grigoropoulou SH Papageorgiou G 《Journal of agricultural and food chemistry》2003,51(10):2930-2936
The effects of dietary oregano essential oil and alpha-tocopheryl acetate supplementation on the oxidative stability of long-term frozen stored turkey meat were investigated. Thirty 12-week-old turkeys, randomly divided into five groups, were given a basal diet or a basal diet supplemented with 200 mg of alpha-tocopheryl acetate kg(-1), or 100 or 200 mg of oregano oil kg(-1), or 100 mg of oregano oil plus 100 mg of alpha-tocopheryl acetate kg(-1) for 4 weeks prior to slaughter. Lipid oxidation in breast and thigh meat was assessed after 1, 3, 6, and 9 months of frozen storage at -20 degrees C prior to or following 7 days of refrigerated storage at 4 degrees C. Results showed that oregano oil increased the oxidative stability of breast and thigh meat during the frozen storage. Dietary oregano oil at the inclusion level of 200 mg kg(-1) feed was significantly (p < 0.05) more effective in delaying lipid oxidation compared to the level of 100 mg kg(-1), but equivalent to dietary alpha-tocopheryl acetate supplementation at 200 mg kg(-1), which in turn was inferior to dietary supplementation of 100 mg kg(-1) oregano essential oil plus 100 mg kg(-1) alpha-tocopheryl acetate that was significantly (p < 0.05) superior to all other treatments. Thigh meat was more susceptible to oxidation than breast meat, although the former contained alpha-tocopherol at markedly higher levels. Mean alpha-tocopherol levels in breast and thigh meat from all treatments decreased during the frozen storage, the decrease being sharper between 1 and 3 months of frozen storage for breast and between 3 and 6 months for thigh meat. Oregano oil supplementation increased (p < 0.05) the retention of alpha-tocopherol in meat, the increase being positively correlated with the supplementation level. However, the retention of alpha-tocopherol in meat could only partly elucidate the antioxidant activity exhibited by dietary oregano oil supplementation. 相似文献
112.
Anthropogenic N-deposition represents a significant input of N into semi-arid chaparral and coastal sage scrub (CSS) shrublands
of southern California. High levels of atmospheric N deposition have the potential to increase soil C and N mineralization,
and we hypothesize that semi-arid shrubland soil exposed to long-term (decades) high N deposition will have significantly
higher C and N mineralization potentials. This hypothesis was tested in a laboratory incubation where the inorganic N (NH4+NO3) and CO2 production of soils maintained at a constant temperature of 25°C and a soil moisture of 0.25 g H2O/g (65% water-filled pore space) were sampled sequentially over a 50-week period. The temporal trend in cumulative C and
N mineralization was well described by a first- and zero-order model, respectively. Long-term atmospheric N deposition significantly
increased potential N mineralization but not C mineralization, and both the rate and total N mineralization were significantly
positively correlated with the surface (0–10 cm) soil δ
15N natural abundance and negatively correlated with the surface soil C:N ratio. While the incubation techniques used here do
not provide realistic estimates of in situ C or N mineralization, these assays indicate that atmospheric N deposition has
significantly altered ecosystem N storage and cycling. 相似文献
113.
Silva RD Bueno AL Gallon CW Gomes LF Kaiser S Pavei C Ortega GG Kucharski LC Jahn MP 《Fitoterapia》2011,82(6):818-826
This study analyzed the plasma lipid profile, glucose levels and fat deposits in male rats treated with aqueous extract of gross yerba mate, commercial yerba mate or water. Yerba mate treatment did not change body weight gain and lipid profile. The consumption of gross yerba mate significantly increased blood glucose (6.6 mmol/L) as compared to the water (4.8 mmol/L) and commercial group (5.2 mmol/L) and decreased epididymal and intra-abdominal deposits (10.1 mg/g and 23.7 mg/g of weight) as compared to the water (15.4 mg/g and 36.9 mg/g of weight) and commercial group (12.5 mg/g and 28 mg/g of weight). The results suggest that gross yerba mate reduces fat more efficiently but produces a greater increase in blood glucose when compared to commercial yerba mate and water groups. 相似文献
114.
Michaelakis A Mihou AP Couladouros EA Zounos AK Koliopoulos G 《Journal of agricultural and food chemistry》2005,53(13):5225-5229
The oviposition pheromone of Culex quinquefasciatus was synthesized in a racemic form in a simple (five steps), efficient, high yielding (45% total yield), and low cost way (use of relatively low cost reagents). Our synthetic racemic pheromone (SRP) was tested in the laboratory for its bioactivity on Culex pipiens biotype molestus, which is a member of the species complex that Culex quinquefasciatusbelongs. In the testing conditions, bioactivity at the doses of 0.01, 0.1, 1, and 10 microg per cage was found with the best bioactivity achieved at 1 mug per cage. The effectiveness of our SRP offers a capable tool for improving mosquito oviposition traps for surveillance or even control programs. 相似文献
115.
George E. Halkos 《Water, air, and soil pollution》1996,87(1-4):329-344
Acid rain causes greater environmental damage than would occur if countries act cooperatively. Based on new estimates of sulphur abatement cost functions and taking into consideration the political changes in Europe due to the dissaggregation of the USSR and the unification of Germany, this paper reviews and compares a number of alternative available economic instruments which, if adopted, may encourage implementation of sulphur abatement strategies. 相似文献
116.
Olivera L Canul RR Pereira-Pacheco F Cockburn J Soldani F McKenzie NH Duncan M Olvera-Novoa MA Grant G 《Journal of agricultural and food chemistry》2003,51(1):319-325
The nutritional and physiological effects of raw cowpea (Vigna unguiculata (L) Walp.) seed meal, protein isolate (globulins), or starch on the metabolism of young growing rats have been evaluated in 14-day trials. Wet and dry weight gain, feed conversion efficiency, and lipid and protein accretion were significantly reduced as a result of inclusion of seed meal, globulins, or starch in the diet, with growth retardation being most marked with the seed meal. The proportional weights of the small intestine and pancreas were increased by meal diets, and serum cholesterol levels were slightly reduced. The globulins and raw starch also increased relative small intestine weights but had no effect on the pancreas or serum constituents. The effects of cowpeas on rats appeared to be due primarily to the combined actions of globulins, resistant starches, protease inhibitors, and possibly fiber and non-starch polysaccharides on intestinal and systemic metabolism. 相似文献
117.
Exceptionally high concentrations of Cd (100 to 200 ppm dry weight) were found in samples of Halobates collected off Baja California. In contrast, no detectable Cd was found in Rheumatobates collected from mangrove lagoons in the Gulf of California. Concentrations of five other heavy metals in the two marine insects are also presented. 相似文献
118.
C F Bourgeois P R George L A Cronenberger 《Journal of the Association of Official Analytical Chemists》1984,67(3):631-634
The proposed determination of alpha-tocopherol is a continuous flow method with fluorometric detection. The only cleanup necessary is the usual saponification. A solution of the unsaponifiable matter in isooctane is automatically assayed. Isooctane is the carrier solvent and extractions are inserted between steps. These steps are selective reactions which render the method very specific. The natural homologs of alpha-tocopherol (alpha-T) do not interfere in the determination. A procedure for blank assays allows selective inhibition of alpha-T conversions and measurement of interfering fluorescence. The method is highly sensitive, which allows the determination of alpha-T in very dilute solutions. This in turn suppresses matrix effects and renders the results reliable. The time interval between 2 peaks is 6 min, washing included, and it is possible to carry out 50 determinations per day (sample preparation not included). The system is robust and maintenance is easy. Parallel determinations of foods and feeds have been carried out with a conventional thin layer chromatographic method. 相似文献
119.
Apple replant disease (ARD) is a disease complex that reduces survival, growth and yield of replanted trees, and is often encountered in establishing new orchards on old sites. Methyl bromide (MB) has been the fumigant used most widely to control ARD, but alternatives to MB and cultural methods of control are needed. In this experiment, we evaluated the response of soil microbial communities and tree growth and yield to three pre-plant soil treatments (compost amendment, soil treatment with a broad-spectrum fumigant, and untreated controls), and use of five clonal rootstock genotypes (M.7, M.26, CG.6210, G.30 and G.16), in an apple replant site in Ithaca, New York. Polymerase chain reaction (PCR)—denaturing gradient gel electrophoresis (DGGE) analysis was used to assess changes in the community composition of bacteria and fungi in the bulk soil 8, 10, 18 and 22 months after trees were replanted. PCR-DGGE was also used to compare the community composition of bacteria, fungi and pseudomonads in untreated rhizosphere soil of the five rootstock genotypes 31 months after planting. Tree caliper and extension growth were measured annually in November from 2002 to 2004. Apple yield data were recorded in 2004, the first fruiting year after planting. Trees on CG.6210 rootstocks had the most growth and highest yield, while trees on M.26 rootstocks had the least growth and lowest yield. Tree growth and yield were not affected by pre-plant soil treatment except for lateral extension growth, which was longer in trees growing in compost-treated soil in 2003 as compared to those in the fumigation treatment. Bulk soil bacterial PCR-DGGE fingerprints differed strongly among the different soil treatments 1 year after their application, with the fingerprints derived from each pre-plant soil treatment clustering separately in a hierarchical cluster analysis. However, the differences in bacterial communities between the soil treatments diminished during the second year after planting. Soil fungal communities converged more rapidly than bacterial communities, with no discernable pattern related to pre-plant soil treatments 10 months after replanting. Changes in bulk soil bacterial and fungal communities in response to soil treatments had no obvious correlation with tree performance. On the other hand, rootstock genotypes modified their rhizosphere environments which differed significantly in their bacterial, pseudomonad, fungal and oomycete communities. Cluster analysis of PCR-DGGE fingerprints of fungal and pseudomonad rhizosphere community DNA revealed two distinct clusters. For both analyses, soil sampled from the rhizosphere of the two higher yielding rootstock genotypes clustered together, while the lower yielding rootstock genotypes also clustered together. These results suggest that the fungal and pseudomonad communities that have developed in the rhizosphere of the different rootstock genotypes may be one factor influencing tree growth and yield at this apple replant site. 相似文献
120.
Joseph Otterman Avihu Ginzburg George Ohring Yuri Mekler 《Water, air, and soil pollution》1974,3(1):53-61
Israel is a participant in the Earth Resources Technology Satellite Program (ERTS). The imagery of Israel and vicinity taken by the Multi Spectral Scanner of the ERTS-1 Satellite has been the subject of analysis in a multidisciplinary research program. The objectives of the program are mapping of agricultural crops, mainly wheat and orange groves, mapping of natural vegetation, and studies for Israeli hydrology, arid regions research, geology, and oceanography. Cases of water, air, and soil pollution have been observed in the imagery on several dates, and are reported in this paper. These are: oil slicks in the Gulf of Suez and possibly near Haifa; smoke plumes, extending over some 100 km in a nearly straight line along the Gulf of Suez, and soil pollution caused by copper mine effluents in the Arava Valley in Israel. The images of these cases of pollution are presented and ‘space signatures’, i.e., the radiometric spectral characteristics of these cases of pollution as seen from space are also given. 相似文献