Antioxidant activity of dietary oregano essential oil and alpha-tocopheryl acetate supplementation in long-term frozen stored turkey meat

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.     

Nitrogen and carbon mineralization of semi-arid shrubland soil exposed to long-term atmospheric nitrogen deposition

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.     

Implementing optimal sulphur abatement strategies in Europe

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.     

Nutritional and physiological responses of young growing rats to diets containing raw cowpea seed meal,protein isolate (globulins), or starch

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.     

Cadmium and other heavy metals in sea-skaters

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.     

Automated determination of alpha-tocopherol in food and feed. Part 2. Continuous flow technique

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.     

Observations of water,air and soil pollution in Israel and vicinity from the ERTS-1 imagery

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.     

Role of air pollution in forest decline in Eastern North America

Evidence for and against three general mechanisms by which air pollution stress may cause or contribute to forest decline in eastern North America is examined. These mechanisms are (1) soil acidification, cation nutrient depletion, and subsequent Al toxicity, (2) direct and indirect effects of gaseous pollutants on the physiology and growth of forest trees; and (3) excess nitrogen deposition and subsequent soil acidification or physiological injury. Recent studies have revealed reductions in base saturation in some sites (both polluted and pristine), but the consequences of these changes to forest health and nutrition are not resolved. Aluminum toxicity may contribute to forest decline in red spruce (Picearubens L.) in high-elevation sites, but the data are contradictory. In forested landscapes in which regional decline (reduced tree growth and/or dieback) is reported, O₃ is the only gaseous pollutant documented as a contributing factor in the eastern North America. Whereas this secondary pollutant exhibits a regional distribution and occurs at potentially phytotoxic levels, a linkage between O₃ and forest decline is substantive only for loblolly pine (Pinustaeda Sarg.) in the southeast. Studies in high elevations do not support the hypothesis that O₃ or hydrogen peroxide directly affects the growth of red spruce or fraser fir (Abiesfraseri Poir.).However, preliminary data link chronic-level O₃ exposure with indirect effects, principally changes in drought tolerance in low-elevations (e.g., P. taeda) nd winter hardiness in high elevations (e.g., P. rubens).The emerging data on the role of air pollution as an environmental stress indicate that indirect effects (i.e., responses in which pollution alters the plant's ability to compete for limited resources or withstand other environmental stresses) are more important than direct effects (e.g., foliar necrotic lesions). Nitrogen saturation has been offered as an hypothesis for P. rubens decline, but no experimental data exist supporting this hypothesis.     

Extrusion conditions affect chemical composition and in vitro digestion of select food ingredients

An experiment was conducted to determine the effects of extrusion conditions on chemical composition and in vitro hydrolytic and fermentative digestion of barley grits, cornmeal, oat bran, soybean flour, soybean hulls, and wheat bran. Extrusion conditions altered crude protein, fiber, and starch concentrations of ingredients. Organic matter disappearance (OMD) increased for extruded versus unprocessed samples of barley grits, cornmeal, and soybean flour that had been hydrolytically digested. After 8 h of fermentative digestion, OMD decreased as extrusion conditions intensified for barley grits and cornmeal but increased for oat bran, soybean hulls, and wheat bran. Total short-chain fatty acid production decreased as extrusion conditions intensified for barley grits, soybean hulls, and soybean flour. These data suggest that the effects of extrusion conditions on ingredient composition and digestion are influenced by the unique chemical characteristics of individual substrates.     

Permethrin and its two metabolite residues in seven agricultural crops

Metabolite residues of permethrin are not reported in the literature for most agricultural crops. This paper reports residues of permethrin and its 2 metabolites (dichlorovinyl acid and metaphenoxybenzyl alcohol) in 7 different agricultural crops (Chinese cabbage, spinach, asparagus, raspberries, green peas, turnip roots, and turnip greens). Permethrin residues declined approximately 85% within 7 days after treatment in all crops. In most cases, the acid metabolite residues peaked at 3 days, and declined after that. Translocation of residues into turnip roots was very slight; the average was less than 0.05 ppm for permethrin and alcohol metabolite residues and none was detected for the acid metabolite residue. Permethrin residues in the turnip greens averaged approximately 2 ppm for the 0.112 kg ai/ha treatment, and 6 ppm for the 0.224 kg ai/ha treatment.