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91.
Metal Enrichment in Zlatna, a Romanian Copper Smelting Town 总被引:1,自引:0,他引:1
Joanna M. Pope Margaret E. Farago Iain Thornton Emil Cordos 《Water, air, and soil pollution》2005,162(1-4):1-18
A preliminary survey of metal concentrations in soil and vegetable samples was undertaken in the town of Zlatna, in western Romania that is dominated by a large copper smelter. One data set (town survey) consisted of soil samples taken from sites both in the centre of the town (near smelter and school grounds) and the outskirts and included those from roadside verges and wooded areas. The second data set consisted of soil samples taken from vegetable garden plots together with an associated sample of spring onion (Allium fistulosum). The aim of this study was to measure levels of the elements Cu, Zn, Pb, Cd and As in soil samples from Zlatna in general, and to assess their uptake into home grown vegetables and thus into the food chain. Concentrations of the elements of interest in soils and vegetables peaked southwest of the smelter and also in soils near the school in the town centre. Concentrations of elements in soils from the town, including those near the school, had the following ranges: Cu, 41–12,000, geometric mean 863 μg/g; Zn, 89–15,600, geometric mean 920 μg/g; Pb, 32–7860, geometric mean 740 μg/g; Cd, BDL–329.5, geometric mean 3.35 μg/g; As, 15–1440 geometric mean 223 μg/g; Thus, the residents of Zlatna are potentially exposed to levels of these elements that are higher than the recommended guideline values. Mean concentrations of the toxic elements in spring onions were: Cu, 10.2; Zn, 95; Pb, 11; Cd, 0.8; As 2.6 μg/g dry weight. 相似文献
92.
93.
Characterization of commercial kava-kava herbal drug and herbal drug preparations by means of nuclear magnetic resonance spectroscopy 总被引:1,自引:0,他引:1
Bilia AR Bergonzi MC Lazari D Vincieri FF 《Journal of agricultural and food chemistry》2002,50(18):5016-5025
The efficiency of one- and two-dimensional NMR experiments in characterizing the content of the constituents of both herbal drugs and herbal drug preparations is demonstrated for kava-kava. These experiments directly detect active constituents represented by kavalactones in both a finely powdered herbal drug and a commercial extract. In addition, NMR spectroscopy can detect all other compounds present in the extract. As previously evidenced, NMR experiments can represent a generally applicable technique for rapid screening and are a complement to the classical analytical techniques such as high-performance thin-layer chromatography, high-performance liquid chromatography, capillary gas chromatography, and electrophoresis. These experiments can be considered a very simple and fast analytical method to obtain a fingerprint of the herbal drugs and their preparations, and to quantify the content of the active principles of the extract. 相似文献
94.
Cordenunsi BR De Menezes Wenzel E Genovese MI Colli C De Souza Gonçalves A Lajolo FM 《Journal of agricultural and food chemistry》2004,52(11):3412-3416
The seeds of Parana pine (Araucaria brasiliensis syn. Araucaria angustifolia), named pinh?o, are consumed after cooking and posterior dehulling, or they are used to prepare a flour employed in regional dishes. Native people that live in the South of Brazil usually consume baked pinh?o. As a result of cooking, the white seeds become brown on the surface due to the migration of some tinted compounds present in the seed coat. In this work, the proximate composition, minerals, flavonoids, and glycemic index (GI) of cooked and raw pinh?o seeds were compared. No differences in moisture, lipids, soluble fiber, and total starch after boiling were found. However, the soluble sugars and P, Cu, and Mg contents decreased, probably as a consequence of leaching in the cooking water. Also, the boiling process modified the profile of the phenolic compounds in the seeds. No flavonols were detected in raw pinh?o seeds. The internal seed coat had a quercetin content five times higher than that of the external seed coat; also, quercetin migrated into the seed during cooking. The internal seed coat had a high content of total phenolics, and seeds cooked in normal conditions (with the seed coat) showed a total phenolics content five times higher than that of seeds cooked without the seed coat. Cooking was then extremely favorable to pinh?o seeds bioactive compounds content. The carbohydrate availability was evaluated in a short-term assay in humans by the GI. The GI of pinh?o seeds cooked with the coat (67%) was similar to that of the seeds cooked without a coat (62%) and lower than bread, showing that cooking does not interfere with starch availability. The low glycemic response can be partly due to its high content of resistant starch (9% of the total starch). 相似文献
95.
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
96.
K. M. Vlassak F. Mercante R. Straliotto A. Franco M. Vuylsteke J. Vanderleyden 《Biology and Fertility of Soils》1997,24(3):274-282
Inoculation of beans (Phaseolus vulgaris L.) with strains of R. tropici IIB and R. etli resulted in the disappearance of the R. tropici IIB stains from the nodule population and their replacement by other (non R. tropici IIB) bean symbionts (Vlassak et al. 1996). Coinoculation studies in monoxenic conditions and in soil core microcosms with
plants harvested at two different growth stages indicated that the inoculated R. tropici IIB strains CIAT899 and F98.5 possess a good intrinsic competitiveness which declines, however, at a later plant growth stage
and in soil conditions. The poor saprophytic competence of R. tropici IIB strain CIAT899 was further demonstrated by its poor survival in soil core microcosms after bean harvest. Strains were
isolated from the field plots with a 3-year bean-planting history, characterized and evaluated for their competitiveness against
R. tropici IIB strain CIAT899. Isolates from field plots, which had been repeatedly inoculated with R. tropici IIB strain CIAT899, showed a higher nodule occupancy compared to R. tropici IIB strain CIAT899, and this higher competitiveness exhibited by the field isolates might be an additional reason for the
poor performance of R. tropici IIB strain CIAT899 in the field study. Plots with and without a history of bean production revealed after 3-year bean cultivation
an almost totally different population that also significantly differed in competitiveness.
Received: 12 February 1996 相似文献
97.
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
98.
Flavonoids in vegetable foods commonly consumed in Brazil and estimated ingestion by the Brazilian population 总被引:3,自引:0,他引:3
The objective of this work was to quantify the flavonoids present in foods most commonly consumed by the Brazilian population. The predominant flavonoids found in largest abundance in all of the analyzed vegetables were glycosides of quercetin. In lettuce, a small amount of luteolin was also detected. In sweet pepper, quercetin and luteolin were both present. White onion [48-56 mg/100 g of fresh weight (FW), expressed as aglycon], red onion (40-100 mg/100 g of FW), red lettuce (67-67.2 mg/100 g of FW), arugula (41-118 mg/100 g of FW), and chicory (18-38 mg/100 g of FW) were highest in total flavonoids. In fruits, the highest concentrations of flavonoids were found in the peel (125-170 mg/100 g of FW) and pulp (35-44 mg/100 g of FW) of oranges and in some apple varieties (14-36 mg/100 g of FW). Variability in flavonoid content due to time of harvesting was high for leafy vegetables and red onions. The estimated ingestion by Brazilian population ranged from 60 to 106 mg/day. 相似文献
99.
100.
Jen JC Chan WM Bosley TM Wan J Carr JR Rüb U Shattuck D Salamon G Kudo LC Ou J Lin DD Salih MA Kansu T Al Dhalaan H Al Zayed Z MacDonald DB Stigsby B Plaitakis A Dretakis EK Gottlob I Pieh C Traboulsi EI Wang Q Wang L Andrews C Yamada K Demer JL Karim S Alger JR Geschwind DH Deller T Sicotte NL Nelson SF Baloh RW Engle EC 《Science (New York, N.Y.)》2004,304(5676):1509-1513
The mechanisms controlling axon guidance are of fundamental importance in understanding brain development. Growing corticospinal and somatosensory axons cross the midline in the medulla to reach their targets and thus form the basis of contralateral motor control and sensory input. The motor and sensory projections appeared uncrossed in patients with horizontal gaze palsy with progressive scoliosis (HGPPS). In patients affected with HGPPS, we identified mutations in the ROBO3 gene, which shares homology with roundabout genes important in axon guidance in developing Drosophila, zebrafish, and mouse. Like its murine homolog Rig1/Robo3, but unlike other Robo proteins, ROBO3 is required for hindbrain axon midline crossing. 相似文献