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1.
Minerals found in milk, such as Se, Ca, K, Zn, Mg, and P, contribute to several vital physiological processes. The aim of this study was to quantify the genetic variation in levels of Se, Ca, K, Zn, Mg, and P in milk and to quantify the between-herd variation in the levels of these minerals in milk. One morning milk sample from each of 1,860 Dutch Holstein-Friesian cows from 388 commercial herds in the Netherlands was used. Concentration of minerals was determined by inductively coupled plasma-atomic emission spectrometry. Variance components were estimated using an animal model with covariates for days in milk and age at first calving; fixed effects for season of calving and effect of test or proven bull; and random effects for animal, herd, and error. Heritability and proportion of phenotypic variation that can be explained by herd were estimated using univariate analysis. The intraherd heritability for Se was low (0.20) whereas herd explained 65% of the total variation in Se. Variation between herds most likely results from variation in Se content in the feed, which partly reflects variation in Se levels in the soil. Intraherd heritabilities for Ca, K, Zn, Mg, and P were moderate to high and were 0.57, 0.46, 0.41, 0.60, and 0.62, respectively. For Ca, K, Zn, Mg, and P, the proportions of phenotypic variation that could be explained by herd were low (0.13-0.24). This study shows that there are possibilities for altering the mineral composition of milk. For Ca, K, Zn, Mg, and P, there are good prospects for selective breeding whereas, for Se, measures at farm level may be more effective.  相似文献   

2.
Kidneys of cattle, pigs and sheep and chicken livers have been analyzed for contents of copper, chromium, manganese, nickel and zinc. Mean levels found for copper, manganese and zinc correspond well with results of earlier studies as well as with literature data. Contents measured for chromium and nickel are very low: for nickel in porcine kidneys and sheep kidneys median values of 0.045 and 0.022 mg/kg were found. Average contents for nickel in the other tissues and for chromium in all tissues investigated are below 0.01 mg/kg fresh mass. These results for chromium and nickel correspond well with recent results from Sweden, but are lower than most published values.  相似文献   

3.
Summary Kidneys of cattle, pigs and sheep and chicken livers have been analyzed for contents of copper, chromium, manganese, nickel and zinc. Mean levels found for copper, manganese and zinc correspond well with results of earlier studies as well as with literature data. Contents measured for chromium and nickel are very low: for nickel in porcine kidneys and sheep kidneys median values of 0.045 and 0.022 mg/kg were found. Average contents for nickel in the other tissues and for chromium in all tissues investigated are below 0.01 mg/kg fresh mass. These results for chromium and nickel correspond well with recent results from Sweden, but are lower than most published values.
Kupfer, Chrom, Mangan, Nickel und Zink in Nieren von Rindern, Schweinen und Schafen und in Hühnerlebern in den Niederlanden
Zusammenfassung Nieren von Rindern, Schweinen und Schafen und Hühnerlebern wurden auf den Gehalt an Kupfer, Chrom, Mangan, Nickel und Zink untersucht. Die Durchschnittswerte für Kupfer, Mangan und Zink stimmen gut mit Ergebnissen früherer Untersuchungen und mit Literaturwerten überein. Die gemessenen Werte für Chrom und Nickel sind sehr niedrig; für Nickel in Schweine- und Schafnieren wurden mediane Gehalte von 0,045 und 0,022 mg/kg gefunden. Durchschnittswerte für Nickel in den übrigen Geweben und für Chrom in allen untersuchten Geweben liegen unterhalb 0,01 mg/kg Frischsubstanz. Diese Werte für Chrom und Nickel stimmen gut mit neueren Daten aus Schweden überein, aber sie sind niedriger als die meisten Literaturdaten.
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4.
采用微波消解-电感耦合等离子体质谱法测定了41个牌号烤烟型卷烟和雪茄烟样品烟丝中的锂、铬、镍、铜、砷、硒、钼、镉、铊和铅含量,并按照类型和价位对卷烟中这10种有害元素含量进行了统计分析。结果发现:①卷烟中锂和铜的含量较高,铊的含量很低,铬、镍、镉、铅、砷、硒和钼7种元素的平均含量为0.55~4.42μg/g;②雪茄烟中铬、镍、砷、钼、镉、铊和铅的含量一般高于烤烟型卷烟,而硒元素的含量则相反,但差别较小;烤烟型卷烟中锂和铜的含量与雪茄烟没有显著差异;③高档卷烟中的锂、镍、镉、铊和铬含量较低,而砷、铅的含量较高;不同价位卷烟的铜、硒和钼含量差异不显著。  相似文献   

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6.
In the present study ninety nine polished white rice samples were collected in three areas, all over Lorestan Province located in the west of Iran, and analysed for six elements by Flame Atomic Absorption Spectrometry (FAAS). For individual elements, Zinc (Zn) showed the highest concentration among the analysed essential elements with a mean of 28.6 mg kg?1 and next to copper (Cu) of 22.8 mg kg?1. Analysis of the essential and toxic elements for possible inter-area variation by ANOVA showed that there are significant differences between the areas. There was no significant difference between areas for Zn concentrations. Most of the samples nearly contained world wide average concentration of iron (Fe) and Zn in rice grains that were reported by various researches. But, the content of calcium (Ca) in the rice samples produced in Lorestan Province were much lower than other countries, meanwhile Cu concentrations were much higher than other studies. Cadmium (Cd) and Lead (Pb) concentrations in the sampled rice were lower in comparison with their upper limits (0.1 and 0.2 mg kg?1 for Cd and Pb, respectively) approved by Iranian Ministry of Health. Therefore, it can be concluded that there is no health problems result from Lorestan rice consumption, for these two elements.  相似文献   

7.
Manganese, copper, zinc, iron, cadmium, mercury and lead concentrations have been determined in muscle meat, livers and kidneys of ducks, geese, chickens, hens, rabbits and sheep slaughtered in the northern part of Poland in 1987. The mean values obtained related to wet weight for muscle meat, livers and kidneys of animals were: 0.11-0.27, 0.73-3.3 and 0.90-1.9 mg/kg Mn; 0.52-7.3, 3.8-88 and 2.8-15 mg/kg Cu; 5.7-40, 20-45 and 21-30 mg/kg Zn; 10-35, 27-83 and 50-180 mg/kg Fe; less than 5-5, 16-140 and 250-5100 micrograms/kg Cd; less than 1-3, 2-10 and 5-12 micrograms/kg Hg; and less than 10-20, 100-210 and 120-1300 micrograms/kg Pb, respectively. Substantial differences have been found in the mean copper concentration in muscle meat, livers and kidneys, zinc and iron in muscle meat, and cadmium in kidneys, between some of the species examined. The mean and maximum concentrations of mercury and lead found in muscle meat and organs of animals in the present study were low, and only in the case of cadmium were somewhat higher values found in kidneys of rabbit and hen. The results obtained are compared with the literature data on the concentrations of the metals examined in muscle meat, livers and kidneys of poultry, rabbit and sheep in Poland or elsewhere.  相似文献   

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Summary The levels of zinc, copper, manganese, selenium, chromium, nickel, cobalt, and aluminium were determined in samples of meat, liver and kidney from pigs and cattle from Swedish slaughterhouses. The results have been compared with those reported from other investigations carried out in recent years. For zinc, copper, manganese and selenium, the mean levels found in the different tissues were very similar to those reported in previous studies. The mean levels of chromium and nickel were found to be in the range <0.010–0.015 mg/kg, regardless of the type of tissue. Cobalt levels ranged from 0.001 to 0.043 mg/kg, the highest levels being in the liver samples. The mean levels of aluminium were between 0.024 and 0.068 mg/kg. Tissues from cattle contained approximately twice as much aluminium as tissues from pigs. Analytical quality assurance was carried out by analysing standard reference materials. A great effort was made to minimize and check contamination. This may partly explain the fact that the levels of chromium, nickel, and aluminium found in the present study are among the lowest reported.
Gehalt an Zink, Kupfer, Mangan, Selen, Chrom, Nickel, Kobalt und Aluminium in Fleisch, Leber und Nieren von schwedischen Schweinen und Rindvieh
Zusammenfassung Es wurde der Gehalt an Zink, Kupfer, Mangan, Selen, Chrom, Nickel, Kobalt und Aluminium in Fleisch, Leber und Nieren vom Schwein und Rind aus schwedischen Schlachthäusern bestimmt. Diese Ergebnisse wurden mit denen anderer Untersuchungen verglichen. Die Durchschnittswerte für Zink, Kupfer, Mangan und Selen in verschiedenen Geweben waren ungefähr die gleichen wie in früheren Untersuchungen; die für Chrom und Nickel lagen alle im Intervall <0,010 bis zu 0,015 mg/kg, unabhängig von der Art der Gewebe, und die für Kobalt zwischen 0,001 und 0,043 mg/kg, mit den höchsten Werten in der Leber. Für Aluminium ergaben sich Durchschnittswerte zwischen 0,024 und 0,068 mg/kg, wobei die Gewebe vom Rind ungefahr doppelt so viel Aluminium enthalten wie die Gewebe vom Schwein. Die analytische Qualitätskontrolle wurde mit Referenzmaterial durchgeführt. Viel Arbeit wurde zur Minimierung und Kontrolle der Kontamination aufgewendet. Das kann zu einem Teil erklären, daß die Werte von Chrom, Nickel und Aluminium unserer Untersuchung zu den niedrigsten bisher veröffentlichten Werten gehören.
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11.
The levels of zinc, copper, manganese, selenium, chromium, nickel, cobalt, and aluminium were determined in samples of meat, liver and kidney from pigs and cattle from Swedish slaughterhouses. The results have been compared with those reported from other investigations carried out in recent years. For zinc, copper, manganese and selenium, the mean levels found in the different tissues were very similar to those reported in previous studies. The mean levels of chromium and nickel were found to be in the range less than 0.010-0.015 mg/kg, regardless of the type of tissue. Cobalt levels ranged from 0.001 to 0.043 mg/kg, the highest levels being in the liver samples. The mean levels of aluminium were between 0.024 and 0.068 mg/kg. Tissues from cattle contained approximately twice as much aluminium as tissues from pigs. Analytical quality assurance was carried out by analysing standard reference materials. A great effort was made to minimize and check contamination. This may partly explain the fact that the levels of chromium, nickel, and aluminium found in the present study are among the lowest reported.  相似文献   

12.
Although various single-concentration measurements of pharmaceuticals are available in the literature, detailed information on the variation over time of the concentration and the load in wastewater effluents and rivers and on the fate of these compounds in the aquatic environment are lacking. We measured the concentrations of six pharmaceuticals, carbamazepine, clofibric acid, diclofenac, ibuprofen, ketoprofen, and naproxen, in the effluents of three wastewater treatment plants (WWTPs), in two rivers and in the water column of Lake Greifensee (Switzerland) over a time period of three months. In WWTP effluents, the concentrations reached 0.95 microg/L for carbamazepine, 0.06 microg/L for clofibric acid, 0.99 microg/L for diclofenac, 1.3 microg/L for ibuprofen, 0.18 microg/L for ketoprofen, and 2.6 microg/L for naproxen. The relative importance in terms of loads was carbamazepine, followed by diclofenac, naproxen, ibuprofen, clofibric acid, and ketoprofen. An overall removal rate of all these pharmaceuticals was estimated in surface waters, under real-world conditions (in a lake), using field measurements and modeling. Carbamazepine and clofibric acid were fairly persistent. Phototransformation was identified as the main elimination process of diclofenac in the lake water during the study period. With a relatively high sorption coefficient to particles, ibuprofen might be eliminated by sedimentation. For ketoprofen and naproxen, biodegradation and phototransformation might be elimination processes. For the first time, quantitative data regarding removal rates were determined in surface waters under real-world conditions. All these findings are important data for a risk assessment of these compounds in surface waters.  相似文献   

13.
Holsteins (HH), Jerseys (JJ), and their crosses in first (n=157) and second (n=107) lactation were used to determine if reproduction, progesterone (P4), insulin-like growth factor 1 (IGF-1), insulin, nonesterified fatty acids (NEFA), and milk production differed between genetic groups. Thirty-four cows were Holstein-Jersey (HJ) crosses, 46 were Jersey-Holstein (JH) crosses, 48 were purebred Holsteins (HH), and 29 were purebred Jerseys (JJ) in first lactation, whereas the second-lactation animals included 23 HJ, 35 JH, 35 HH, and 14 JJ. Blood samples were collected weekly for the first 10 wk postpartum. Analyses were conducted using the MIXED, chi-square, and GLIMMIX procedures (SAS Institute Inc., Cary, NC). Seasons of calving were cold (November to May) and hot (June to October) and were combined with year to form 8 year-seasons. Days open and number of services were affected by genetic group. The HH were open 169±8 d, which was greater than HJ (143±9 d), JJ (132±10 d), and JH (127±8 d). The HH had 2.4±0.1 services per pregnancy, which was greater than JH (1.9±0.1), but not different from HJ (2.1±0.2) or JJ (2.1±0.2). Concentrations of NEFA were greater in lactation 2 (0.52±0.02 mEq/L) than in lactation 1 (0.45±0.02 mEq/L) and decreased over the 10-wk period. Concentrations of NEFA were greater in the cold season except in yr 3. Insulin in lactation 1 (0.81±0.03 ng/mL) was greater than in lactation 2 (0.72±0.03 ng/mL); insulin decreased to wk 2 then gradually increased. The HJ had the greatest insulin concentrations (0.87±0.04 ng/mL) and the JJ had the lowest (0.66±0.04 ng/mL), and IGF-1 gradually increased over the 10-wk period. Milk production (actual yield in the first 305 d, not adjusted for fat and protein) was affected by genetic group, lactation number, year-season, and wk 1 insulin. The HH produced 10,348±207 kg of milk, which was greater than the HJ (9,129±230 kg), the JH (9,384±190 kg), and the JJ (7,080±240 kg). Milk production in lactation 2 (9,676±163 kg) was greater than that in lactation 1 (8,294±160 kg). The JJ (10.3±4.7%) had the highest frequency of mastitis. The chance of getting mastitis for HH (1.1±0.9%) differed from that for HJ (9.4±4.1%), JH (8.1±3.4%), and JJ (10.3±4.7%). Genetic group affected hormones and metabolites, which may partially explain differences in reproductive measures and milk yield.  相似文献   

14.
Flue gas from coal combustion contains significant amounts of volatile toxic trace elements such as arsenic (As), selenium (Se), and mercury (Hg). The capture of these elements in the flue gas desulphurization (FGD) scrubber unit has resulted in generation of a metal-laden residue. With increasing reuse of the FGD residues in beneficial applications, it is important to determine metal speciation and mobilityto understand the environmental impact of its reuse. In this paper, we report the solid phase speciation of As, Se, and Hg in FGD residues using X-ray absorption spectroscopy (XAS), X-ray fluorescence spectroscopy (XRF), and sequential chemical extraction (SCE) techniques. The SCE results combined with XRF data indicated a strong possibility of As association with iron oxides, whereas Se was distributed among all geochemical phases. Hg appeared to be mainly distributed in the strong-complexed phase. XRF images also suggested a strong association of Hg with Fe oxide materials within FGD residues. XAS analysis indicated that As existed in its oxidized state (As(V)), whereas Se and Hg was observed in primarily reduced states as selenite (Se(IV)) and Hg(I), respectively. The results from the SCE and variable pH leaching tests indicated that the labile fractions of As, Se, and Hg were fairly low and thus suggestive of their stability in the FGD residues. However, the presence of a fine fraction enriched in metal content in the FGD residue suggested that size fractionation is important in assessing the environmental risks associated with their reuse.  相似文献   

15.
Role of polysaccharides in food,digestion, and health   总被引:1,自引:0,他引:1  
Polysaccharides derived from plant foods are major components of the human diet, with limited contributions of related components from fungal and algal sources. In particular, starch and other storage carbohydrates are the major sources of energy in all diets, while cell wall polysaccharides are the major components of dietary fiber. We review the role of these components in the human diet, including their structure and distribution, their modification during food processing and effects on functional properties, their behavior in the gastrointestinal tract, and their contribution to healthy diets.  相似文献   

16.
目的研究福建省市售茶叶中金属元素含量情况,通过分析茶叶中重金属含量情况,评估其对人体的健康风险情况。方法在福建省市场随机抽取不同品种茶叶98份,用微波消解法处理茶叶,电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry,ICP-MS)检测茶叶中铝、铅、砷、汞、铬、镉的含量。结果98批市售茶叶中的铅、砷、汞、铬、镉5种重金属元素含量都在国家标准范围之内,目前暂无茶叶中铝含量相关限量标准,但其危害作用有限。98份市售茶叶中铅、砷、铬、铝检出率均为100%,铬、汞的检出率分别为95.9%、37.8%。各元素靶标危害系数(target hazard quotient,THQ)排名依次为铝>铬>砷>铅>镉>汞,危害指数(hazard Index,HI)为0.2589,铝对危害指数的贡献率为45.2%。按照不同茶叶种类进行分类,其危害指数排名依次为黑茶>乌龙茶>绿茶>红茶。按照茶叶产地进行分类,其危害指数排名依次为云南>福建>浙江。结论福建省市售茶叶中这6种金属元素存在一定程度的污染,但危害指数为0.2589,小于1,对人们的健康风险较低,但仍应持续监测茶叶中金属元素的含量情况。  相似文献   

17.
Pure water has been used to dechlorinate aliphatic organics without the need for catalysts or other additives. Dehydrohalogenation (loss of HCI with the formation of a double bond) occurred at temperatures as low as 105-200 degrees C for 1,1,2,2-tetrachloroethane, lindane (1,2,3,4,5,6-hexachlorocyclohexane, gamma-isomer), and dieldrin (1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro-endo, exo-1,4:5,8-dimethanonaphthalene). Complete loss of the parent compounds was achieved in less than 1 h at 150, 200, and 300 degrees C for 1,1,2,2-tetrachloroethane, lindane, and dieldrin, respectively. The initial dechlorination of lindane had an activation energy of 84 kJ mol(-1) with an Arrhenius pre-exponential factor of 1.5 x 10(6) s(-1). Dehydrohalogenation of lindane formed trichlorobenzenes, followed by subsequent hydrolysis and hydride/chloride exchange to form chlorophenols, lower chlorobenzenes, and phenol as the major final product. Reaction of poly(vinyl chloride) at 300 degrees C for 1 h formed aromatic hydrocarbons ranging from benzene to anthracene and a char residue with a ca. 1:1 carbon-to-hydrogen ratio (mol/mol). The residue contained <1 wt % of chlorine compared to 57 wt % chlorine in the original polymer. All compounds tested yielded chloride ion as the major product (at higher temperatures), indicating that complete dechlorination of some aliphatic organochlorines may be feasible.  相似文献   

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Carotenoids are fascinating compounds that can be converted into many others, including retinoids that also play key roles in many processes. Although carotenoids are largely known in the context of food science, nutrition, and health as natural colorants and precursors of vitamin A (VA), evidence has accumulated that even those that cannot be converted to VA may be involved in health‐promoting biological actions. It is not surprising that carotenoids (most notably lutein) are among the bioactives for which the need to establish recommended dietary intakes have been recently discussed. In this review, the importance of carotenoids (including apocarotenoids) and key derivatives (retinoids with VA activity) in agro‐food with relevance to health is summarized. Furthermore, the European Network to Advance Carotenoid Research and Applications in Agro‐Food and Health (EUROCAROTEN) is introduced. EUROCAROTEN originated from the Ibero‐American Network for the Study of Carotenoids as Functional Food Ingredients (IBERCAROT).  相似文献   

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