Phytotoxic Effects of Cd, Zn, Pb, Cu and Fe on Sinapis Alba L. Seedlings and their Accumulation in Roots and Shoots

The inhibitory effects of Cd, Cu, Zn, Pb, and Fe on root elongation, contents of photosynthetic pigments, and metal accumulation in the roots and shoots of Sinapis alba were assessed. On the basis of growth inhibition metals can be arranged in a order Cu > Cd > Fe = Zn > Pb. All the metals, except Fe, were accumulated in significantly higher amount in the roots than in the shoots. Cd, Zn, Cu and Pb reduced chlorophyll a, and especially chlorophyll b content, and Zn and Pb reduced the carotenoid content, but less than that of chlorophyll a+b. The plants contained the highest concentration of Cd, and the lowest concentration of Zn.     

叶面配施镁锌钼对银杏苗叶生长和药用品质的影响

以两年生银杏苗为研究对象,采用室内模拟与盆栽试验相结合的方法,研究了叶面配施低、中、高浓度的镁、锌、钼对银杏叶产量和药用成分含量及其产量的影响,以明确叶用银杏叶面微肥中镁锌钼的适宜浓度。结果显示:(1)镁锌钼配施能提高单叶面积、叶片厚度、单株叶面积和叶生物量,并以配施组合Mo3(2%Mg+0.3%Zn+0.1%Mo)对叶生物量的提高幅度较大(64.9%)。(2)中锌中钼配施镁肥对银杏叶绿素、可溶性糖和可溶性蛋白质含量的正效应随着镁肥喷施浓度的增加而降低,中镁中钼配施锌肥、中镁中锌配施中钼对叶片叶绿素、可溶性糖含量的正效应随着配施肥料浓度的升高而降低,而可溶性蛋白含量与配施肥料浓度呈正相关。(3)镁锌钼配施能提高叶片总黄酮、萜内酯含量,以及单株总黄酮和萜内酯产量,以配施组合Mo3对单株总黄酮、萜内酯产量的提高幅度最大,分别为2.96倍和1.70倍。(4)配施高浓度的肥料(Mg4、Zn4和Mo4)不同程度地降低了镁锌钼配施对部分指标的正效应。研究表明,配施适当浓度的镁锌钼叶面肥可在一定程度促进银杏苗叶绿素合成,上调可溶性糖和可溶性蛋白质等初生代谢物质积累,改善其叶片生长和药用品质,提高叶产量及药用品质构成要素;微肥2%Mg+0.3%Zn+0.1%Mo是本试验条件下提高银杏叶产量、药用成分含量和产量较为理想的叶肥组合。     

Effect of magnesium deficiency on enterocyte Ca, Fe, Cu, Zn, Mn and Se content

In previous studies based on indirect procedures, we reported that Mg deficit increased the bioavailability of a number of elements such as calcium, zinc, iron, copper, manganese and decreased selenium absorption. The present study was designed to verify these findings by direct methods. We investigated the effect of dietary magnesium deficiency on enterocyte Ca, Fe, Zn, Cu, Mn and Se concentrations. Male Wistar rats were fed a Mg-deficient diet (129 mg Mg/kg food) for 70 days. Whole enterocytes from the upper jejunum were isolated and Ca, Fe, Zn, Cu, Mn and Se were determined. The results were compared with findings in a control group that was pair-fed with an identical diet except that it covered this species's nutritional requirements for Mg (480 mg Mg/kg food). The Mg-deficient diet significantly increased enterocyte content of Ca, Fe, Zn, Cu and Mn; however, we found no significant changes in the Se content of these cells. These data support the results obtained by indirect methods.     

Metabolism of the Fe, Cu, Zn, Mg, MN and Co in the ovum of Cancer irroratus (decapod crustacean)]

The concentrations of Fe, Cu, Zn, Mn and Co in the eggs of Cancer irroratus show variations in relation with time running out after laying, that is to say with embryogenesis. The increase of the rates of Fe, Mn and Mg is independant of the variations of the water content. Inversely, the decrease of Cu and Zn concentrations is in close relation with the increase of water content during the same period. The increase of Fe, Mn and Mg concentrations seems to be essentially under the dependance of physico-chemical, rather than biochemical, process in connection with the chitinous nature of the membranes surrounding the egg.     

Distribution of N,P, K,Ca, Mg,S, Zn,Fe, Mn and Cu in groundnut

Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.     

Effects of exogenous nitric oxide on photosynthesis,antioxidative ability,and mineral element contents of perennial ryegrass under copper stress

A hydroponics experiment was conducted to test the effects of sodium nitroprusside (SNP, a donor of NO) supplied with different concentrations on copper (Cu) toxicity in ryegrass seedlings (Lolium perenne L.). Excess Cu (200 µM) reduced chlorophyll content, resulting a decrease in photosynthesis. Cu stress induced the production of hydrogen peroxide (H₂O₂) and superoxide anion (O₂^{? ?}), leading to malondialdehyde (MDA) accumulation. Furthermore, activities of antioxidant enzymes in Cu-treated seedlings such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were decreased. In addition, Cu stress inhibited the uptake of K, Mg, Fe, and Zn and increased Ca content in roots. Moreover, in leaves of Cu-stressed seedlings, K, Fe, and Zn contents were decreased and the contents of Ca and Mg were not affected significantly. In Cu-treated seedlings, Cu concentration in roots was higher than in leaves. Addition of 50, 100, 200 µM SNP in Cu-mediated solutions increased chlorophyll content and photosynthesis, improved antioxidant enzyme activities, reduced Cu-induced oxidative damages, kept intracellular ion equilibrium under Cu stress, increased Cu concentration in roots and inhibited Cu accumulation in leaves. In particular, addition of 100 µM SNP had the best effect on promoting growth of ryegrass seedlings under Cu stress. However, the application of 400 µM SNP had no obvious alleviating effect on Cu toxicity in ryegrass seedlings.     

Effects of iron,copper, zinc,calcium, and magnesium on human lymphocytes in culture

The effects of simultaneous changes of calcium, magnesium, iron, copper, and zinc concentrations were evaluated in normal human T and B lymphocytes, cultured in cation-depleted media. Optimal concentrations for thymidine incorporation (TI) in both cell populations were Fe and Zn 15 μM and Cu 5 μM; for t cells Ca 2 mM and Mg 4 mM; for B cells Ca 4 mM and Mg 6 mM. TI decreased with increasing molarity of cations and the decrease was particularly apparent with Cu. Minimal amounts of Ca and Mg (0.5 mM) were necessary for growth, even in presence of optimal concentrations of Fe, Cu, and Zn. Fe and Cu showed synergistic stimulatory effects at low concentrations and synergistic inhibitory effects at high concentrations. Antagonism between Fe and Zn, Cu and Zn, and Ca and Zn was also demonstrated. CD4/CD8 increased with PHA stimulation in presence of Zn, and decreased with ConA stimulation in presence of Zn or Fe. The results demonstrate: (1) the relationship and interdependence of Fe, Cu, and Zn concentrations in modulating the growth of normal lymphocytes; (2) the stimulatory effects of Fe on B cells and Zn on CD8 positive cells; (3) the inhibitory effect of Cu at concentrations lower than those of Fe and Zn; (4) the requirement of Ca and Mg in certain concentration and ratio for the action of the other cations; and (5) the Ca and Mg requirement for the growth of B cells higher than T cells.     

Cadmium Toxicity: The effect on Macro- and Micro-Nutrient Contents in Soybean Seedlings

The effect of Cd (10, 100, and 200 M) on tissue contents of macronutrients (N, P, K, Ca, Mg) and micronutrients (Fe, Zn, Cu, Mn) was investigated in hydroponically grown soybean (Glycine max) seedlings. Concentration changes of analysed elements observed against increasing Cd accumulation indicated that acute Cd-phytotoxic effect monitored through chlorophyll content was not a consequence of nutrient deficiency.     

Floral analysis as a tool to diagnose iron chlorosis in orange trees

A three-year field experiment was conducted in a commercial orange grove [Citrus sinensis (L.) Osb. cv. `Valencia late' grafted on Citrange Troyer] established on a calcareous soil in the south of Portugal, to investigate if flower analysis could be used to diagnose lime-induced iron chlorosis. In April, during full bloom, flowers and leaves were collected from 20 trees. Leaf samples were again collected from the same trees in May, June, July and August. Total chlorophyll was estimated in all the leaves sampled for foliar analysis, using a SPAD-502 apparatus. Leaves and flowers were analysed for N, P, K, Ca, Mg, Fe, Zn, Mn and Cu. Principal Component Analysis was used to evaluate the variation of nutrient concentrations in flowers, and linear regressions were established between these and the chlorophyll content of leaves 90 days after full bloom. Evaluation of the best-fit equation was carried out using separate data obtained from other groves. Variation in the pattern of floral mineral composition in the flowers showed contrasts between the increase in N, P and K and that of Ca, Fe and Zn, while the concentration of Mg, Mn and Ca varied synchronously. The ratio of Mg:Zn in flowers explained about half of the variation of chlorophyll in leaves later in the season. A ratio below 100 indicated that trees would develop iron chlorosis, while with a ratio above 200 leaves would remain green. An early prognosis of iron chlorosis based on floral analysis can benefit growers, since it allows them to apply treatments in time to prevent loss of fruit yield and quality due to iron chlorosis.     

Bovine heart cytochrome c oxidase preparations contain high affinity binding sites for magnesium as well as for zinc, copper, and heme iron

Metal contents of six bovine heart cytochrome c oxidase preparations were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Magnesium is present in consistent amounts reflected by Fe/Mg and Mg/Zn ratios of 2.06 +/- 0.18 and 1.10 +/- 0.14, respectively. More copper than iron is always present; the average Cu/Fe atom ratio is 1.27 +/- 0.10. Calcium is found in significant but variable amounts. Mg, Zn, Fe, and Cu are each bound with high affinity as shown by a resistance to removal upon dialysis against various media. The Cu in excess of Fe, the Mg, and the Zn may each have catalytic and/or structural roles in the oxidase. The observed metal stoichiometry suggests that a dimeric catalytic unit with 5 Cu, 4 Fe, 2 Zn, and 2 Mg may be present in the inner mitochondrial membrane to carry out O2 reduction and H+ pumping.     

Effect of various degrees and duration of magnesium deficiency on lipid peroxidation and mineral metabolism in rats

Severe magnesium (Mg) deficiency changed mineral homeostasis, increased lipid peroxidation, and reduced Mg²⁺/Ca²⁺ antagonism. To investigate whether the pathobiochemical effects directly correlate with the degree of Mg deficiency or whether there might be a threshold for significant alterations, diets with 70, 110, 208, 330, and 850 ppm of Mg were fed to growing Wistar rats. After feeding the diets for 0, 10, 20, and 30 days, parameters of free radical action (malondialdehyde and vitamin E content), mineral content (Mg, Ca, Fe, Zn) in various tissues (liver, spleen, heart, kidney, muscle) and plasma parameters (Mg, Ca, Fe, Zn, alanine- and aspartate-aminotransferase, tumor necrosis factor- [TNF-] were analyzed. The tissue Mg content was either unchanged or only slightly reduced in severe Mg deficiency. The iron (Fe) content rose when the extracellular Mg²⁺ concentration was below 0.25 mmol/L. There was a close positive correlation between the tissue Fe and the malondialdehyde content and a negative correlation between the malondialdehyde and the vitamin E content. Below the threshold of about 0.25 mmol/L of plasma Mg²⁺ concentration, elevated zinc (Zn) concentrations were found in liver and kidney as well as in plasma increased transaminases and TNF-. The same threshold could be observed for the increase of tissue calcium (Ca) content, except in the kidney where calcifications were found already in less severe Mg deficiency. Concerning changed mineral homeostasis with subsequent lipid peroxidation and membrane damage, plasma Mg²⁺ concentrations must be below 0.25 mmol/L: above this threshold effects of Mg deficiency alone can be compensated.     

Age-Related Changes of Elements and Relationships Among Elements in Human Hippocampus, Dentate Gyrus, and Fornix

To elucidate compositional changes of the limbic system with aging, the authors investigated age-related changes of elements in the hippocampus, dentate gyrus, and fornix and the relationships among elements by direct chemical analysis. After ordinary dissections at Nara Medical University were finished, the hippocampi, dentate gyri, and fornices were resected from identical cerebra of the subjects which consisted of 23 men and 23 women, ranging in age from 70 to 101 years. After ashing with nitric acid and perchloric acid, element contents were determined by inductively coupled plasma-atomic emission spectrometry. The average contents of P, Zn, and Na were significantly less in both the hippocampi and dentate gyri compared with the fornices. It was found that the Ca and Mg contents increased significantly in the hippocampus with aging; the P content increased significantly in the dentate gyrus with aging, whereas the Na content decreased in the dentate gyrus with aging; and the Mg content increased significantly in the fornix with aging. Regarding the relationships among elements, a significant direct correlation between Ca and Fe contents and an extremely significant inverse correlation between P and Zn contents were found in both the hippocampi and dentate gyri. In addition, a significant direct correlation between P and Mg contents was found in both the hippocampi and fornices. Pearson's correlation was used to examine whether there were elements with significant correlation among the hippocampus, dentate gyrus, fornix, and mammillary body. Significant correlations were found in five elements of Ca, P, Mg, Zn, and Fe except for S and Na among the hippocampus, dentate gyrus, and mammillary body with one exception. Regarding the fornix, significant correlations were found in two elements of P and Fe between the fornix and hippocampus, dentate gyrus, or mammillary body.     

盐胁迫对苹果器官中钙镁铁锌含量的影响

以盆栽2年生富士苹果树(砧木为平邑甜茶M.hupehensisReld)为试材,研究了盐胁迫对苹果矿质营养平衡的影响.结果表明,在盐胁迫下,苹果各器官不同时期的单位干样中Ca、Mg、Fe和Zn含量的平均值没有明显变化,但各元素与Na的比值明显下降,特别是在高盐(3‰NaCl)胁迫下下降更为明显,从而破坏了树体内元素平衡.在无盐和盐胁迫下,苹果各器官中Ca含量的顺序为主干韧皮部＞叶片、新梢＞根＞主干木质部;Mg含量为新梢、根＞主干木质部、主干韧皮部、叶片;Fe含量为根＞叶片＞主干韧皮部、新梢＞主干木质部;Zn含量为新梢＞叶片＞根、主干韧皮部＞主干木质部.与对照相比,器官中各元素含量在胁迫期间表现出不同程度的波动性.     

The limnology of a Thermal Lake: Lake Rotowhero,New Zealand: I. General description and water chemistry

The topography, morphology, hydrography, temperature conditions and water chemistry of an acid thermal lake, Lake Rotowhero. North Island, New Zealand, were studied and related to lake biology. Results are given for analyses of O₂, pH, conductivity, Ca, Mg, Na, K, SO₄, Cl, Si, total-P, reactive-P, NH₄-N, NO₃ N, NO₂-N As, Fe, Mn, Zn, Cu, total dissolved solids, chlorophyll and total pigment. Sediment mineralogy and total carbon content are mentioned.     

Effects of zinc toxicity on sugar beet (Beta vulgaris L.) plants grown in hydroponics

The effects of high Zn concentration were investigated in sugar beet ( Beta vulgaris L.) plants grown in a controlled environment in hydroponics. High concentrations of Zn sulphate in the nutrient solution (50, 100 and 300 μ m ) decreased root and shoot fresh and dry mass, and increased root/shoot ratios, when compared to control conditions (1.2 μ m Zn). Plants grown with excess Zn had inward-rolled leaf edges and a damaged and brownish root system, with short lateral roots. High Zn decreased N, Mg, K and Mn concentrations in all plant parts, whereas P and Ca concentrations increased, but only in shoots. Leaves of plants treated with 50 and 100 μ m Zn developed symptoms of Fe deficiency, including decreases in Fe, chlorophyll and carotenoid concentrations, increases in carotenoid/chlorophyll and chlorophyll a / b ratios and de-epoxidation of violaxanthin cycle pigments. Plants grown with 300 μ m Zn had decreased photosystem II efficiency and further growth decreases but did not have leaf Fe deficiency symptoms. Leaf Zn concentrations of plants grown with excess Zn were high but fairly constant (230–260 μg·g⁻¹ dry weight), whereas total Zn uptake per plant decreased markedly with high Zn supply. These data indicate that sugar beet could be a good model to investigate Zn homeostasis mechanisms in plants, but is not an efficient species for Zn phytoremediation.     

南瓜茎、叶、花的营养成分分析

对南瓜茎、叶、花等部位进行了粗脂肪、粗蛋白、粗纤维、总糖、Vc等主要营养成分和K、Na、Ca、Mg、Zn等矿质元素的测定。结果表明,南瓜茎、叶、花营养丰富,各种营养成分较为全面。南瓜叶中粗脂肪、粗蛋白、Vc、K、Ca、Mg、Mn、Fe、Zn等成分含量均高于南瓜茎和南瓜花。与其他8种常见蔬菜相比,主要营养成分和矿质元素含量也远远高于这8种蔬菜。为南瓜茎、叶、花的菜用价值提供了科学依据,也为增加人们的膳食营养、改变餐桌食品花样、开发蔬菜资源及其利用价值提供了参考。     

锌和铁缺乏对枳生理指标、矿物质含量及叶片超微结构的影响

采用营养液培养法,研究了缺锌(0μmol·L-1 Zn2+)、缺铁(0μmol.L-1 Fe-EDTA)条件下柑橘砧木枳的生理胁迫反应.结果表明:1)锌、铁缺乏使枳生物量与根系活力均显著下降,叶片与根系中的SOD活性明显上升;叶片与根系中的POD活性在缺锌下显著增高,但在缺铁胁迫下显著降低;缺锌处理的根系CAT活性显著上升,但缺铁处理下的CAT活性与对照无显著差异.2)缺铁处理的根部K、Mg、P含量及缺锌处理的地上部K含量均显著降低;缺铁处理的根部和地上部Zn、Cu含量以及缺锌处理的根部Fe、Mn及地上部Mn含量均显著增高.3)叶肉细胞超微结构变化显著,缺铁胁迫下细胞器受损程度较重,如叶绿体、线粒体空泡化严重,叶绿体膜及类囊体片层模糊,质体小球明显增多,无淀粉粒;而缺锌处理时叶绿体基粒片层排列松散、数目明显减少,质体小球明显增多.     

The Content of Elements in Infant Formulas and Drinks Against Mineral Requirements of Children

The present study aimed at analysing the content of fluorine (F), calcium (Ca), magnesium (Mg), iron (Fe) and zinc (Zn) in the drinks for children and infant formulas, a popular supplement or substitute for breast milk produced from cow milk on an industrial scale. Ca, Mg, Zn and Fe concentrations were determined using atomic absorption spectrophotometer, while F levels using a potentiometric method. F levels in the examined formula samples increased with the intended age range, until the intended age of 1 year, and then decreased. A lower content of Ca, Mg and Zn was observed in formulas intended for children <1 year of age and higher for older children. Fe content increased with the age range. A statistically significant higher content of Ca, Mg, Zn and Fe in samples intended for children with phenylketonuria in comparison to those intended for healthy children or children with food allergies was noted. The content of the analysed elements in juices and nectars showed the highest contents in products intended for infants (under 6 months of age). The lowest levels of elements tested were found in drinks for children over 6 months of age. In conclusion, the concentrations of the examined elements in infant formulas and juices for children were decidedly greater than the standards for the individual age groups. Although the absorption of these elements from artificial products is far lower than from breast milk, there is still the fear of consequences of excessive concentrations of these minerals.     

Effects of Boron on Growth, and Chlorophyll and Mineral Contents of Shoots of the Apple Rootstock MM 106 cultured in vitro

The in vitro cultures of apple rootstock MM 106 produced the highest fresh mass (FM) when 0.1 mM B was included in the culture medium. By increasing B concentration of the culture medium from 0.1 to 6.0 mM, FM and contents of B, P, Ca, and Mg in explants increased, whereas K, Fe, Mn, and Zn contents decreased. SPAD units of leaves characterizing chlorophyll contents declined as B concentration of the culture medium increased from 0.1 to 6.0 mM.     

Accumulation of cadmium, zinc, and copper by Helianthus annuus L.: impact on plant growth and uptake of nutritional elements

We investigated the effects on physiological response, trace elements and nutrients accumulation of sunflower plants grown in soil contaminated with: 5 mg kg(-1) of Cd; 5 and 300 mg kg(-1) of Cd and Zn, respectively; 5, 300, and 400 mg kg(-1) of Cd, Zn, and Cu, respectively. Contaminants applied did not produce large effects on growth, except in Cd-Zn-Cu treatment in which leaf area and total dry matter were reduced, by 15%. The contamination with Cd alone did not affect neither growth nor physiological parameters, despite considerable amounts of Cd accumulated in roots and older leaves, with a high bioconcentration factor from soil to plant. By adding Zn and then Cu to Cd in soil, significant were the toxic effects on chlorophyll content and water relations due to greater accumulation of trace elements in tissues, with imbalances in nutrients uptake. Highly significant was the interaction between shoot elements concentration (Cd, Zn, Cu, Fe, Mg, K, Ca) and treatments. Heavy metals concentrations in roots always exceeded those in stem and leaves, with a lower translocation from roots to shoots, suggesting a strategy of sunflower to compartmentalise the potentially toxic elements in physiologically less active parts in order to preserve younger tissues.