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1.
Cultures ofStreptomyces tendae andPenicillium expansum grown on Actinomyces and Czapek's media, respectively, were exposed to 5 mg L–1 of manganese, magnesium, iron, cobalt, nickel, copper and zinc, supplied as sulfate salts. Only copper markedly increased geosmin (1, 10-dimethyl-9-decalol), biomass, and spore production. inductively coupled plasma-atomic emission spectrometric analysis ofS. tendae andP. expansum cells did not indicate an accumulation of copper. Both 1 and 5 mg L–1 copper, as copper sulfate, increased total geosmin production in cultures ofS. tendae on several media, but decreased production on others, suggesting that substrate composition affects responses to copper.  相似文献   

2.
The microalga Haematococcus lacustris is a source of astaxanthin used widely in aquaculture, pharmaceutical, and cosmetic industries. A new strain of Haematococcus (LCR‐26C‐1f) isolated from the New Zealand alpine zone was evaluated in this study. The influence of vitamins, micronutrients, various carbon and nitrogen sources were investigated to maximize biomass production in batch cultures using shake flasks. Supplementation of vitamins consisting of thiamine, biotin, and cyanocobalamin improved the cell density by 40% over the vitamin‐free medium. Out of the individual vitamins tested, thiamine was shown to be necessary to maintain high cell densities. The best nitrogen source tested was nitrate in the form of sodium nitrate, at a 40 mM concentration. Heterotrophic growth yielded much lower cell densities compared to autotrophic growth. The micronutrients iron and manganese were essential for growth. However, the best growth was obtained using a micronutrient mix that included iron, copper, cobalt, zinc, manganese and molybdenum.  相似文献   

3.
Summary In a greenhouse study, inoculation with the mycorrhizal fungusGlomus fasciculatum enhanced peanut growth and increased its dry matter more than 2-fold compared with the non-inoculated control, in both sterilized and non-sterilized soil. It also significantly increased uptake of phosphorus and micronutrients such as zinc, copper, manganese and iron.Present address: International Crops Research Institute for the semi-arid tropics (ICRIAST), Patancheru 502 324, A.P. India.  相似文献   

4.
The aim of this research was to investigate the capability of Brassica napus to bioaccumulate zinc and copper from artificially contaminated soil at the flowering and maturation phenological stage. The trial was set up in a greenhouse and the plants were cultivated in pots. The agricultural soil utilized was contaminated with zinc and copper sulfate (300 and 600 mg/kg, respectively). The soil and plant samples were simultaneously collected during the flowering (8 weeks after seeding) and maturation (harvest time, 13 weeks after seeding) stages, and the heavy metal concentrations were then analyzed. The production of vegetable biomass and the length of the roots were measured. The results showed that B. napus accumulated zinc and copper and translocated these elements in different ways in the harvestable parts of the plants. The zinc bioaccumulation was higher than that of copper. At flowering, zinc was mainly accumulated in the shoots (stems + leaves). Copper was particularly accumulated in the roots, during the entire life cycle. Taking into account the biomass production, the highest heavy metal removal by the shoots (above‐ground parts) occurred at the flowering stage for both zinc and copper. The high bioavailability of zinc and copper in the soil did not severely affect the root length and the biomass production.  相似文献   

5.
Summary The effects of a fritted micronutrient mixture on the growth and yield of tomatoes were studied in relation to the pH of the peat substrate. The treatments consisted of three rates of application of the fritted micronutrient mixture (0, 200, 500 g/m3 F 253A) in factorial combination with four rates of liming (average pH values 4.5, 5.1, 5.8 and 6.7). Three crops were grown to maturity, and in each case the total yield of fruit decreased (18–24%) when the peat was limed to pH>6.0 (P<0.001). Omission of the micronutrient mixture reduced the yield by 20–65% (P<0.001). The combination of heavy liming and omission of micronutrients was particularly detrimental, and depressed the yield by 40–87% as compared with the most favourable treatment. The incidence of ripening disorders was also increased by heavy liming and by omission of micronutrients. The boron, copper, iron, manganese and zinc contents of the leaves are tabulated. Multiple regression analyses suggested that the yield was consistently depressed by deficiencies of boron and copper, and responses to iron and manganese were also found.  相似文献   

6.
Transitions in the growth limiting factor from light (I) to nitrogen (N) and vice versa caused changes in geosmin production, protein and carbohydrate content, and the synthesis of pigments such as chlorophyll a (Chl a), phycobiliproteins (PBPs), and -carotene of the cyanobacterium Oscillatoria brevis. Following IN transition the first 150h, the decrease in protein content was compensated for by an increase of carbohydrates, and thereby, a constant biomass level was maintained in this period. Thereafter, biimass dropped to 15% of its initial level. A decrease in geosmin and pigment content was observed during transition from IN-limited growth. However, geosmin increased relative to phytol (Chl a) and -carotene which may indicate that a lowered demand for phytol and -carotene during N-limited growth allows isoprenoid precursors to be directed to geosmin rather than to pigment synthesis. Synthesis of Chl a and -carotene at the expense of geosmin was suggested for the observed start of increase in geosmin production only at the time that Chl a and -carotene had reached their I-limited steady state. Transition from nitrogen to light limited growth caused an acceleration of metabolism shown by a rapid decrease in carbohydrate content accompanied by an increase in protein content. The growth rate of the organisms temporarily exceeded the dilution rate of the culture and the biomass level increased 6-fold. Due to the only modest changes in geosmin production (2-fold) compared to changes in biomass level (6-fold) during I-or N-limited growth, environmental factors seem to have limited effect on geosmin production.Abbreviations Chl a chlorophyll a - dry wt dry weight; - I-limited light-limited - N-limited nitrogen-limited - PBP phycobiliprotein This research was performed at the Department of Microbiology, University of Amsterdam, with finacial support provided by the Royal Norwegian Ministry of Foreign Affairs and the Royal Norwegian Council for Scientific and Industrial Research  相似文献   

7.
Mineral nutrient malnutrition, and particularly deficiency in zinc and iron, afflicts over 3 billion people worldwide. Wild emmer wheat, Triticum turgidum ssp. dicoccoides, genepool harbors a rich allelic repertoire for mineral nutrients in the grain. The genetic and physiological basis of grain protein, micronutrients (zinc, iron, copper and manganese) and macronutrients (calcium, magnesium, potassium, phosphorus and sulfur) concentration was studied in tetraploid wheat population of 152 recombinant inbred lines (RILs), derived from a cross between durum wheat (cv. Langdon) and wild emmer (accession G18-16). Wide genetic variation was found among the RILs for all grain minerals, with considerable transgressive effect. A total of 82 QTLs were mapped for 10 minerals with LOD score range of 3.2–16.7. Most QTLs were in favor of the wild allele (50 QTLs). Fourteen pairs of QTLs for the same trait were mapped to seemingly homoeologous positions, reflecting synteny between the A and B genomes. Significant positive correlation was found between grain protein concentration (GPC), Zn, Fe and Cu, which was supported by significant overlap between the respective QTLs, suggesting common physiological and/or genetic factors controlling the concentrations of these mineral nutrients. Few genomic regions (chromosomes 2A, 5A, 6B and 7A) were found to harbor clusters of QTLs for GPC and other nutrients. These identified QTLs may facilitate the use of wild alleles for improving grain nutritional quality of elite wheat cultivars, especially in terms of protein, Zn and Fe.  相似文献   

8.
The present study on efficacy of different Glomus species, an arbuscular mycorrhizal (AM) fungus (G. aggregatum, G. fasciculatum, G. mosseae, G. intraradices) on various growth parameters such as biomass, macro and micronutrients, chlorophyll, protein, cytokinin and alkaloid content and phosphatase activity of pink flowered Catharanthus roseus plants showed that all Glomus species except G. intraradices enhanced the chlorophyll, protein, crude alkaloid, phosphorus, sulphur, manganese and copper contents of C. roseus plants along with phosphatase activity significantly over uninoculated plants. However only G. mosseae and G. fasciculatum exhibited superior symbiotic relationship with the plant. G. mosseae was found to be the best for increasing the crude alkaloid content (8.19%) in leaf and also in increasing the quantity of important alkaloids vincristine and vinblastine.  相似文献   

9.
A greenhouse experiment was designed to investigate the correlations between waterlogging and aeration, and associated changes in pH, redox potentials and sulfide concentrations, on the growth of Spartina alterniflora Loisel. Elemental concentrations of the aerial and root material were determined and used for correlations with growth response. Redox potentials adjusted to pH 7 (Eh 7) ranged from −184 mv to 5 mv and were highly correlated (r) with aerial and root dry weight biomass (.97 and .97, respectively) and plant height (1.0). The range of soil pH at the conclusion of the study was 6.07 to 6.74 and was negatively correlated with aerial and root dry weight biomass. Sulfide concentrations ranged from 10–2 to 10–7 m and vorrelations with aerial and root dry weights and height were −.85, −.85 and −.87, respectively. High negative correlations were found between sodium and sulfur concentrations and S. alterniflora growth. Positive correlations between potassium, phosphorus, manganese, zinc, copper, iron and growth response were also observed. Correlations of elemental concentrations of the plants with redox potentials and/or pH suggest that these two physical variables may be responsible in part for the regulation of 5. alterniflora growth in nature by regulating availability of nutritional elements.  相似文献   

10.
The toxic milk (tx) mouse is a rodent model for Wilson disease, an inherited disorder of copper overload. Here we assessed the effect of copper accumulation in the tx mouse on zinc and iron metabolism. Copper, zinc and iron concentrations were determined in the liver, kidney, spleen and brain of control and copper-loaded animals by atomic absorption spectroscopy. Copper concentration increased dramatically in the liver, and was also significantly higher in the spleen, kidney and brain of control tx mice in the first few months of life compared with normal DL mice. Hepatic zinc was increased with age in the tx mouse, but zinc concentrations in the other organs were normal. Liver and kidney iron concentrations were significantly lower at birth in tx mice, but increased quickly to be comparable with control mice by 2 months of age. Iron concentration in the spleen was significantly higher in tx mice, but was lower in 5 day old tx pups. Copper-loading studies showed that normal DL mice ingesting 300 mg/l copper in their diet for 3 months maintained normal liver, kidney and brain copper, zinc and iron levels. Copper-loading of tx mice did not increase the already high liver copper concentrations, but spleen and brain copper concentrations were increased. Despite a significant elevation of copper in the brain of the copper-loaded tx mice no behavioural changes were observed. The livers of copper-loaded tx mice had a lower zinc concentration than control tx mice, whilst the kidney had double the concentration of iron suggesting that there was increased erythrocyte hemolysis in the copper-loaded mutants.  相似文献   

11.
The aim of this study was to determine the effects of oral zinc treatment on red cell copper/zinc-superoxide dismutase (Cu/Zn-SOD) activity and zinc and copper concentrations in growth retardation. Thirty-five patients, average age of 11 yr, were selected. The control group consisted of 10 healthy children whose average age was 10 yr. Superoxide dismutase activity was determined by spectrophotometer. Copper and zinc concentrations were measured by an atomic absorption spectrophotometer. The activity of Cu/Zn-SOD before zinc treatment was higher than the controls (p<0.001). There was a decrease in Cu/Zn-SOD activity after zinc treatment (p<0.001) and the values after treatment were still higher than the controls (p<0.001). Plasma zinc concentrations before zinc treatment were lower than controls (p<0.01). After treatment, there was an increase in plasma zinc concentrations compared to controls and the patients' values before zinc treatment, respectively (p<0.001, p<0.001). After zinc treatment, plasma copper concentrations were decreased significantly (p<0.01). An increase in red cell zinc concentration (p<0.01) and a decrease in copper concentration (p<0.001), which were statistically significant, were seen after zinc treatment. The results suggested that there were significant alterations in Cu/Zn-SOD activity and zinc and copper concentrations during growth retardation. With zinc treatment, these parameters appeared to approach normal values.  相似文献   

12.
Ninety-six crossbred growing pigs were used to evaluate the effects of fluoride levels on growth performance, nutrient digestibility, and the retention of minerals in tissues. Four dietary treatments were formulated by supplementing fluorine (as NaF) to a corn-soybean basal diet (39.75 mg/kg F) to provide the following added fluorine levels: 0, 50 100, and 150 mg/kg fluorine. The results showed pigs of the 100 and 150 mg/kg fluorine-added groups had decreased average daily gain (ADG) and increased feed gain ratio (F/G) compared to the control (p<0.05). Apparent digestibility of protein and calcium in 100 and 150 mg/kg fluorinetreated groups was significantly lower than that of the control (p<0.05). On the other hand, iron, copper, zinc, and manganese levels in most tissues of the 100 and 150 mg/kg fluorine groups were markedly changed compared to the control (p<0.05). However, growth performance, nutrient digestibility, and mineral concentrations in all tissues of pigs were not significantly affected by the addition of 50 mg/kg fluorine (p>0.05). Thus, this study suggested that excess fluoride levels could decrease growth performance and change the retention of iron, copper, zinc, and manganese in pigs.  相似文献   

13.
Nutrient addition experiments conducted during the ice-free seasons of 1983 and 1984 in Gem Lake, an alpine lake in the Sierra Nevada mountains of California, indicate that algal biomass is limited by phosphorus, in combination with iron or copper. Phosphorus additions were always required to stimulate growth, but did not do so when phosphorus was the only nutrient added. Simultaneous additions of phosphorus and iron resulted in increased levels of chlorophyll, particulate carbon, particulate nitrogen and particulate phosphorus. Simultaneous additions of phosphorus and copper resulted in increases in chlorophyll, particulate nitrogen and particulate phosphorus, not in particulate carbon. Neither iron nor copper by itself stimulated growth.Particulate N : P ratios from all seasons in Gem Lake suggest that simultaneous micronutrient and phosphorus limitation exists throughout the summer, when nutrient and biomass levels remain low; limitation by phosphorus alone may appear in the fall and spring, when biomass and major ion concentrations increase dramatically.  相似文献   

14.
The aims of this study were to determine the effect of breast milk zinc, copper, and iron concentrations on infants’ growth and their possible correlations with maternal dietary intake. Milk samples and information on food intake were collected from 182 lactating women. Concentrations of zinc, copper, and iron in milk were analyzed using atomic absorption spectrophotometry. The infant’s weight for age Z-score (WAZ) and height for age Z-score (HAZ) were calculated. The mean milk zinc, copper, and iron concentrations were 1.85?±?0.5, 0.53?±?0.3, and 0.85?±?0.2 mg/l, respectively. Only zinc mean level was lower than the recommended range. Association between zinc, copper, and iron concentrations of milk and WAZ or HAZ of infants were not significant. However, the WAZ of infants whose mothers' milk zinc was more than 2 mg/l was significantly (P?<?0.039) higher than for others. The mean dietary zinc (5.31?±?2.3 mg/day) and copper (1.16?±?0.7 mg/day) intake of mothers was significantly less than the required daily intake (RDA) recommendations (P?<?0.05). The mean dietary iron intake (11.8?±?8.2 mg/day) was significantly higher than RDA recommendation (P?<?0.001). No significant association was found between maternal mean dietary zinc, copper, and iron intakes with their concentrations in milk. Dietary consultation or/and zinc supplementation is suggested for lactating women and infants.  相似文献   

15.
Pregnant women in developing countries are vulnerable to multiple micronutrient deficiencies. Studies assessing serum levels of the micronutrients and magnitude of their deficiencies are very scarce in African subjects. This study was aimed at determining serum levels of micronutrients in 375 pregnant (42 HIV seropositive) and 76 non-pregnant women (20 HIV seropositive) who visited the University of Gondar Hospital, Gondar, Ethiopia. Serum concentrations of zinc,\ copper, selenium, calcium, and magnesium were determined using an inductively coupled plasma mass spectrometer. Irrespective of HIV serostatus, pregnant women had significantly higher serum concentrations of copper and copper/zinc ratio and significantly lower magnesium compared to those in non-pregnant women (P < 0.05). Except for selenium, which was significantly lower in HIV-seropositive pregnant women (P < 0.05), the mean serum concentrations of zinc, copper, calcium, and magnesium were not significantly different between pregnant women by HIV serostatus. The prevalence of deficiency in zinc, magnesium, selenium, and calcium in the pregnant women, irrespective of their HIV serostatus, was 66.7%, 25.6%, 21.9%, and 9.3%, respectively. The magnitude of deficiency in zinc, magnesium, and selenium was significantly higher in HIV seropositive pregnant women (76.2%, 52.4%, and 45.2%) than that in HIV-seronegative pregnant women (65.5%, 22.2%, and 18.9%) and in HIV-seronegative non-pregnant women (42.9%, 8.1%, and 30.4%; P < 0.05). Deficiency in one, two, three, or four mineral elements was observed in 44.8%, 14.4%, 9.9%, and 5.1% of the pregnant women, respectively. Only 25.9% of the pregnant women and 44.7% of the non-pregnant women were not deficient in any of the micronutrients. The high prevalence of micronutrient deficiencies in pregnant and non-pregnant women in Gondar, Ethiopia warrants the need for strategies on prevention and control of the deficiencies.  相似文献   

16.
Iron, copper, and zinc are key micronutrients that play an important role in the immune response to Mycobacterium tuberculosis. The present study aimed to evaluate the association between serum levels of those micronutrients, inflammatory markers, and the smear and culture conversion of M. tuberculosis during 60 days of tuberculosis treatment. Seventy-five male patients with pulmonary tuberculosis (mean age, 40.0?±?10.7 years) were evaluated at baseline and again at 30 and 60 days of tuberculosis treatment. Serum levels of iron, copper, zinc, albumin, globulin, C-reactive protein, and hemoglobin, and smear and cultures for M. tuberculosis in sputum samples were analyzed. Compared to healthy subjects, at baseline, patients with PTB had lower serum iron levels, higher copper levels and copper/zinc ratio, and similar zinc levels. During the tuberculosis treatment, no significant changes in the serum levels of iron, zinc, and copper/zinc were observed. Lower serum copper levels were associated with bacteriological conversion in tuberculosis treatment (tuberculosis-negative) at 30 days but not at 60 days (tuberculosis-positive). C-reactive protein levels and the C-reactive protein/albumin ratio were lower in tuberculosis-negative patients than in tuberculosis-positive patients at 30 and 60 days after treatment. Albumin and hemoglobin levels and the albumin/globulin ratio in patients with pulmonary tuberculosis increased during the study period, regardless of the bacteriological results. High serum globulin levels did not change among pulmonary tuberculosis patients during the study. Serum copper levels and the C-reactive protein/albumin ratio may be important parameters to evaluate the persistence of non-conversion after 60 days of tuberculosis treatment, and they may serve as predictors for relapse after successful treatment.  相似文献   

17.
L Song  JG Qin  S Su  J Xu  S Clarke  Y Shan 《PloS one》2012,7(7):e41459
The requirements of micronutrients for biomass and hydrocarbon production in Botryococcus braunii UTEX 572 were studied using response surface methodology. The concentrations of four micronutrients (iron, manganese, molybdenum, and nickel) were manipulated to achieve the best performance of B. braunii in laboratory conditions. The responses of algal biomass and hydrocarbon to the concentration variations of the four micronutrients were estimated by a second order quadratic regression model. Genetic algorithm calculations showed that the optimal level of micronutrients for algal biomass were 0.266 μM iron, 0.707 μM manganese, 0.624 μM molybdenum and 3.38 μM nickel. The maximum hydrocarbon content could be achieved when the culture media contained 10.43 μM iron, 6.53 μM manganese, 0.012 μM molybdenum and 1.73 μM nickel. The validation through an independent test in a photobioreactor suggests that the modified media with optimised concentrations of trace elements can increase algal biomass by 34.5% and hydrocarbon by 27.4%. This study indicates that micronutrients play significant roles in regulating algal growth and hydrocarbon production, and the response surface methodology can be used to optimise the composition of culture medium in algal culture.  相似文献   

18.
In order to investigate the dependence of growth rate upon plant concentrations of iron, manganese and zinc, Betula pendula seedlings were cultivated in a hydroponic system. In three different experiments, all essential nutrient elements except iron, manganese or zinc, were titrated in non-growth limiting amounts at low external concentrations. The solution was continuously recirculated and sprayed on the roots. The micronutrients (Fe, Mn and Zn) were added as addition rates, RA (day-1), relative to the calculated internal amount in the plants. No chelates were added to the culture solution.At steady-state nutrition, plant relative growth rate showed a linear dependence upon the internal concentration of the limiting micronutrient. These data do not support the Steenbjerg effect where negative correlations between growth and plant nutrient concentrations have been reported. Steady-state nutrition was associated with very different growth responses to the different limiting nutrients.  相似文献   

19.
Residual nutrients from Murashige and Skoog medium were analyzed following a 5-wk multifactor experiment. Plant density, sugar concentration, and plant growth regulators (benzyladenine and ancymidol) were examined using four genotypes of daylily (Hemerocallis) to determine which factors most influenced nutrient use. Active nutrient uptake was observed for 11 nutrients (potassium, sodium, copper, phosphorus, iron, calcium, magnesium, manganese, boron, sulfur, and zinc) with lower concentrations in spent medium than in the tissue water volume (fresh-dry mass expressed as mL H2O). Two patterns of nutrient use were visualized by correlative analysis of nutrient uptake. Greatest growth lowered plant nutrient concentrations of potassium, sodium, phosphorus, iron, and copper in all genotypes, and luxuriant uptake was indicated with least growth. Potassium, sodium, iron, and copper concentrations in plant dry matter were equal to or exceeded what is observed in vigorously growing nursery plants. However, phosphorus concentration in plant dry matter was low enough to be considered deficient when compared to Hemerocallis plants in nursery production. With a second group of nutrients (calcium, magnesium, manganese, and boron), the genotype, “Barbara Mitchell” lacked active uptake and was deficient. Calcium concentration was low in all plants compared to Hemerocallis grown under nursery conditions (“Barbara Mitchell” was the lowest concentration) despite active uptake by the other three genotypes—“Brocaded Gown,” “Mary’s Gold,” and “Heart of a Missionary.” Magnesium concentration in these three genotypes was low enough in vessels with greatest growth to question its adequacy at high densities. Increased sucrose in medium reduced the dry matter concentrations of all tested nutrients. Plant growth regulators had less impact on nutrient use than genotype and plant density. Nutrient uptake may be an important physiological component of genotypic variation.  相似文献   

20.
The serum concentrations of copper, zinc, iron, and cobalt and copper/zinc ratio were investigated in horses infected with equine herpesvirus-1 (EHV-1). Nine horses were naturally infected with the virus and nine healthy horses served as controls. The concentrations of copper, zinc, iron, and cobalt were determined spectrophotometrically in the blood serum of all horses. The results were (expressed in micrograms per deciliters) copper 2.80 ± 0.34 vs 1.12 ± 0.44, zinc 3.05 ± 0.18 vs 0.83 ± 0.06, iron 2.76 ± 0.17 vs 3.71 ± 0.69, cobalt 0.19 ± 0.37 vs 0.22 ± 0.45, and copper/zinc ratio 0.72 ± 0.38 vs 1.41 ± 0.36 for control vs infected group, respectively. In conclusion, copper and zinc concentrations of the infected group were lower than the control group (p < 0.001), whereas iron concentration and the copper/zinc ratio of the infected group were higher than the control group (p < 0.05 and p < 0.001). The cobalt concentration was not found to be statistically different between two groups. It might be emphasized that copper/zinc ratio was significantly affected by the EHV-1 infection, so it could be taken into consideration during the course of infection. An erratum to this article can be found at  相似文献   

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