جستجوی مقالات مرتبط با کلیدواژه « nickel » در نشریات گروه « زیست شناسی »

Heavy metal contamination (HMs) of water and soil is the most serious problem caused by industrial and mining processes and other human activities. Mycoremediation is a biotechnological method that employs fungi to remove toxic contaminants from the environment in an efficient and cost-effective manner. Pleurotus species are considered to be the most popular and widely cultivated species worldwide, and this may be due to their low production cost and high yield. It has been indicated that Pleurotus species may improve plant growth in metal-contaminated soils through enhancing nutrition uptake or by alleviating toxicity of the metals. In this experiment, the fungus was grown in vitro in liquid and solid media for 3 weeks on five different concentrations (0, 15, 30, 45, 60 ppm) of five heavy metals (Cd, Zn, Ni, Pb, Mn) as sulphate and the effect of these metal on radial growth, biomass production and metal content of fungal biomass were determined. Based on the results, this fungus showed a great variety of tolerance against the metals, as that growth parameters were increased in the case of two metals contamination (Zn and Mn) and inhibition of growth was observed even at the low concentrations of nickel, cadmium and lead (15 mg/liter). The amount of metal accumulation in the fungal mycelium also increased with the increase of the metal concentration in the culture medium. In this research, for the first time, the growth parameters and the amount of accumulation of heavy metals in axenic conditions have been investigated and described.

Respiratory Burst Oxidase Homologue (RBOH) is involved in the perception and response to environmental stresses in plants by producing reactive oxygen molecules. In the present study, the expression of RBOH gene and morphophysiological parameters of Citrullus colocynthis in different concentrations of nickel chloride were investigated. 15-day-old seedlings were treated with different concentrations of nickel chloride (0, 150, 300 and 450 µM). The results showed that with increasing nickel chloride concentration, shoot and root length, shoot and root dry weight and relative water content decreased and the activity of superoxide dismutase and catalase, and content of proline, malondialdehyde and hydrogen peroxide increased significantly compared to the control group. Also, in treated plants, the uptake of elements such as manganese and zinc decreased. The expression level of RBOH gene also increased with increasing the amount of nickel chloride compared to untreated plants. According to the results of this study, nickel metal stress induces the expression of RBOH gene in C. colocynthis.

The toxicity of heavy metals such as copper and nickel induces oxidative stress in tomato cultivars, due to the production of free radicals and damage to the plasma membrane due to toxic amounts of copper and nickel. When the negative effects of oxidative stress exceed the ability of the antioxidant resistance system, the plant decreases its growth and yield. In this research, we tried to study the simultaneous effect of two histidine and malate ligands on growth improvement and oxidative stress reduction in two new tomato cultivars including Cal J N3 and Early urbana under simultaneous stresses of copper and nickel in standard hydroponic conditions. 9 post-optimization treatments containing concentrations of 150 and 300 μM of copper and nickel, 300 and 600 μM of histidine and 1 and 2 mM of malate were in the base of Hoagland solution. The treatments were applied to plants cultivated at 50 ml Falcon tube containing Hoagland solution without culture medium in three replications. After treatment, parameters such as morphological growth, total protein content, changes in the activity of catalase and peroxidase enzymes, H2O2 accumulation, Malon dialdehyde and so on were measured in both cultivars. The results showed that the simultaneous use of 600 μM and 2 mM from histidine and malate ligands had a significant effect on oxidative stress improvement on tomato cultivars under 300 μM of nickel and copper stresses. Thus, by adding ligands in stress conditions, oxidant indices improved in comparison with control, indicating a greater correlation between plasma membrane and reduced absorption and transport of nickel and copper free cations. In addition, Cal j N3 cultivar gave a more significant relative response to growth and oxidation parameters of ligands under stress conditions. Ligands seem to be confronted by the influence of heavy metals on physiological, molecular, enzymatic activity and nutrient substitution, which it is suggested to study the effect of ligands on the molecular level.

Plants grown in serpentine soils, in addition to heavy metals which their indicators is nickel (Ni) are encountered with a lot of edaphically stress such as drought stress. At the present study, we investigated the effect of pretreatment Ni and PEG-simulated drought stress on some physiological parameters and Ni accumulation of the serpintine plant, Cleome heratensis and related non-serpertine plant, Cleome foliolosa. After 75 days, half number of vessels with grown plants in hydroponic condition, received 20 µM Ni for 7 days, and then plants ± Ni were exposed to drought stress which simulated by PEG in three levels (0, -0.3, or −0.9MPa ) for 7 days. Results showed that serpentine plant populations were pretreated with Ni, shoot to root ratio significantly decreased and relative water content improved and these plants accumulate most of Ni in the root and with drought stress, accumulation Ni in the root increased and translocation it to shoot reduced, Serpentine plant in the highest level of water stress and total phenol amount was enhanced which agreement Phenyle alanin ammonia lyase (PAL) activity in the highest drought stress in C. heratensis, but deleterious effect on same parameters in C. foliolosa. Thus, it can be suggested that serpentine plants use nickel to increase drought resistance which represent the genotypic dependence of serpentine plants to nickel in order to improve drought stress resistance.

Heavy metals pollution, especially heavy metals, is one of the major environmental problems. These pollutants involve soil, water and related ecosystems and cause problems for the flora and even humans. Microalgae have many features, which make them ideal candidates for elimination of petroleum pollution and reduction of various heavy metals contaminations. This study was carried out using Calothrix sp., which isolated from polluted areas with the aim of investigating the reduction of nickel as well as studying some physiological behaviors of microalgae. Experiments design was done with the Design Expert software, which considered factors like PH (pH4-9), nickel concentration (5-100 mg/L) and time (30-120 min). The results showed that at pH8 with 80.74 mg/L nickel concentration and 48.24 min was observed the highest nickel uptake (69%). Treatment of algal biomass with different chemical and physical factors in various forms, such as immobilization or use of its metabolites could improve and facilitate the absorption process and create the potential for using these microalgae in subsequent purification systems.

Todays, secondary metabolites from microorganisms have been to improve food, pharmaceutical and chemical industries . Extremophile microorganisms are one of the resources for the secondary metabolites. The heavy metal resistant halotolerants were isolated from Haj AliGholi Khan Salt Lake. The potential of the isolates for producing secondary metabolites were molecularly investigated by amplification of nrpS genes with specific primers A3/A7 and NS1/NS2. In the screening of Haj AliGholi Khan Lake microorganisms; 13% of isolates from MGM, 19.5% from MH, 43.75% from SWN, 3.7% from LNSWN and 20.62% from normal Nutrient agar were obtained. The halotolerant were highly resistant against Ni and highly susceptible to Cd. Three to 7 PCR products were identified from optimized PCR reaction of nrpS genes of heavy metal resistant halotolerant with specific primers. Existence of nrpS genes among halotolerant and semi- halophile microorganisms from Haj AliGholi Khan Salt Lake revealed a direct relation between heavy metal resistance and genetic potential for producing secondary metabolites.

Aim and Bacteria types that live in the plants rhizosphere can improve the plants growth via taking advantage. In coexistence of leguminous plants with rhizobium bacteria, in addition to the fact that the main part of nitrogen is stabilized, the soil is also strengthened in terms of nitrogen. The purpose of this study was Three-Rhizobia Screening On the amount of photosynthetic pigments of The Cowpea (Vigna Unguiculata) Plant Which Was Under Nickel Stress. In this study, two standard samples of Rhizobium (PTCC 1654) (and (PTCC 1684) and strain isolated from the node were performed and PCR steps were performed on it and the strain as well as nickel was inoculated with clove bean plant. To do so, the samples in three bacterial concentrations, namely 1.5 × 106 CFU/ml, 1.5 × 107 CFU/ml and 1.5 × 108 CFU/ml, and nickel in three concentrations of 200, 400 and 600 µM were inoculated. The samples were studied after ten days. The experiment was implemented in a factorial manner within the format of a completely randomized plot in three iterations. At the end of the period, the amount of the photosynthesis pigments was statistically analyzed by making use of SPSS software ver.19. Generally. The results showed that the concentration of inoculant strains isolated from node 1.5 × 107 CFU/ml and 200 mM nickel increased photosynthetic pigments (chlorophyll a, chlorophyll b, chlorophyll) in the plant.
Discussion and Finally, it can be concluded that the use of growth promoting bacteria isolated from nodules on plant biochemistry of photosynthetic pigments cowpea (Vigna unguiculata) nickel was effective stress.

Nickel is an essential microelement for plant growth, but upper levels of this element serve as heavy metal which create toxic effects on plants and human. Application of mineral nutrition is a useful strategy for overcoming of this serious problem. In order to investigate the effects silicon nutrition on growth and physiology indices of basil (Ocimum basilicum L.) under nickel stress condition a factorial experiment based on completely randomized design with four replication was conducted in Research Greenhouse of Mohaghegh Ardabili University at 2014-2015. Experimental factors included nickel stress(0, 75, 100 and 150 ppm) and foliar spraying of plants with 1Mm concentration of silicon and control (spraying with water). During this experiment traits such as plant height, plant dry weight, root and stem dry weight, leaf and stem number, leaf area, chlorophyll index, electrolyte leakage, relative water contents, photosynthetic pigments and antioxidant enzymes and nickel accumulation in root and aerial part of plants were measured. Results indicated that the effect of nickel stress on all of traits were significant. At 150 ppm concentration of nickel, vegetative growth criteria and biochemical characteristic of basil plants reduced significantly. Foliar spraying of silicon could be alleviated the unfavorable effects of nickel stress via increases in chlorophyll b, carotenoid and carbohydrate content of leaves and increases in catalase enzyme activity also reduction in nickel content in aerial part of plants.

Serpentine soils are dry and contain rather high levels of nickel (Ni).To obtain a better understanding of drought tolerance by Ni in serpentine plants, a hydroponic trial was designed to compare the effects of Ni on growth factors, Ni uptake or translocation and some physiological parameters in the serpentine plant, Fortuynia garcinii (Burm.f.), under PEG simulated drought stress (3 levels). After 45 days, half number of vessels received 10 µM Ni for 8 days, and then plants ± Ni were exposed to drought stress for 8 days. The result indicating Ni treatment improved only slightly RWC, and Ni accumulation of root was consistently higher than shoot. The main reason for this action related to low translocation factors for this metal that showing this plant was more tolerant to plant-internal Ni. Photosynthetic pigments increased under drought stress treatments, but the treatments with Ni were consistently lower in compare same treatments without Ni in this serpentine plant. Phenolic compounds, water soluble carbohydrate, Glycine betaine and proline were also increased by Ni application under PEG simulated drought stress indicating that Ni improved the osmotic adjustment ability and enhance the antioxidant capacity. It is hypothesized that Ni could improve the drought tolerance of the serpentine plant by enhancing water utilization capability, osmotic adjustment and the abilities of antioxidative defense.

Halophile and halotolerant microorganisms produce bio-active molecules under environmental stresses. The microorganisms play a role in bio-remediation of heavy metals including nickel; the most important water pollutant in urbans. Here studying of nickel resistant microorganisms from salt lake of Haj Ali Gholi Khan for their potential in bio-active molecules producing based on PKS genes variations is aimed. Chemical analyses using atomic absorption method for soil and water of the lake were done. The microorganisms isolated from MGM, MH and SWN culture media with 23, 10 and 2 % salt. The isolates were screened for nickel resistant’s followed by analyzing for presence of PKS genes using gene specific internal primers. Fifty, 22 and 21 microorganisms were isolated from SWN, MH and MGM medium respectively. 65% of the isolates were nickel resistant those carry the potential to synthesize bio-active compounds. These organisms because of their abilities in bio- remediation and also synthesizing bio molecules can be used in biotechnology.

Heavy metals contamination of soil is a widespread global problem. One approach to reduce the accumulation of heavy metals in plants is using of different growing substrates. In order to investigate of different combinations substrate and heavy metals effect on physiological and biochemical traits in bean) cv. Sadri), an experiment was conducted. The first factor included four salt of heavy metals Cd(NO3)2, Pb(NO3)2, Ni(NO3)2 and CuSO4) with 50 mg kg-1 soil concentration and a control surface without metal and the second factor included of four levels of different growing substrates (control (farm soil), compost, vermicompost and poplar sawdust). The results showed that the heavy metals reduced the rate of photosynthesis and increased ion leakage, proline, soluble sugar and MDA compared to control. Use of vermicompost by developing the physical and chemical of soil statuse caused to increase chlorophyll content, instantaneous water use efficiency, stomatal conductance, photosynthesis rate and soluble sugar and also reduced the electrolyte leakage of pinto bean leaves. As a result, it could play a positive role to reduce the effects of heavy metal stress on plant physiological and biochemical traits of pinto bean.

Aim and Studies demonstrated that some ligands such as maltol in coordination with metals, induce apoptosis and inhibit the cancer cells proliferation. The aim of this study is the synthesis of new complexes of nickel and evaluation of anti-proliferative and apoptotic effects of these compounds.
Material and In this study, we synthesized the novel complexes of nickel with maltol, deferiprone and 3-hydroxyflavone ligands. The cytotoxicity of this complex was screened for antitumor activity against HeLa, MCF-7, MDA-MB-231, NALM-6, Neuro-2a and L929 by MTT assay and Flow cytometry.
The IC50 ± SD (μM) values, calculated for synthesized complex against HeLa, MCF-7, MDA-MB-231, NALM-6, Neuro-2a and L929 cell lines are between 15.6 to 199.1, 5.00 to 185.2 and 39.8 to 168.8 for complexes 1 to 3 respectively.
Our results showed that investigated complex exhibited higher cytotoxic activities against MDA-MB-231 and Neuro-2a compared to other cell lines. Our results confirmed that the synthesized compound have not any cytotoxicity effects on mouse fibroblast cell line (L929).

Aim and For a long time the interactions of microorganisms has been the subject of studies, and the achievements has been exploited for different usages such as: control or removal of heavy metals from wastewaters. To serve such importance the measurement of resistance of various bacteries to different heavy metals is essential.
Thus this study is oriented to assess the effects of heavy metals such as cadmium and nickel on Pseudomonas aeruginosa (extracted from wastewaters of Tehran) and exposure of encoding and resistant genes to the subject heavy metals which are similar to czr, is studied.
Material and In this study 240 specimens were collected from sewers and wastewaters of which only 10% Pseudomonas aeruginosa were extracted and purified, and thereafter the resistance of this bacterium against different densities of salt of cadmium and nickel through MIC measurement were measured and studied. Nevertheless PCR was used for the detection of encoding resistant to Cadmium (another heavy metal) gene.
The studies revealed that Pseudomonas aeruginosa Bacteria (extracted from wastewaters of Tehran) was totally immune to 1 µM of Nickel, but it was resistant to Cadmium in a range from 9.6µM to 79µM. also the existence of resistant gene to Cadmium (czr) in this Bacteria was proved via PCR.
The results showed that subject Bacteria was resistant to Cadmium, but the threshold of its resistant is dependent on the amount of heavy metal in its environment.

In plants, there are complex network of transport, chelation, and sequestration processes that functions in maintaining concentrations of essential metal ions in different cellular compartments, thus minimizing the damage caused by entry of non-essential metal ions into the cytosol. In the presence of toxic ones, arbuscular mycorrhizal (AM) fungi are able to alleviate metal toxicity in the plant. In this study the effect of an arbuscular mycorrhizal fungi Funneliformis intraradices on growth, Nickel tolerance, and ABC transporter and metallothionein expression in leaves and roots of tall fescue (Festuca arundinacea) plants cultivated in Ni polluted soil were evaluated. The fungi infected (M) and uninfected (M-) fescue plants were cultivated in soil under different Ni concentrations (0, 30, 90 and 180 ppm) for 3 months. Results demonstrated the positive effect of fungi colonization on the increase in growth and reduction in Ni uptake (90 and 180 ppm) and Ni translocation from roots to shoot of tall fescue under Ni stress. The results also demonstrated that the level of ABC transporterand metallothionein transcripts accumulation in roots was considerably higher for both M- and M plants compared to the control. Also, M plants showed less ABC and MET expression compared to the M- plants. These results demonstrated the importance of mycorrhizal colonization of F. intraradices in reduction of Ni transport from root to shoot of tall fescue which alleviates Ni-induced stress.

Freshwater rotifer B. calyciflorus is one of the major zooplanktic species that is important in aquaculture, aquatic ecosystem foodchain and environmental monitoring. nickel is one of the stable environmental contaminants since it cannot be chemically degraded or destroyd. In present study, population response of rotifer B. calyciflorus to six different concentrations of nickel (0.025, 0.05, 0.1, 0.2, and 0.4 mg/l) with three replicates per concentration was studied for 8 days. Rotifer density and specific growth rate were calculated daily in the control and treatments containing nickel . Result showed that, rotifer population growth decreased significantly (p

Lolium perenne has symbiosis relationships with an important group of endophytes; genus Neotyphodium. Agronomic traits of this plant and its resistance to biotic and abiotic stresses are affected by Neotyphodium spp.، resulting to changes in its physiology and morphology. Effect of Nickel and endophyte symbiosis on growth parameters and nickel uptake in two different natural populations are investigated in this study. Each population consisted of two groups of plant (E+ and E-; with or without endophyte). Treatments consisted of 0، 30، 90 and 180 mg Ni kg 1- soil)، and growth parameters including root and shoot wet، dry weight and length، tiller number، and nickel uptake in root and shoot were evaluated after 3 months from treatment. After 3 months from treated plants، significant decrease in root and shoot biomass of E+ and E- plants was observed in 180 treatment and endophyte infection decreased the biomass plants. However، endophyte infection significantly improved the tillering ability of host ryegrass. Also، a significant increase in the Ni concentration of root and shoot was observed under Ni stress and the Ni concentration of E+ plants was 12. 7% and 88. 7% higher in root and shoot، respectively، than in E- plants. Results indicated decreases in root and shoot wet and dry weights were decreased in concentration 180 mg. kg-1 treatments، and root length in concentration 30 mg. kg-1. Greatest number of tillers observed in population 1 in 30 mg. kg-1 treatment. Nickel uptake was significantly increased in roots and shoots of both populations when soil Ni was increased. Nickel uptake of root and shoot in two populations of L. perenne plants was decreases in presence of with endophytes (E+ plants) which is considered as an important factor towards decrease in negative effects of this element. Population 1 with more shoot tiller and nickel uptake under stress conditions could be introduced as the suitable population to be cultivated in stress conditions.

Toxic metal pollution is effluents from hospitals and factories. Remove them from the environment is important. Iranian Research Organization for Science and Technology of yeast Saccharomyces carlsbergensis PTCC 5051, and received as a lyophilized culture YEDPA environment and then the proliferation of malt extract broth is used. In this study, the effects of parameters such as pH, temperature, kinetics and adsorption isotherm nickel and zinc were determined by Saccharomyces. Maximum amount of nickel and zinc uptake in the pH range 5/5, and 6 was respectively. Kinetic studies showed that the biological uptake of nickel by biomass on Saccharomyces was quickly removed and most of the first test was done in less than 30 minutes. Adsorption of nickel and zinc were determined by Saccharomyces active and in active. Uptake by yeast is more active. Nickel and zinc uptake by Saccharomyces inactivated by autoclaving or sodium azide and di-nitro phenol has been investigated. Maximum amount of nickel and zinc absorption were 0.65 and 0.47 mmol g. Remove toxic heavy metals from wastewater by the yeast Saccharomyces hospitals is high performance.

Tropical plant، Catharanthus roseus contains worthy alkaloids such as vinblastine and ajmalicine. Since amount and pattern of alkaloid production could be affected by different environmental conditions، the effect of two elements of cadmium and nickel were investigated. Plants in the greenhouse conditions using a chemically inert substrate were cultivated and in a complete randomized block design were treated by different concentrations of cadmium and nickel until appearance of toxicity symptoms. The concentrations of cadmium and nickel، chlorophyll and total alkaloids of the leaves were measured. The patterns of alkaloids were determined by thin layer chromatography using of UV light and specific reagents of ceric ammonium sulfate and dragendorff. The results showed that toxicity symptoms of cadmium occurred at 10 µM or more and 50 µM or more for nickel which was accompanied with a decrease in chlorophyllconcentration and intervein chlorosis. By increase the concentration of metals، both the concentrations of metals and alkaloids increased in leaves but the concentrations of alkaloids decreased at very high concentration of cadmium. The chromatographic pattern of alkaloids was changed too. Treatment by cadmium and nickel caused appearance or intensified the bands of alkaloids with medium RF such as vincolidine or low RF such as serpentine. Indeed، cadmium and nickel by increase of the ample alkaloids، increase of the accumulation of rare alkaloids and increase in the ratio of alkaloid content to biomass، caused an increase to the total alkaloids.