Hyperaccumulation of nickel by two Alyssum species from the serpentine soils of Iran

Serpentine soils, which contain relatively high concentrations of nickel and some other metals, are the preferred substrate for some plants, especially those that accumulate Ni in their tissues. In temperate regions more Ni-hyperaccumulator plants are found in Alyssum than in any other genus. In this study, serpentine soils of two areas (Marivan and Dizaj) in the west/northwest of Iran and also perennial Alyssum plants growing on these soils were analyzed for Ni and some other metals. The highest concentrations of total metals in the soils of these areas for Ni, Cr, Co and Mn were 1,350, 265, 94 and 1,150 μg g⁻¹, respectively, while concentrations of Fe, Mg and Ca reached 3.55%, 16.8% and 0.585% respectively. The concentration of exchangeable Ni in these soils is up to 4.5 μg g⁻¹. In this study two Alyssum species, A. inflatum and A. longistylum, have been collected from Marivan and Dizaj, respectively. Analysis of leaf dry matter shows that they can contain up to 3,700 and 8,100 μg Ni g⁻¹, respectively. This is the first time that such high Ni concentrations have been found in these species. The concentrations of other metals determined in these species were in the normal range for serpentine plants, except for Ca, which was higher, up to 5.3% and 3.5%, respectively     

The effect of different iron concentrations on lead accumulation in hydroponically grown <Emphasis Type="Italic">Matthiola flavida</Emphasis> Boiss

The general relationship between heavy metals and mineral nutrition of plants grown in polluted environments is one of the most important factors for modifying the toxic properties of these metals. To study the effect of iron and lead pollution on the growth of Matthiola flavida a factorial research was undertaken in the form of a completely randomized design with four replications in hydroponic culture. After germination, seedlings were transferred to a hydroponic culture. During the pre-treatment step, a series of plants contained enough iron (+Fe), whereas the second series was without iron (?Fe). After the pre-treatment step, both series of plants were treated with three levels of iron as FeEDDHA and two levels of lead as Pb(NO₃)₂. The results showed that in both series of plants, lead reduced the root growth, shoot height, shoot and root dry weight. For 5 µM lead concentration, with increasing concentration of iron in the nutrient solution, concentration of lead in the roots and shoots decreased. For 1 µM concentration of lead, increasing the iron concentration in the nutrient solution reduced the concentration of lead in the roots, but had no significant effect on the amount of lead in shoots. Lead accumulation in shoots and roots of plants with Fe was more than plants without Fe. Also, in low concentrations of iron, the amount of iron in shoot increased with the increase of lead concentration in the nutrient solution. The results showed that in lead pollution, iron has a positive effect on investigated traits.     

Differential Changes in D1 Protein Content and Quantum Yield of Wild and Cultivated Barley Genotypes Caused by Moderate and Severe Drought Stress in Relation to Oxidative Stress

Plant Molecular Biology Reporter - The aim of this study was to investigate the effects of drought stress on oxidative damage and efficiency of PSII photochemistry in barley and compare the...     

Design and Synthesis of Selective Acetylcholinesterase Inhibitors: Arylisoxazole‐Phenylpiperazine Derivatives

In this work, a novel series of arylisoxazole‐phenylpiperazines were designed, synthesized, and evaluated toward acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Our results revealed that [5‐(2‐chlorophenyl)‐1,2‐oxazol‐3‐yl](4‐phenylpiperazin‐1‐yl)methanone ( 5c ) was the most potent AChE inhibitor with IC₅₀ of 21.85 μm . It should be noted that most of synthesized compounds showed no BChE inhibitory activity and [5‐(2‐fluorophenyl)‐1,2‐oxazol‐3‐yl](4‐phenylpiperazin‐1‐yl)methanone ( 5a ) was the most active anti‐BChE derivative (IC₅₀=51.66 μm ). Also, kinetic studies for the AChE and BChE inhibitory activity of compounds 5c and 5a confirmed that they have simultaneously bound to the catalytic site (CS) and peripheral anionic site (PAS) of both AChE and BChE. Furthermore, docking study of compound 5c showed desired interactions of that compound with amino acid residues located in the active and peripheral anionic sites. Compound 5c was also evaluated for its BACE1 inhibitory activity and demonstrated IC₅₀=76.78 μm . Finally, neuroprotectivity of compound 5c on Aβ‐treated neurotoxicity in PC12 cells depicted low activity.     

Lead, zinc and cadmium accumulation from two metalliferous soils with contrasting calcium contents in heavy metal-hyperaccumulating and non-hyperaccumulating metallophytes: a comparative study

Aims and background

We previously compared metallicolous (M) and non-metallicolous (NM) populations of Noccaea (=Thlaspi) caerulescens, Silene vulgaris, and Matthiola flavida for their abilities to tolerate and (hyper)-accumulate lead (Pb) in hydroponics. In the present study we aimed 1) to check the hyperaccumulation and tolerance abilities of these populations in controlled experiments using metalliferous soils, 2) to test the M. flavida M population for Zn and Cd hypertolerance in hydroponics.

Methods

Plants were grown in hydroponics and fertilized metalliferous substrates, collected from a Zn/Pb smelter sinter deposit near Plombières, Belgium (low pH, low Ca), and a tailing of the Irankouh Zn/Pb mine, Iran (high pH, high Ca). Metal tolerance was assessed from root growth inhibition in hydroponics, or mortality, stunting or chlorosis in the experiments with soil.

Results

Metallicolous M. flavida did not show hypertolerance or hyperaccumulation of Cd or Zn in hydroponics. Only one of the N. caerulescens M populations and the native S. vulgaris M population were able to grow in Plombières soil, whereas the others stopped growing or died within 40?days. All the populations survived and maintained growth for 40?days in Irankouh soil. When grown in Irankouh soil, the M population of M. flavida hyperaccumulated Pb. N. caerulescens hyperaccumulated Zn from Plombières soil, but not from Irankouh soil.

Conclusions

The M. flavida M population is non-Pb-hypertolerant. It hyperaccumulates Pb from Irankouh soil, but not from Pb-amended nutrient solution. N. caerulescens does not hyperaccumulate Zn from the calcareous Irankouh soil.