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Objective of this study was to evaluate effects of Pb and Zn on model crop Brassica napus L. (rapeseed). Plants were grown hydroponically in presence of various concentrations (25-1000 μmol/L) of Pb or Zn. Addition of studied metals into nutrient solution resulted in reduction of length, fresh as well as dry mass of rapeseed plant organs and the inhibitory effect increased with increasing external Pb or Zn concentration. Metal exposed plants showed significant decrease in the concentration of assimilation pigments (chlorophyll a, chlorophyll b, carotenoids) and soluble proteins, and increased accumulation of thiobarbituric acid reactive substances in leaves. Metal treatment was also connected with loss of water in shoots, which was greater for Pb exposed variants. Accumulation of studied metals into roots of rapeseed cultivar Verona showed gradual saturation with increasing Pb or Zn concentration in hydroponics. Lead concentration in shoot tissue was much lower than that of Zn. The effectiveness of metal translocation from root to shoot was pronounced much more for Zn treated plants. [ABSTRACT FROM AUTHOR]

The response of hydroponically cultivated rapeseed (Brassica napus L.; c.v. Verona) plants to Cd, Ni (6-120 μmol L-1) and Hg (6-60 μmol L-1') was investigated. Metal application resulted in reduced length as well as dry mass of rapeseed plant organs and the inhibitory effect increased with increasing metal concentration in external solution. Due to metal application significant decrease in the concentration of assimilation pigments (chlorophyll a, chlorophyll b, carotenoids) and proteins in rapeseed leaves was observed. At the highest applied concentration leaf protein content represented only 47.3 % (Cd), 60.9 % (Ni) and 56.4 % (Hg) of the control. On the other hand, concentration of thiobarbituric acid reactive substances (TBARS) rose with the increasing metal concentration. Due to treatment with 120 μmol L-1 Cd or Ni, TBARS content was 1.64 (Cd) and 2.28 (Ni) times higher than that of the control, while after application of 60 μmol L-1 Hg it was about 2.91 times higher. Metal treatment was also connected with loss of water content in shoot, which was the smallest at Ni application. Treatment with 120 μmol L-10 Ni resulted in 12.7 % loss of water in comparison to control plants while at application of the same Cd concentration loss of water reached 37%. In general, the highest toxicity was exhibited by Hg. Accumulated metal concentrations in roots of rapeseed cultivar Verona showed linear increase with increasing external Cd, Ni and Hg concentration. The lowest metal concentration in shoot tissue exhibited Hg. The effectiveness of metal translocation from root to shoot increased as follows: Hg < Cd

The response of hydroponically cultivated rapeseed (Brassica napus L.; c.v. Verona) plants to Cr(III)-nitrate was investigated. The applied metal concentration varied in the range from 6 to 480 μmol L-1 (i.e. 0.31212.480 mg L-1). Cr(III) application resulted in reduced length, fresh mass as well as dry mass of rapeseed plant organs and the inhibitory effect of Cr(III) increased with increasing metal con-centration in the external solution. The roots were more sensitive to Cr(III) treatment than the shoots. Due to Cr(III) application significant decrease in the concentration of assimilation pigments (chlorophyll a, chlorophyll b, carotenoids), proteins and reduced thiol groups in rapeseed leaves was observed. As an indicator of lipid peroxidation, malondialdehyde contents were used, expressed as thiobarbituric acid reactive substances (TBARS). The concentration of TBARS rose with the increasing Cr(III) concentration. Accumulated Cr concentration in roots of rapeseed cultivar Verona showed linear increase with increasing external Cr(III) concentration reaching 22810 mg Cr kg-1 at treatment with 480 μmol L-1 Cr(III), however translocation of Cr into the shoots was low, what was reflected in small values of translocation factors (0.0015-0.0330). [ABSTRACT FROM AUTHOR]

A series of twenty substituted 2-hydroxy-3-[(2-aryloxyethyl)amino]propyl 4-[(alkoxycarbonyl)amino]benzoates were prepared and characterized. As similar compounds have been described as potential antimycobacterials, primary in vitro screening of the synthesized carbamates was also performed against two mycobacterial species. 2-Hydroxy-3-[2-(2,6-dimethoxyphenoxy)ethylamino]-propyl 4-(butoxycarbonylamino)benzoate hydrochloride, 2-hydroxy-3-[2-(4-methoxyphenoxy)ethylamino]-propyl 4-(butoxycarbonylamino)benzoate hydrochloride, and 2-hydroxy-3-[2-(2-methoxyphenoxy)ethylamino]-propyl 4-(butoxycarbonylamino)benzoate hydrochloride showed higher activity against M. avium subsp. paratuberculosis and M. intracellulare than the standards ciprofloxacin, isoniazid, or pyrazinamide. Cytotoxicity assay of effective compounds was performed using the human monocytic leukaemia THP-1 cell line. Compounds with predicted amphiphilic properties were also tested for their effects on the rate of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. All butyl derivatives significantly stimulated the rate of PET, indicating that the compounds can induce conformational changes in thylakoid membranes resulting in an increase of their permeability and so causing uncoupling of phosphorylation from electron transport.