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The objective of the present work was to study the phytoremediation capacity of Callitriche cophocarpa concerning water contaminated with thallium (Tl), cadmium (Cd), zinc (Zn), and lead (Pb) derived from the natural environment. We found that after a 10-day incubation period, shoots of C. cophocarpa effectively biofiltrated the water so that it met (for Cd, Zn, and Pb) appropriate quality standards. The order of accumulation of the investigated elements by shoots (mg kg(-1) dry weight) were as follows: Zn (1120) < Tl (251) < Cd (71) < Pb (35). The order of bioconcentration factors were as follows: Cd (1177) < Tl (1043) < Zn (718) < Pb (597). According to Microtox bioassay, C. cophocarpa significantly eradicated polluted water toxicity. During the experiment, the physiological status of plants was monitored by taking measurements of photosystem II activity (maximum efficiency of PSII, photochemical fluorescence quenching, nonphotochemical fluorescence quenching, and quantum efficiency of PSII), photosynthetic pigment contents, and shoot morphology. Plants exposed to metallic pollution did not exhibit significant changes in their physiological status compared with the control. This work is potentially applicable to the future use of C. cophocarpa in the phytoremediation of polluted, natural watercourses.

The aim of the present study was to investigate the binding strength of chromium (Cr) ions to aquatic macrophyte Callitriche cophocarpa. Shoots of the plants were incubated in a natural water solution containing Cr(III) or Cr(VI) at a concentration ranging from 0.5 to 4 mM under laboratory conditions. We found that C. cophocarpa has an extremely high capacity to bind Cr. The average level of accumulation reached 28,385 or 7,315 mg kg−1 dry weight for plants incubated with Cr(III) or Cr(VI), respectively. Shoots incubated in a 0.5 mM concentration of Cr(III) for 5 days removed almost 100 % of the metal from solution. The major pool of the bound Cr(III) ions follows the strongest mechanism of metal-binding to an organic matter. In contrast, we found that only 25 % of Cr(VI) ions are bound into the metallo-organic compounds and 57 % of Cr(VI) exists in an easily remobilizable form. Activity of a photosynthetic electron transport (as FV/FM) was evaluated with respect to the Cr-binding mechanism. Our results contribute to the development of knowledge on processes controlling bioremediation of heavy-metallic compounds in aquatic systems.

Fruits of several, mainly Polish cultivars of floricane-and primocane-fruiting red raspberry (Rubus idaeus), black raspberry (Rubus occidentalis) and blackberry (Rubus fruticosus), grown in central Europe during two successive vegetation periods, were investigated. The content of phenolic compounds, including anthocyanins, as well as antioxidant properties of fruit extracts were analysed. A number of methods were employed: ferric ion reducing antioxidant power (FRAP), cupric ion reducing antioxidant capacity (CUPRAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity involving both colorimetric and EPR spectrometric measurements. From among all the tested fruits black raspberries had the largest antioxidant capacity as verified by all methods used in this study. These berries were also the most abundant in phenolic and anthocyanin compounds. Blackberries were characterised by larger antioxidant capacity than red raspberry fruits which were accompanied by higher content of total phenolics and anthocyanins. Berries of primocane-fruiting cultivars, often used for intensive agricultural production, generally did not differ in the total phenolic and anthocyanin content as well as in the antioxidant capacity as compared to the traditional, floricane-fruiting ones. The research contributes to deep characterisation of central European berry fruits which due to their high content and large diversity of health-beneficial compounds are classified as natural functional food.

The movements of chloroplasts in response to varying levels and wavelengths of incident light were investigated in leaves of four fern species: Adiantum capillus-veneris, Adiantum caudatum, Adiantum diaphanum and Pteris cretica. In all of the species studied blue light induced chloroplast redistribution resulting in face and profile patterns that were typical of low and high fluence rates, respectively. Fluence rate response characteristics and the kinetics of transmission changes accompanying these blue-lightinduced movements were similar to those observed in the leaves of higher plants. Only in A. capillus-veneris was the distribution of chloroplasts affected by red light. The response was of the weak-light type, irrespective of the light intensity. The most effective fluence rate for red light was found to be below 7·2 m mmol m -2 s -1 (1 W m -2 ). The effect of red light was far-red reversible, indicating phytochrome involvement. Chloroplast responses were more dynamic in A. capillus-veneris and P. cretica, the two species that exhibited higher environmental flexibility.