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Acta Biologica Hungarica
Authors: Elena Truta, Gabriela Vochita, Craita Rosu, Maria-Magdalena Zamfirache, and Zenovia Olteanu

The study was performed in order to evaluate Roundup-induced genotoxic effects in Hordeum vulgare L. cv. Madalin root meristems and to analyze herbicide impact on length growth of barley seedlings. Caryopses were treated for 3 hours and 6 hours with 0.1%, 0.5%, 1.0% and 2.0% Roundup solutions (v/v), containing 0.36 mg ml−1, 1.8 mg ml−1, 3.6 mg ml−1 and 7.2 mg ml−1 glyphosate active ingredient. Mitotic index decreased in both exposure times with concentration increase. In 3-h treatment, its average values decreased from 4.73 ± 0.31% to 1.51 ± 0.43%, whereas in 6-h treatment this parameter declined from 3.86 ± 0.92% to 0.62 ± 0.15%. The highest ana-telophase aberration rates were noted in 3-h treatments (8.91%, 9.19%, 9.47%, 11.25%, comparatively to control — 5.99%). Roundup enhanced the number of metaphase disturbances proving its noxious effect on normal functioning of mitotic spindle. Seedling growth was negatively influenced at all tested concentrations in both exposure times. The length decreased as concentration increased, so that the average length is 7.5–9 times smaller than in control at the maximum concentration, in both exposures.

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Sweet sorghum (Sorghum bicolor L. Moench cv. Róna) is a widely grown sugar crop that is used for bioenergy production. Since sorghum shows increased sensitivity to nutrient deficiency, the objective of this study was to reach an appropriate Cu level in plant tissues using various concentrations of Cu and ethylenediaminetetraacetic acid (EDTA) in order to enhance the photosynthetic activity and biomass production of plants. Copper accumulation increased in the root and stem of plants irrigated for 12 weeks with 0.1 μM CuCl2 both in the presence and absence of 300 μM EDTA and as a consequence, the plant-available Cu concentration in the soil extracts was lower at harvest. Although the copper content of leaves slightly increased, the transport of Fe and Mn, the microelements participating in light reactions of photosynthesis was negatively affected. In spite of this, 0.1 μM CuCl2 alone and with 200 or 300 μM EDTA enhanced the maximal CO2 assimilation rate (Amax) as a function of photon flux density (PPFD) and increased soluble sugar content in all plant parts. The dry mass of plants especially that of stems increased very significantly after 0.1 μM CuCl2 + 300 μM EDTA treatment. These results show that non-toxic concentration of copper in combination with suitable concentration of EDTA can enhance photosynthesis, biomass production, sugar content and the total copper accumulation in the shoot of sweet sorghum plants.

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The effect of copper excess on growth, H 2 O 2 level and peroxidase activities were studied in maize shoots. Ten-day-old seedlings were cultured in nutrient solution that contained Cu 2+ ions at various concentrations (50 and 100 μM) for seven days. High concentrations of Cu 2+ ions caused significant decrease both in matter production and elongation of maize shoots. In addition, treatment with CuSO 4 increased levels of H 2 O 2 and induced changes in several peroxidase activities. Moreover, the disturbance of the physiological parameters was accompanied by the modulation of the peroxidase activities: GPX (Guaiacol peroxidase, EC 1.11.1.7), CAPX (Coniferyl alcohol peroxidase, EC 1.11.1.4) and APX (Ascorbate peroxidase, EC.1.11.1.11). Furthermore, this modulation becomes highly significant, especially, in the presence of 100 μM of CuSO 4 .

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The objective of this study was designed to investigate the effect of seed priming with different concentrations of growth bioregulators ( i.e. indole acetic acid, gibberellic acid or kinetin) on growth and water relations of Vigna sinensis plants throughout various stages of plant growth and development.In the majority of cases, indole acetic acid, gibberellic acid or kinetin at different concentrations stimulated the growth vigour of cowpea plants (root length, root fresh and dry weight, shoot length, shoot fresh and dry weights and leaf area production) all over the growth periods.Seed pretreatment with IAA or kinetin induced significant increases in total leaf conductance and transpiration rate that was accompanied by a decrease in RWC. On the other hand, GA 3 induced reverse situation in these parameters.

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In the present study, the cytogenetic effects of the herbicide Avenoxan on meiotic chromosomes of Allium cepa and its relation with pollen sterility were studied. The bulbs with roots of Allium cepa were treated with a series of concentrations (0.1%, 0.2%, 0.4%) for 3, 6, 12 and 24 h. Controls and treated plants were shown to obtain M1 generation. All the used concentrations of the herbicide Avenoxan and exposure periods caused distinct increase in the number of abnormal cells when compared with the control. The type of the abnormalities induced: chromosome stickiness, bridges, laggards, univalents, quadrivalents and micronuclei. Avenoxan also caused pollen sterility. Increase of chromosomal aberrations was accompained by increase in pollen sterility.

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Galectin-1 (Gal-1), a mammalian lectin induces apoptosis of T lymphocytes. Contradictory data have resulted in confusing knowledge regarding mechanism of Gal-1 induced T-cell apoptosis. In this paper we aimed to resolve this controversy by comparing cell death induced by low (1.8 μM, lowGal-1) and high (18 μM, highGal-1) concentration of soluble Gal-1. We show that lowGal-1 and highGal-1 trigger phosphatidylserine exposure, generation of rafts and mitochondrial membrane depolarization. In contrast, lowGal-1 but not highGal-1 is dependent on the presence of p56lck and ZAP70 and activates caspase cascade. The results allow the conclusion that the cell-death mechanism strictly depends on the concentration of Gal-1.

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Acta Biologica Hungarica
Authors: Huan Zhang, Pan Wang, Ai-Jun Zhang, Xuan Li, Ji-Hong Zhang, Qi-Lian Qin, and Yi-Jun Wu

The housefly is an important resource insect and the housefly larvae are ideal source of food additives. The housefly larvae protein hydrolysates were obtained by enzymatic hydrolysis by alcalase and neutral proteinase. Their antioxidant activities were investigated, including the superoxide and hydroxyl radicalscavenging activity, 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity, reducing power and metal chelating activity. The antioxidant activities of both hydrolysates increased with their increasing concentrations. The alcalase hydrolysate (AH) showed higher scavenging activities against hydroxyl radical and superoxide anion radical at low concentrations and higher metal-chelating activity than the neutral proteinase hydrolysate (NPH). The NPH exhibited higher scavenging activity against DPPH free radical and higher reducing power than the AH. Both hydrolysates showed more than 50% superoxide anion radical-scavenging activity at 10 μg/mL. These results indicate that both housefly larvae protein hydrolysates display high antioxidant activities and they could serve as potential natural antioxidant food additives.

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Acta Biologica Hungarica
Authors: Tanja Pfeiffer, Ivna Štolfa, M. Žanić, N. Pavičić, Vera Cesar, and H. Lepeduš

Olive is one of the most important cultivated Mediterranean plants. In order to determine the differences in frost resistance of two, two-year-old olive cultivars (Olea europaea cv. Leccino and cv. Oblica) growing on different types of nutrient substrates (soil and coconut fibres), the trees were exposed to low temperature (−5 °C) in the dark. It was shown that low temperature caused an increase in H2O2 concentration, level of lipid peroxidation and carbonyl protein content in both cultivars and on both nutrient substrates, respectively. The CAT and APX activities significantly varied depending on the cultivar, the nutrient substrate type and the time of exposure to low temperature. Cv. Oblica and cv. Leccino growing on coconut fibres showed a better antioxidative response to low temperature probably due to the higher nitrogen and phosphorus concentration established in this type of nutrient substrate. That positive antioxidative response determined on coconut fibres was more pronounced in leaves of cv. Leccino.

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The renal- and hepato-toxicity induced by abamectin pesticide (Vertimec) and a commercial form of a bio-insecticide Bacillus thuringiensis (Agerin) in male albino rats were evaluated. Blood picture and blood glucose level were investigated. Male albino rats were administered dietary doses each equivalent to 1/10 or 1/100 of the LD 50 values of each toxicant for 30 consecutive days. Abamectin was found to pose risks of renal- and hepato-toxicity in rats, since the biochemical parameters of liver function (i.e. aspartate aminotransferase activity, alanine aminotransferase activity, acid phosphatase activity, albumin, and total protein levels) and kidney function (uric acid and creatinine concentration) were severely affected. These effects were verified by histopathological examination of liver and kidney tissues. Likewise, some haematological indices (i.e. erythrocyte count, leukocyte count and haemoglobin concentration) were also influenced; in addition abamectin might cause hypoglycaemia. On the other hand, the abovementioned lesions were less pronounced in the case of Bacillus thuringiensis -treated rats.

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Acta Biologica Hungarica
Authors: Márta Kotormán, Alexandra Varga, Phanindra Babu Kasi, and János Nemcsók

During the study of inhibition of amyloid fibril formation, α-chymotrypsin protein was developed in 55% ethanol at pH 7.0. We investigated the inhibitory effect of different spices on amyloid fibril formation using turbidity measurements and Congo red binding assays. We found that all spices except the black pepper and caraway seed prevented fibril formation. The highest inhibition was measured with the clove, which reduced the amount of aggregates by 90%. We studied the inhibitory effect of the cloves at different concentrations on aggregation, it was found that the inhibitory activity of clove is dependent on concentration. We have measured the total phenolic content of the spice extracts too. Based on all these findings we have come to the following conclusion: Our results indicate that spices can contain other compounds too – not only phenolic compounds – which influence the formation of amyloid fibrils, and the effectiveness of various phenolic compounds are different.

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