chlorophyll-a and sodium-sulfate

Prosopis strombulifera (Lam.) Benth. is a halophytic shrub found in highly saline soils in Argentina, with high tolerance against NaCl but strong growth inhibition by Na

Topics: Anions; Argentina; Calcium; Chlorophyll; Cytochrome b Group; Magnesium; Osmosis; Phosphorus; Photosynthesis; Photosystem II Protein Complex; Plant Leaves; Plant Proteins; Plant Roots; Plant Shoots; Potassium; Prosopis; Protein Binding; Salinity; Sodium; Sodium Chloride; Sulfates

Chromium (Cr) contamination of soil and water has become a severe threat to human health. In this study, a series of experiments were conducted to examine the ameliorative effects of Cr toxicity, by exogenous 100 μM sodium sulfate. Our team has examined the plant growth, Cr content, chlorophyll, antioxidant index and soluble protein content, before and after the addition of sodium sulfate. The results showed that the addition of sulfur (S) can reduce the enrichment of Cr and the content of malonyldialdehyde (MDA) under Cr stress. After addition of S in the culture solution, the biomass and roots length of Arabidopsis thaliana increased under Cr stress. Furthermore, the content of chlorophyll, superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), glutathione (GSH), and soluble protein increased with the addition of sulfur. Transmission electron microscope observation point to that the chloroplasts can be damaged in leaf. All data demonstrate that S supplementation should help to alleviate the negative effects caused by both Cr(III) and Cr(VI) on Arabidopsis thaliana.

Topics: Antioxidants; Arabidopsis; Chlorophyll; Chromium; Malondialdehyde; Models, Theoretical; Oxidative Stress; Soil Pollutants; Sulfates

The study of the microalgal growth kinetics is an indispensable tool in all fields of phycology. Knowing the optimal nutrient concentration is an important issue that will help to develop efficient growth systems for these microorganisms. Although nitrogen and phosphorus are well studied for this purpose, sulfur seems to be less investigated. Sulfate is a primary sulfur source used by microalgae; moreover, the concentration of this compound is increasing in freshwater systems due to pollution. The aim of this study was to investigate the effects of different sodium sulfate concentrations in the culture medium on growth and growth kinetics of the freshwater microalga Chlamydomonas moewusii. Production of biomass, chl content, kinetic equations, and a mathematical model that describe the microalgal growth in relation with the concentration of sodium sulfate were obtained. The lowest concentration of sodium sulfate allowing optimal growth was 0.1 mM. Concentrations higher than 3 mM generated a toxic effect. This work demonstrates that this toxic effect was not directly due to the excess of sulfate ion but by the elevation of the ionic strength. An inhibition model was successfully used to simulate the relationship between specific growth rate and sodium sulfate in this microalga.

Topics: Aquaculture; Chlamydomonas; Chlorophyll; Culture Media; Fresh Water; Kinetics; Microalgae; Models, Biological; Osmolar Concentration; Sulfates

The effects of simulated acid rain (SAR) on the ultrastructure and functional parameters of the photosynthetic apparatus were studied using 14-day-old pea leaves as test system. Pea plants were sprayed with an aqueous solution containing NaNO₃(0.2 mM) and Na₂SO₄(0.2 mM) (pH 5.6, a control variant), or with the same solution, which was acidified to pH 2.5 (acid variant). Functional characteristics were determined by chlorophyll fluorescence analysis. Acid rain application caused reduction in the efficiency of the photosynthetic electron transport by 25%, which was accompanied by an increase by 85% in the quantum yield of thermal dissipation of excess light quanta. Ultrastructural changes in chloroplast were registered by transmission electron microscopy (TEM) after two days of the SAR-treatment of pea leaves. In this case, the changes in the structure of grana, heterogeneity of thylakoids packaging in granum, namely, the increase of intra-thylakoid gaps and thickness of granal thylakoids compared to the control were found. The migration of protein complexes in thylakoid membranes of chloroplasts isolated from leaves treated with SAR was suppressed. It was shown also that carbonic anhydrase activity was inhibited in chloroplast preparations isolated from SAR-treated pea leaves. We proposed a hypothesis on the possible inactivation of thylakoid carbonic anhydrase under SAR and its involvement in the inhibition of photochemical activity of chloroplasts. The data obtained allows to suggest that acid rains negatively affect the photosynthetic apparatus disrupting the membrane system of chloroplast.

Topics: Acid Rain; Carbonic Anhydrases; Chlorophyll; Electron Transport; Hydrogen-Ion Concentration; Light; Microscopy, Electron, Transmission; Nitrates; Photosynthesis; Pisum sativum; Plant Leaves; Plant Proteins; Protein Transport; Sulfates; Thylakoids

Experiments were conducted to study the effects of different sodium salts viz., sodium chloride (NaCl), sodium sulphate (Na(2)SO(4)) and sodium carbonate (Na(2)CO(3)) on growth, dry matter production, mineral contents, biochemical constituent and enzyme activities of sunflower (Helianthus annuus L.). The germinating sunflower seeds were treated with 10, 20 and 50mM NaCl and Na(2)SO(4) and 5, 10 and 15 mM Na(2)CO(3). The seedling growth, minerals, chlorophyll content and biochemicals like protein and free amino acid contents with enzyme activities like ATPase and protease were analysed on 8 DAS. The seedlings were separated into root, stem, leaf and cotyledon on 8 DAS. All the treatments decreased the germination percentage; shoot length, root length, leaf area and dry weight, chlorophyll and protein contents significantly. Potassium, sodium and free amino acid contents; activities of ATPase and protease were increased when compared to control. This effect was very high in the Na(2)CO(3) treated seedlings this was followed by Na(2)SO(4) and NaCl treated seedlings. From the results of this investigation, it is clear that, the sunflower seedlings were affected significantly in the Na(2)CO(3) treatments, and followed by Na(2)SO(4) and NaCl treatments.

Topics: Adenosine Triphosphatases; Carbonates; Carboxypeptidase B; Chlorophyll; Helianthus; Potassium; Sodium; Sodium Chloride; Sulfates

The value of intrinsic chlorophyll fluorescence polarization, and the intensity in emission spectrum were investigated in leaf segments of Alocasia macrorrhiza under several stress conditions including different temperatures (25-50 degrees C), various concentrations of NaCl (0-250 mM), methyl viologen (MV, 0-25 microM), SDS (0-1.0%) and NaHSO(3) (0-80 microM). Fluorescence emission spectrum of leaves at wavelength regions of 500-800 nm was monitored by excitation at 436 nm. The value of fluorescence polarization (P value), as result of energy transfer and mutual orientation between chlorophyll molecules, was determined by excitation at 436 nm and emission at 685 nm. The results showed that elevated temperature and concentrations of salt (NaCl), photooxidant (MV), surfactant (SDS) and simulated SO(2) (NaHSO(3)) treatments all induced a reduction of fluorescence polarization to various degrees. However, alteration of the fluorescence spectrum and emission intensity of F(685) and F(731) depended on the individual treatment. Increase in temperature and concentration of NaHSO(3) enhanced fluorescence intensity mainly at F(685), while an increase in MV concentration led to a decrease at both F(685) and F(731). On the contrary, NaCl and SDS did not cause remarkable change in fluorescence spectrum. Among different treatments, the negative correlation between polarization and fluorescence intensity was found with NaHSO(3) treatments only. We concluded that P value being measured with intrinsic chlorophyll fluorescence as probe in leaves is a susceptible indicator responding to changes in environmental conditions. The alteration of P value and fluorescence intensity might not always be shown a functional relation pattern. The possible reasons of differed response to various treatments were discussed.

Topics: Alocasia; Chlorophyll; Fluorescence Polarization; Hot Temperature; Oxidants, Photochemical; Paraquat; Plant Leaves; Sodium Chloride; Sodium Dodecyl Sulfate; Spectrometry, Fluorescence; Sulfates; Sulfur Dioxide; Surface-Active Agents