Impact of Aries River Contaminants on Algae and Plants.

The Aries River (Western Romania) represents one of the most important affluents of the Mures River, with great significance in the Mures Tisza basin. The environmental quality of the Aries basin is significantly affected by both historic mining activities and contemporary impacts. Thus, an evaluation of the effects of the main contaminants found in water (organochlorine pesticides-OCPs, monocyclic aromatic hydrocarbons-MAHs, polycyclic aromatic hydrocarbons-PAHs, and metals) on cyanobacteria and plants was performed. Among OCPs, hexachlorocyclohexane isomers, dichlorodiphenyltrichloroethane, and derivatives were detected in plants while admissible concentrations were detected in water. Among MAHs, high levels of benzene were detected both in water and in plants. The levels of PAHs exceeded the allowable values in all samples. Increased concentrations of metals in water were found only at Baia de Aries, but in plants, all metal concentrations were high. The pH, nitrates, nitrites, and phosphates, as well as metals, pesticides, and aromatic hydrocarbons, influenced the physiological characteristics of algae, test plants, and aquatic plants exposed to various compounds dissolved in water. Considering that the Aries River basin is the site of intense past mining activities, these data provide information about the impact on water quality as a consequence of pollution events.

Structure and surface dynamics of genomic DNA as probed with surface-enhanced Raman spectroscopy: Trace level sensing of nucleic acids extracted from plants.

In this work surface-enhanced Raman spectra of nucleic acids from in vitro grown Solanum tuberosum L. cultivars and populations (Buzau population, Lazarea population, Patraque d'Auvergne, RFA Roclas Clone 2.6 Ferma, Vitelotte Negresse, Roclas Clone C, Blue Congo) were measured with 532 nm laser line. Main surface-enhanced Raman modes of these DNAs have been analyzed. Also, DNA from two grapevine (Vitis vinifera L.) varieties were studied at acidic pHs by surface-enhanced Raman spectroscopy. Modified SERS intensities and wavenumber shifts of nucleic acids bands were observed upon lowering the pH, being a proof of binding affinity changes of DNA with silver nanoparticles (AgNPs) and of structural modifications induced at acidic pHs in DNA molecular groups. Furthermore, the (sub)picosecond surface dynamics of DNA extracted from leaf tissues of grapevine (Vitis vinifera L.) varieties was investigated. In this work, the bands full widths at half-maximum (FWHMs) have values in the wavenumber range from 8 to 34 cm-1. (Sub)picosecond molecular dynamics of DNA groups with global relaxation times between 0.31 ps - 1.33 ps has been found.

Cryo-Technologies for Ex Situ Conservation of Rosa Germplasm.

In this study, we compare two rapid cryopreservation (-196 °C) procedures, droplet-vitrification and encapsulation-dehydration for rose (Rosa × hybrida L., cultivars 'Ioana', 'Mariana', 'Vulcan'). Significant factors for cryopreservation, such as sucrose concentration during osmoprotection, treatment duration with plant vitrification solution 2 (PVS2) in droplet-vitrification, duration of air desiccation and moisture content of alginate beads in encapsulation-dehydration, were investigated. In addition, the morphogenetic response to in vitro culture and to liquid nitrogen storage and the content in photosynthetic pigments have been assessed. The in vitro cultures were initiated from plant material originating from field collection. The highest regeneration frequencies were obtained for cv. 'Vulcan' in both of the cryopreservation procedures tested, 72% in droplet-vitrification and 65% following encapsulation-dehydration. The morphogenetic response (multiplication index and height of shoots) to liquid nitrogen storage was direct multiple shoot formation per initial shoot tip for all genotypes. The content in chlorophyll a and b was statistically comparable in plant material resulting from cryopreserved and non-cryopreserved shoot tips in all cultivars. The findings expand the information on Rosa's response to in vitro culture conditions and cryopreservation, providing protocols with a high regeneration capacity for the storage of genotypes with high ornamental value.

Simultaneous determination of glucose, fructose, sucrose and sorbitol in the leaf and fruit peel of different apple cultivars by the HPLC-RI optimized method.

A high performance liquid chromatography method with refractive index detection (HPLC-RI), for simultaneous determination of glucose, fructose, sucrose and sorbitol in leaf and/or apple peel samples from nine apple (Malus domestica Borkh.) cultivars and rootstocks, originating from a germplasm collection, has been developed and validated. Box-Behnken design of response surface methodology was applied for the method optimization. The Carbosep Coregel 87H3 column was used under the optimum conditions predicted: mobile phase of H2SO4 0.005 mol L(-1) solution, flow rate of 0.3 mL min(-1) and column temperature of 35°C. The method was validated for linearity (R(2)>0.99), limits of detection (2.67-4.83 µg mL(-1)) and quantification (8.9-16.1 µg mL(-1)), precision (%RSD<5.05) and recovery (93.94-103.06%) and satisfactory results obtained. The sugars content varied across micropropagated plants in vitro, plants regenerated after cryostorage, growing trees in vivo, and fruit peel.

Structural Changes Induced in Grapevine (Vitis vinifera L.) DNA by Femtosecond IR Laser Pulses: A Surface-Enhanced Raman Spectroscopic Study.

In this work, surface-enhanced Raman spectra of ten genomic DNAs extracted from leaf tissues of different grapevine (Vitis vinifera L.) varieties, respectively, are analyzed in the wavenumber range 300-1800 cm-1. Furthermore, structural changes induced in grapevine genomic nucleic acids upon femtosecond (170 fs) infrared (IR) laser pulse irradiation (λ = 1100 nm) are discussed in detail for seven genomic DNAs, respectively. Surface-enhanced Raman spectroscopy (SERS) signatures, vibrational band assignments and structural characterization of genomic DNAs are reported for each case. As a general observation, the wavenumber range between 1500 and 1660 cm-1 of the spectra seems to be modified upon laser treatment. This finding could reflect changes in the base-stacking interactions in DNA. Spectral shifts are mainly attributed to purines (dA, dG) and deoxyribose. Pyrimidine residues seem to be less affected by IR femtosecond laser pulse irradiation. Furthermore, changes in the conformational properties of nucleic acid segments are observed after laser treatment. We have found that DNA isolated from Feteasca Neagra grapevine leaf tissues is the most structurally-responsive system to the femtosecond IR laser irradiation process. In addition, using unbiased computational resources by means of principal component analysis (PCA), eight different grapevine varieties were discriminated.

Surface-enhanced Raman spectroscopy of genomic DNA from in vitro grown tomato (Lycopersicon esculentum Mill.) cultivars before and after plant cryopreservation.

In this work the surface-enhanced Raman scattering (SERS) spectra of five genomic DNAs from non-cryopreserved control tomato plants (Lycopersicon esculentum Mill. cultivars Siriana, Darsirius, Kristin, Pontica and Capriciu) respectively, have been analyzed in the wavenumber range 400-1800 cm(-1). Structural changes induced in genomic DNAs upon cryopreservation were discussed in detail for four of the above mentioned tomato cultivars. The surface-enhanced Raman vibrational modes for each of these cases, spectroscopic band assignments and structural interpretations of genomic DNAs are reported. We have found, that DNA isolated from Siriana cultivar leaf tissues suffers the weakest structural changes upon cryogenic storage of tomato shoot apices. On the contrary, genomic DNA extracted from Pontica cultivar is the most responsive system to cryopreservation process. Particularly, both C2'-endo-anti and C3'-endo-anti conformations have been detected. As a general observation, the wavenumber range 1511-1652 cm(-1), being due to dA, dG and dT residues seems to be influenced by cryopreservation process. These changes could reflect unstacking of DNA bases. However, not significant structural changes of genomic DNAs from Siriana, Darsirius and Kristin have been found upon cryopreservation process of tomato cultivars. Based on this work, specific plant DNA-ligand interactions or accurate local structure of DNA in the proximity of a metallic surface, might be further investigated using surface-enhanced Raman spectroscopy.