Plant senescence and proteolysis: two processes with one destiny

Abstract Senescence-associated proteolysis in plants is a complex and controlled process, essential for mobilization of nutrients from old or stressed tissues, mainly leaves, to growing or sink organs. Protein breakdown in senescing leaves involves many plastidial and nuclear proteases, regulators, different subcellular locations and dynamic protein traffic to ensure the complete transformation of proteins of high molecular weight into transportable and useful hydrolysed products. Protease activities are strictly regulated by specific inhibitors and through the activation of zymogens to develop their proteolytic activity at the right place and at the proper time. All these events associated with senescence have deep effects on the relocation of nutrients and as a consequence, on grain quality and crop yield. Thus, it can be considered that nutrient recycling is the common destiny of two processes, plant senescence and, proteolysis. This review article covers the most recent findings about leaf senescence features mediated by abiotic and biotic stresses as well as the participants and steps required in this physiological process, paying special attention to C1A cysteine proteases, their specific inhibitors, known as cystatins, and their potential targets, particularly the chloroplastic proteins as source for nitrogen recycling

Wine analysis by 1D and 2D NMR spectroscopy

We have measured 1D and 2D $^1$H and $^{13}$C NMR spectra of selected Slovenian wines. Partial assignment of $^1$H and $^{13}$C resonances of alanine, valine, leucine, isoleucine, proline, threonine, ethanol, glycerol, butyleneglycol, and of acetic, tartaric, lactic, succinic, and malic acids in the wine samples was carried out by the combination of homo- and heteronuclear experiments COSY, HSQC and HMBC with known spectra of individual compounds. The spectra of wines of different variety, vintage and geographical areas differ mainly in the intensity of particular signals but also in the appearance of some signals which offers the possibility to follow the variability in their chemical composition on the ground of $^1$H and $^{13}$C signals

The application of NMR and MS methods for detection of adulteration of wine, fruit juices, and olive oil. A review

This review covers two important techniques, high resolution nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS), used to characterize food products and detect possible adulteration of wine, fruit juices, and olive oil, all important products of the Mediterranean Basin. Emphasis is placed on the complementary use of SNIF-NMR (site-specific natural isotopic fractionation nuclear magnetic resonance) and IRMS (isotope-ratio mass spectrometry) in association with chemometric methods for detecting the adulteration

Analysis of uncertainties caused by the atmospheric dispersion model in accident consequence assessments with UFOMOD

SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Uncertainty analyses for the atmospheric dispersion submodule of UFOMOD with emphasis on parameter correlations

SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Detection of Honey Adulteration by Sugar Syrups Using One-dimensional and two-dimensional High-resolution Nuclear Magnetic Resonance

The importance of honey adulteration detection has recently increased owing to the limited production levels in recent years and to the relative high price of honey, therefore this illegal practice has becoming more and more attractive to producers. Hence the need has arisen for more effective analitical methods aiming at detecting honey adulteration. The present research presents an effective method to detect adulteration in honey falsified by intentional addition of different concentrations of commercial sugar syrups, using one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) coupled with multivariate statistical analysis. Sixty-three authentic and 63 adulterated honey samples were analysed. To prepare adulterated honeys, 7 different sugar syrups normally used for nutrition of bees were used. The best discriminant model was obtained by 1D spectra and the leave-one out cross-validation showed a predictive capacity of 95.2 %. Also 2D NMR have furnished acceptable results (cross-validation correct classification 90.5%), although the 1H-NMR sequence is preferable because it is the simplest and fastest NMR technique