High hole mobility and light-harvesting in discotic nematic dendrimers prepared: Via 'click' chemistry

We report a new family of liquid crystalline porphyrin-core dendrimers with coumarin units at the periphery of the dendrimer. These compounds have been prepared by copper-catalyzed azide-alkyne "click" cycloaddition (CuAAC). The mesomorphic properties have been investigated via polarized optical microscopy (POM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The peripheral coumarin units play a key role in the liquid crystal behavior, contributing to the appearance of discotic nematic mesophases with hole mobility values among the highest values reported for discotic liquid crystals (of the order of 1 cm 2 V -1 s -1 ). It has also been demonstrated that excitation of the coumarin moieties leads to energy transfer (antenna effect) to the luminescent porphyrin core. Therefore, this strategy, which involves ''click'' chemistry, has been proven to be a powerful and elegant synthetic tool for the preparation of optoelectronic materials based on complex dendritic architectures

Ethylene signaling triggered by low concentrations of ascorbic acid regulates biomass accumulation in Arabidopsis thaliana

Ascorbic acid (AA) is a major redox buffer in plant cells. The role of ethylene in the redox signaling pathways that influence photosynthesis and growth was explored in two independent AA deficient Arabidopsis thaliana mutants (vtc2-1 and vtc2-4). Both mutants, which are defective in the AA biosynthesis gene GDP-L-galactose phosphorylase, produce higher amounts of ethylene than wt plants. In contrast to the wt, the inhibition of ethylene signaling increased leaf conductance, photosynthesis and dry weight in both vtc2 mutant lines. The AA-deficient mutants showed altered expression of genes encoding proteins involved in the synthesis/responses to phytohormones that control growth, particularly auxin, cytokinins, abscisic acid, brassinosterioids, ethylene and salicylic acid. These results demonstrate that AA deficiency modifies hormone signaling in plants, redox-ethylene interactions providing a regulatory node controlling shoot biomass accumulation

Location of chlorogenic acid biosynthesis pathway and polyphenol oxidase genes in a new interspecific anchored linkage map of eggplant

© Gramazio et al.; licensee BioMed Central. 2014. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated

Diversity and relationships in key traits for functional and apparent quality in a collection of eggplant: fruit phenolics content, antioxidant activity, polyphenol oxidase activity, and browning

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of Agricultural and Food Chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work seehttp://dx.doi.org/10.1021/jf402429kEggplant (Solanum melongena) varieties with increased levels of phenolics in the fruit present enhanced functional quality, but may display greater fruit flesh browning. We evaluated 18 eggplant accessions for fruit total phenolics content, chlorogenic acid content, DPPH scavenging activity, polyphenol oxidase (PPO) activity, liquid extract browning, and fruit flesh browning. For all the traits we found a high diversity, with differences among accessions of up to 3.36-fold for fruit flesh browning. Variation in total content in phenolics and in chlorogenic acid content accounted only for 18.9% and 6.0% in the variation in fruit flesh browning, and PPO activity was not significantly correlated with fruit flesh browning. Liquid extract browning was highly correlated with chlorogenic acid content (r = 0.852). Principal components analysis (PCA) identified four groups of accessions with different profiles for the traits studied. Results suggest that it is possible to develop new eggplant varieties with improved functional and apparent quality.This project has been funded by Universitat Politecnica de Valencia through the grants SP20120681 and PAID-06-11 Nr. 2082, and by Ministerio de Economia y Competitividad Grant AGL2012-34213 (jointly funded by FEDER).Plazas Ávila, MDLO.; López Gresa, MP.; Vilanova Navarro, S.; Torres Vidal, C.; Hurtado Ricart, M.; Gramazio, P.; Andújar Pérez, I.... (2013). Diversity and relationships in key traits for functional and apparent quality in a collection of eggplant: fruit phenolics content, antioxidant activity, polyphenol oxidase activity, and browning. Journal of Agricultural and Food Chemistry. 61(37):8871-8879. https://doi.org/10.1021/jf402429kS88718879613