Effectiveness of the R1-navajo embryo marker on sorting haploids in tropical maize germplasm

Modern maize breeding is currently based on Doubled Haploids (DH) technology. In following the steps to produce inbred lines by DH, sorting the haploids are the most important of them. Haploid inducers usually carry the R1 gene, responsible of purple pigmentation on seeds. Navajo is a typical phenotyping from this gene and leads to purple coloration on endosperm and embryo of the diploids but any pigmentation on haploid kernels. Aimed to analyze the effectiveness of R1-nj on sorting true haploids over tropical sources, two different experiments were conducted. In the first experiment, kernels analyzed came from the following induction cross (L47 x IL47), (P9 x IP9), (2B707 x IL47), and (2B707 x IP9) in which IL47 and IP9 were the tropical haploid inducers. In the second experiment, KHI (Krasnodar Haploid Inducer) was the haploid inducer and three commercial were adopting as sources. Putative haploids were sorted by R1-nj expression and the haploid level was checked by chromosome counting our phenotyping at the flowering stage. Overall, very low true haploid discovery rates were observed. 2B707 was the most reliable source in displaying true haploids. The ratio of this effectiveness among the two ex- periments to R1-nj marker ranged from 8.80 to 30.2%. These results can be explained by the presence of inhibitory genes on the tropical sources. Additionally, at the flowering stage, haploids plants had data of spontaneous doubling collected and summarized. Recovery on the female organs seems to be higher than male. Haploids from the IAC125 source exhibited best fully spontaneous doubling among the sources analyzed

Antiophidic Solanidane Steroidal Alkaloids from Solanum campaniforme

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Three new solanidane alkaloids bearing a 22,23-epoxy ring (1-3) and four known compounds were isolated from leaves of Solanum campaniforme. The structures were determined using spectroscopic techniques, including ID and 2D NMR, and HRESIMS experiments. The antiophidic activity of the alkaloids was tested against Bothrops pauloensis venom. Compounds 1-3 completely inhibited myotoxicity without inhibiting phospholipase A(2) activity of the venom, while hemorrhage and skin necrosis were significantly reduced in the presence of alkaloids 1 and 2.741021682173Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)National Agency FUNCAPCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)National Agency PRONEXConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Cellulose/iron oxide hybrids as multifunctional pigments in thermoplastic starch based materials

Cellulose/iron oxide hybrids were prepared by the controlled hydrolysis of FeC2O4 in the presence of vegetable and bacterial cellulose fibres as substrates. By varying the relative amount of FeC2O4 and NaOH, either hematite or magnetic iron oxides were grown at the cellulose fibres surfaces. This chemical strategy was used for the production of a number of materials, whose coloristic properties associated to their reinforcement role allowed their use as new hybrid pigments for thermoplastic starch (TPS) based products. The TPS reinforced materials were characterized by several techniques in order to evaluate: the morphology and the compatibility between the matrix and the fillers; the mechanical reinforcement effect of the cellulose/iron oxide pigments on TPS and the coloristic properties of the composites. All materials showed good dispersion and strong adhesion for the cellulose/iron oxide nanocomposites in the TPS matrix thus resulting in improved mechanical properties

Cationic release behaviour of antimicrobial cellulose/silver nanocomposites

Silver nanoparticles (NPs) have received great attention, mainly due to their application as antimicrobial agents in diverse products, including textile- and paper-based materials. In this context, straightforward methodologies to monitor their cationic silver release capacity in diverse environments are required due to the rise of manufactured products containing silver NPs. Here, we describe the application of a potentiometric method based on a silver-selective electrode to monitor the kinetics of cationic release from cellulose/silver nanocomposites. We designed a set of experiments to apply this method to nanocomposites with several distinct types of cellulose matrices: vegetable, bacterial and nanofibrillated. The morphological features of the cellulose had a great influence on the distribution of silver NPs within the matrix as well as on the Ag+ release profiles. The cationic release profiles were interpreted based on common models, showing that, for the vegetal and bacterial cellulose nanocomposites, the kinetics is pseudo-first order, while for the nanofibrillated cellulose materials a model based on Fick's power law provided the best fit