Microcapsules of sugarcane bagasse lignin loaded with organic extracts of neem (Azadirachta indica) were prepared and evaluated as potential bioinsecticides. Lignins were extracted and modified by oxidation and acetylation reactions providing different biopolymers. Afterwards, they were characterized through several analytical techniques. The formulations were initially prepared as colloidal suspension of lignin nanoparticles, which were then spraydried. The products were submitted to quality control protocols using high performance liquid chromatography (HPLC), thermal and photochemical degradation studies, followed by biological assays against Spodoptera frugiperda and Diatraea saccharalis. The formulations showed increases in both thermal and photo stability of approximately 40% compared with control samples. All the formulated microparticles were efficient against the insects evaluated and required a shorter time to achieve 100% mortality than the controls. The use of sugarcane bagasse lignins to prepare microparticles improved the resistance of neem extracts against abiotic factors, retaining the biological activity of this biopesticide.

The aim of this work was to prepare and evaluate the properties of biofilms made from pinhão starch in association with xanthan gum and glycerol by casting technique. Tests were run to determine the moisture content, the morphology, the thickness, the water solubility, the glass transition temperature and the gas permeability of these biofilms. Results showed that the biofilms presented appropriate moisture content, high water resistance and uniform thickness. The Scanning Electron Microscopy (SEM) showed not only the presence of cracks on the surface of the biofilm but also some starch granules that did not gelatinize. By Differential Scanning Calorimetry (DSC) was detected the glass transition temperature (-4.8 ± 0.1 °C) and different values of melting temperature (182.3 ± 2.1 °C and 134.9 ± 0.6 °C). The permeability to gases, N 2 and CO 2 , was significantly different. Key words: Araucaria angustifolia, edible films, physical properties Produção e caracterização de biofilmes de amido de pinhão RESUMOO objetivo deste trabalho foi preparar e avaliar as propriedades dos biofilmes feitos a partir de amido de pinhão em associação com goma xantana e glicerol, pela técnica de casting. Testes foram realizados para determinar o teor de umidade, a morfologia, a espessura, a solubilidade em água, a temperatura de transição vítrea e a permeabilidade a gases do biofilme, cujos resultados mostraram que os biofilmes apresentaram teor de umidade adequado, alta resistência à água e espessura uniforme. A microscopia eletrônica de varredura (MEV) indicou não apenas a presença de fissuras na superfície do biofilme mas também alguns grânulos de amido não gelatinizados. Por Calorimetria Diferencial de varredura (DSC) foram detectados a temperatura de transição vítrea (-4,8 ± 0,1 °C) e diferentes valores de temperatura de fusão (182,3 ± 2,1 °C e 134,9 ± 0,6 ºC). A permeabilidade aos gases, N 2 e CO 2 , foi significativamente diferente.

No abstract

A practical, and efficient microwave-assisted, threestep Sonogashira cross-coupling/Deacetonation/Cycloaddition sequence has been developed for the synthesis of a variety of 4-aryl-1,2,3-triazoles from readily available starting materials. The important features of this synthetic sequence include the use of inexpensive 2-methyl-3-butyn-2-ol as an acetylene surrogate, 2-Me-THF as a bio-based solvent, short reaction time, good yields, avoiding the isolation of volatile terminal alkynes.

The di-substituted acetylene residue in the title compound, C11H11NO3, is capped at either end by di-methylhydroxy and 4-nitrobenzene groups; the nitro substituent is close to co-planar with the ring to which it is attached [dihedral angle = 9.4 (3)°]. The most prominent feature of the molecular packing is the formation, via hydroxy-O—H...O(hydroxy) hydrogen bonds, of hexameric clusters about a site of symmetry \overline{3}. The aggregates are sustained by 12-membered {...OH}6 synthons and have the shape of a flattened chair. The clusters are connected into a three-dimensional architecture by benzene-C—H...O(nitro) interactions, involving both nitro-O atoms. The aforementioned interactions are readily identified in the calculated Hirshfeld surface. Computational chemistry indicates there is a significant energy, primarily electrostatic in nature, associated with the hydroxy-O—H...O(hydroxy) hydrogen bonds. Dispersion forces are more important in the other identified but, weaker intermolecular contacts.