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The synthesis by coprecipitation of Layered Double Hydroxides (LDHs) is governed by the stages of nucleation and crystal growth associated with the efficiency of the mixing and dispersion process of the reagents. Mixing efficiency is related to process variables, such as agitation speed, type of impeller and baffles presence, among others. In this context, this work proposes an analysis of these variables in a batch reactor, using a 23 factorial design employing the factors: acceleration speed (200 and 1000 rpm), mixing time (2 and 18 h) and presence or absence of baffles. The results were evaluated quantitatively (amount of LDH produced, time and amount of base for the formation of LDHs to begin) and qualitatively (mixing aspects, sedimentation ad grinding). The significant factors affecting the amount of LDH produced (51.94–80.81 g) were agitation speed and aging time. These factors were also correlated with the structural characteristics of the materials produced, such as crystallinity, crystallite size (70.99–174.79 nm), surface area (69.81–97.62 m2/g), pore volume (0.28–0.59 cm3/g), and pore diameter (11.40–34.66 nm). LDHs produced at higher agitation rates (1000 rpm) and longer aging times (18 h) yielded higher quantities of materials (80.81 g) with improved structural characteristics. The study highlights the importance of systematically exploring the synergistic effect between process variables, emphasizing the research potential in this area.

Abstract The Pyroligneous extract is a product from the combustion of plant biomass with applications in the fields of health, industrial chemistry, and agriculture. The discovery of new molecules with therapeutic potential and of natural origin continues to be one of the great challenges for research centres around the world. The following work aims to analyze, through a technological prospection, the use of pyroligneous extracts for therapeutic purposes. To carry out the study, searches were carried out in documents deposited in Brazil, Europe, and the United States and searched on platforms specialized in patents. The number of inventions using pyroligneous extract with therapeutic applications is still quite small, however, innovations have been observed for the treatment of diseases of great clinical relevance such as cancer and hypertension. The systematic mapping of innovations is of great importance for the development of new technologies.

Abstract Phenolic compounds are natural dyes contained in sugarcane juice and represent an important parameter in industrial processing, as they significantly affect the color formation of raw sugar. This study investigated the relationship between color formation and phenolic compounds during a Very High Polarization (VHP) sugar manufacturing process, in which the RB92579 genotype represents about 50% of the processed sugarcane. The products evaluated during the industrial processing of sugarcane were: raw juice, mixed juice, lime-treated juice, clarified juice, syrup, massecuite, and VHP sugar. The polyphenols catechin (CAT), chlorogenic acid (CGA), caffeic acid (CAF), vanillin (VAN), syringaldehyde (SYR), p-coumaric acid (p-COU), coumarin (CUM), and rutin (RUT) were quantified by high-performance liquid chromatography (HPLC). The highest concentrations of CGA and SYR were obtained from the sucrose crystallization product (massecuite), similarly to the parameters of color, total phenols and the total polyphenol content. CGA was the predominant polyphenol in the samples of clarified juice, syrup, massecuite and VHP sugar, with the latter presenting concentrations above 50%. The presence of phenolic compounds provided different indices of color during the production process. In this context, chlorogenic acid (CGA) was the compound that presented the most expressive results, contributing significantly to the formation of color in sugarcane processing products, which is a fact that has not yet been reported in the literature. The color of the VHP sugar crystals also had a positive relationship with the concentration of phenolics, with greater evidence for CGA.

ABSTRACT Dry rot of yam (Dioscorea spp.) caused by Scutellonema bradys and Pratylenchus spp. has restricted yam production in Brazil. Plant-based products can be useful reducing nematode damages. The objectives of this study were to evaluate the nematostatic and nematicidal in vitro activities of pyroligneous extracts from Cocos nucifera, Syagrus cearensis, S. coronata, and Wodetia bifurcata palms against S. bradys and to evaluate the effect of C. nucifera pyroligneous extract in the treatment of yam tubers infected by S. bradys and Pratylenchus sp. under greenhouse conditions. The pyroligneous extracts obtained at pyrolysis temperatures of 400, 500, 600, and 700 ºC, and at different concentrations, were tested for nematode immobility and mortality in Kline slides. Cocos nucifera pyroligneous extract obtained at 400 °C and 1% concentration was tested on yam tubers, under different immersion periods. Six months after yam planting the nematode populations were evaluated. All pyroligneous extracts inhibited the mobility and caused mortality to S. bradys, however 100% inhibition of both variables was achieved at concentrations varying from 0.75 to 2%, depending on the pyrolysis temperatures. The reproduction factor was reduced in 43% by treating infected yam tubers with pyroligneous extract from C. nucifera.

RESUMO: Dentre os métodos de controle da propagação da doença do anel-vermelho, o uso de feromônios associado às armadilhas com alimentos tem se mostrado eficiente na captura do inseto-praga. O feromônio utilizado é denominado como Rincoforol e é disponibilizado em microtubos. Estudos estão em desenvolvimento para aplicar o agente de captura em matrizes sólidas. Nesse contexto, o presente trabalho foi realizado a fim de avaliar a capacidade adsortiva do carvão ativado do endocarpo do coco de dendê na incorporação do Rincoforol para liberação controlada do feromônio em campo. Para isso, foi realizado um planejamento experimental completo (23) a fim de avaliar a influência do uso de estabilizante junto ao feromônio, da granulometria do carvão ativado e do número de furos do sachê no processo de liberação, obtendo como resposta a perda de massa. Verificou-se que a condição que favorece a liberação controlada do feromônio, ao comparar com a liberação realizada em eppendorf, foi o uso do Rincoforol formulado (com estabilizante) adsorvido em carvão com menor granulometria (35 < ᴓ < 28 mesh) e sachê com 5 furos, condição encontrada no experimento de número 3, o qual apresentou uma menor perda de massa. PALAVRAS-CHAVE: Feromônio; Adsorção; Planejamento Experimental.

The use of Biodiesel allows several advantages over diesel fuels such as lower pollutants emission profiles into the atmosphere, hand jobs posts creating, and reduction of imported diesel fuel. Since the program has begun, the soybean oil has been used as mainly raw material to biodiesel production. In fact, this culture is the only that can afford the production needs from biodiesel facilities. However, this oil is a commodity and alternatives fatty materials sources have to be found in order to increase the competitiveness of the process and release the oilseed production to food industry. This work has focused on evaluating the potential use of castor oil, ouricuri, babassu, castanets, macauba and seeds of passion fruit and pinecone as alternative sources to biodiesel production. The results have shown that the evaluation of moisture content of the samples plays an important role before oil content determination and except the seeds of passion fruit, all of them shown oil potential to supply biodiesel production needs.