ABSTRACT. Since the composition of honey varies with the species of bee as well as flowering and geographical aspects, this study aimed to evaluate the physicochemical and bioactive properties of Apisand stingless bees’honey from the Brazilian Caatinga. Samples of different species of Apis mellifera L.Meliponini (Melipona subnitida, Frieseomellita varia, Melipona mandacaia, Plebeia sp.) and Apis mellifera L.werecollected from honey producersin the state of Rio Grande do Norte. Honey from A. mellifera and stingless bees showed physicochemical differences in some parameters, especially in moisture, free acidity, HMF, water activity, sugars and electric conductivity. There were no differences in color between honeys from A. mellifera and stingless bees. Honeys fromPlebeia sp., F. varia and A. mellifera showed higher antioxidant capacity followed by honeys fromM. mandacaia and M. subnitida. Flavonoids had little influence on the differentiation of antioxidant activities of stingless bees, while the opposite occurred with the phenolic content, where honeys with the highest levels of phenolic also showed higher antioxidant capacity. ABSTRACT aspects beeshoney Caatinga LMeliponini L Meliponini subnitida sp. sp Lwerecollected werecollected Norte A parameters moisture acidity HMF activity conductivity F fromM M content

RESUMO A indústria têxtil consome um volume significativo de água no processo de tingimento das fibras. As águas residuais geradas no processamento, além de turvas, devido à presença de corantes que não se fixam na fibra durante o processo de tingimento, são prejudiciais ao ambiente aquático e também aos seres humanos. Esse efluente deve passar por um processo de tratamento antes de ser lançado em corpos hídricos. O tratamento de águas contaminadas com o uso de bioadsorventes possui como vantagens o baixo custo de material e reciclagem de resíduo natural. Baseado no exposto, o objetivo deste trabalho foi avaliar a capacidade de adsorção do corante têxtil Azul Reativo BF-5G em casca de mandioca (Manihot Esculenta Crantz), resíduo proveniente da indústria de farinha de mandioca. A casca de mandioca foi lavada, seca e classificada. Os ensaios de adsorção, em banho finito, foram realizados em diferentes condições de pH, granulometria e temperatura. As capacidades máximas de adsorção, em 24 horas de contato, para as diferentes condições de pH, granulometria e temperatura, foram as seguintes: (qmáx=85,18 mg.g-1; pH=1; 30 °C; 16 mesh); (qmáx=52,30 mg.g-1; pH=0; 30 °C; 32 mesh); (qmáx=92,92 mg.g-1; pH=0; 30 °C; 48 mesh). O processo de adsorção foi espontâneo e exotérmico, o que leva a concluir que a casca de mandioca (Manihot Esculenta Crantz) é um potencial adsorvente para o corante Azul Reativo BF-5G, garantindo economia e praticidade no tratamento desse efluente.

ABSTRACT The textile industry consumes a significant amount of water in the fiber dyeing process. The wastewater generated in the processing, in addition to turbid, due to the presence of dyes that do not stick to the fiber during the dyeing process, are harmful to the aquatic environment and also to humans. This effluent must undergo a treatment process before being released into water bodies. The treatment of contaminated water with the use of bioadsorbers has the advantages of low material cost and recycling of natural waste. Based on the above, the objective of this work was to evaluate the adsorption capacity of the textile dye Blue Reactive BF-5G in cassava peel (Manihot Esculenta Crantz), residue from the cassava flour industry. The cassava peel was washed, dried and classified. The adsorption tests, in finite bath, were carried out under different conditions of pH, granulometry and temperature. The maximum adsorption capacities, in 24 hours of contact, were as follows: (qmax=85.18 mg.g-1; pH=1; 30 °C; 180 rpm; 16 mesh); (qmax=52.30 mg.g-1; pH=0; 30 °C; 180 rpm; 32 mesh); (qmax=92.92 mg.g-1; pH=0; 30 °C; 180 rpm; 48 mesh). The adsorption process was spontaneous and exothermic, which leads to the conclusion that the cassava peel (Manihot Esculenta Crantz) is a potential adsorbent for the Reactive Blue BF-5G dye, ensuring economy and practicality in the treatment of this effluent.

ABSTRACT. The aim of this study was to evaluate the physicochemical quality and bioactive compounds of Apis mellifera honey as well as the alterations in the quality of A. mellifera honey after being used in the feeding of Melipona subnitida colonies. A. mellifera honeys were collected in apiaries, homogenised and used as feed for M. subnitida bees for 30 days. Every five days, honey samples were collected and evaluated for physicochemical characteristics and bioactive compounds. The treatments consisted of natural honeys of A. mellifera and M. subnitida and honey of M. subnitida bee after being fed with A. mellifera honey (modified honey). M. subnitida bees, when fed with honey from A. mellifera, modified some of its characteristics, such as moisture, reducing sugars, diastase activity, colour and flavonoid content. Natural and modified honeys of A. mellifera were similar to each other and different from M. subnitida honey in terms of minerals, free acidity, electrical conductivity, phenolic content and antioxidant activity. Treatments were similar in terms of sucrose, insoluble matter, hydroxymethylfurfural and water activity. In general, the quality attributes of the modified honey were closer to the honey of A. mellifera than to the natural M. subnitida honey.

ABSTRACT The synthesis of ceramic materials such as ferrite has been widely studied in recent years, due to their properties that make these materials have excellent applications in technology, as well as in photocatalytic processes and as catalysts. To obtain the copper ferrite phase the EDTA-Citrate complexation method was used, varying pH (5, 7 and 9), temperature (600, 800 and 1000 °C) and calcination time (2, 7 and 12 h). Composition, morphology and structural analyzes were performed by X-ray fluorescence spectroscopy, X-ray dispersive energy, scanning electron microscopy and X-ray diffraction, respectively. Crystalline phase of copper ferrite (CuFe2O4) with tetragonal structure and secondary phase of Fe2O3 and CuO was verified by XRD analysis. Regarding the chemical composition analyzes, percentage deviations of the samples and the theoretical value for copper and iron were calculated. It was obtained minimum values of 0.16 - 0.08% (atomic%, EDS) and 16 - 8% (atomic%, XRF) in relation to copper and iron, respectively, for the sample obtained under pH 9, calcined at 600 °C for 12 h. The variation of the synthesis condition via EDTA-Citrate directly influenced the morphology of copper ferrite, presenting agglomerated particles, pore formation, irregular spheres, and even powder sintering.

In this paper, NiMoO4 powder was synthesized by the complexation method combining EDTA-Citrate. The behavior of the NiMoO4 material in the ethyl transesterification reaction was evaluated by analyzing the acidity index under specified reaction conditions. The results showed that NiMoO4 crystallized at 800 °C with a total mass loss of 85%, presenting a monoclinic structure, free of secondary phases, high degree of crystallinity and average crystallite size of 140 nm. The particles had heterogeneous sizes and shapes, but with well-defined contours. The increase in the mass of NiMoO4 in the reaction medium reduced the acidity index (0.8 mgKOH.g-1 with 15 wt.%). Despite the use of the minimum molar ratio (1:3), the ethyl route being less reactive and the use of the operating temperature close to the alcohol evaporation temperature, NiMoO4 showed promising catalytic potential in the transesterification process.

RESUMO Filmes biopoliméricos podem substituir vantajosamente polímeros de origem petroquímica em diversas áreas, como a de embalagem de frutas e hortaliças. Como esses produtos apresentam respiração e transpiração mesmo após a colheita, as propriedades de barreira e de resistência à água do material são cruciais para o cumprimento de seu propósito. Neste trabalho foram obtidos filmes biopoliméricos baseados em fécula de mandioca (0-3%), quitosana (0-3%), cera de carnaúba (0; 0,2%) e glicerol (0,6%) e suas propriedades de interesse foram determinadas. A incorporação da cera reduziu em média 20% a taxa de permeabilidade ao vapor d’água (TPVA), em relação aos filmes sem cera. Dentre os filmes contendo cera, 1c (3% de fécula) e 2c (2% de fécula e 1% de quitosana) apresentaram valores mais baixos de TPVA, 12,55 g/m²h e 12,42 g/m²h respectivamente, sendo então submetidos a outras caracterizações que revelaram que a substituição parcial da fécula pela quitosana não afetou a espessura dos filmes, causou decréscimo de 14% em sua solubilidade e melhorou suas propriedades mecânicas, o que significa aumento em seu potencial para a aplicação pretendida.

ABSTRACT Biopolymer films can advantageously substitute polymers of petrochemical origin in several areas, such as packaging of fruits and vegetables. As these products exhibit breathability and perspiration even after harvesting, barrier properties and water resistance of the packaging material are crucial. In this work, biopolymer films based on cassava starch (0-3%), chitosan (0-3%), carnauba wax (0; 0.2%) and glycerol (0,6%) were obtained and their properties of interest were determined. The wax incorporation reduced on average 20% of the water vapor transmission rate, WVTR, in relation to the films without wax. Among the films containing wax, 1c (3% starch) and 2c (2% starch; 1% chitosan) presented lower values of WVTR, 12.55 g / m²h and 12.42 g / m²h respectively, were then subjected to other characterizations that revealed that the partial replacement of starch by chitosan did not affect the film thickness, caused a decrease of 14% in its solubility and improved mechanical properties, which means increase in its potential for the intended application.

RESUMO A indústria têxtil produz efluentes ricos em corantes que, quando liberados em corpos hídricos, dificultam a penetração da luz solar, prejudicando os processos fotossintéticos. Além disso, os corantes foram indicados como substâncias potencialmente tóxicas. Em geral, os processos de remoção desses contaminantes têm sido muito estudados, destacando-se a técnica de adsorção por sua alta eficiência, além de vantagens operacionais e a possibilidade de reutilização de resíduos agrícolas como adsorventes, beneficiando o meio ambiente e reduzindo custos. O presente trabalho teve como objetivo estudar o desempenho do mesocarpo de coco utilizado como adsorvente no processo de branqueamento de efluente sintético contendo 25 g.L-1 de corante vermelho reativo 195. Os adsorventes foram caracterizados por granulometria, análise termogravimétrica e potencial de carga zero. Realizou-se estudo cinético e de equilíbrio, aplicando-se modelos cinéticos e isotermas de adsorção. O adsorvente exibiu eficiência de remoção de 89,92 % em 120 min. A capacidade máxima de adsorção foi de 24,04 g.g-1 a 30 °C. O estudo cinético mostrou que os dados foram melhor ajustados pelo modelo de Elovich, indicando quimissorção lenta. O estudo termodinâmico mostrou que o processo de adsorção é exotérmico e espontâneo para todas as temperaturas avaliadas.

ABSTRACT The textile industry produces dye-rich effluents that when released in hydric bodies hamper the penetration of sunlight, impairing photosynthetic processes. Besides that, dyes have been indicated as potentially toxic substances. In general, the processes of removing of these contaminants have been much studied, with the technique of adsorption standing out for its high efficiency, in addition to operational advantages and the possibility of reuse agricultural waste as adsorbents, benefiting the environment and reducing costs. The present work had as objective to study the performance of coconut mesocarp utilized as adsorbent in the bleaching process of synthetic effluent containing 25 g.L-1 of reactive red 195 dye. The adsorbent were characterized by granulometry, thermogravimetric analysis and zero point charge. Kinetic and balance study was realized, applying kinetic models and adsorption isotherms. The adsorbent exhibited removal efficiency of 89.92 % in 120 min. The maximum adsorption capacity was 24.04 g.g-1 at 30 °C. The kinetic study showed that the data was better adjusted by an Elovich equation, indicating slow chemisorption. The thermodynamic study exhibited that the adsorption process is exothermic and spontaneous for all the temperatures evaluated.

Concern for sustainable development has provided significant improvements in the development of biodegradable materials. This work aims to evaluate, through a central composite design (CCD), the mechanical properties of cassava starch-based biocomposites manufactured with different compositions of carnauba wax (CW), sisal fiber (SF) and glycerol (G). The biocomposites were obtained by casting method. The tensile strength (TS), modulus of elasticity (ME) and elongation at break (El) for the biocomposites were determined by tensile tests. Representative models were obtained to explain changes in mechanical properties of biocomposites as function of composition variables. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to elucidate interactions between the starch matrix and additives A biocomposite with 7.5% sisal fiber, 10% carnauba wax and 10% glycerol showed the best properties to possible applications.

This work aims investigate the changes on tensile properties of biocomposites obtained by addition of carnauba wax and coconut fibers in a corn starch matrix. The influence of carnauba wax and coconut fibers contents on tensile strength, modulus of elasticity and elongation at break was studied using a response surface methodology. A central composite design based on three levels of carnauba wax content (0, 10 and 20 %) and coconut fibers content (0, 10 and 20 %) was elaborated. Empirical models were obtained to describe these properties as function of coconut fiber and carnauba wax contents. Optical microscopy was carried out to visualize the dispersion and interactions between coconut fibers, carnauba wax and starch matrix in the biocomposites. In presence of carnauba wax, the biocomposite became more compact and with a better interaction between the corn starch-based matrix and coconut fibers reinforcement. It was observed that tensile strength and modulus of elasticity rise with the increase in carnauba wax and coconut fiber contents. Moreover, the elongation at break increases with the addition of coconut fiber, while a decrease in the values of this property occurs with the addition of carnauba wax.

BaCeO3-based ceramics are ionic and electronic conductors that can be applied to oxygen sensors, solid oxide fuel cells and oxygen permeable membranes. However, the low chemical stability at high temperatures of these materials motivates studies involving doping of A and/or B sites of the perovskite structure. In this context, the present work aimed to synthesize a new BaCe0.8Pr0.05Cu0.15O3-δ material using the chemical route of complexation which combines EDTA-Citrate with pH variation. The powders obtained at pH 3 or 11 and calcined up to 900 ºC are thermally unstable. The cubic perovskite BaCe0.8Pr0.05Cu0.15O3-δ with crystallite size between 99.4 nm and 131.6 nm was obtained along with barium carbonate traces. In the powders calcined at 1000 ºC the pH increase decreases the amount of barium carbonate (17.3% to pH 3, 3.4% to pH 7 and 1.8% to pH 11), but increases the size of grains with irregular shapes.

Biopolymer films have several industrial applications because they are environmentally sustainable. Cassava starch is a biopolymer that is easily available, but has limitations: it is hydrophilic, poorly resistant and degradable. The improvement of these properties was proposed in this research from the use of bentonite clay (BT) as a filling material. The compatibilization of this in the polymer matrix was obtained by ion exchange with an organic anionic surfactant. The formation of intercalated or exfoliated starch nanocomposites in the presence of natural or modified clay was characterized by XRD, FTIR, AFM and SEM. The improvement of water vapor, thermal and mechanical properties was investigated by WVP, solubility, TGA and tensile test. The starch nanocomposites in the presence of modified clay showed a better result than those of natural clay. There was no significant difference in the color of the starch film in the presence of the natural or modified clay.

Coatings technologies with biopolymeric films are effective in maintaining the chemical and sensory characteristics of several fruits. Cassava starch is an attractive biopolymeric because of its renewable characteristics and low cost, but it has a high transfer rate of water vapor. Hydrophilic compounds of organically modified montmorillonite clay by ion exchange can be used to improve the limiting properties of starch in exchange for additives such as lipids. The solutions prepared with 5% m/v starch / 5% m/m cationic / anionic clay and uncoated were applied in caja fruit, harvested at physiological maturity, selected for absence of defects and color uniformity. The experimental design was performed with four storage times (0, 3, 6 and 9 days). For the maturation index, there was an isolated effect of the type of coating and storage time, showing the composite films of modified cationic clay with greater MI of the fruits in comparison to the control fruits.

Films and edible coatings of natural polymers have been proposed as an attractive alternative for conventional plastic packaging because of their excellent biodegradability and biocompatibility. However, natural polymers, like chitosan, are hydrophilic and present poor water barrier properties. The addition of wax or other hydrophobic substances decreases water permeability of natural polymers but can increases their opacity.The objective of this work was to produce biofilms based on chitosan and different concentrations of carnauba wax and analyze their optical and barrier properties. The films were obtained by dissolving chitosan in acetic acid. Carnauba wax was incorporated into film-forming solutions at0, 15, 30, 40 and 50% (w/w). The opacity increased with higher concentrations of wax, the film with 50% of wax showed the highest value with an increase of 10.5% compared to the control film. The water vapor permeability decreased from 2.73 g.mm/kPa.m2.h (0% of wax) to 0.77 g.mm/h.kPa.m2 (40% of wax). The solubility decreased to about 60% over the control films, and the contact angle increased from 53º to 83º, in film with 0 and 50% of wax, respectively.