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1.
Food Res Int ; 169: 112859, 2023 07.
Article in English | MEDLINE | ID: mdl-37254433

ABSTRACT

The study of the evolution of color of alcoholic beverages subjected to accelerate maturation process using heat-treated French oak wood fragments is presented. The results show that it is possible to obtain tonalities like aged beverages in 4 weeks. In this sense, the fragments conditioned at 150 °C (light toasted) proportionated colors like white wine, pale straw, and pale gold. On the other hand, the fragments that received a heat treatment at 200 °C (medium toasted) present yellow tones such as old gold, amber, and deep gold. Finally, the fragments treated at 250 °C (heavily toasted) are those with the most intense yellow tones, classified as sweet chestnut, sherry, russet, muscat, and tawny. The studies of kinetic maturation concluded that the mathematical model of parabolic diffusion could correctly describe the process. Based on this, it is concluded that the heat treatment increases the cavities of the most exposed surface of the wood, increasing the maximum humidity of the materials by 20 %; in such a way that during the first two weeks, there is a diffusion of the solution to the active sites. Wood bioactive compounds on the outer surface achieve a rapid extraction, such as flavonoids, which oxidize rapidly within the solution, generating an increase in yellow color. The previous results were corroborated in a real case analysis using Tequila which can be concluded that the proposed process can give the beverage similar colors to an aged, extra-aged, and ultra-aged class in less than 4 weeks.


Subject(s)
Fagaceae , Wine , Wine/analysis , Hot Temperature , Wood/chemistry , Nuts
2.
Polymers (Basel) ; 15(9)2023 Apr 30.
Article in English | MEDLINE | ID: mdl-37177299

ABSTRACT

Natural fibers have some advantages in comparison to synthetic fibers, especially because they are more environmentally friendly. For this reason, using them as a reinforcement for polymeric matrices is growing exponentially. However, they present the disadvantage of having the hydrophilic nature, which strongly reduces the interface interaction. Sedge fibers have been investigated when reinforcing an epoxy matrix in terms of ballistic properties and mechanical performance. Aiming to enhance the fiber-matrix interface, an alkali treatment was proposed. The group conditions were divided into three NaOH concentrations (3%, 5%, and 10%), as well as the three periods of immersion (24, 48, and 72 h). Therefore, nine different conditions were investigated in terms of their thermal behaviors, chemical structures, physical structures, and morphological aspects. Based on TGA curves, it could be noticed that treatments related to 3% NaOH for 24 h and 48 h exhibited better thermal stability properties. For the time of 48 h, better thermal stability with for a decay of the thermal DSC curve was shown for all treatment conditions. The FTIR spectra has shown a reduction of waxes for higher NaOH concentrations. The XRD diffractogram exhibited an increase in the crystallinity index only for 5% NaOH and an immersion time of 48 h. The morphological aspects of fibers treated with 5% and 10% of NaOH have shown that the treatments have damaged the fiber, which highlighted the crystallinity index reductions.

3.
J Pharm Sci ; 112(6): 1523-1538, 2023 06.
Article in English | MEDLINE | ID: mdl-36822273

ABSTRACT

Nifurtimox is a nitroheterocyclic drug employed for treatment of trypanosomiases (Chagas disease and West African sleeping sickness); its use for certain cancers has also been assessed. Despite having been in the market for over 50 years, knowledge of nifurtimox is still fragmentary and incomplete. Relevant aspects of the chemistry and biology of nifurtimox are reviewed to summarize the current knowledge of this drug. These comprise its chemical synthesis and the preparation of some analogues, as well as its chemical degradation. Selected physical data and physicochemical properties are also listed, along with different approaches toward the analytical characterization of the drug, including electrochemical (polarography, cyclic voltammetry), spectroscopic (ultraviolet-visible, nuclear magnetic resonance, electron spin resonance), and single crystal X-ray diffractometry. The array of polarographic, ultraviolet-visible spectroscopic, and chromatographic methods available for the analytical determination of nifurtimox (in bulk drug, pharmaceutical formulations, and biological samples), are also presented and discussed, along with chiral chromatographic and electrophoretic alternatives for the separation of the enantiomers of the drug. Aspects of the drug likeliness of nifurtimox, its classification in the Biopharmaceutical Classification System, and available pharmaceutical formulations are detailed, whereas pharmacological, chemical, and biological aspects of its metabolism and disposition are discussed.


Subject(s)
Chagas Disease , Pharmacy , Humans , Nifurtimox/chemistry , Nifurtimox/pharmacology , Nifurtimox/therapeutic use , Chagas Disease/drug therapy , Pharmaceutical Preparations
4.
Rev. Ciênc. Agrovet. (Online) ; 21(1): 56-65, mar. 2022. graf, tab
Article in Portuguese | VETINDEX | ID: biblio-1366125

ABSTRACT

O segmento de produção de papel de fibra longa no Brasil está concentrado na utilização de duas espécies do gênero Pinus (P. taeda e P. elliottii). Assim, éfundamental avaliar novas espécies, visando ampliar as alternativas para esse segmento. Opresente estudo teve como objetivo avaliar as propriedades físicas, químicas e anatômicas da madeira de Pinus greggii visando a produção de polpa celulósica. Foram utilizadas três árvores, com seteanos de idade, das quais foram retirados discos ao longo do fuste. Estes foram utilizados para avaliar as propriedades físicas (densidade básica média e ponderada), químicas (teores de cinza, extrativos, lignina e holocelulose) e anatômicas (dimensões dos traqueídeos e indicadores anatômicos). De acordo com a caracterização físicada madeira, obteve-se um valor médio de densidade básica de 0,346 g.cm-3e ponderadode 0,343 g.cm-3, o que permite classificá-la como leve ou de baixa densidade. Em relação à composição química, a espécie apresentou elevados teores de lignina e extrativos (34,83% e 6,25%, respectivamente) e baixos teores de holocelulose (58,92%) e cinza (0,20%). Para as dimensões dos traqueídeos obtiveram-se valores médios de 2,31 mm de comprimento, 41,30 µm de largura, 34,81 µm de diâmetro do lúmen, e 3,25 µm de espessura da parede celular. Quanto aos resultados dos índices de qualidade, a espécie obteve destaque para a fração parede (15,96%), coeficiente de flexibilidade (84,31%), índice de Runkel (0,19) e índice de enfeltramento (55,15). De modo geral, a madeira de P. greggiiapresenta potencial para produção de polpa celulósica, destacando-se pelos indicadores anatômicos e pelas dimensões dos traqueídeos, que são semelhantes aos valores encontrados para P. taedana mesma idade. Entretanto, possui elevados teores de lignina e extrativos, que podem aumentar o consumo de reagentes e diminuir o rendimento do processo de polpação, o que precisa ser comprovado em estudos com esta temática.(AU)


The long fiber paper production segment in Brazil is restrict on the use of only two species of the Pinusgenus (P. taedaand P. elliottii), therefore, it is essential to evaluate new species, aiming to expand the alternatives for this segment. In this sense, the present study aimed to evaluate the physical, chemical and anatomical properties of Pinus greggiiwood aiming at the pulp production. For this, three 7-year-old trees were used, from which disks were removed along the stem. These were used to evaluate physical (average and weighted basic density), chemical (ash, extractive, lignin and holocellulose) and anatomical (tracheid dimensions and anatomical indicators) properties. According to the physical characterization, an average value of basic density of 0.346 g.cm-3and weighted of 0.343 g.cm-3was obtained, which allows classifying it as light or low density. Regarding the chemical composition, the species showed high levels of lignin and extractives (34.83% and 6.25%, respectively) and low levels of holocellulose (58.92%) and ash (0.20%). For the tracheids dimensions, mean values of 2.31 mm in length,41.30 µm in width, 34.81 µm in lumen diameter, and 3.25 µm in cell wall thickness were obtained. As for the results of the quality index, the species stood out for the wall fraction (15.96%), flexibility coefficient (84.31%), Runkel index (0.19) and felting index (55.15). In general, the P. greggiiwood presents potential for the pulp production, standing out for its anatomical indicators and for the tracheids dimensions, which are similar to the values found for P. taedaat the same age. However, it has high levels of lignin and extractives, which can increase the consumption of reagents and decrease the yield of the pulping process, which needs to be proven in studies on this topic.(AU)


Subject(s)
Wood , Pinus , Cellulose/biosynthesis
5.
Polymers (Basel) ; 13(11)2021 May 26.
Article in English | MEDLINE | ID: mdl-34073343

ABSTRACT

The call to use biodegradable, eco-friendly materials is urgent. The use of biopolymers as a replacement for the classic petroleum-based materials is increasing. Chitosan and starch have been widely studied with this purpose: to be part of this replacement. The importance of proper physical characterization of these biopolymers is essential for the intended application. This review focuses on characterizations of chitosan and starch, approximately from 2017 to date, in one of their most-used applications: food packaging for chitosan and as an adsorbent agent of pollutants in aqueous medium for starch.

6.
J Pharm Sci ; 108(5): 1848-1856, 2019 05.
Article in English | MEDLINE | ID: mdl-30599168

ABSTRACT

Orotic acid (OA), a heterocyclic compound also known as vitamin B13, has shown potent antimalarial and cardiac protection activities; however, its limited water solubility has posed a barrier to its use in therapeutic approaches. Aiming to overcome this drawback, OA freeze-dried nanocrystal formulations (FA, FB, and FC) were developed by using the high-energy milling method. Polysorbate 80 (FA) and povacoat® (FC) were used alone and combined (FB) as stabilizers. Nanocrystals were fully characterized by dynamic light scattering, laser diffraction, transmission electron microscopy, thermal analysis (thermogravimetry and derivative thermogravimetry, and differential scanning calorimetry), and X-ray powder diffraction revealing an acceptable polydispersity index, changes in the crystalline state with hydrate formation and z-average of 100-200 nm, a remarkable 200-time reduction compared to the OA raw material (44.3 µm). Furthermore, saturation solubility study showed an improvement of 13 times higher than the micronized powder. In addition, cytotoxicity assay revealed mild toxicity for the FB and FC formulations prepared with povacoat®. OA nanocrystal platform can deliver innovative products allowing untapped the versatile potential of this drug substance candidate.


Subject(s)
Nanoparticles/chemistry , Orotic Acid/chemistry , Solubility/drug effects , Water/chemistry , Animals , Calorimetry, Differential Scanning/methods , Cell Line , Chemistry, Pharmaceutical/methods , Drug Compounding/methods , Freeze Drying/methods , Mice , Particle Size
7.
Braz. J. Pharm. Sci. (Online) ; 53(4): e00216, 2017. tab, graf
Article in English | LILACS | ID: biblio-889428

ABSTRACT

ABSTRACT The search for new pharmaceutical dosage forms and different drug delivery systems already used in therapeutics is a global trend, serving as an opportunity to expand the portfolio for the pharmaceutical industry. In this context, multiparticulate systems, such as pellets, granules, and minitablets, represent an attractive alternative, given the range of possibilities they provide. Among the methods used in the production of these systems, we highlight the process of extrusion-spheronization for pellet manufacture, wet granulation and hot-melt extrusion for the obtention of granules, and direct compression for minitablets. Although highly versatile, depending on the technology chosen, many processes and formulation variables can influence the ensuing stages of manufacture, as well as the final product. Therefore, the characterization of these small units is of fundamental importance for achieving batch homogeneity and optimal product performance. Analyses, including particle size distribution, morphology, density, porosity, mechanical strength and disintegration, are example tests used in this characterization. The objective of this review was to address the most widely used tests for the physical evaluation of multiparticulate systems.


Subject(s)
Pharmaceutical Preparations , Physical Phenomena/classification , Drug Compounding/statistics & numerical data , Straining of Liquids , Drug Delivery Systems , Dosage Forms , Test Taking Skills/methods
8.
J Pharm Sci ; 105(3): 1258-68, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26886308

ABSTRACT

Mixing aqueous solutions of sodium diclofenac (DIC-Na) and ranitidine hydrochloride (RAN·HCl) afforded an off-white solid (DIC-RAN) that was investigated from the microscopic, thermal, diffractometric, spectroscopic, and functional (chemometrics-assisted dissolution) points of view. The solid has a 2:1 (DIC:RAN) molar ratio according to (1)H nuclear magnetic resonance spectroscopy. It is thermally stable, displaying a broad endothermic signal centered at 105°C in the thermogram, and its characteristic reflections in the powder X-ray diffractogram remained unchanged after a 3-month aging period. Scanning electron microscopy micrographs uncovered its morphology, whereas the spectral data suggested an interaction between the carboxylic acid of DIC and the alkyldimethylamino moiety of RAN. The dissolution of DIC-RAN was monitored at different pH values by an ultraviolet/chemometrics procedure, being complete within 5 min at pH 6.8. This compares favorably with the dissolution of a DIC-Na sample of the same particle size.


Subject(s)
Diclofenac/chemistry , Ranitidine/chemistry , Chemical Precipitation , Microscopy, Electron, Scanning/methods , Particle Size , Powders/chemistry , Solubility , Temperature , X-Ray Diffraction/methods
9.
J Pharm Sci ; 104(7): 2241-54, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25952004

ABSTRACT

Development and optimization of a hydrogel with impregnated silver sulfadiazine was pursued, for antimicrobial topical applications. The selected hydrogel exhibited a homogeneous appearance, with whitish colloration and devoid of any fractures or cracks. The content in impregnated silver sulfadiazine was within established limits (1%, w/w) with a standard deviation of up to 1.28%. The hydrogel presented a good characteristic in relation to release of the active antimicrobial principle, verified through swelling tests and antimicrobial activity. The swelling tests indicated a higher increase in weight during the first 6 h of contact with a moist environment, with a maximum value of 266.00 ± 0.81, and with maintenance of the original shape of the hydrogel. The impregnated silver sulfadiazine presented antimicrobial activity, as expected, indicating a prolonged release of the drug. The infrared spectra of the hydrogel with impregnated silver sulfadiazine indicated that the drug did not engage in any bonds with the polymeric matrix, which otherwise could have reduced its antimicrobial activity. The mechanical resistance tests produced good results, indicating that the hydrogels may be utilized in different locations of the human body with skin lesions.


Subject(s)
Anti-Bacterial Agents/chemistry , Hydrogel, Polyethylene Glycol Dimethacrylate/chemistry , Silver Sulfadiazine/chemistry , Silver/chemistry , Anti-Bacterial Agents/pharmacology , Hydrogel, Polyethylene Glycol Dimethacrylate/pharmacology , Silver/pharmacology , Silver Sulfadiazine/pharmacology , Staphylococcus aureus/drug effects
10.
Pharm Dev Technol ; 20(3): 306-13, 2015 May.
Article in English | MEDLINE | ID: mdl-24417644

ABSTRACT

CONTEXT: Drug polymorphism could affect drug product dissolution, manufacturability, stability and bioavailability/bioequivalence. The impact of polymorphism on the manufacturability and in vitro dissolution profiles of sulindac capsules has not been studied yet. OBJECTIVE: To evaluate the impact of polymorphism on the manufacturability and in vitro dissolution of sulindac hard gelatin capsules. MATERIALS AND METHODS: Sulindac crystal forms I and II (SLDI and SLDII, respectively) were prepared and characterized. Powder formulations containing one of the polymorphs, lactose and magnesium stearate (at three different levels) were prepared and their flow properties determined. Hard gelatin capsules were filled with the formulations and tested for fill-weight variations. Drug dissolution for SLDI- and SLDII-containing hard gelatin capsules was determined. RESULTS: Differences in flow properties for each polymorph were observed, as well as for their formulations, which in turn affected capsule weight homogeneity. Statistically significant differences in the rate and extent of drug release were observed between SLDI- and SLDII-containing capsules. DISCUSSION: Formulations containing SLDI showed a better manufacturability and a better dissolution profile than those with SLDII. CONCLUSION: Sulindac crystalline form I was the best candidate for hard gelatin capsule formulation because of its technological and in vitro dissolution properties.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/chemistry , Chemistry, Pharmaceutical/methods , Excipients/chemistry , Sulindac/chemistry , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Capsules , Crystallization , Drug Liberation , Gelatin , Lactose/chemistry , Powders , Solubility , Stearic Acids/chemistry , Sulindac/administration & dosage
11.
Eng. sanit. ambient ; Eng. sanit. ambient;18(2): 169-176, abr.-jun. 2013. tab
Article in Portuguese | LILACS | ID: lil-680747

ABSTRACT

Este estudo visa analisar a composição gravimétrica, avaliar parâmetros químicos e classificar os Resíduos de Construção Civil (RCC) da cidade de Fortaleza de acordo com a Resolução CONAMA nº 307 e com a NBR 10004. Os resultados indicam que o RCC de Fortaleza é composto por 93,40% do Grupo A, 6,40% do Grupo B, 0,02% do Grupo C e 0,20% Grupo D. O primeiro é composto principalmente por areia e solo (24,65%) e argamassa (22,00%), que são materiais com alto potencial de reutilização ou reciclagem. Além disso, de acordo com a análise química, o RCC de Fortaleza mostrou alta variabilidade em todos os parâmetros. Cr, Pb e SO4²-, por exemplo, apresentaram valores acima dos limites especificados pela NBR 10004, indicando que esse material deve ser classificado como Classe II-A (não perigoso e não inerte).


This study aims to analyze the gravimetric composition, evaluate chemical parameters and classify the construction waste (CW) of Fortaleza city according to CONAMA Resolution Nº 307 and to NBR 10004. Results show that Fortaleza's CW is composed by 93,40% of Group A, 6,40% Group B, 0,02% Group C and 0,2% Group D. The first is composed primarily by sand and gravel (24,65%) and mortar (22,00%), that are materials with high potential for reuse or recycling. Moreover, according to chemical analysis, Fortaleza's CW showed a high variability in all parameters. Cr, Pb and SO4²-, for example, showed above to the limits specified by NBR 10004, indicating that this material have to be classified as Class II-A (not dangerous and not inert).

12.
Ciênc. rural ; Ciênc. rural (Online);41(12): 2080-2083, Dec. 2011. tab
Article in Portuguese | LILACS | ID: lil-608067

ABSTRACT

A produção da nogueira-macadâmia é quantificada em "noz em casca" (casca e amêndoa). Assim, cultivares que possuam maior calibre detêm maior valor comercial. Sendo assim, o objetivo do presente trabalho foi realizar a análise de frutos e nozes de 22 cultivares de nogueira-macadâmia. As cultivares utilizados foram: 'África', 'Beaumont' (695), 'Cannon', 'C160', 'Doroti', 'Edson', 'Flor Rosa', 'HAES 722', 'HAES 814', 'HAES 816', 'HAES 842', 'HAES 849', 'IAC Campinas-B', 'IAC 9-20', 'IAC 9-20X', 'IAC 4-12B', 'Kau' ('HAES 344'), 'Keauhou' ('HAES 246'), 'Keaumi' ('IAC 4-20'), 'Mauka' ('HAES 741'), 'Pahala' ('HAES 788') e '791 Fuji'. Foram determinadas as dimensões (comprimento e diâmetro) e a massa fresca do carpelo, casca e amêndoa, além da massa fresca da "noz em casca" (casca e amêndoa), do TR (relação entre a massa das nozes em casca e a massa das amêndoas resgatadas). As cultivares apresentam diferenças quanto as dimensões dos frutos. A cultivar 'Edson' apresentou frutos e nozes com maiores dimensões e massa. Apenas as cultivares 'Pahala', 'Beaumont', 'IAC 9-20X' e 'Keaumi' apresentaram TR menor que 30 por cento.


The production of the macadamia walnut is measured in "nut in peel" (peel and almond). The cultivar that have higher caliber has greater commercial value. The objective of the present research was to analysis of fruits and nuts of 22 cultivars of macadamia walnut. The cultivars used were: 'África', 'Beaumont' (695), 'Cannon', 'C160', 'Doroti', 'Edson', 'Flor Rosa', 'HAES 722', 'HAES 814', 'HAES 816', 'HAES 842', 'HAES 849', 'IAC Campinas-B', 'IAC 9-20', 'IAC 9-20X', 'IAC 4-12B', 'Kau' ('HAES 344'), 'Keauhou' ('HAES 246'), 'Keaumi' ('IAC 4-20'), 'Mauka' ('HAES 741'), 'Pahala' ('HAES 788') and '791 Fuji'. It was determined the dimensions (length and diameter) and the fresh weight of the carpelo, peel and almond, besides the fresh weight of the "nut in peel" (peel and almond), besides TR (relationship among the weight of the nut in peel and the weight of the rescued almonds). The cultivars presented differences as the dimensions of the fruits. The cultivar 'Edson' presented fruits and nuts with larger dimensions and weight. The cultivars 'Pahala', 'Beaumont', 'IAC 9-20X' and 'Keaumi' presented TR lower than 30 percent.

13.
Ciênc. agrotec., (Impr.) ; 35(1): 35-44, jan.-fev. 2011. ilus, tab
Article in Portuguese | LILACS | ID: lil-576079

ABSTRACT

O sensoriamento remoto e o geoprocessamento são geotecnologias importantes no apoio ao levantamento de dados da agricultura, permitindo estudos e o entendimento das relações ambientais em que uma determinada cultura está inserida. Neste trabalho,objetivou-se, relacionar as variáveis físicas, como, altimetria, declividade e tipo de solo com o agrossistema cafeeiro existente no município de Umuarama-PR pelo uso de geotecnologias. Foi utilizada a imagem do satélite LANDSAT 5/TM (Thematic Mapper) com data de passagem em 02/07/2007 e o software SPRING 4.3.3. As bandas 3, 4 e 5 do sensor TM foram restauradas, resultando em imagens de 15 m de resolução espacial e, posteriormente, constituindo a composição colorida RGB, na sequência TM4, TM5, TM3, a qual foi empregada na identificação das lavouras cafeeiras por meio de interpretação visual. Para o estudo do relevo, foram utilizados dados da missão SRTM, os quais possibilitaram o conhecimento da altimetria e declividade da região. A imagem do sensor TM possibilitou a execução da classificação visual e consequente identificação das lavouras cafeeiras com alta precisão. Quanto ao relevo, verificou-se que aproximadamente 99 por cento das lavouras cafeeiras estão localizadas entre 380 e 480 metros de altitude e que 90 por cento destas estão situadas em declividades de até 8 por cento de inclinação. Em relação aos solos, observou-se que 89 por cento dos cafeeiros são cultivados sobre Latossolo Vermelho distrófico, de textura arenosa.


The remote sensing and geoprocessing are important geotechnologies in support of the survey data of agriculture, enabling studies and understanding of environmental relations in which a particular culture is insert. The objective of this work was to relate the physical variables, such as altimetry, slope and soil type with the coffee agrosystems in Umuarama-PR through the geotechnologies. The image of the LANDSAT 5/TM (Thematic Mapper) dated in 02/07/2007 and the software SPRING 4.3.3 were used for the image processing. The bands 3, 4 and 5 of the sensor TM were restored, which resulted in images of 15m spatial resolution and, later, creating the RGB color composition, which was used to identify the coffee crops through visual interpretation. For the relief map study, the data of the SRTM mission were applied, which enabled us to know the altimetry and declivity of the region. The image of the TM sensor enabled the visual classification and the consequent identification of the coffee crops with high precision. As for the relief area, it was noticed that about 99 percent of the coffee fields are located between 380 and 480 meters of altitude and that 90 percent of them are located in declivity of up to 8 percent of inclination. About the soils, it was observed that 89 percent of the coffee fields are grown over distrofic Red Latosol, of sandy texture.

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