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1.
J Biomater Appl ; 38(9): 1000-1009, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38456269

RESUMO

Morin is an antioxidant and anticancer flavonoid, extracted from natural sources, that may exert beneficial effects for several pathologies. Despite this, the administration of morin represents a challenge due to its low aqueous solubility. Mesoporous silica materials have emerged as biocompatible tools for drug delivery, as their pore size can be modulated for maximum surface area to volume ratio. In this contribution, we evaluate the ability of iron-modified mesoporous materials, for morin loading and controlled delivery. The SBA-15 and MCM-41 sieves were synthesized and modified with iron (metal content 4.02 and 6.27 % wt, respectivily). Characterization by transmission electron microscopy, XRD and UV-Vis revealed adequate pore size and agglomerates of very small metallic nanospecies (nanoclusters), without larger iron oxide nanoparticles. FT-IR spectra confirmed the presence of silanol groups in the solid hosts, which can interact with different groups present in morin molecules. SBA-15 materials were more efficient in terms of morin loading capacity (LC) due to their larger pore diameter. LC was more than 35% for SBA-15 materials when adsorptions studies were carried out with 9 mg of drug. Antioxidant activity were assayed by using DPPH test. Free iron materials presented a significate improvement as antioxidants after morin incorporation, reaching a scavenging activity of almost a 90%. On the other hand, in iron modified mesoporous materials, the presence of morin did not affect the scavenging activity. The results could be related with the formation of a complex between the flavonoid and the iron. Finally, biosafety studies using normal epithelial cells revealed that neither the loaded nor the unloaded materials exerted toxicity, even at doses of 1 mg/ml. These findings expand knowledge about mesoporous materials as suitable carriers of flavonoids with the aim of improving therapies for a wide range of pathologies.


Assuntos
Flavonas , Flavonoides , Neoplasias , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier , Flavonoides/química , Dióxido de Silício/química , Antioxidantes/química , Ferro , Porosidade
3.
Carbohydr Res ; 504: 108312, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33895608

RESUMO

Methanol dried over powdered 4 Å molecular sieves can be used for a selective mono-de-O-acetylation of the phenolic acetyl group of the per-O-acetyl protected brasilicardin A carbohydrate side chain. This reaction opens a practical procedure for a synthetic access to derivates of the immunosuppressive and cytotoxic natural product brasilicardin A.


Assuntos
Carboidratos , Acetilação , Processamento de Proteína Pós-Traducional
4.
Nanomaterials (Basel) ; 10(5)2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32443703

RESUMO

It is possible to take advantage of shallow reservoirs (<300 m) for CO2 capture and storage in the post-combustion process. This process is called enhanced carbon capture and storage (e-CCS). In this process, it is necessary to use a nano-modifying agent to improve the chemical-physical properties of geological media, which allows the performance of CO2 selective adsorption to be enhanced. Therefore, this study presents the development and evaluation of carbon sphere molecular nano-sieves (CSMNS) from cane molasses for e-CSS. This is the first report in the scientific literature on CSMNS, due to their size and structure. In this study, sandstone was used as geological media, and was functionalized using a nanofluid, which was composed of CNMNS dispersed in deionized water. Finally, CO2 or N2 streams were used for evaluating the adsorption process at different conditions of pressure and temperature. As the main result, the nanomaterial allowed a natural selectivity towards CO2, and the sandstone enhanced the adsorption capacity by an incremental factor of 730 at reservoir conditions (50 °C and 2.5 MPa) using a nanoparticle mass fraction of 20%. These nanofluids applied to a new concept of carbon capture and storage for shallow reservoirs present a novel landscape for the control of industrial CO2 emissions.

5.
Ci. Rural ; 49(4): e20180248, Apr. 11, 2019. tab
Artigo em Inglês | VETINDEX | ID: vti-19309

RESUMO

The use of larger seeds may improve the initial development, plant stand, and mass productivity in forage crops. The present study aimed to evaluate the effect of the size of seeds of Sudan grass (Sorghum sudanense L.), standardized on density, on parameters of physiological quality and crop productivity. Seeds were processed in a gravitational table in order to become uniform in terms of density and then submitted to sieves with apertures of 1.75 or 2.00 mm. Three different treatments (seeds without size classification, seeds with diameter between 1.75 mm and 1.99 mm, and seeds with diameter above 2.00 mm) were compared. This study consisted of a laboratory stage for the analysis of physiological variables of seed, and a stage in field plots under a randomized block design and 3 replicates. Larger seeds presented better physiological and productive performance and had a higher germination rate, seedling growth, and forage yield at the first cut. Both the sieve with opening of 1.75 mm and that of 2 mm were suitable for processing of seeds of this species.(AU)


O emprego de sementes maiores pode melhorar o desenvolvimento inicial, o estande de plantas e a produtividade de massa em cultivos forrageiros. Este trabalho visou avaliar o efeito do tamanho da semente de capim sudão (Sorghum sudanense L.), padronizada quanto à densidade, sobre parâmetros da qualidade fisiológica e de produtividade da cultura. As sementes foram processadas em mesa gravitacional, para serem uniformizadas em termos de densidade, e depois submetidas ou não a peneiras com abertura de 1,75 ou 2,00 mm. Assim, foram comparados três tratamentos (sementes sem classificação por tamanho; sementes com diâmetro entre 1,75 mm e 1,99 mm; e sementes com diâmetro acima de 2,00 mm). O trabalho consistiu de uma fase laboratorial, para análise de variáveis fisiológicas da semente, e uma fase em parcelas a campo, sob delineamento em blocos casualizados e três repetições. Sementes maiores apresentaram melhor desempenho fisiológico e produtivo, sendo superiores na taxa de germinação, crescimento de plântula e rendimento de forragem ao primeiro corte. Tanto a peneira com abertura de 1,75 mm quanto a de 2 mm mostraram-se adequadas para o processamento de sementes da espécie.(AU)

6.
Ciênc. rural (Online) ; 49(4): e20180248, 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1045338

RESUMO

ABSTRACT: The use of larger seeds may improve the initial development, plant stand, and mass productivity in forage crops. The present study aimed to evaluate the effect of the size of seeds of Sudan grass (Sorghum sudanense L.), standardized on density, on parameters of physiological quality and crop productivity. Seeds were processed in a gravitational table in order to become uniform in terms of density and then submitted to sieves with apertures of 1.75 or 2.00 mm. Three different treatments (seeds without size classification, seeds with diameter between 1.75 mm and 1.99 mm, and seeds with diameter above 2.00 mm) were compared. This study consisted of a laboratory stage for the analysis of physiological variables of seed, and a stage in field plots under a randomized block design and 3 replicates. Larger seeds presented better physiological and productive performance and had a higher germination rate, seedling growth, and forage yield at the first cut. Both the sieve with opening of 1.75 mm and that of 2 mm were suitable for processing of seeds of this species.


RESUMO: O emprego de sementes maiores pode melhorar o desenvolvimento inicial, o estande de plantas e a produtividade de massa em cultivos forrageiros. Este trabalho visou avaliar o efeito do tamanho da semente de capim sudão (Sorghum sudanense L.), padronizada quanto à densidade, sobre parâmetros da qualidade fisiológica e de produtividade da cultura. As sementes foram processadas em mesa gravitacional, para serem uniformizadas em termos de densidade, e depois submetidas ou não a peneiras com abertura de 1,75 ou 2,00 mm. Assim, foram comparados três tratamentos (sementes sem classificação por tamanho; sementes com diâmetro entre 1,75 mm e 1,99 mm; e sementes com diâmetro acima de 2,00 mm). O trabalho consistiu de uma fase laboratorial, para análise de variáveis fisiológicas da semente, e uma fase em parcelas a campo, sob delineamento em blocos casualizados e três repetições. Sementes maiores apresentaram melhor desempenho fisiológico e produtivo, sendo superiores na taxa de germinação, crescimento de plântula e rendimento de forragem ao primeiro corte. Tanto a peneira com abertura de 1,75 mm quanto a de 2 mm mostraram-se adequadas para o processamento de sementes da espécie.

7.
Zootaxa ; 4442(1): 137-152, 2018 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-30313987

RESUMO

Two new species of Hemimycale from Southeastern Brazil are described in this study with the use of morphological and molecular data. Hemimycale oxeata sp. nov. is orange salmon colored in life and has unique oxeote like tornote spicules in addition to the typical (subtylo-)strongyles of the genus. Hemimycale ceadensis sp. nov. is reddish orange in life and has raised, tiny pore sieves, and subtylostrongyles with asymmetrical ends and raphides as microscleres. The diagnosis of the genus Hemimycale was slightly modified for the inclusion of the new species. Maximum-Likelihood analyses of 18S rRNA and COI sequences resulted in the clustering of both new species with the type species of the genus, thus confirming our morphological identification. The value of anatomical characters of pore sieves for diagnosing species and the genus is discussed. A key for species identification is also furnished.


Assuntos
Poríferos , Animais , Brasil , RNA Ribossômico 18S
8.
Environ Technol ; 39(9): 1123-1132, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28425316

RESUMO

Modified versions of MCM-41 and SBA-15 were obtained from sucrose by carbon deposition. The ability of the resulting materials, MCM-41 CC and SBA-15 CC, to remove Rhodamine B from aqueous solutions was evaluated. TG/DTG, XRD, Nitrogen Adsorption (BET), and SEM were used to characterize the materials. Adsorption was investigated by finite bath studies. To characterize the adsorption behavior and mechanism, kinetics and equilibrium were assessed. MCM-41 CC provided the best adsorption results: adsorptive capacity of 11.91 mg of dye/g of material and 91.95% w/v dye removal (C0 = 50 mg L-1). The sucrose particles interacted well, to result in improved area and micropore volume. Hence, carbon deposition can afford materials with increased adsorptive capacity depending on the sieve employed during their preparation.


Assuntos
Rodaminas/química , Dióxido de Silício/química , Purificação da Água , Adsorção , Carbono
9.
Ultrason Sonochem ; 22: 89-94, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24844439

RESUMO

In this work, the combined use of ultrasound energy and molecular sieves was investigated for the synthesis of ethyl butyrate, ester with mango and banana notes, catalyzed by the immobilized lipase from Thermomyces lanuginosus (Lipozyme TL-IM). Initially, the best concentrations of biocatalysts (35%) and butyric acid (0.7M) were tested using ultrasound as an alternative to mechanical agitation. The amount of acid in the reaction could be increased by 2-fold when compared to previous works where mechanical agitation was used. In the next step, substrate molar ratio and reaction temperature were optimized and the best conditions were at their lowest levels: 1:1 (acid:alcohol), and 30°C, reaching 61% of conversion in 6h. Molecular sieves (3Å) were added to optimized reaction medium in order to remove the formed water and improve the maximum yield. The reaction yield increased 1.5 times, reaching 90% of conversion in 6h, when 60mg of molecular sieves per mmol of butyric acid was used. Finally, the reuse of Lipozyme TL-IM for the ultrasound-assisted synthesis of ethyl butyrate was verified for 10 batches, without any appreciable loss of activity, whereas in systems using mechanical agitation, the biocatalyst was completely inactivated after 5 batches. These results suggest that the combined use of ultrasound and molecular sieves greatly improve esterification reactions by stabilizing the enzyme and increasing yields.


Assuntos
Ascomicetos/enzimologia , Biocatálise , Butiratos/síntese química , Técnicas de Química Sintética/métodos , Enzimas Imobilizadas/metabolismo , Lipase/metabolismo , Ultrassom , Butiratos/química , Enzimas Imobilizadas/química , Esterificação , Resinas de Troca Iônica/química , Lipase/química , Temperatura
10.
Ciênc. rural (Online) ; 44(10): 1841-1844, Oct. 2014. tab
Artigo em Português | VETINDEX | ID: biblio-1479535

RESUMO

A farinha de peixe é um ingrediente muito utilizado na alimentação animal, apresenta um perfil ideal de aminoácidos essenciais, é rico em energia, ácidos graxos essenciais, vitaminas e minerais, com uma digestibilidade proteica acima de 80% para os camarões peneídeos. Na alimentação humana, está sendo estudada a utilização da farinha de pescado em salgadinhos, bolos, pães e bolachas. A adição enriquece a farinha com cálcio, fósforo, ferro, proteínas, e especialmente com ácidos graxos da série ômega 3. O eicosapentaenoico atua reduzindo riscos de doenças cardíacas e possuem ações antitrombóticas e anti-inflamatórias. O ácido docosahexaenoico e o araquidônico são fundamentais na formação de tecidos nervosos e na visão das crianças, além de serem necessários para gestantes. A farinha de resíduos de filetagem de peixes caracteriza-se por um alto conteúdo de matéria mineral, o que pode promover a eutrofização e comprometer a qualidade da água na aquicultura. O objetivo deste estudo foi avaliar a redução do conteúdo de fósforo nas farinhas de resíduo de peixe produzidas comercialmente por meio de peneiragem em diferentes malhas (0,60 - 1,00 -1,18 - 1,40 - 2,36 e 3,35mm). Foram realizadas coletas mensais de uma indústria de farinha de pescado por um período de 24 meses. As amostras foram fracionadas nas peneiras e a composição proximal das frações resultantes foi comparada com a farinha integral. A maior redução de fósforo total (32%) e cinzas (36%), além da maior elevação proteica (20%) ocorreram no fracionamento com a menor malha (0,60mm). A composição média do resíduo proveniente das peneiras foi de 47,04% de cinzas, 5,56% de fósforo total e 39,45% de proteína, indicando que o resíduo do fracionamento também pode ser comercializado como suplemento mineral e proteico.


Fish meal is widely included in animal feed because it contains ideal essential amino acids profile, it is rich in energy, essential fatty acids, vitamins and minerals and with >80% apparent protein digestibility in peneid shrimp. In human nutrition, studies are investigating the inclusion of fish meal in snacks, cakes, breads and cookies, as an enrichment in calcium, phosphorus, iron, protein and, especially, omega-3 fatty acids. Omega-3 fatty acids reduces heart diseases and have antithrombotic and anti-inflammatory properties (eicosapentaenoic acid), and are essential to the formation of brain tissue and retina in infants and are important during pregnancy and lactation (docosahexaenoic acid). Fish meal produced from fish waste is rich in minerals (phosphorus), which may cause eutrophication and impair water quality in aquaculture. The aim of this study was to reduce phosphorus content from commercial fish meal produced from waste by sifting (0.60 - 1.00 - 1.18 - 1.40 - 2.36 and 3.35mm mesh sizes). Fish meal samples were collected monthly for 24 months. Proximate composition of subsamples per mesh size was compared to the unsieved sample. Results indicate that sifting through a 0.60mm sieve total phosphorus and ash contents were reduced up to 32% and 36%, respectively, further to increase protein content up to 20%. Average composition of the subsamples was 47.04% ash, 5.56% of total phosphorus and 39.45% protein, suggesting that the residue of the fractionation may be marketed as a mineral and protein supplement.


Assuntos
Farinha de Peixe , Fósforo , Uso de Resíduos Sólidos
11.
Ci. Rural ; 44(10): 1841-1844, Oct. 2014. tab
Artigo em Português | VETINDEX | ID: vti-760425

RESUMO

A farinha de peixe é um ingrediente muito utilizado na alimentação animal, apresenta um perfil ideal de aminoácidos essenciais, é rico em energia, ácidos graxos essenciais, vitaminas e minerais, com uma digestibilidade proteica acima de 80% para os camarões peneídeos. Na alimentação humana, está sendo estudada a utilização da farinha de pescado em salgadinhos, bolos, pães e bolachas. A adição enriquece a farinha com cálcio, fósforo, ferro, proteínas, e especialmente com ácidos graxos da série ômega 3. O eicosapentaenoico atua reduzindo riscos de doenças cardíacas e possuem ações antitrombóticas e anti-inflamatórias. O ácido docosahexaenoico e o araquidônico são fundamentais na formação de tecidos nervosos e na visão das crianças, além de serem necessários para gestantes. A farinha de resíduos de filetagem de peixes caracteriza-se por um alto conteúdo de matéria mineral, o que pode promover a eutrofização e comprometer a qualidade da água na aquicultura. O objetivo deste estudo foi avaliar a redução do conteúdo de fósforo nas farinhas de resíduo de peixe produzidas comercialmente por meio de peneiragem em diferentes malhas (0,60 - 1,00 -1,18 - 1,40 - 2,36 e 3,35mm). Foram realizadas coletas mensais de uma indústria de farinha de pescado por um período de 24 meses. As amostras foram fracionadas nas peneiras e a composição proximal das frações resultantes foi comparada com a farinha integral. A maior redução de fósforo total (32%) e cinzas (36%), além da maior elevação proteica (20%) ocorreram no fracionamento com a menor malha (0,60mm). A composição média do resíduo proveniente das peneiras foi de 47,04% de cinzas, 5,56% de fósforo total e 39,45% de proteína, indicando que o resíduo do fracionamento também pode ser comercializado como suplemento mineral e proteico.(AU)


Fish meal is widely included in animal feed because it contains ideal essential amino acids profile, it is rich in energy, essential fatty acids, vitamins and minerals and with >80% apparent protein digestibility in peneid shrimp. In human nutrition, studies are investigating the inclusion of fish meal in snacks, cakes, breads and cookies, as an enrichment in calcium, phosphorus, iron, protein and, especially, omega-3 fatty acids. Omega-3 fatty acids reduces heart diseases and have antithrombotic and anti-inflammatory properties (eicosapentaenoic acid), and are essential to the formation of brain tissue and retina in infants and are important during pregnancy and lactation (docosahexaenoic acid). Fish meal produced from fish waste is rich in minerals (phosphorus), which may cause eutrophication and impair water quality in aquaculture. The aim of this study was to reduce phosphorus content from commercial fish meal produced from waste by sifting (0.60 - 1.00 - 1.18 - 1.40 - 2.36 and 3.35mm mesh sizes). Fish meal samples were collected monthly for 24 months. Proximate composition of subsamples per mesh size was compared to the unsieved sample. Results indicate that sifting through a 0.60mm sieve total phosphorus and ash contents were reduced up to 32% and 36%, respectively, further to increase protein content up to 20%. Average composition of the subsamples was 47.04% ash, 5.56% of total phosphorus and 39.45% protein, suggesting that the residue of the fractionation may be marketed as a mineral and protein supplement.(AU)


Assuntos
Fósforo , Uso de Resíduos Sólidos , Farinha de Peixe
12.
J Biochem Mol Toxicol ; 27(9): 445-50, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23798366

RESUMO

In the present study, we reported the efficient synthesis of 11 3-(pyrimidin-2-yl)-thiazolidinones in good yields using molecular sieve as the desiccant agent. In addition, we have evaluated the antioxidant capacity of the synthesized compounds by the 2,2-diphenyl-2-picrylhydrazyl hydrate (DPPH•) and the 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS(+•) ) radicals scavenging assay. Six compounds showed antioxidant activity towards DPPH• (EC50 between 16.13 and 49.94 µg/mL) and also demonstrated excellent activity regarding ABTS(+•) (TEAC: 10.32-53.52). These results showed that compounds 3-(pyrimidin-2-yl)-thiazolidinones may be easily synthesized by a less expensive procedure and could be a good starting point to the development of new antioxidant compounds.


Assuntos
Antioxidantes/química , Antioxidantes/síntese química , Pirimidinas/química , Tiazolidinas/química , Tiazolidinas/síntese química , Benzotiazóis/química , Sequestradores de Radicais Livres/química , Oxirredução , Ácidos Sulfônicos/química
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