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1.
Sci Rep ; 9(1): 12819, 2019 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-31492935

RESUMEN

The present study refers to the use of an environmental pollutant generated during the removal of hexavalent chromium from aqueous media. This pollutant is a material with catalytic properties suitable for application in the oxidative degradation of problematic organic compounds. The material, initially used as an adsorbent, is a composite prepared by modifying the crystalline phases of iron oxides together with the chitosan (CT-FeCr). Chemical and morphological characterizations of the materials were performed using SEM analysis coupled with EDS, XRD and DSC. The CT-FeCr beads were used in the degradation of methylene blue dye (MB) and showed excellent degradation potential (93.6%). The presence of Cr on the surface of the catalyst was responsible for the increase in catalytic activity compared to the CT-Fe and pure magnetite materials. The product of the effluent treatment and the presence of the catalyst itself in the environment do not pose toxic effects. In addition, the CT-FeCr beads showed catalytic stability for several consecutive reaction cycles with possible technical and economic viability. The concept of "industrial symbiosis" may be applied to this technology, with that term relating to the reuse of a byproduct generated in one particular industrial sector by another as a raw material.

2.
Environ Sci Pollut Res Int ; 26(16): 15973-15988, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30963426

RESUMEN

In this study, the synthesis of iron oxide stabilized by chitosan was carried out for the application and optimization in the removal process of aqueous Cr(VI) by central composite design (CCD). The calculation of these effects allowed to know, quantitatively, the variables and the interaction between them that could affect the Cr(VI) removal process. It was also verified that the most favorable conditions for chromium removal were the following: pH 5.0, Cr(VI) concentration of 130 mg L-1, adsorbent mass of 5 mg, and Fe(II) content of 45% (w/w) in the CT-Fe beads. The adsorption kinetics performed under these conditions showed that the chitosan/iron hybrid composite is an adsorbent material with high chromium removal capacity (46.12 mg g-1). It was found that all variables were statistically significant. However, it was observed that the variable that most affected Cr(VI) removal was the pH of the solution, followed by the concentration of chromium ions in solution and the interaction between them. Therefore, the studied experimental conditions are efficient in chromium adsorption, besides the operational simplicity coming from statistical design. Theoretical calculations showed that the most stable chitosan was that with Fe(II) in the structure, that is, in the reaction mechanism, there is no competition of Fe(II) with Cr(III, VI) in the available sites of chitosan. Thus, the theoretical calculations show that the proposed Cr(VI) removal is effective.


Asunto(s)
Quitosano/química , Cromo/aislamiento & purificación , Compuestos Férricos/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Cromo/análisis , Cromo/química , Concentración de Iones de Hidrógeno , Cinética , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos
3.
Chem Biol Drug Des ; 92(1): 1333-1343, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29603906

RESUMEN

In this study, different phenolic extracts were obtained from the jaboticaba skin meal (JSM), whose phenolic compounds were characterized and their antibacterial activities were assessed. Moreover, the activity of lyophilized ethanolic extract of jaboticaba skin (EEJS) on wound healing was analyzed in rats. The JSM phenolic extracts were obtained in four ways: aqueous, methanolic, ethanolic, and acetone extracts. The phenolic compounds were characterized in these extracts by high-performance liquid chromatography, and their antibacterial activities were evaluated. The in vivo experiment was divided into four groups and received the following treatments: G1-silver sulfadiazine (positive control); G2-EEJS at 10%; G3-EEJS at 5%, and G4-EEJS at 2.5%. The aqueous extract did not inhibit the growing of any bacterium. The ethanolic, acetone, and methanolic extracts inhibited the growing of all bacteria tested at the concentrations of 1.25%, 2.50%, and 5.00%, respectively. The ethanolic extract was the one that showed the highest bacterial inhibition potential and the highest contents of phenolic compounds, especially of catechin, epicatechin gallate, and epicatechin. The G3 and G4 treatments presented faster wound healing compared to the G1 one, as it promoted a less intense inflammatory reaction and full closure of the wounds at an accelerated rate.


Asunto(s)
Antibacterianos/farmacología , Myrtaceae/química , Fenoles/química , Cicatrización de Heridas/efectos de los fármacos , Animales , Antocianinas/química , Antocianinas/aislamiento & purificación , Antocianinas/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Frutas/química , Frutas/metabolismo , Listeria monocytogenes/efectos de los fármacos , Masculino , Myrtaceae/metabolismo , Fenoles/aislamiento & purificación , Fenoles/farmacología , Extractos Vegetales/química , Ratas , Ratas Wistar , Piel/patología , Staphylococcus aureus/efectos de los fármacos
4.
J Biomol Struct Dyn ; 34(9): 1839-48, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26130457

RESUMEN

Water pollution is a significant and growing problem throughout the world, especially in developing countries. In order to minimize environmental problems, catalysts have increasingly been designed to remove pollutants from the water. In an attempt to innovate by the creation of new low-cost alternatives to efficiently remove pollutants, the enzymatic treatment has been intensely studied for this purpose. Reactions catalyzed by enzymes are able to perform specific treatments, commonly with high rates of the final products. With this, the enzyme, peroxidase, is a promising candidate as a bioremediation catalyst. The efficiency of oxidoreductive enzymes, such as horseradish peroxidase (HRP) and soybean peroxidase (SP) have been studied, given that their performance depends on the substrate. In this investigation, experimental techniques and theoretical calculations have been employed in order to investigate the oxidative process for the ferulic acid and bromophenol blue dyes, performed by HRP and SP. Both enzymes showed a comparable behavior with respect to ferulic acid substrate. On the other hand, by utilizing bromophenol blue dye as a substrate, the behavior of the employed catalysts was significantly different. Experimental data have shown that HRP was more active toward bromophenol blue when compared to ferulic acid, being more rapidly degraded by the HRP enzyme. This tendency was confirmed by our theoretical docking, PM6 semi-empirical method, and DFT calculation results, in which the interaction, binding energies, and transition states were determined.


Asunto(s)
Biodegradación Ambiental , Contaminantes Ambientales , Modelos Teóricos , Peroxidasas , Sitios de Unión , Azul de Bromofenol/química , Catálisis , Dominio Catalítico , Ácidos Cumáricos/química , Contaminantes Ambientales/química , Enlace de Hidrógeno , Cinética , Modelos Moleculares , Conformación Molecular , Simulación del Acoplamiento Molecular , Oxidación-Reducción , Peroxidasas/química , Peroxidasas/metabolismo , Unión Proteica , Especificidad por Sustrato
5.
Environ Technol ; 37(10): 1288-95, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26502790

RESUMEN

The use of oxidoredutive enzymes in removing organic pollutants has been the subject of much research. The oxidation of phenolic compounds in the presence of chemical additives has been the focus of this study. In this investigation, the influence of the additives polyethylene glycol and Triton X-100 was evaluated in the phenol oxidation, caffeic acid, chlorogenic acid and total phenolic compounds present in coffee processing wastewater (CPW) at different pH values, performed by turnip peroxidase and peroxidase extracted from soybean seed hulls. The influence of these additives was observed only in the oxidation of phenol and caffeic acid. In the oxidation of other studied phenolic compounds, the percentage of oxidation remained unchanged in the presence of these chemical additives. In the oxidation of CPW in the presence of additives, no change in the oxidation of phenolic compounds was observed. Although several studies show the importance of evaluating the influence of additives on the behaviour of enzymes, this study found a positive response from the economic point of view for the treatment of real wastewater, since the addition of these substances showed no influence on the oxidation of phenolic compounds, which makes the process less costly.


Asunto(s)
Brassica napus/enzimología , Glycine max/enzimología , Peroxidasas/metabolismo , Fenoles/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/análisis , Ácidos Cafeicos/aislamiento & purificación , Ácidos Cafeicos/metabolismo , Ácido Clorogénico/aislamiento & purificación , Ácido Clorogénico/metabolismo , Estabilidad de Enzimas/efectos de los fármacos , Residuos Industriales/análisis , Octoxinol/metabolismo , Oxidación-Reducción , Peroxidasas/aislamiento & purificación , Fenoles/metabolismo , Polietilenglicoles/metabolismo , Sustancias Protectoras/metabolismo , Purificación del Agua/métodos
6.
Braz. arch. biol. technol ; Braz. arch. biol. technol;58(4): 494-503, Jul-Aug/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-753943

RESUMEN

The aim of this study was to evaluate the therapeutic and toxicologic effects of the administration of the powered vegetable extract and aqueous extract of Tournefortia paniculata leaves on Wistar rats, subjected to a hypercaloric diet for 42 days. The rats were divided into five groups and were given the following treatments by gavage: T0 (control) - 1.0 mL water day-1; T1 - aqueous extract containing 14 mg phenolic compounds kg-1 rat day-1; T2 - 14 mg quercetin kg-1 rat day-1; T3 - 50 mg powered vegetable extract from T. paniculata leaves (PVE) kg-1 rat day-1 and T4 - 100 mg PVE kg-1 rat day-1. The treatments did not significantly alter the weight, but were effective in reducing liver fat, glucose and serum triglycerides. The treatment T1 reduced food consumption and lipid peroxidation. None of the treatments showed genotoxic potential. Results showed that T. paniculata leaves possessed an anti-obesity potential. However, a more detailed study of the medicinal potential and characterization of phytochemicals in this plant would be still necessary for a better understanding of its mechanisms of action, enabling future applications in the treatment of this pathology or for various therapeutic purposes.

7.
Biosci. j. (Online) ; 30(3 Supplement): 431-439, 2014. tab
Artículo en Portugués | LILACS | ID: biblio-947892

RESUMEN

Esse estudo teve como objetivo realizar a caracterização química das hortaliças não-convencionais conhecidas como ora-pro-nobis (Pereskia aculeata e Pereskia grandifolia). Foi determinada a composição centesimal e mineral, bem como os teores de vitamina C, carotenoides totais, -caroteno, licopeno, ácido oxálico, nitrato, saponinas, compostos fenólicos e o inibidor da tripsina da farinha das folhas destas plantas. P. grandifolia apresentou os maiores teores de proteínas e de lipídios e os menores de cinzas e fibra alimentar total, que P. aculeata. Já P. grandifolia apresentou maior teor de cálcio, e para os demais minerais a P. aculeata se destacou. A P. aculeata também apresentou os maiores teores de vitamina C e -caroteno. Quanto aos carotenoides totais e o ácido oxálico P. grandifolia apresentou maiores níveis, sendo que na P. aculeata não foi detectado o licopeno, mas os teores de nitratos foram 15 vezes superiores ao de P. grandifolia, apresentando também maior inibição da tripsina. Os teores de saponinas foram semelhantes nas duas amostras de farinhas analisadas. Conclui-se que as folhas destas cactáceas são importantes fontes de proteínas, fibras, minerais (principalmente o cálcio e o ferro) e de compostos bioativos. Mesmo sendo detectados antinutrientes nas farinhas, seu consumo diário não será suficiente para causar malefícios à saúde humana.


The aim of this study was to chemistry characterize the non-conventional vegetable known as ora-pro-nobis (Pereskia grandifolia and Pereskia aculeata). The proximate and mineral compositions were determined as well as vitamin C, total carotenoids, -carotene, lycopene, oxalic acid, nitrate, saponins, phenolic compounds and the trypsin inhibitor from flour produced from the leaves of these plants. P. grandifolia showed higher levels of proteins and lipids and lower ash and total dietary fiber than P. aculeata. The P. grandifolia showed greater calcium concentrations while P. aculeata presented higher concentrations of the other minerals. The P. aculeata also showed the highest levels of vitamin C and -carotene. Regarding total carotenoids and oxalic acid the P. grandifolia showed higher levels, while in P. aculeata lycopene was not detected, but nitrate levels were 15 times higher than in P grandifolia, also showing greater trypsin inhibition. The saponin contents were similar in the two flour samples analyzed. It was concluded that these plants are important sources of proteins, fibers, minerals (especially calcium and iron) and bioactive compounds. Although antinutrients were found in flour, it is suggested that these cacti can enrich the diet with nutrients, since daily intake does not present harm to human health.


Asunto(s)
Verduras , Alimentos
8.
Ciênc. rural ; Ciênc. rural (Online);43(12): 2291-2295, dez. 2013. tab
Artículo en Portugués | LILACS | ID: lil-691319

RESUMEN

O crescente interesse da população pela promoção da saúde vem despertando a atenção dos consumidores por alimentos ricos em antioxidantes, combinado com a praticidade do consumo de sucos de frutos processados. O presente trabalho objetivou quantificar e avaliar a capacidade antioxidante de compostos fenólicos e ácido ascórbico em frutas in natura e polpas congeladas. As frutas in natura e polpas congeladas obtidas na região de Lavras - MG foram submetidas à quantificação de compostos fenólicos e ácido ascórbico e os respectivos extratos acetônico-etanólico e acetônico-metanólico. Foram determinadas suas atividades antioxidantes pelos métodos radicalares DPPH e ABTS. O extrato acetônico-metanólico foi mais efetivo para extrair os compostos antioxidantes das amostras. Apenas as polpas congeladas de acerola apresentaram uma redução do teor de compostos fenólicos em relação ao fruto. Para o teor de ácido ascórbico, houve uma redução nas polpas congeladas de acerola e goiaba. As amostras de acerola apresentaram os maiores teores de compostos fenólicos, ácido ascórbico e atividade antioxidante em relação aos demais frutos analisados.


The growing public interest in health- promotion, has called the attention of consumers for foods rich in antioxidants, combined with the practicality of the consumption of processed fruit juices. Therefore, this study aimed to quantify and evaluate the antioxidant capacity of phenolic compounds and ascorbic acid in fruits "in natura" and frozen pulps. The fruits "in natura" and frozen pulps from region of Lavras-MG, underwent quantification of phenolic compounds, ascorbic acid and the corresponding extracts acetonic-ethanolic and acetonic-methanolic. Their antioxidant activities were evaluated by DPPH and ABTS radical methods. The extract acetonic-methanolic was more effective to extract the antioxidant compounds from samples. Only frozen acerola pulps showed lower content of phenolic compounds in relation to fruit. For ascorbic acid, there was a reduction in the frozen pulp of acerola and guava. Acerola samples showed higher content of phenolic compounds, ascorbic acid and antioxidant activity compared to other fruits analyzed.

9.
Ciênc. rural ; Ciênc. rural (Online);43(12): 2280-2284, dez. 2013. tab
Artículo en Portugués | LILACS | ID: lil-691324

RESUMEN

A atemoia é um fruto híbrido derivado do cruzamento entre a fruta-do-conde, mais conhecida como ata (Annona squamosa L.), com a cherimoia (Annona cherimola Mill.). Este trabalho foi realizado com o objetivo de caracterizar os constituintes químicos das frações casca, polpa e semente de atemoia Gefner. Os frutos adquiridos foram selecionados, pesados e medidos. Foram separados em casca, polpa, semente e eixo floral, que também foram pesados para determinar suas proporções. Para o restante dos frutos, foram separadas as frações em sete repetições de 13 frutos. Em seguida, as frações casca, polpa e sementes foram liofilizadas e armazenadas em freezer. Foi determinada a proporção das frações do fruto, a composição centesimal, o ácido ascórbico, os açúcares totais, os minerais e alguns compostos bioativos. A polpa representou cerca de 60% do peso do fruto, enquanto a casca 28,13% e as sementes 8,34%. O fruto apresentou, em média, 56 sementes, com diâmetro longitudinal de 10,79cm e diâmetro transversal de 26,64cm. Os maiores teores de proteína bruta, extrato etéreo e fibra alimentar foram encontrados nas sementes e casca. A casca se destacou nos teores de cinzas. A polpa apresentou os maiores teores de ácido ascórbico e açúcares totais em relação às outras frações. A ordem da composição de macronutrientes na casca, na polpa e nas sementes da atemoia foi K>P>Ca>Mg; para os micronutrientes na casca e nas sementes, foi Fe>Zn>Cu>Mn>S e, na polpa, foi Fe>Zn>Mn>Cu>S. A casca apresentou os níveis mais altos de inibidores de tripsina e atividade hemaglutinante. Os teores de compostos fenólicos foram relativamente baixos no fruto.


The atemoya is a hybrid fruit derived from the cross between the sugar apple (fruta-do-conde), better known as ata (Annona squamosa L.) with the cherimoya (Annona cherimola Mill.). The aim of this research was to characterize the chemical constituents of the fractions skin, pulp and seed of the hybrid fruit atemoya, variety Gefner. The fruits purchased and selected were weighed and measured. They were separated into skin, pulp, seed and floral axis which were also weighted to determine their proportions. For the rest of the fruits, the fractions were separated into 7 replicates of 13 fruits. Then, the fractions skin, pulp and seeds were freeze-dried and stored in freezer. The proportion of the fruit fractions, the centesimal composition, ascorbic acid, total sugars, minerals and some bioactive compounds were determined. The pulp represented about 60% of the fruit weight, while the skin 28.13% and the seeds 8.34%. The fruit presented on the average 56 seeds, with longitudinal diameter of 10.79 cm and transversal diameter of 26.64 cm. The largest contents of crude protein, ether extract and dietary fiber were found in both seeds and skin. The skin stood out in the ash contents. The pulp showed the highest contents of ascorbic acid and total sugars in relation to the other fractions. The order of the composition of macronutrients in the skin, pulp and seeds of the atemoya was K>P>Ca>Mg; for the skin and seed micronutrients were Fe>Zn>Cu>Mn>S and in the pulp were Fe>Zn>Mn>Cu>S. The skin presented the highest levels of trypsin inhibitors and hemagglutinating activity. The phenolic compounds were relatively low in the fruit.

10.
Ciênc. rural ; Ciênc. rural (Online);42(4): 751-756, abr. 2012. tab
Artículo en Portugués | LILACS | ID: lil-623074

RESUMEN

O objetivo deste trabalho foi avaliar a utilização de cactáceas do gênero Pereskia na alimentação humana. A pesquisa foi realizada nos 1.525 domicílios da cidade de São Gonçalo do Abaeté (MG). Nessa cidade, onde foi aplicado o questionário socioeconômico e quanto ao uso alimentar desta planta, comumente chamada de ora-pro-nóbis, somente 25 domicílios possuíam plantas do gênero Pereskia. Em 22 domicílios, havia a presença da Pereskia grandifolia, em três, havia a de Pereskia aculeata e, em um, havia os dois tipos. A presença de nutrientes na ora-pro-nobis foi citada por 83,33% dos entrevistados, sendo que 33,37% citaram um consumo mensal. A planta foi citada por 66,67% dos entrevistados como importante no tratamento da anemia ferropriva, por 16,67%, como agente terapêutico para o câncer, por 12,50%, para prevenção ou tratamento da osteoporose e, por 8,33%, para o tratamento da constipação intestinal. A classificação da ora-pro-nobis na categoria das hortaliças foi citada por 54,17% dos entrevistados. Concluiu-se que o resgate cultural do consumo desse tipo de planta poderá melhorar a condição nutricional e de renda das pessoas menos favorecidas economicamente, tanto no ambiente urbano quanto rural, de diferentes regiões do Brasil.


The objective of this study was to evaluate the use of cacti of the genus Pereskia, for human consumption food. The study was conducted in 1.525 households in the city of São Gonçalo do Abaeté (MG). In this city where the socioeconomic questionnaire was applied regarding the dietary use of this plant, commonly referred to as ora-pro-nobis, only 25 of the households possessed plants of the genus Pereskia. In 22 households there was the presence of Pereskia grandifolia, in three households there was Pereskia aculeata, and one had both types. The presence of nutrients in the ora-pro-nobis was cited by 83.33% of respondents, where 33.37% cited monthly consumption. The plant was cited by 66.67% of the respondents as important in the treatment of iron deficiency anemia, by 16.67% as a therapeutic agent for cancer, by 12.50% for prevention or treatment of osteoporosis and 8.33% for the treatment of constipation. ora-pro-nobis was classified as a vegetable by 54.17% of respondents. It was concluded that the cultural revival of consumption of this type of plant may improve nutritional status and income of lower-class families in both urban and rural regions, from different regions of Brazil.

11.
Water Sci Technol ; 65(4): 669-75, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22277225

RESUMEN

Peroxidases can be used in the decolorization process. There is a growing interest for new sources of this enzyme and for obtaining economically viable processes. In this work, a low-cost vegetable peroxidase extraction process is proposed; the resulting enzyme is characterized to determine its optimum pH, temperature, and stability conditions, and it is then applied in the decolorization of reactive dye Remazol Turquoise G 133%. The turnip peroxidase (TP) was utilized as an enzymatic source. This enzyme exhibited maximum activity at pH 7.0, and it was active in the temperature range of 30 to 50 °C, which favors its use in industrial processes. Acetone was the most efficient solvent to induce precipitation. The removal of Remazol Turquoise G 133% was 56.0% complete after 50 min, while 41.0% of the same dye was removed with the commercial horseradish peroxidase enzyme in 50 min. TP presents potential as a viable alternative in the decolorization of textile wastewaters.


Asunto(s)
Colorantes/metabolismo , Complejos de Coordinación/metabolismo , Indoles/metabolismo , Peroxidasas/metabolismo , Proteínas de Plantas/metabolismo , Contaminantes Químicos del Agua/metabolismo , Colorantes/química , Complejos de Coordinación/química , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Indoles/química , Residuos Industriales , Peroxidasas/química , Proteínas de Plantas/química , Industria Textil , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química
12.
Ciênc. rural ; Ciênc. rural (Online);42(1): 178-183, 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-612740

RESUMEN

Two distinct experiments were conducted simultaneously with phytases of Aspergillus oryzae and A. niger for determining enzyme activity in response to storage period (up to 180 days at room temperature - RT). In the first experiment, enzymes were stored as they were acquired (pure form) and the activity was measured periodically during 180 days of storage at RT. In the second experiment, the phytases were incorporated to a supplement containing vitamins, minerals, and amino acids; and then this supplement was stored at RT up to 180 days, so that every 30 days of storage was collected one aliquot from each replicate for determining enzymatic activity. In conclusion, the phytase activity is affected by storage duration. To ensure 80 percent of the initial activity, the phytases of A. oryzae and A. niger can be stored in the pure forms for up to 53 and 135 days at RT, respectively. However, if the phytases of A. oryzae and A. niger are incorporated to a supplement containing vitamins, minerals, and amino acids then the storage period at RT should not exceed 67 and 77 days, respectively.


Dois experimentos distintos foram realizados simultaneamente com fitases de Aspergillus oryzae e A. niger para a determinação da atividade enzimática em resposta ao período de armazenamento (por até 180 dias em temperatura ambiente - TA). No primeiro experimento, as enzimas foram armazenadas como adquiridas (forma pura) e a atividade foi determinada periodicamente durante 180 dias de armazenamento em TA. No segundo experimento, as fitases foram incorporadas a um suplemento contendo vitaminas, minerais e aminoácidos. Então este suplemento foi armazenado em TA por até 180 dias, de modo que, a cada 30 dias de armazenamento, uma alíquota de cada repetição foi coletada para a determinação da atividade enzimática. Conclui-se que a atividade da fitase é afetada pela duração do armazenamento. Para assegurar 80 por cento da atividade inicial, as fitases de A. oryzae e A. niger podem ser armazenadas nas formas pura por até 53 e 135 dias em TA, respectivamente. Entretanto, se as fitases de A. oryzae e A. niger são incorporadas a um suplemento contendo vitaminas, minerais e aminoácidos, o período de armazenamento em TA não deve exceder 67 e 77 dias, respectivamente.

13.
Ciênc. agrotec., (Impr.) ; 34(spe): 1617-1623, dez. 2010. ilus, tab
Artículo en Portugués | LILACS | ID: lil-573665

RESUMEN

A cenoura (Daucus carota L. ), planta da família das umbelíferas, produz uma raiz aromática e comestível, sendo uma das hortaliças mais cultivadas no Brasil. Representa a principal fonte de origem vegetal em carotenóides pró-vitamínicos A, especialmente o á e o β-caroteno, sendo, também, uma grande fonte de fibra dietética, antioxidantes e minerais. Conduziu-se este trabalho, com o objetivo de avaliar dois processos de extração de β-caroteno, fluído super crítico (EFS) e o convencional e analisar a composição centesimal da cenoura in natura. O teor de β-caroteno obtido pela extração por EFS e por convencional foi de 2.457 e 2.455 µg/100g, respectivamente. Os valores médios encontrados para a matéria-seca da cenoura foram de: matéria-seca = 8,9 por cento; extrato etéreo = 0,29 por cento; cinzas = 8,11 por cento; fibra bruta = 14,57 por cento, proteína bruta = 6,4 por cento, extrato não nitrogenado = 6,3 por cento e valor calórico = 27,7kcal. Conclui-se que a extração de carotenóides em cenoura pelo fluido supercritico é uma técnica de separação viável, pois este fluido é inerte, não deixa resíduo final e não gera resíduo ambiental. Pelos teores encontrados conclui-se também que as cenouras são boas fontes de fibras, apresentam alto teor de umidade e baixo teor de gorduras, cinzas e valor calórico.


The carrot (Daucus carota L.) is a plant of the Umbelliferae family. It produces an aromatic and edible root, and is one of the most widely cultivated vegetable in Brazil. It represents the main source of plant-origin, pro-vitamin A carotenoids, especially α and β-carotene, and is also a great source of dietary fiber, antioxidants and minerals. This study aimed to evaluate two methods of extraction of β-carotene, supercritical fluid (SFE) and conventional, and to examine the proximate composition of the carrot in nature. The contents of β-carotene obtained by SFE and by conventional extraction were 2,457 and 2,455 µg/100g, respectively. The average values found for the dry-matter of the carrot were: dry matter = 8.9 percent; ether extract = 0.29 percent; ashes = 8.11 percent, crude fiber = 14.57 percent, crude protein = 6,4 percent, non- nitrogen extract = 6.3 percent and caloric value = 27.7 kcal. It is concluded that the extraction of carotenoids using the supercritical fluid is a viable separation technique since this fluid is inert and does not generate waste or final environmental waste. It can be concluded from the levels found that carrots are good sources of fiber, present high moisture content and low fat, ash and calorific value.

14.
Ciênc. agrotec., (Impr.) ; 34(4): 914-921, July-Aug. 2010. ilus, tab
Artículo en Portugués | LILACS | ID: lil-556980

RESUMEN

A lichia (Litchi chinensis Sonn.) é um fruto subtropical de alto potencial comercial devido ao seu sabor levemente acidificado, excelente aroma, alto valor nutritivo e atrativa cor vermelha da casca. Ainda no campo, a cor da casca altera-se facilmente, tornando-se escurecida em resposta a estresses (alterações da umidade relativa e ataque de patógenos). Após colhida, a casca da lichia perde rapidamente sua cor vermelha. O escurecimento da casca tem sido atribuído a rápida degradação da antocianina, assim como: à rápida perda de umidade pelo fruto e à atividade de enzimas oxidativas como polifenoloxidases e peroxidases. Dada essa alta perecibilidade, o controle do escurecimento é fundamental para o aumento na vida útil pós-colheita, visando ao mercado interno e à exportação de frutas. Avaliou-se, neste trabalho, o comportamento pós-colheita de lichias da cv. Bengal quanto ao escurecimento da casca e às modificações relacionadas com a qualidade da polpa de lichias submetidas a diferentes embalagens: bandeja recoberta com filme de polietileno de baixa densidade com e sem perfurações e frutos recobertos com película de fécula de mandioca (3 por cento). Os frutos foram mantidos em temperatura ambiente (25,1ºC±1,5ºC; 69,3 por cento±8,62 por centoUR) e armazenados por seis dias. Foram realizadas análises físicas, químicas e bioquímicas no dia 0 e a cada 2 dias, até osexto dia de armazenamento. A embalagem recoberta com filme de polietileno perfurado apresentou-se eficiente na redução da perda de massa, escurecimento da casca e na manutenção do teor de antocianina da casca de lichias durante seis dias de armazenamento, em temperatura ambiente.


Lychee is a subtropical fruit of high commercial value, due to its slightly acid taste, excellent aroma, high nutritive value and attractive deep bright red color of its peel. Also in the field, skin color changes easily, becoming dark in response to stress (changes in relative humidity and the incidence of pathogens). Harvested lychee fruit rapidly loses its bright red skin colour. Peel browning of harvested lychee has largely been attributed to the rapid degradation of the anthocyanin pigments as well as the rapid loss of moisture from the fruit and the activity of oxidative enzymes such polyphenoloxidase and peroxidases. Due to it high perishability, browning control is a fundamental process to the increase of post-harvest useful life aiming the home market and fruit exportation. This study evaluated the postharvest behavior of Litchi cv. Bengal fruits regarding pericarp browning and changes on lychee fruits pulp quality when different packing is applied: plastic trays covered with parafilm or solely parafilm, and fruits covered with cassava starch film (3 percent). Lychee fruits were stored for six days at room temperature (25.1ºC±1.5; 69.3 percentUR). Physical, chemical and biochemical analyses were performed on day 0 and on every two days till the end of the storage period. The package covered with perforated polyethylene film was efficient in reducing weight loss, skin browning and maintenance of the anthocyanin content of the bark of leeches for six days of storage at room temperature.

15.
Ciênc. agrotec., (Impr.) ; 34(2): 361-366, mar.-abr. 2010. ilus
Artículo en Portugués | LILACS | ID: lil-546663

RESUMEN

Inibidores de tripsina representam uma estratégia de controle de insetos e, por isso, a identificação e caracterização desses inibidores são etapas muito importantes para que novas formas de controle de pragas sejam desenvolvidas. Os inibidores de tripsina atuam na digestão primária de proteínas e comprometem o processo digestivo por completo, reduzindo a disponibilidade de aminoácidos ao inseto. A incorporação de inibidores de tripsina na dieta de insetos-praga é uma forma de controle cuja eficácia foi verificada por diferentes autores. Este projeto foi conduzido a fim de se observar a eficiência de extratos de folhas de mamona na inibição "in vitro" de proteinases do tipo tripsina do bicho-mineiro do cafeeiro. Após testes realizados com os extratos de folhas de mamona não-fervidos e fervidos com e sem a adição de β-mercaptoetanol 0,2 por cento (v/v) e mediante precipitações com acetona, verificou-se que o inibidor é uma molécula termoresistente e não-protéica. Desta forma, iniciou-se um processo de purificação da molécula inibidora por meio de cromatografia de adsorção com posterior análise em espectrômetro de massas. Os resultados dos testes de inibição indicaram a presença de um inibidor de tripsina eficaz contra o bicho-mineiro do cafeeiro nos extratos de folhas de mamona capaz de inibir 2,48 + 0,15 UTI, o que representa aproximadamente 40 por cento de inibição. Em testes realizados com tripsina bovina observou-se que o extrato de folhas de mamona não apresenta poder de inibição sobre essa enzima.


Trypsin inhibitors stand for a strategy of insect control and, therefore, the identification and characterization of these inhibitors are very important steps for new forms of pest control to be developed. Trypsin inhibitors act in the primary digestion of proteins and endanger the digestive process wholly, reducing the availability of aminoacids to the insect. The incorporation of trypsin inhibitors in the diet of pest insects is a control form whose efficacy was verified by different authors. In order to observe the efficiency of castor bean leaf extracts in inhibiting trypsin-like enzymes of the coffee leaf miner, an experiment was carried out with the purpose of observing an "in vitro" inhibition phenomenon. The results of the trypsin inhibition tests with normal and boiled with and without β-mercaptoethanol 0.2 percent (v/v) castor bean leaf extracts and the results of the acetone precipitation process indicated that the inhibitor is a heat-resistant molecule and it is not a protein. This way, the purification process was made by adsorption chromatography with later analysis in mass spectrometer. The reached results indicated that the presence of a trypsin inhibitor of the coffee leaf miner in the castor bean leaf extracts is capable of inhibiting 2.48 + 0.15 UTI, which stands for about 40 percent of inhibition. Tests performed with bovine trypsin indicated that the castor bean leaf extract have no inhibiting power on this enzyme.

16.
Ciênc. agrotec., (Impr.) ; 34(2): 440-444, mar.-abr. 2010. ilus
Artículo en Portugués | LILACS | ID: lil-546672

RESUMEN

O mamão é um fruto climatérico cujas transformações resultantes do amadurecimento ocorrem rapidamente após a colheita do fruto fisiologicamente maduro, desencadeadas pela produção do etileno e aumento da taxa respiratória. Isso o caracteriza como um fruto bastante perecível após a colheita. Dada essa alta perecibilidade, o controle do amadurecimento é fundamental para o aumento na vida útil pós-colheita, visando ao mercado interno e à exportação de frutas. O composto 1-metilciclopropeno (1-MCP) vem sendo usado com a finalidade de controlar o amadurecimento de frutos, flores e hortaliças. Neste trabalho foi avaliada a ação do tratamento com 1-MCP, em diferentes tempos de exposição, em mamões armazenados em condições ambiente. Os frutos foram colhidos no estádio 1 de maturação e foram submetidos ao 1-MCP, na concentração de 270 nL/L, por um período de 0, 12, 18 e 24 horas e, em seguida, armazenados em condição ambiente (T 22±2°C/UR 77 por cento ±2 por cento), por 8 dias. Os frutos tratados com 1-MCP apresentaram maior firmeza, menores teores de pectina solúvel e menor atividade de enzima PME mostrando que o 1-MCP foi eficiente em retardar o amaciamento dos frutos no período estudado.


The papaya is a climateric fruit whose transformations resulting from ripening occur shortly after the picking of the physiologically ripe fruit, triggered by the production of ethylene and increased breathing rate. That makes it a quite perishable fruit after harvest. Given that perishability, ripening control is fundamental to increase post-harvest shelf life, both for internal consumption and exports. The compound 1-methylcyclopropene (1-MCP) has been used with the purpose of controlling the ripening of fruits, flowers and vegetables. In this work, the effect of the treatment with 1-MCP on papayas stored under room conditions was evaluated in different exposure periods. The fruits were picked at stage 1 of maturation and were submitted to 1-MCP, at the concentration of 270 nL/L, for a period of 0, 12, 18 and 24 hours, and then stored under room conditions (T 22±2°C/RH 77 percent ±2 percent) for 8 days. The 1-MCP-treated fruits showed increased firmness, lower contents of soluble pectin and less activity of PME enzyme, showing that 1-MCP was effective in delaying the softening of the fruits over the studied period.

17.
Ciênc. agrotec., (Impr.) ; 33(spe): 1871-1876, 2009. tab
Artículo en Portugués | LILACS | ID: lil-542338

RESUMEN

Os insetos possuem diferentes enzimas digestivas que catalisam as reações de hidrólise do alimento consumido e essas se diferenciam entre os insetos de acordo com suas dietas e estado fisiológico. Foram avaliadas as atividades de algumas enzimas digestivas da praga do cafeeiro - Leucoptera coffeella (Guérin-Mèneville & Perrottet, 1842) (Lepidoptera: Lyonetiidae) - popularmente conhecida como bicho-mineiro do cafeeiro, para o entendimento de seu processo digestivo. Lagartas do bicho-mineiro do cafeeiro foram coletadas em campo e em casa-de-vegetação. O extrato enzimático utilizado foi obtido pela maceração das lagartas em água (4ºC). Determinaram-se os pH's ótimos e as atividades das enzimas α e β-glicosidases, α-amilase, aminopeptidase, fosfatase alcalina, sacarase, trealase e tripsina, incubando o extrato enzimático do bicho-mineiro do cafeeiro com substratos específicos. A análise dos resultados sugere que o processo digestivo e o ambiente intestinal do bicho-mineiro do cafeeiro sejam similares com o dos demais lepidópteros encontrados na literatura.


Insects are fitted with different digestive enzymes that catalyses the food hydrolysis. Those enzymes differ from one insect to another according to their diets and physiological status. In this work, one intended to verify the activities of some digestive enzymes of the coffee leaf miner - Leucoptera coffeella (Guérin-Mèneville & Perrottet, 1842) (Lepidoptera: Lyonetiidae) - as a pre-requisite to understand its digest process, since this insect is a major plague in coffee production systems. Coffee leaf miner caterpillars were collected in fields and in greenhouse. The enzyme extract utilized in determining the enzyme activities was obtained through grinding the caterpillars in cold water. The optimum pH and the activities of the enzymes α and β-glucosidases, α-amylase, aminopeptidase, alkaline phosphatase, saccharase, trehalase and trypsin were measured by incubating the enzyme extract with specific substrates. The analysis of the optimum pH's indicated that the digestive process and intestinal environment of this insect are similar to another lepidopterans consulted in the literature.

18.
Ciênc. agrotec., (Impr.) ; 33(spe): 1953-1958, 2009. tab
Artículo en Portugués | LILACS | ID: lil-542351

RESUMEN

Objetivou-se, neste trabalho, avaliar as modificações da poligalacturonase (PG) e da pectinametilesterase (PME) em morangos cultivados na região de Lavras, MG, e armazenados em temperatura ambiente. Foram utilizados morangos das cultivares 'Oso-grande', 'Toyorrinho' e 'Tudla'. Utilizou-se o delineamento inteiramente casualizado com 4 repetições, sendo os tratamentos arranjados em esquema fatorial (3X2), sendo 3 cultivares e 2 dias de análises (0 e 5 dias). A parcela experimental foi constituída por 10 frutos. Durante o armazenamento houve uma diminuição nos teores de pectina total e um aumento nos de pectina solúvel em todas as variedades analisadas. A atividade da PG e PME aumentaram com o período de armazenamento, independente da cultivar.


The objective of this research was to evaluate the modifications of the polygalacturonase (PG) and the pectinmethilesterase (PME) in strawberries cultivated in the region of Lavras, MG, and stored at room temperature. Strawberries of the research were used for plantation of 'Oso-grande', 'Toyorrinho' and 'Tudla'. The entirely randomized design with 4 replicates was used, being the treatments arranged in factorial (3x2), being 3 plantations and 2 days of analyses (0 and 5 days). The experimental parcel was consisted by 10 fruits. During the storage there was a reduction in the levels of total pectin and an increase in the ones of soluble pectin in all the analyzed varieties. With the period of storage the PG and PME activity grew, independent of the cultivar.

19.
Arch. latinoam. nutr ; Arch. latinoam. nutr;58(4): 416-421, dic. 2008. tab
Artículo en Portugués | LILACS | ID: lil-588710

RESUMEN

A jabuticaba (Myrciaria cauliflora Berg) é uma fruta nativa brasileira e pouco se conhece sobre os constituintes químicos nas diversas partes do fruto, principalmente, em relação aos compostos bioativos. Este trabalho teve por objetivo determinar a composição centesimal e alguns compostos bioativos no fruto inteiro e nas frações da jabuticaba de duas variedades (Paulista e Sabará). O experimento foi conduzido em delineamento inteiramente casualizado em esquema fatorial 4 x 2 x 3, sendo 4 fatores, fruto inteiro, casca, polpa e semente; 2 variedades de jabuticabas e 3 repetições. Os frutos foram colhidos, selecionados, pesados, sanitizados, separados em fruto inteiro, casca, polpa e semente, que foram triturados, congelados e liofilizados até peso constante. Os teores de proteína bruta e extrato etéreo foram baixos. Os teores de cinzas não variaram entre as frações, exceto para as cascas da variedade Sabará que apresentaram os maiores teores. As fibras alimentares apresentaram diferença significativa entre as frações, não variando entre as duas variedades. As cascas apresentaram os maiores teores: 33,80 g/100g na Paulista e 33,23 g/100g na Sabará, sendo o maior percentual de fibras insolúveis. O maior teor de extrato não nitrogenado foi encontrado na polpa e o menor na casca, não se diferenciando entre as variedades. Quanto aos compostos bioativos, foram analisados saponinas, ácido oxálico, inibidor de tripsina, polifenóis e lectinas. Destes apenas os polifenóis nas frações casca apresentaram níveis elevados, necessitando de caracterizá-los, a fim de se verificar se o fruto é seguro para ser usado na indústria alimentícia.


Jabuticaba, Myrciaria cauliflora Berg, is a native Brazilian fruit; very little is known about the chemistry of its components, specially the bioactives compounds. The purpose of this paper was to determine the centesimal composition and some bioactives compounds of the whole fruit and fractions of two varieties of jabuticaba (Paulista and Sabará). The experiment was conducted in a completely randomized design on a 4 x 2 x 3 factorial scheme (4 factors: whole fruit, skin, pulp and seed; 2 varieties: Paulista e Sabará, and 3 replicates). The fruits were sampled, selected, weighted, sanitized and fractionated into whole fruit, skin, pulp and seed that were grinded, frozen and lyophilized to a constant weight. Protein contents and of ether extract were low for all fractions. The ash contents indicate elevated levels of minerals, specially on the Sabará variety. The content of alimentary fibers differed widely among fractions, with no differences between varieties. The skin fractions presented the highest levels of fiber, 33.80 g/100g on Paulista and 33.23 g/100g on Sabará, most of it was insoluble fibers. The greatest amount of non nitrogen extract was found in the pulp fraction, while the lowest was found in the skin, with no differences between varieties. Regarding bioactives compounds, only polyphenols were presented at considerable levels in all the fractions but the pulp one, showing the need for better characterization before using the fruit in the food industry.


Asunto(s)
Composición de Alimentos , Frutas/química
20.
Arch. latinoam. nutr ; Arch. latinoam. nutr;58(3): 309-315, sept. 2008. tab
Artículo en Español | LILACS | ID: lil-588726

RESUMEN

Los frutos maduros de tres especies de algarroba procedentes de Bolivia (Prosopis chilensis (Molina) Stunz, P. alba Grisebach y P. nigra (Grisebach) Hieronymus) y una de Brasil (P.juliflora (SW) DC) fueron estudiadas para determinar algunos factores nutricionales y antinutricionales. P. nigra presentó los niveles mas elevados de proteína bruta (11,33 g/100g materia seca-MS), cenizas (4,12 g /100g MS) y P. juliflora los menores niveles de lípidos (0,79 g /100g MS), proteína bruta (8,84g / 100g MS), fibra alimentaria (40,15 g/100g MS), el nivel más elevado de azúcares no reductores (52,51 g/100g MS) y la mayor digestibilidad* proteica in vitro (66,45 por ciento). La cantidad de inhibidor de tripsina (0,29 a 9,32 UTI / mg MS) fue inferior al de la soya cruda, en la cual la P. juliflora se destacó. Con relación a la saponina, hemaglutinina y polifenoles, los niveles encontrados son considerados bajos. Los niveles encontrados de nitrato son más elevados que los reportados en arvejas y frijoles, siendo la P. chilensis la que presentó el mayor valor (2,92g NO3- /kg MS). Los niveles de fitatos en las muestras variaron de 1,31 a 1,53 g/100 g MS.


The mature fruits of three species of algarroba found in Bolivia (Prosopis chilensis (Molina) Stunz, P. alba Grisebach y P. nigra (Grisebach) Hieronymus) and of one of Brazil (P. juliflora (SW) DC) were analysed for some nutritional and antinutritional factors. P. nigra showed the highest levels of crude protein (11.33 g/100g dry matter-DM) and ashes (4,12 g/100g DM). P. juliflora presented the lowest levels of lipids (0.79 g/100 g DM), crude protein (8.84 g/100 g DM) and dietary fiber (40.15 g/100g DM), and the highest levels of non reducing sugar (52.51 g/100 g DM) and in vitro protein digestibility (66.45 percent). Trypsin inhibitors concentration (0.29 to 9.32 UTI / mg DM) was inferior to that of raw soy; P. juliflora presented the higher values. Regarding saponin, hemagglutinin and poliphenol values, the levels found are considered low. As for nitrates, the levels found were higher than those reported for peas and beans, with P. chilensis presenting the highest value (2.92 g NO3-/kg DM). The levels of phytate varied from 1.31 a 1.53 g/100 g.


Asunto(s)
Eutrofización , Frutas/química , Harina/análisis , Prosopis/química , Análisis de los Alimentos
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