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1.
Membranes (Basel) ; 14(5)2024 May 14.
Article in English | MEDLINE | ID: mdl-38786947

ABSTRACT

The influence of storage stability and simulated gastrointestinal behavior of different extracts of guava leaves extracts (NC: not concentrated, and C10 and C20: concentrated by nanofiltration) was evaluated based on their total phenolic compound (TPC) contents and antioxidant activity as well as on their cytotoxic effects on A549 and Vero cells. The results showed that C10 and C20 presented high stability for 125 days probably due to their high TPC contents and antioxidant activity. The simulated gastrointestinal behavior modified their TPC contents; however, after all digestion steps, the TPC values were higher than 70%, which means that they were still available to exert their bioactivities. Additionally, the cytotoxic effects of these extracts were evaluated before and after the simulated gastrointestinal behavior or under different storage conditions. C10 presented the best selectivity indices (SI) values (IC50 Vero cells/IC50 A549 cells) at both conditions suggesting that it can be considered a potential extract to be developed as a functional food due to its resistance to the gastrointestinal digestion and storage conditions tested.

2.
Polymers (Basel) ; 15(20)2023 Oct 10.
Article in English | MEDLINE | ID: mdl-37896290

ABSTRACT

This review presents the advances in polymeric materials achieved by extrusion and injection molding from lignocellulosic agroindustrial biomass. Biomass, which is derived from agricultural and industrial waste, is a renewable and abundant feedstock that contains mainly cellulose, hemicellulose, and lignin. To improve the properties and functions of polymeric materials, cellulose is subjected to a variety of modifications. The most common modifications are surface modification, grafting, chemical procedures, and molecule chemical grafting. Injection molding and extrusion technologies are crucial in shaping and manufacturing polymer composites, with precise control over the process and material selection. Furthermore, injection molding involves four phases: plasticization, injection, cooling, and ejection, with a focus on energy efficiency. Fundamental aspects of an injection molding machine, such as the motor, hopper, heating units, nozzle, and clamping unit, are discussed. Extrusion technology, commonly used as a preliminary step to injection molding, presents challenges regarding fiber reinforcement and stress accumulation, while lignin-based polymeric materials are challenging due to their hydrophobicity. The diverse applications of these biodegradable materials include automotive industries, construction, food packaging, and various consumer goods. Polymeric materials are positioned to offer even bigger contributions to sustainable and eco-friendly solutions in the future, as research and development continues.

3.
Environ Technol ; 44(19): 2969-2982, 2023.
Article in English | MEDLINE | ID: mdl-35226584

ABSTRACT

In response to the intensification of eco-friendly routes as a strategy to access compounds of interest, extraction based on hydrothermal technologies is an efficient method to obtain high yields of compounds present in lignocellulosic materials. Accordingly, this study investigated the effects of the combination of ultrasonic pretreatments (energy density, 1.23 × 103-37.6 × 103 J/cm3; reaction time, 15 and 60 min) and subcritical water hydrolysis (SWH) (temperature, 220°C; flow rate, 10-30 mL/min; and reaction time, 0.5-15 min) on sugar yield profile from residual biomass of rice, soybean, and pecan. A characterization of the sugars present in the hydrolyzed solutions by high-performance liquid chromatography (HPLC) and a physicochemical evaluation of biomasses by Fourier-transform infrared spectroscopy (FT-IR) was performed. The highest yield reported were 23.8/100 g biomass, 14.4/100 g biomass, and 6.0/100 g biomass for pecan shell, rice shell, and soybean straw, respectively. Cellobiose, glucose, xylose, and arabinose were quantified by the HPLC, as well as inhibitors and organic acids. FT-IR indicated the compositions of the fresh and pretreated samples. Appropriately, the combined application of ultrasonic and SWH methods supported the valorization and optimization of high potential materials generated in agricultural processing.


Subject(s)
Ultrasonics , Water , Biomass , Hydrolysis , Water/chemistry , Spectroscopy, Fourier Transform Infrared
4.
Colloq. Agrar ; 19(1): 261-282, jan.-dez. 2023. mapas, ilus, tab, graf
Article in English | VETINDEX | ID: biblio-1509722

ABSTRACT

Water is one of the main limiting factors for achieving high productivity in agriculture. The hydric requirement of plants is fundamental for the dimensioning of the irrigation system and contributes to the better use of hydric resources. Moreover, the accurate computation of this element is essential for water management in agricultural systems. Nonetheless, due to the heterogeneity of different evapotranspiration estimation methods, the performance of its calculation can be considerably compromised. Accordingly, the aim of this study was to compare the methods for estimating reference evapotranspiration (ETo) by Benevides&Lopes, Camargo,Hargreaves&Samani, Jensen&Haise, Linacre, Makkink, Penman, Priestley&Taylor, Tanner&Pelton, and Turc, with the FAO-56 Penman-Monteith standard method, toevaluate the performance and accuracy of equational models. Furthermore, data from an automatic weather station belonging to the Brazilian National Institute of Meteorology(INMET), located in Palmeira das Missões, Rio Grande do Sul, Brazil, from January 1, 2020, to January 1, 2021, were used. Comparative statistical methods were utilizedto express the accuracy of the models and indicate the most appropriate equations for the conditions of the selected location. Cluster analysis and Principal Component Analysis (PCA) were applied. For Palmeira das Missões, the model proposed by Hargreaves&Samani indicated the best results and was characterized as the most appropriate alternative to estimate the ETo more accurately. The method indicated the most favorable results for R2(0.9890), d (0.9253), and r (0.9944). Furthermore, cluster and PCA analyses expressed the behavior of relationships between different mathematical models and meteorological parameters in relation to the ETo determination.(AU)


A água é um dos principais fatores limitantes para se atingir altas produtividades na agricultura. A necessidade hídrica da cultura é fundamental para o dimensionamento do sistema de irrigação e contribui para o melhor aproveitamento dos recursos hídricos. Desta forma, a computação acurada de tal elemento é essencial para o manejo da água em sistemas agrícolas. Entretanto, devido à heterogeneidade de diferentes métodos de estimativa da evapotranspiração, o desempenho de sua apuração pode ser consideravelmente comprometido. Adequadamente, o objetivo deste estudo foi comparar os métodos de estimativa da evapotranspiração de referência (ETo) de Benevides&Lopes, Camargo, Hargreaves&Samani, Jensen&Haise, Linacre, Makkink, Penman, Priestley&Taylor, Tanner&Pelton e Turc, com o método padrão FAO-56 Penman-Monteith, com o propósito de avaliar a performance e precisão dos modelos equacionais. Com isso, foram utilizados dados de uma estação meteorológica automática pertencente ao Instituto Nacional de Meteorologia (INMET), localizada em Palmeira das Missões, Rio Grande do Sul, Brazil, de 1 de janeiro de 2020 a 1 de janeiro de 2021. Métodos estatísticos comparativos foram utilizados para expressar a precisão dos modelos e indicar as equações mais apropriadas para as condições do local selecionado. A análise de agrupamento e Análise de Componentes Principais (PCA) foi aplicada. Para Palmeira das Missões, o modelo proposto por Hargreaves&Samani indicou os melhores resultados e se caracterizou como a alternativa mais apropriada para estimar a ETo da forma mais precisa. O método indicou os resultados mais favoráveis para R2(0,9890), d (0,9253) e r (0,9944). Ainda, as análises de agrupamento e PCA expressaram o comportamento de relações entre os diferentes modelos matemáticos e parâmetros meteorológicos em relação à determinação da ETo.(AU)


Subject(s)
Evapotranspiration , Agricultural Irrigation/methods , Conservation of Water Resources/methods , Brazil
5.
Membranes (Basel) ; 10(9)2020 Sep 18.
Article in English | MEDLINE | ID: mdl-32961881

ABSTRACT

The mussel-inspired method has been investigated to modify commercial ultrafiltration membranes to induce antifouling characteristics. Such features are essential to improve the feasibility of using membrane processes in protein recovery from waste streams, wastewater treatment, and reuse. However, some issues still need to be clarified, such as the influence of membrane pore size and the polymer concentration used in modifying the solution. The aim of the present work is to study a one-step deposition of dopamine (DA) and polyethyleneimine (PEI) on ultrafiltration membrane surfaces. The effects of different membrane molecular weight cut-offs (MWCO, 20, 30, and 50 kDa) and DA/PEI concentrations on membrane performance were assessed by surface characterization (FTIR, AFM, zeta potential, contact angle, protein adsorption) and permeation of protein solution. Results indicate that larger MWCO membranes (50 kDa) are most benefited by modification using DA and PEI. Moreover, PEI is primarily responsible for improving membrane performance in protein solution filtration. The membrane modified with 0.5:4.0 mg mL-1 (DA: PEI) presented a better performance in protein solution filtration, with only 15% of permeate flux drop after 2 h of filtration. The modified membrane can thus be potentially applied to the recovery of proteins from waste streams.

6.
Bioprocess Biosyst Eng ; 43(11): 1943-1949, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32474747

ABSTRACT

The objective of this work was to concentrate, through a membrane separation process, the fatty acids from oil/solvent mixture. The oil was obtained by ultrasound-assisted extraction from freeze-dried cells of Mortierella isabellina. The concentration of the fatty acids was investigated using flat-sheet polymer membranes of ultrafiltration and nanofiltration. The effects of temperature and pressure were evaluated by the retention of the fatty acids. Oil retentions between 45.23 and 58.20% to ultrafiltration membrane and 43.50 and 56.00% to nanofiltration membrane were observed. The best condition for the ultrafiltration membrane was 4 bar and 40 °C and for nanofiltration membrane was 12 bar and 50 °C. The oil contains a high concentration of oleic acid and palmitic acid that is a desirable property for the biodiesel production. The results showed the applicability of this technology in the solvent recovery step whereas the oil recovered contains a high concentration of fatty acids.


Subject(s)
Biofuels , Biotechnology/methods , Fatty Acids/isolation & purification , Industrial Microbiology/methods , Mortierella/metabolism , Equipment Design , Fatty Acids/analysis , Fatty Acids/chemistry , Fermentation , Freeze Drying , Membranes, Artificial , Oleic Acid , Polymers/chemistry , Pressure , Temperature , Time Factors , Ultrafiltration/methods , Ultrasonics
7.
Colloq. agrar. ; 15(4): 1-10, jul.-ago. 2019. tab, graf, ilus
Article in Portuguese | VETINDEX | ID: vti-22640

ABSTRACT

Frente a necessidade de preservação e a manutenção de materiais biológicos, dentre eles fungos com potencial para controle biológico, para o desenvolvimento biotecnológico e científico, que vêm ganhando destaque no cenário mundial. Sendo necessário a adequação de métodos de preservação que além de garantia a sobrevivência destes microrganismos permitam a conservação de suas características morfológicas, fisiológicas e genéticas, no entanto, não existe um método ideal ou universal para a conservação de materiais biológicos. Diante desta necessidade o presente trabalho teve como objetivo de avaliar a eficácia e viabilidade de três métodos de preservação de isolados do fungo Phomadimorpha (repicagens periódicas, Castellani e fragmentos de papel-filtro), em dois períodos de avaliação, seis e doze meses após o armazenamento. Estudou-se a eficácia e viabilidade, através do crescimento micelial do fungo em meio de cultivo contendo batata-dextrose-ágar. Houve variabilidade entre os métodos de preservação do isolado do fungo P. dimorpha para o crescimento micelial, eficácia do método e índice de velocidade do crescimento micelial, nos dois períodos de avaliação, após seis e doze meses de armazenamento. O método de preservação em fragmento de papel filtro mostrou-se como o mais eficaz na preservação do isolado do fungo P. dimorpha nos dois períodos de avaliação, após seis e doze meses de armazenamento, sendo ideal para obter o maior o crescimento micelial, eficácia do método e índice de velocidade do crescimento micelial.(AU)


Facing the need for preservation and maintenance of biological materials, among them fungi with potential for biological control, for biotechnological and scientific development, which are gaining prominence in the world scenario. It is necessary to adapt preservation methods that besides guaranteeing the survival of these microorganisms allow the conservation of their morphological, physiological and genetic characteristics, however, there is no ideal or universal method for the conservation of biological materials. In view of this need, the present work had the objective of evaluating the efficacy and feasibility of three methods for the preservation of Phoma dimorpha (periodic transfer, Castellani and filter paper fragments) isolates in two evaluation periods, six and twelve months after the storage. Efficacy and viability were studied by mycelial growth of the fungus in a culture medium containing potato-dextrose-agar. There was variability between the preservation methods of the P. dimorpha fungus isolate for mycelial growth, method efficacy and mycelial growth rate index, in the two evaluation periods, after six and twelve months of storage. The filter paper fragment preservation method was the most effective in reserving the P. dimorpha fungus isolate in the two evaluation periods, after six and twelve months of storage, being ideal to obtain the highest mycelial growth, efficacy of the method and mycelial growth rate index.(AU)


Subject(s)
Fungi/growth & development , Fungi/genetics , Fungi/physiology , Ascomycota/growth & development , Ascomycota/genetics , Ascomycota/physiology , Preservation, Biological/methods
8.
Colloq. Agrar ; 15(4): 1-10, jul.-ago. 2019. tab, graf, ilus
Article in Portuguese | VETINDEX | ID: biblio-1481505

ABSTRACT

Frente a necessidade de preservação e a manutenção de materiais biológicos, dentre eles fungos com potencial para controle biológico, para o desenvolvimento biotecnológico e científico, que vêm ganhando destaque no cenário mundial. Sendo necessário a adequação de métodos de preservação que além de garantia a sobrevivência destes microrganismos permitam a conservação de suas características morfológicas, fisiológicas e genéticas, no entanto, não existe um método ideal ou universal para a conservação de materiais biológicos. Diante desta necessidade o presente trabalho teve como objetivo de avaliar a eficácia e viabilidade de três métodos de preservação de isolados do fungo Phomadimorpha (repicagens periódicas, Castellani e fragmentos de papel-filtro), em dois períodos de avaliação, seis e doze meses após o armazenamento. Estudou-se a eficácia e viabilidade, através do crescimento micelial do fungo em meio de cultivo contendo batata-dextrose-ágar. Houve variabilidade entre os métodos de preservação do isolado do fungo P. dimorpha para o crescimento micelial, eficácia do método e índice de velocidade do crescimento micelial, nos dois períodos de avaliação, após seis e doze meses de armazenamento. O método de preservação em fragmento de papel filtro mostrou-se como o mais eficaz na preservação do isolado do fungo P. dimorpha nos dois períodos de avaliação, após seis e doze meses de armazenamento, sendo ideal para obter o maior o crescimento micelial, eficácia do método e índice de velocidade do crescimento micelial.


Facing the need for preservation and maintenance of biological materials, among them fungi with potential for biological control, for biotechnological and scientific development, which are gaining prominence in the world scenario. It is necessary to adapt preservation methods that besides guaranteeing the survival of these microorganisms allow the conservation of their morphological, physiological and genetic characteristics, however, there is no ideal or universal method for the conservation of biological materials. In view of this need, the present work had the objective of evaluating the efficacy and feasibility of three methods for the preservation of Phoma dimorpha (periodic transfer, Castellani and filter paper fragments) isolates in two evaluation periods, six and twelve months after the storage. Efficacy and viability were studied by mycelial growth of the fungus in a culture medium containing potato-dextrose-agar. There was variability between the preservation methods of the P. dimorpha fungus isolate for mycelial growth, method efficacy and mycelial growth rate index, in the two evaluation periods, after six and twelve months of storage. The filter paper fragment preservation method was the most effective in reserving the P. dimorpha fungus isolate in the two evaluation periods, after six and twelve months of storage, being ideal to obtain the highest mycelial growth, efficacy of the method and mycelial growth rate index.


Subject(s)
Ascomycota/growth & development , Ascomycota/physiology , Ascomycota/genetics , Fungi/growth & development , Fungi/physiology , Fungi/genetics , Preservation, Biological/methods
9.
Bioprocess Biosyst Eng ; 40(6): 843-855, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28236148

ABSTRACT

In this study, we developed a simplified method for producing, separating, and concentrating lipases derived from solid-state fermentation of agro-industrial residues by filamentous fungi. First, we used Aspergillus niger to produce lipases with hydrolytic activity. We analyzed the separation and concentration of enzymes using membrane separation processes. The sequential use of microfiltration and ultrafiltration processes made it possible to obtain concentrates with enzymatic activities much higher than those in the initial extract. The permeate flux was higher than 60 L/m2 h during microfiltration using 20- and 0.45-µm membranes and during ultrafiltration using 100- and 50-kDa membranes, where fouling was reversible during the filtration steps, thereby indicating that the fouling may be removed by cleaning processes. These results demonstrate the feasibility of lipase production using A. niger by solid-state fermentation of agro-industrial residues, followed by successive tangential filtration with membranes, which simplify the separation and concentration steps that are typically required in downstream processes.


Subject(s)
Aspergillus niger , Fermentation , Filtration , Lipase , Ultrafiltration
10.
Food Chem ; 141(4): 3954-9, 2013 Dec 15.
Article in English | MEDLINE | ID: mdl-23993571

ABSTRACT

In this work were extracted bioactive compounds from Brassica oleracea var capitata using supercritical CO2 and evaluated the antioxidant potential of the extracts. Five extractions were accomplished to investigate the influence of pressure (10-25 MPa) and temperature (20-60 °C) in the extraction yield, chemical composition and antioxidant potential towards peroxyl, superoxide and hydroxyl radicals. The highest extraction yield was obtained at 60 °C and 25 MPa, which was 0.47 wt% (run 2). In the characterisation of the extracts obtained was possible the identification of sulforaphane and iberin nitrile that present known biological properties. The extracts of all runs presented antioxidant activities towards the three radicals, but the highest activities for all radicals were using the extracts obtained in the run 2. The use of supercritical CO2 extraction to obtain bioactive compounds of B. oleracea var capitata showed to be a promising alternative to conventional extraction methods, since allowed the extraction of compounds with scientific and industrial interest.


Subject(s)
Antioxidants/chemistry , Antioxidants/isolation & purification , Brassica/chemistry , Chromatography, Supercritical Fluid/methods , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Reactive Oxygen Species/chemistry
11.
Ciênc. agrotec., (Impr.) ; 35(6): 1166-1171, Nov.-Dec. 2011. tab
Article in English | LILACS | ID: lil-610608

ABSTRACT

The adulteration of the product Ilex paraguariensis with other Ilex species is a mAjor problem for maté tea producers. In this work, three species of Ilex were evaluated for their volatile composition by headspace solid phase microextraction coupled to gas chromatography and mass spectrum detector (HS-SPME/GC-MS). The adulterating species I. dumnosa and I. theizans Mart. ex Reissek presented a different profile of volatile organic compounds when compared to I. paraguariensis. Aldehydes methyl-butanal, pentanal, hexanal, heptanal and nonanal were detected only in the adulterating species. This result suggests that such compounds are potential chemical markers for identification of adulteration and quality analysis of products based on Ilex paraguariensis.


A adulteração do produto Ilex paraguariensis com outras espécies de Ilex é um dos principais problemas dos produtores de erva-mate. Neste trabalho, três espécies de Ilex foram avaliadas quanto à sua composição volátil por microextração em fase sólida acoplada à cromatografia gasosa e detector de espectro de massas (HS-SPME/GC-MS). As espécies adulterantes I. dumnosa e I. theizans Mart. ex Reissek apresentaram um perfil diferente de compostos orgânicos voláteis, quando comparadas com a I. paraguariensis. Os aldeídos metil-butanal, pentanal, hexanal, heptanal e nonanal foram detectados apenas nas espécies adulterantes. Esse resultado sugere que esses compostos químicos são marcadores potenciais para a identificação de adulteração e análise da qualidade dos produtos à base de Ilex paraguariensis.

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