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1.
Sci Rep ; 14(1): 16027, 2024 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992035

RESUMO

Pfaffia glomerata (Spreng.) Pedersen has among its main bioactive compounds saponins, with the phytoestroid ß-ecdysone as its chemical marker. In this study, pressurized liquid extraction (PLE), a green extraction technique used to obtain bioactive compounds from plants, was employed to extract beta-ecdysone from P. glomerata leaves, stems, and roots. The 22 factorial design was used with the variables temperature (333 K and 353 K) and flow rate (1.5 and 2 mL min-1), pressure (300 Bar), time (60 min), and solvent [ethanol and distilled water (70:30 (v/v)] were kept constant for all parts of the plant. The results of experimental responses demonstrated that the factors temperature and flow rate significantly interfere with the yields of leaf (0.499%), root (0.65%) and stem (0.764%) extracts. The latter presented presents the highest yield compared to the other parts of the plant. HPLC results showed the presence of beta-ecdysone in all parts of the plant with concentrations of ß-ecdysone 86.82, 76.53 and 195.86 mg L-1 to leaf, root and stem, respectively. FT Raman results exhibited typical peaks of beta-ecdysone, such as 3310 cm-1, 1654 cm-1, and 1073 cm-1 for all plant parts. Another interesting result was the presence of the peak at 1460 cm-1 in the PLE root extract can be associated with selenium. This foundational knowledge confirms that the PLE extraction process was efficient in obtaining the chemical marker of Pfaffia glomerata in all plant parts.


Assuntos
Extratos Vegetais , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/química , Extratos Vegetais/análise , Raízes de Plantas/química , Folhas de Planta/química , Extração Líquido-Líquido/métodos , Caules de Planta/química , Pressão , Temperatura , Amaranthaceae/química
2.
Sci Rep ; 12(1): 19493, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376535

RESUMO

The worldwide loudspeaker market follows the growing tendency of electronic entertainment technologies both in quantity and variety. Consequently, the environmental impacts caused during the life cycle of loudspeakers increase in the same proportion, going in the opposite direction to what is determined by world environmental laws and regulations and global market tendencies. Even so, the environmental performance of this type of product is not considered in the decision-making process for technological updates in loudspeaker design. In this sense, Ecodesign is the most adequate Life Cycle Engineering tool applied in the design of a product since the environmental performance is considered throughout the different design stages. However, the feasibility of Ecodesign in products requiring complex production chains relies on splitting the product into subsystems and components. Thus, the present work focuses on evaluating the environmental performance of a classic loudspeaker motor, which is composed of a magnet, coil, and coil former. Eight raw material substitution scenarios are proposed and analyzed, which allowed the proposal identification with the best environmental performance within the current technologies. This represents an initial step toward the complete Ecodesign of a loudspeaker and sets the procedure to be followed with the other constitutive parts.


Assuntos
Meio Ambiente
3.
Appl Biochem Biotechnol ; 172(1): 263-74, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24078188

RESUMO

The use of lipases in industrial processes can result in products with high levels of purity and at the same time reduce pollutant generation and improve both selectivity and yields. In this work, lipase from Thermomyces lanuginosus was immobilized using two different techniques. The first involves the hydrolysis/polycondensation of a silica precursor (tetramethoxysilane (TMOS)) at neutral pH and ambient temperature, and the second one uses tetraethoxysilane (TEOS) as the silica precursor, involving the hydrolysis and polycondensation of the alkoxide in appropriate solvents. After immobilization, the enzymatic preparations were dried using the aerogel and xerogel techniques and then characterized in terms of their hydrolytic activities using a titrimetric method with olive oil and by the formation of 2-phenylethyl acetate in a transesterification reaction. The morphological properties of the materials were characterized using scanning electron microscopy, measurements of the surface area and pore size and volume, thermogravimetric analysis, and exploratory differential calorimetry. The results of the work indicate that the use of different silica precursors (TEOS or TMOS) and different drying techniques (aerogel or xerogel) can significantly affect the properties of the resulting biocatalyst. Drying with supercritical CO2 provided higher enzymatic activities and pore sizes and was therefore preferable to drying, using the xerogel technique. Thermogravimetric analysis and differential scanning calorimetry analyses revealed differences in behavior between the two biocatalyst preparations due to the compounds present.


Assuntos
Ascomicetos/enzimologia , Biocatálise , Dessecação , Lipase/química , Lipase/metabolismo , Silanos/química , Dióxido de Silício/química , Enzimas Imobilizadas , Esterificação , Géis , Concentração de Íons de Hidrogênio , Hidrólise , Solventes/química , Temperatura
4.
Ultrason Sonochem ; 20(4): 1002-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23402907

RESUMO

Diacylglycerol (DAG) rich oils have an organoleptic property like that of regular edible oils, but these oils do not tend to be accumulated as fat. Palm oil ranks first in the world in terms of edible oil production owing to its low cost. The aim of this study was to propose a new methodology to produce diacylglycerol by hydrolysis of palm oil using Lipozyme RM IM commercial lipase as a catalyst under ultrasound irradiation. The reactions were carried out at 55 °C with two different methods. First, the reaction system was exposed to ultrasonic waves for the whole reaction time, which led to enzymatic inactivation and water evaporation. Ultrasound was then used to promote emulsification of the water/oil system before the hydrolysis reaction, avoiding contact between the probe and the enzymes. An experimental design was used to optimize the ultrasound-related parameters and maximize the hydrolysis rate, and in these conditions, with a change in equilibrium, DAG production was evaluated. Better reaction conditions were achieved for the second method: 11.20 wt.% (water+oil mass) water content, 1.36 wt.% (water+oil mass) enzyme load, 12 h of reaction time, 1.2 min and 200 W of exposure to ultrasound. In these conditions diacylglycerol yield was 34.17 wt.%.


Assuntos
Diglicerídeos/biossíntese , Lipase/metabolismo , Óleos de Plantas/metabolismo , Sonicação , Biocatálise , Diglicerídeos/química , Hidrólise , Óleo de Palmeira , Óleos de Plantas/química
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