Browsing by Subject "Enzyme"

Now showing 1 - 4 of 4
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    Biocatalytic transesterification of salmon oil in ionic liquid media to obtain concentrates of omega-3 polyunsaturated fatty acids
    (Springer, 2024-06) Fuster, M.G.; Moulefera, I.; García Montalbán, Mercedes; Víllora Cano, Gloria; Ingeniería Química
    In this study, a biphasic system combining oil and ionic liquid was utilized for lipase-catalyzed transesterifcation of salmon oil and alcohol to concentrate n-3 PUFAs, notably EPA and DHA. Various process variables, such as enzyme type, quantity, alcohol chain length, temperature, reactant proportions, and ionic liquid selection, were systematically assessed to optimize the process and enhance the yield of these valuable fatty acids. It was found that the Novozym 435 and Lipolase 100L Type EX emerged as the most efective enzymes. The impact of varying alcohol chain lengths (C1–C8) was examined, revealing that the Novozym 435 enzyme displayed its peak synthetic activity with 2-propanol. The results revealed a substantial increase in the overall activity during the transesterifcation reaction when employing ILs featuring hydrophobic cations and anions with low nucleophilicity. Specifcally, the [omim+][NTf2 −] ionic liquid exhibited the highest level of activity. This research holds promise for more efciently and sustainably obtaining concentrated n-3 PUFAs from fsh oil while reducing environmental impact relative to other existing concentration processes.
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    Byproducts from cassava industry: alternative substrates for cyclodextrin glycosyltransferase production by alkalophilic Bacillus trypoxylicola SM-02
    (Murcia: Servicio de Publicaciones de la Universidad de Murcia, 2020) Peixoto, Carine Mascena; Coelho, Sheila Lorena de Araújo; Cazetta, Marcia Luciana
    In the present work was studied the use of cassava peel flour (CPF), corn steep liquor (CSL), and cassava wastewater as substrates to produce cyclodextrin glycosyltransferase (CGTase) from a new alkalophilic isolate of Bacillus trypoxylicola SM-02 by submerged fermentation. The experiments were performed as a Central Composite Design 22 , totalizing 11 assays. An enzymatic activity of 352.53 U/mL was obtained using 1.5 g of CPF and 0.6 g of CSL. The optimum temperature and pH of CGTase was 55 °C and 8.0, respectively. The CGTase depicted a relative activity of more than 50% for 120 min at the optimum temperature. The only salt that positively influenced the CGTase activity was CaCl2. The results are indicative of a potential role of B. trypoxylicola SM-02 in the production of CGTase using residual substrates.
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    Influence of the operating conditions on lipase-catalysed synthesis of ricinoleic acid estolides in solvent-free systems
    (Elsevier, 2008-12-25) Bódalo, A.; Bastida Rodríguez, Josefa; Máximo, María Fuensanta; Montiel Morte, María Claudia; Murcia Almagro, María Dolores; Ortega Requena, Salvadora; Ingeniería Química
    In this work, the synthesis of ricinoleic acid estolides, also named polyricinoleic acid (PR), in two different solvent-free reaction systems, catalysed by immobilised Candida rugosa lipase is described. First, the esterification was performed in an open air jacketed batch reactor and the influence of amount of enzyme, temperature and initial water content was tested. The best results were obtained when 5 g of soaked immobilised derivative was used as biocatalyst, and the reaction was carried out at 40 °C. It was observed that environmental relative humidity plays an important role in the enzymatic synthesis of ricinoleic acid estolides and, given that this parameter takes on a wide range of values depending on the season, it is considered the main cause of the poor reproducibility achieved in the open air reactor. To solve this problem, the ricinoleic acid estolides were synthesised under controlled atmosphere in a vacuum reactor with dry air intake. The optimum drying time of 7 h was selected. In these conditions, PR with an acid value of 57.5 mg KOH/g was synthesised in 48 h of reaction and the results were entirely reproducible.
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    The generation of suspended cell wall material may limit the effect of ultrasound technology in some varietal wines
    (MDPI, 2024-04-24) Pérez Porras, Paula; Bautista Ortín, Ana Belén; Martínez-Lapuente, Leticia; Guadalupe, Zenaida; Ayestarán, Belén; Gómez Plaza, Encarna; Tecnología de Alimentos, Nutrición y Bromatología; Facultad de Veterinaria
    The disruptive effect exerted by high-power ultrasound on grape cell walls enhances phenolic extraction, improving chromatic characteristics during red wine maceration. However, short maceration times may, sometimes, hinder this enhancement, and this effect could be attributed to the suspended cell wall material formation facilitated by sonication. This suspended material, having a strong affinity for phenolic compounds, can lead to their precipitation and elimination during subsequent vinification stages and, consequently, a significant portion of extracted phenolic compounds may not contribute to the final phenolic composition of the wine, impacting its chromatic features. To demonstrate this effect, sonicated grapes of two different varieties were vinified with No modified process that eliminated part of this suspended material. Results confirm our hypothesis; that is, the lack of positive outcomes in some cases is due to phenolic compound adsorption on suspended material.