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1.
Int J Biol Macromol ; 264(Pt 2): 130730, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38462111

RESUMEN

Magnetic nanoparticles were functionalized with polyethylenimine (PEI) and activated with epoxy. This support was used to immobilize Lipase (Eversa® Transform 2.0) (EVS), optimization using the Taguchi method. XRF, SEM, TEM, XRD, FTIR, TGA, and VSM performed the characterizations. The optimal conditions were immobilization yield (I.Y.) of 95.04 ± 0.79 %, time of 15 h, ionic load of 95 mM, protein load of 5 mg/g, and temperature of 25 °C. The maximum loading capacity was 25 mg/g, and its stability in 60 days of storage showed a negligible loss of only 9.53 % of its activity. The biocatalyst demonstrated better stability at varying temperatures than free EVS, maintaining 28 % of its activity at 70 °C. It was feasible to esterify free fatty acids (FFA) from babassu oil with the best reaction of 97.91 % and ten cycles having an efficiency above 50 %. The esterification of produced biolubricant was confirmed by NMR, and it displayed kinematic viscosity and density of 6.052 mm2/s and 0.832 g/cm3, respectively, at 40 °C. The in-silico study showed a binding affinity of -5.8 kcal/mol between EVS and oleic acid, suggesting a stable substrate-lipase combination suitable for esterification.


Asunto(s)
Lipasa , Nanopartículas de Magnetita , Lipasa/química , Enzimas Inmovilizadas/química , Aceites de Plantas/química , Esterificación , Estabilidad de Enzimas
2.
J Biotechnol ; 379: 78-86, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38072327

RESUMEN

This study presents a solvent-free enzymatic approach for the synthesis of fatty acid methyl esters (FAMEs), such as methyl oleate, for their application as adjuvant in plant protection products (PPP) formulations. The direct esterification between free fatty acid and methanol was optimized to achieve 98% acid conversion. The kinetics of this conversion was accurately described by a simple second order mechanism and non-linear regression was applied to calculate the rate constants of the forward and backward reactions based on full progress curves data. The rate constant of the forward reaction (synthesis) was one order of magnitude higher than the backward reaction (hydrolysis) and favored formation of the target methyl ester product, rendering the removal of water unnecessary. Enzymatically synthesized methyl oleate was benchmarked against the chemically synthesized compound, showing matching results in terms of stability, spreadability and emulsifying capacity in plant care formulations. The enzymatic synthesis of FAMEs under solvent free conditions allows to achieve a safer and more sustainable character for carrier solvents in PPP formulations.


Asunto(s)
Ésteres , Lipasa , Lipasa/química , Esterificación , Hidrólisis , Ácidos Grasos , Solventes/química , Cinética , Enzimas Inmovilizadas/química
3.
J Oleo Sci ; 72(8): 799-810, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37468271

RESUMEN

This study aimed to produce stable plastic fat with desired physicochemical characteristics and ω-6/ω-3 fatty acid ratio (1:1-4:1) from palm stearin (PS), flaxseed oil (FSO) and cottonseed stearin (CS) via enzymatic interesterification (EIE). For the first time, the EIE variables of the blends containing PS, FSO and CS were investigated and optimized through single-factor experiments and response surface design to achieve a high interesterification degree. The optimized enzymatic interesterification conditions were: 60°C, 6 wt% Lipase UM1, and 6 h. Lipase UM1 had a similar effect on ID values with commercial lipases. The EIE improved the compatibility of the lipid blends, with the interesterified product EIE-721 (7:2:1, PS: FSO:CS) being the best candidate base stock for shortening considering its solid fat content, desired ω-6/ω-3 fatty acid ratio, wide melting range, abundant ß' form crystal, and compact microstructure. This study provides a strategy to produce balanced ω-6/ω-3 fatty acid plastic fat through enzymatic interesterification and validates the application of Lipase UM1 in the preparation of plastic fat.


Asunto(s)
Ácidos Grasos Omega-3 , Aceite de Linaza , Aceites de Plantas/química , Aceite de Semillas de Algodón , Ácidos Grasos/química , Lipasa/química , Esterificación , Aceite de Palma
4.
Bioprocess Biosyst Eng ; 46(8): 1195-1208, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37329348

RESUMEN

Acidified oil is obtained from by-product of crops oil refining industry, which is considered as a low-cost material for fatty acid production. Hydrolysis of acidified oil by lipase catalysis for producing fatty acid is a sustainable and efficient bioprocess that is an alternative of continuous countercurrent hydrolysis. In this study, lipase from Candida rugosa (CRL) was immobilized on magnetic Fe3O4@SiO2 via covalent binding strategy for highly efficient hydrolysis of acidified soybean oil. FTIR, XRD, SEM and VSM were used to characterize the immobilized lipase (Fe3O4@SiO2-CRL). The enzyme properties of the Fe3O4@SiO2-CRL were determined. Fe3O4@SiO2-CRL was used to catalyze the hydrolysis of acidified soybean oil to produce fatty acids. Catalytic reaction conditions were studied, including amount of catalyst, reaction time, and water/oil ratio. The results of optimization indicated that the hydrolysis rate reached 98% under 10 wt.% (oil) of catalyst, 3:1 (v/v) of water/oil ratio, and 313 K after 12 h. After 5 cycles, the hydrolysis activity of Fe3O4@SiO2-CRL remained 55%. Preparation of fatty acids from high-acid-value by-products through biosystem shows great industrial potential.


Asunto(s)
Ácidos Grasos , Lipasa , Lipasa/química , Hidrólisis , Aceite de Soja , Dióxido de Silicio , Enzimas Inmovilizadas/química , Agua , Estabilidad de Enzimas
5.
Int J Biol Macromol ; 242(Pt 2): 124807, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37178887

RESUMEN

The hydrolysis of natural oils (vegetable oils and fats) by lipase has significant applications in food and medicine. However, free lipases are usually sensitive to temperature, pH and chemical reagents in aqueous solutions, which hinders their widespread industrial application. Excitingly, immobilized lipases have been widely reported to overcome these problems. Herein, inspired by lipase interface activation, a hydrophobic Zr-MOF (UiO-66-NH2-OA) with oleic acid was synthesized for the first time in an emulsion consisting of oleic acid and water, and the Aspergillus oryzae lipase (AOL) was immobilized onto the UiO-66-NH2-OA through hydrophobic interaction and electrostatic interaction to obtain immobilized lipase (AOL/UiO-66-NH2-OA). 1H NMR and FT-IR data indicated that oleic acid was conjugated with the 2-amino-1,4-benzene dicarboxylate (BDC-NH2) by amidation reaction. As a result, the Vmax and Kcat values of AOL/UiO-66-NH2-OA were 179.61 µM﹒min-1 and 8.27 s-1, which were 8.56 and 12.92 times higher than those of the free enzyme, respectively, due to the interfacial activation. After treated at 70 °C for 120 min, the immobilized lipase maintained 52 % of its original activity, but free AOL only retained 15 %. Significantly, the yield of fatty acids by the immobilized lipase reached 98.3 % and still exceeded 82 % after seven times of recycling.


Asunto(s)
Lipasa , Ácido Oléico , Lipasa/química , Hidrólisis , Espectroscopía Infrarroja por Transformada de Fourier , Enzimas Inmovilizadas/química , Aceites de Plantas/química , Ácidos Grasos Insaturados , Agua , Interacciones Hidrofóbicas e Hidrofílicas
6.
Food Chem ; 412: 135558, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-36716631

RESUMEN

Palm olein (POL) was modified by enzymatic interesterification with different degrees of acyl migration in a solvent-free packed bed reactor. The fatty acid and acylglycerol composition, isomer content, thermodynamic behavior, and relationship between crystal polymorphism, solid fat content (SFC), crystal microstructure, and texture before and after modification were studied. We found that the increase in sn-2 saturation interesterification was not only due to the generated tripalmitin (PPP) but also caused by acyl migration, and the SFC profiles were changed accordingly. The emergence of high melting point acylglycerols was an important factor accelerating the crystallization rate, further shortening the crystallization induction time, leading to the formation of large crystal spherulites, thereby reducing the hardness. The transformation from the ß' to the ß form occurred during post-hardening during storage. The isomer content also affected the physicochemical properties of the modified POL.


Asunto(s)
Lipasa , Aceites de Plantas , Aceite de Palma/química , Aceites de Plantas/química , Lipasa/química , Ácidos Grasos/química , Triglicéridos/química , Glicéridos/química , Catálisis
7.
J Sci Food Agric ; 103(1): 108-117, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-35810339

RESUMEN

BACKGROUND: Diacylglycerol (DAG)-enriched oil has been attracting attention because of its nutritional benefits and biological functions, although the composition of its various free fatty acids (FFAs) and an unclear relationship between substrate and yield make it difficult to be identified and qualified with respect to its production. In the present study, linoleic acid-enriched diacylglycerol (LA-DAG) was synthesized and enriched from Camellia oil by the esterification process using the combi-lipase Lipozyme TL IM/RM IM system. RESULTS: The relationship between FFA composition and DAG species productivity was revealed. The results showed that heterogeneous FFA with a major constituent (more than 50%) exhibited higher DAG productivity and inhibited triacylglycerol productivity compared to homogeneous constituents. Joint characterization by high-performance liquid chromatography-evaporative light scattering detection, gas chromatography-mass spectrometry and ultra-performance liquid chromatography-heated electrospray ionization-tandem mass spectrometry identified that DAG components contained dilinoleic acid acyl glyceride, linoleyl-oleyl glyceride and dioleic acid acyl glyceride in esterification products. Under the optimum conditions, 60.4% 1,3-DAG and 61.3% LA-DAG in the crude product at 1 h reaction were obtained, and further purified to 81.7% LA-DAG and 94.7% DAG via silica column chromatography. CONCLUSION: The present study provides a guideline for the identification of DAG species, as well as a structure-guided preparation method of DAG-enriched oils via the cost-effective combi-lipase. © 2022 Society of Chemical Industry.


Asunto(s)
Camellia , Diglicéridos , Diglicéridos/química , Ácido Linoleico , Lipasa/química , Aceites de Plantas/química , Glicéridos , Ácidos Grasos no Esterificados
8.
Prep Biochem Biotechnol ; 53(7): 763-772, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36332158

RESUMEN

India generates 126.6 and 42 million tons of Rice straw (RS) and Rice husk (RH) annually, respectively. These agro-processing wastes feedstock are dumped in landfills or burnt, releasing toxic gases and particulate matter into the environment. This paper explores the valorization of these wastes feedstock into sustainable, economic products. We compare these wastes as matrices for lipase immobilization. These matrices were characterized, different parameters (pH, temperature, ionic strength, and metal ion cofactors) were checked, and the selected matrix was analyzed for reusability and hydrolysis of vegetable oils. Lipase immobilized Rice straw (LIRS) showed the highest activity with 72.84% protein loading. Field emission scanning electron microscopy (FESEM) demonstrated morphological changes after enzyme immobilization. FTIR showed no new bond formation, and immobilization data was fitted to Freundlich adsorption isotherm (with K = 12.18 mg/g, nF = 4.5). The highest activity with protein loading, 91.05%, was observed at pH 8, 37 °C temperature, 50 mM ionic strength, and lipase activity doubled in the presence of Mg2+ ions. The LIRS retained 75% of its initial activity up to five cycles and efficiently hydrolyzed different oils. The results reflected that the LIRS system performs better and can be used to degrade oily waste.


Asunto(s)
Lipasa , Oryza , Lipasa/química , Oryza/metabolismo , Hidrólisis , Enzimas Inmovilizadas/química , Aceites de Plantas , Adsorción , Concentración de Iones de Hidrógeno
9.
Appl Biochem Biotechnol ; 195(1): 432-450, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36087232

RESUMEN

The enzymatic production of biodiesel from waste cooking oils (WCOs) offers a green and sustainable solution for the liquid fuel manufacture as well as waste resource recovery. In present study, liquid lipase was used to simplify the catalysis process, thereby reducing biodiesel production costs. An engineered Escherichia coli expressing Geobacillus thermocatenulatus lipase 2 (GTL2) was screened at an enzyme activity of 6.96 U/mg, after evaluating the propagating stability of the recombinant plasmids exceeding 86.11%. Through the beneficial feeding strategy and effective pH control, high-level production of GTL2 by fed-batch fermentation was achieved with an enzyme activity of 434.32 U/mg, which was almost 62 times that of shake flask fermentation. In addition, liquid GTL2 was used to prepare fatty acid methyl esters (FAMEs) using WCOs. The effects of the reaction time, catalyst loading, temperature, and methanol-to-oil molar ratio on FAMEs production using WCOs were explored, and a maximum FAMEs yield of 96.62% was achieved under optimized conditions. These results indicate that liquid GTL2 is a promising biocatalyst for efficient utilization of WCOs in the synthesis of biodiesel and provide a novel enzymatic process for biodiesel reducing the cost of production.


Asunto(s)
Biocombustibles , Lipasa , Lipasa/química , Fermentación , Escherichia coli/genética , Escherichia coli/metabolismo , Esterificación , Enzimas Inmovilizadas/química , Aceites , Catálisis , Culinaria , Aceites de Plantas/química
10.
Molecules ; 27(24)2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36557867

RESUMEN

Biodiesel is one of the important biofuels as an alternative to petroleum-based diesel fuels. In the current study, enzymatic transesterification reaction was carried out for the production of biodiesel from waste cooking oil (WCO) and experimental conditions were optimized, in order to reach maximum biodiesel yield. Bacillus stearothermophilus and Staphylococcus aureus lipase enzymes were individually immobilized on CaCO3 to be used as environmentally friendly catalysts for biodiesel production. The immobilized lipases exhibited better stability than free ones and were almost fully active after 60 days of storage at 4 °C. A significant biodiesel yield of 97.66 ± 0.57% was achieved without any pre-treatment and at 1:6 oil/methanol molar ratio, 1% of the enzyme mixture (a 1:1 ratio mixture of both lipase), 1% water content, after 24 h at 55 °C reaction temperature. The biocatalysts retained 93% of their initial activities after six cycles. The fuel and chemical properties such as the cloud point, viscosity at 40 °C and density at 15 °C of the produced biodiesel complied with international specifications (EN 14214) and, therefore, were comparable to those of other diesels/biodiesels. Interestingly, the resulting biodiesel revealed a linolenic methyl ester content of 0.55 ± 0.02% and an ester content of 97.7 ± 0.21% which is in good agreement with EN14214 requirements. Overall, using mixed CaCO3-immobilized lipases to obtain an environmentally friendly biodiesel from WCO is a promising and effective alternative for biodiesel production catalysis.


Asunto(s)
Biocombustibles , Ésteres , Biocombustibles/análisis , Esterificación , Lipasa/química , Enzimas Inmovilizadas/metabolismo , Culinaria , Aceites de Plantas
11.
Anal Methods ; 14(32): 3071-3078, 2022 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-35924567

RESUMEN

Different vegetable oils have different nutritional components, especially in terms of the composition of their fatty acids, which can only be reflected after entering the human body. Therefore, when judging their health value and identifying high-quality vegetable oils, in addition to the analysis of their ingredients, tracking their hydrolysis process in the human body is a very important aspect. However, most identification methods or simulated digestion studies fail to achieve this. In this paper, we applied ordered porous layer interferometry (OPLI) for the real-time monitoring of optical thickness changes (ΔOT) to track the hydrolysis process of four kinds of vegetable oil. Further, this study can obtain precise data (the initial rate and degree of hydrolysis) to provide more information on the hydrolysis ability of different vegetable oils and give references for their nutritional and functional evaluation. In addition, it provides more possibilities for the adulteration identification and bioavailability analysis of vegetable oils.


Asunto(s)
Lipasa , Aceites de Plantas , Humanos , Hidrólisis , Interferometría , Lipasa/química , Dióxido de Silicio
12.
Molecules ; 27(11)2022 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-35684413

RESUMEN

As for ligand fishing, the current immobilization approaches have some potential drawbacks such as the small protein loading capacity and difficult recycle process. The core-shell metal-organic frameworks composite (Fe3O4-COOH@UiO-66-NH2), which exhibited both magnetic characteristics and large specific surface area, was herein fabricated and used as magnetic support for the covalent immobilization of porcine pancreatic lipase (PPL). The resultant composite Fe3O4-COOH@UiO-66-NH2@PPL manifested a high loading capacity (247.8 mg/g) and relative activity recovery (101.5%). In addition, PPL exhibited enhanced tolerance to temperature and pH after immobilization. Then, the composite Fe3O4-COOH@UiO-66-NH2@PPL was incubated with the extract of Scutellaria baicalensis to fish out the ligands. Eight lipase inhibitors were obtained and identified by UPLC-Q-TOF-MS/MS. The feasibility of the method was further confirmed through an in vitro inhibitory assay and molecular docking. The proposed ligand fishing technique based on Fe3O4-COOH@UiO-66-NH2@PPL provided a feasible, selective, and effective platform for discovering enzyme inhibitors from natural products.


Asunto(s)
Lipasa , Estructuras Metalorgánicas , Animales , Enzimas Inmovilizadas/química , Ligandos , Lipasa/química , Fenómenos Magnéticos , Estructuras Metalorgánicas/química , Simulación del Acoplamiento Molecular , Ácidos Ftálicos , Extractos Vegetales/farmacología , Scutellaria baicalensis , Porcinos , Espectrometría de Masas en Tándem
13.
J Sci Food Agric ; 102(15): 6921-6929, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35662022

RESUMEN

BACKGROUND: Crude palm oil (CPO) is rich with phytonutrients such as carotenoids and tocols which possesses many health benefits. The aim of this research was to develop a methanol-free process to produce palm phytonutrients via enzymatic hydrolysis. In this work, triacylglycerol was hydrolyzed into free fatty acids (FFAs) using three different types of liquid lipases derived from Aspergillus oryzae (ET 2.0), Aspergillus niger (Habio) and Candida antartica (CALB). RESULTS: ET 2.0 was found to be the best enzyme for hydrolysis. Under the optimum condition, the FFA content achievable was 790 g kg-1 after 24 h of reaction with 1:1 water-to-oil mass ratio at 50 °C and stirring speed of 9 × g. Furthermore, with the addition of 2 g kg-1 ascorbic acid, it was found that 98% of carotenoids and 96% of tocols could be retained after hydrolysis. CONCLUSION: This work shows that enzymatic hydrolysis, which is inherently safer, cleaner and sustainable is feasible to replace the conventional methanolysis for the production of palm phytonutrients. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Petróleo , Aceite de Palma/química , Hidrólisis , Lipasa/química , Ácidos Grasos no Esterificados , Etanol , Carotenoides , Fitoquímicos , Aceites de Plantas/química
14.
Molecules ; 27(9)2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35566043

RESUMEN

In this study, soybean oil deodorizer distillate (SODD), a mixture of free fatty acids and acylglycerides, and isoamyl alcohol were evaluated as substrates in the synthesis of fatty acid isoamyl monoesters catalyzed by Eversa (a liquid formulation of Thermomyces lanuginosus lipase). SODD and the products were characterized by the chemical and physical properties of lubricant base stocks. The optimal conditions to produce isoamyl fatty acid esters were determined by response surface methodology (RSM) using rotational central composite design (RCCD, 23 factorial + 6 axial points + 5 replications at the central point); they were 1 mol of fatty acids (based on the SODD saponifiable index) to 2.5 mol isoamyl alcohol, 45 °C, and 6 wt.% enzymes (enzyme mass/SODD mass). The effect of the water content of the reactional medium was also studied, with two conditions of molecular sieve ratio (molecular sieve mass/SODD mass) selected as 39 wt.% (almost anhydrous reaction medium) and 9 wt.%. Ester yields of around 50 wt.% and 70 wt.% were reached after 50 h reaction, respectively. The reaction products containing 43.7 wt.% and 55.2 wt.% FAIE exhibited viscosity indices of 175 and 163.8, pour points of -6 °C and -9 °C, flash points of 178 and 104 °C, and low oxidative stability, respectively. Their properties (mainly very high viscosity indices) make them suitable to be used as base stocks in lubricant formulation industries.


Asunto(s)
Lubricantes , Aceite de Soja , Esterificación , Ácidos Grasos/química , Lipasa/química , Aceite de Soja/química
15.
Eur J Pharm Biopharm ; 176: 32-42, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35584719

RESUMEN

The digestion behaviour of lipid-based nanocarriers (LNC) has a great impact on their oral drug delivery properties. In this study, various excipients including surfactants, glycerides and waxes, as well as various drug-delivery systems, namely self-emulsifying drug delivery systems (SEDDS), solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) were examined via the pH-stat lipolysis model. Lipolysis experiments with lipase and pancreatin revealed the highest release of fatty acids for medium chain glycerides, followed by long chain glycerides and surfactants. Waxes appeared to be poor substrates with a maximum digestion of up to 10% within 60 min. Within the group of surfactants, the enzymatic cleavage decreased in the following order: glycerol monostearate > polyoxyethylene (20) sorbitan monostearate > PEG-35 castor oil > sorbitan monostearate. After digestion experiments of the excipients, SEDDS, SLN and NLC with sizes between 30 and 300 nm were prepared. The size of almost all formulations was increasing during lipolysis and levelled off after approximately 15 min except for the SLN and NLC consisting of cetyl palmitate. SEDDS exceeded 6000 nm after some minutes and were almost completely hydrolysed by pancreatin. No significant difference was observed between comparable SLN and NLC but surfactant choice and selection of the lipid component had an impact on digestion. SLN and NLC with cetyl palmitate were only digested by 5% whereas particles with glyceryl distearate were decomposed by 40-80% within 60 min. Additionally, the digestion of the same SLN or NLC, only differing in the surfactant, was higher for SLN/NLC containing polyoxyethylene (20) sorbitan monostearate than PEG-35 castor oil. This observation might be explained by the higher PEG content of PEG-35 castor oil causing a more pronounced steric hindrance for the access of lipase. Generally, digestion experiments performed with pancreatin resulted in a higher digestion compared to lipase. According to these results, the digestion behaviour of LNC depends on both, the type of nanocarrier and on the excipients used for them.


Asunto(s)
Excipientes , Nanopartículas , Aceite de Ricino , Digestión , Portadores de Fármacos/química , Excipientes/química , Glicéridos/química , Lipasa/química , Lípidos/química , Liposomas , Nanopartículas/química , Pancreatina/química , Tamaño de la Partícula , Polietilenglicoles , Tensoactivos/química , Ceras
16.
PLoS One ; 17(2): e0263507, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35120192

RESUMEN

A 65-day growth trial was conducted to investigate the dietary protein requirements for Culter mongolicus fingerlings. Isolipidic and isoenergetic diets were formulated with five dietary protein levels (32%, 37%, 42%, 47%, and 52%). Each diet was assigned to triplicate groups of 70 C. mongolicus fingerlings (0.99±0.08 g). The results indicated that weight gain and specific growth rate (SGR) increased with increasing dietary protein levels up to 47%. The activities of intestinal trypsin and lipase were the lowest in the 32% protein and 52% protein groups, while amylase activity reduced markedly in the 47% protein group. These results suggest that different dietary protein levels may cause different transformations of nutrients. The activities of superoxide dismutase (SOD) and lysozyme were not affected by varying dietary protein levels, except for those in the 32% protein group. In contrast, the content of malondialdehyde (MDA) increased with increasing dietary protein levels and reaching a maximum in the 52% protein group, suggesting that MDA accumulation depends on the protein concentration and the potential oxidative stress. Taken together, based on the broken-line analysis of SGR, we recommended the optimum dietary protein for C. mongolicus fingerlings to be 48.97%~49.31%.


Asunto(s)
Proteínas en la Dieta/metabolismo , Muramidasa/metabolismo , Estrés Oxidativo , Superóxido Dismutasa/metabolismo , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Antioxidantes/metabolismo , Dieta , Suplementos Dietéticos/análisis , Peces , Sistema Inmunológico , Lipasa/química , Necesidades Nutricionales , Tripsina/química
17.
Appl Biochem Biotechnol ; 194(5): 2151-2167, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35050455

RESUMEN

Lipases are an important group of biocatalysts for many industrial applications. Two new commercial low-cost lipases Eversa® Transform and Eversa® Transform 2.0 was immobilized on four different hydrophobic supports: Lewatit-DVB, Purolite-DVB, Sepabeads-C18, and Purolite-C18. The performance of immobilized lipases was investigated in the transesterification of sunflower oil solvent-free in an anhydrous medium. Interesting results were obtained for both lipases and the four supports, but with Sepabeads support the lipases Eversa showed high catalytic activity. However, the more stable and efficient derivative was Eversa® Transform immobilized on Sepabeads C-18. A 98 wt% of ethyl ester of fatty acid (FAEE) was obtained, in 3 h at 40ºC, ethanol/sunflower oil molar ratio of 3:1 and a 10 wt% of the immobilized biocatalyst. After 6 reaction cycles, the immobilized biocatalyst preserved 70 wt% of activity. Both lipases immobilized in Sepabeads C-18 were highly active and stable in the presence of ethanol. The immobilization of Eversa Transform and Eversa Transform 2.0 in hydrophobic supports described in this study appears to be a promising alternative to the immobilization and application of these news lipases still unexplored.


Asunto(s)
Enzimas Inmovilizadas , Lipasa , Enzimas Inmovilizadas/química , Etanol/química , Lipasa/química , Solventes , Aceite de Girasol/química
18.
Chembiochem ; 23(2): e202100578, 2022 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-34726829

RESUMEN

Fatty amines represent an important class of commodity chemicals which have broad applicability in different industries. The synthesis of fatty amines starts from renewable sources such as vegetable oils or animal fats, but the process has multiple drawbacks that compromise the overall effectiveness and efficiency of the synthesis. Herein, we report a proof-of-concept biocatalytic alternative towards the synthesis of primary fatty amines from renewable triglycerides and oils. By coupling a lipase with a carboxylic acid reductase (CAR) and a transaminase (TA), we have accomplished the direct synthesis of multiple medium and long chain primary fatty amines in one pot with analytical yields as high as 97 %. We have also performed a 75 mL preparative scale reaction for the synthesis of laurylamine from trilaurin, obtaining 73 % isolated yield.


Asunto(s)
Aminas/síntesis química , Grasas/química , Aceites de Plantas/química , Triglicéridos/química , Lipasa/química , Oxidorreductasas/química , Transaminasas/química
19.
Biotechnol Appl Biochem ; 69(5): 1812-1820, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34486738

RESUMEN

Due to its simple, less by-product and environment friendly properties, enzymatic transesterification of oil with short-chain alcohol to biodiesel, fatty acid methyl esters (FAMEs) is considered to be a promising way of green production and has attracted much attention. In this study, FAMEs were synthesized by an enzymatic method with recombinant lipase as catalysts. A thermophilic Bacillus thermocatenulatus lipase 2 (BTL2) was overexpressed in Escherichia coli BL21(DE3) through relative and quantitative analysis using real-time quantitative PCR. The results suggested that the BTL2 gene was overexpressed in E. coli at the mRNA level, and the recombinant strain harboring a high-copy number vectors was selected and applied to fermentation to produce BTL2 with enzyme activity of 35.54 U/mg cells. The recombinant BTL2 solution exhibited excellent resistance to neutral pH, high temperature, and organic solvents after a certain treatment. Finally, the effects of enzymatic transesterification for preparing biodiesel were studied, using rapeseed oil as raw material, as well as BTL2 solution as catalysts, which resulted in 86.04% yield of FAMEs under 50°C for 36 h. The liquid BTL2 was directly used to prepare FAMEs at a higher temperature efficiently, making the thermophilic BTL2 had the potential application value in biodiesel reproduction subsequently.


Asunto(s)
Biocombustibles , Lipasa , Lipasa/química , Escherichia coli/genética , Escherichia coli/metabolismo , Aceite de Brassica napus , Fermentación , Calor , Ácidos Grasos/química
20.
Prep Biochem Biotechnol ; 52(8): 942-949, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34927572

RESUMEN

The present work aims to study the production of a new extracellular lipase from the endophytic fungus Preussia africana isolated from red lapacho tree (Handroanthus impetiginosus). Tests were carried out in order to evaluate the influence of different inducing oils (sunflower, cotton, corn, palm kernel, canola and linseed) and carbon/nitrogen ratio (C/N of 11.73, 8.63 and 7.05) on submerged fermentation aiming at optimal production of a single extracellular lipase. Results show that an optimal lipase production of 14.5 kDa has been attained after 48 h of fermentation when sunflower oil was used in the C/N ratio of 8.63 in the fermentation medium. The produced lipase showed greater activity for oils that had higher percentage of unsaturated fatty acids in their composition. Characterization was performed using a two-factor central composite rotatable design (CCRD), and the pH 6 was found to be optimal (around 28 U/mL). The temperature range studied (from 20 to 54 °C) showed no difference for the lipase catalytic activity. This is an advantage, especially when aiming at its application in reactions of industrial interest.


Asunto(s)
Lipasa , Aceites de Plantas , Ascomicetos , Fermentación , Concentración de Iones de Hidrógeno , Lipasa/química , Aceites de Plantas/química , Temperatura
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