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1.
Food Chem ; 366: 130553, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34284194

RESUMO

A method for real-time monitoring of lipid digestion based on photonic crystals formed from silica was developed. As an effective "net", the highly ordered silica colloidal crystal (SCC) film provides structural support for lipid payload. This method based on optical interferometric film kinetics was used to record the whole kinetics progress of olive oil hydrolysis by lipase in real time and calculate the kinetic Michaelis constant. The kinetic parameters were compared with the results determined by the titration method. The effects of bile salt content on lipase and olive oil layer were studied. This method provides a potential evaluation system for real-time digestion and degradation of edible oil in the food field. It also provides a basis for further real-time evaluation of lipid bioavailability in food systems by real-time recording the release and degradation of lipids in the food nano-matrix.


Assuntos
Lipídeos , Lipólise , Digestão , Interferometria , Lipase/metabolismo
2.
Food Chem ; 366: 130523, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34303206

RESUMO

Our study offers a novel sn-1,3 specific lipase MAJ1 from marine member Janibacter sp. strain HTCC2649 for preparing long-medium-long (LML) type structured triacylglycerols (TAGs). Firstly, the resin ECR1030 was selected as a suitable support for the immobilization of lipase MAJ1. An efficient synthesis of LML-type structured TAGs by the immobilized lipase MAJ1-catalyzed interesterification of methyl palmitate and tricaprylin was studied in a solvent-free system. The reaction conditions, including substrate molar ratio, temperature and enzyme loading, were optimized. Under the optimum conditions (immobilized lipase MAJ1 of 45 U/g, substrate molar ratio of 4:1, temperature of 35 °C, reaction time of 24 h), the structured TAGs with double long chains (DLCST) were obtained in a yield of 44.3 mol%. Secondly, multi-dimensional mass spectrometry-based shotgun lipidomics (MDMS-SL) was employed to quantify each TAG positional isomer in DLCST. The content of 1,3-dipalmitoyl-2-capryloyl-sn-glycerol in DLCST was 97.6% determined by the MDMS-SL technology.


Assuntos
Enzimas Imobilizadas , Lipase , Catálise , Esterificação , Lipase/metabolismo , Solventes , Temperatura , Triglicerídeos
3.
Food Chem ; 366: 130616, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311240

RESUMO

The lipase from Bacillus licheniformis NCU CS-5 was immobilized onto ß-cyclodextrin (CD) grafted and aminopropyl-functionalized chitosan-coated Fe3O4 magnetic nanocomposites (Fe3O4-CTS-APTES-GA-ß-CD). Fourier transform infrared spectroscopy, thermogravimetry analysis, X-ray diffraction, scanning electron microscopy and transmission electron microscopy showed that not only the functionalized magnetic nanoparticles were synthesized but also the immobilized lipase was successfully produced. The immobilized lipase exhibited higher optimal pH value (10.5) and temperature (60℃) than the free lipase. The pH and thermal stabilities of the immobilized lipase were improved significantly compared to the free lipase. The immobilized lipase remained more than 80% of the relative activity at temperature of 60 ℃ and pH 12.0. The immobilized lipase also remained over 80% of its relative activity after 28 days of storage and 15 cycles of application. The application of the immobilized lipase in esterification of isoamyl acetate and pentyl valerate showed that maximum esterification efficiency was achieved in n-hexane having 68.0% and 89.2% respectively. Therefore, these results indicated that the Fe3O4-CTS-APTES-GA-ß-CD nanoparticles are novel carriers for immobilizing enzyme, and the immobilized lipase can be used as an innovative green approach to the synthesis of fruity flavor esters in food industry.


Assuntos
Quitosana , Ciclodextrinas , Nanopartículas de Magnetita , Nanocompostos , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Esterificação , Ésteres , Concentração de Íons de Hidrogênio , Lipase/metabolismo , Fenômenos Magnéticos
4.
Food Chem ; 366: 130650, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34330030

RESUMO

Mixed lauric acid esters (MLE) with antibacterial and antioxidative activities were produced through lipase-catalyzed two-step esterification in solvent-free system without purification. In the first reaction, erythorbyl laurate was synthesized for 72 h. Successive reaction for 6 h at molar ratio of 1.0 (lauric acid to glycerol) produced MLE containing erythorbyl laurate and glyceryl laurate with small amounts of residual substrates, by converting 99.52% of lauric acid. MLE addition (0.5-2.0%, w/w) to Tween 20-stabilized emulsions decreased droplet size, polydispersity index, and zeta-potential, possibly enhancing the emulsion stability. In the emulsions, MLE at 0.5 and 2.0% (w/w) caused 4.4-4.6 and 5.9-6.1 log reductions of Gram-positive (Staphylococcus aureus, Listeria monocytogenes) and Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa), respectively, within 12 h. Lipid hydroperoxide concentrations decreased to 50.8-98.3% in the presence of 0.5-2.0% (w/w) MLE. These findings support a novel approach without needing purification to produce multi-functional food additives for emulsion foods.


Assuntos
Ésteres , Lipase , Antibacterianos/farmacologia , Antioxidantes , Catálise , Esterificação , Ácidos Láuricos , Lipase/metabolismo , Solventes
5.
Food Chem ; 366: 130699, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34348221

RESUMO

In this work, magnetic chitosan (MCH) beads were synthesized by phase-inversion method, and grafted with polydopamine (PDA) and then used for direct immobilization of Candida rugosa lipase by Schiff base reaction. The amount of immobilized enzyme and the retained activity were found to be 47.3 mg/g and 72.8%, respectively, at pH 7.0, and at 25 °C. The apparent Km (9.7 mmol/L), and Vmax (384 U/mg) values of the immobilized lipase were significantly changed compared to the free lipase. The MCH@PDA-lipase was better thermal and storage stability at different temperatures than those of the free lipase. In hexane medium, the esterification reaction results showed that the maximum conversions of isoamylalcohol and isopentyl alcohol to isoamyl acetate and isopentyl acetate using the MCH@PDA-lipase were found to be 98.4 ± 1.3% and 73.7 ± 0.7%, respectively. These results showed that the MCH@PDA-lipase can be used as an operative immobilized enzyme system for many biotechnological applications.


Assuntos
Quitosana , Lipase , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Ésteres , Concentração de Íons de Hidrogênio , Lipase/metabolismo , Fenômenos Magnéticos , Saccharomycetales
6.
Enzyme Microb Technol ; 150: 109870, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34489029

RESUMO

The propeptide is a short sequence that facilitates protein folding. In this study, four highly active Rhizomucor miehei lipase (RML) mutants were obtained through saturation mutagenesis at three propeptide positions: Ser8, Pro35, and Pro47. The enzyme activities of mutants P35 N, P47 G, P47 N, and S8E/P35S/P47A observed at 40 °C, and pH 8.0 were 10.19, 7.53, 6.15, and 8.24 times of that wild-type RML, respectively. The S8E/P35S/P47A mutant showed good thermostability. After incubation at 40 °C for 1 h, 98.98 % of its initial activity remained, whereas wild-type RML retained only 78.76 %. This result indicated that the enhancement of hydrophilicity of 35- and 47- amino-acid residues could promote the interaction between the propeptide and the mature peptide and the enzyme activity and expression level. Highly conserved sites had a more significant impact on enzyme performance than did other sites, similar to the Pro35 and Pro47 mutants showed in this study. This study provides a new idea for protein modification: enzyme performance can be improved through propeptide regulation.


Assuntos
Lipase , Rhizomucor , Lipase/genética , Lipase/metabolismo , Mutação , Dobramento de Proteína , Rhizomucor/genética
7.
Life Sci ; 283: 119866, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34352257

RESUMO

AIMS: Morphine, a commonly used drug for anesthesia, affects lipid metabolism in different tissues, but the mechanism is currently unclear. Adipose triglyceride lipase (ATGL) is the rate-limiting enzyme responsible for the first step of triglyceride (TG) hydrolysis. Here we aim to investigate whether ATGL phosphorylation is involved in morphine-induced TG accumulation. MAIN METHODS: Oil red O staining and TG content analysis were used to detect the effect of morphine on lipid storage. A series of ATGL phosphoamino acid site mutant plasmids were constructed by gene synthesis and transfected to HL-1 cells to evaluate the phosphorylation levels of ATGL phosphoamino acid in morphine-treated HL-1 cells with immunoprecipitation and immunoblotting assay. KEY FINDINGS: Morphine acute treatment induced excessive accumulation of TG and decreased the phosphorylation level of ATGL Ser406 in HL-1 cells. Of note, the phosphorylation positive mutation of ATGL Ser406 to aspartic acid effectively reversed morphine-induced excessive accumulation of TG in HL-1 cells. SIGNIFICANCE: This discovery will help to fully understand the lipid regulation function of morphine in a new scope. In addition, it will expand the phosphorylation research of ATGL more comprehensively and provide powerful clues for lipid metabolism regulation.


Assuntos
Lipase/metabolismo , Morfina/farmacologia , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Triglicerídeos/biossíntese , Animais , Linhagem Celular , Masculino , Camundongos , Morfina/farmacocinética , Miocárdio/patologia , Miócitos Cardíacos/patologia , Fosforilação/efeitos dos fármacos
8.
Biomed Res Int ; 2021: 5577498, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34337029

RESUMO

Postmenopausal women express great failure in their ovarian hormone production, especially estrogen. This deficiency may promote hypercholesterolemia and accelerate the redox imbalance. The present study was designed to evaluate the protective effect of Avena sativa against estrogen deficiency-induced liver and uterus oxidative injury in experimental ovariectomized mice. Female mice were randomly divided into five groups: group one (negative control) received normal diet and distilled water (C), group two (positive control) received daily enriched diet with oat grains and was kept on tap distilled water at a dose of 200 mg kg-1 d-1 (A), group three (ovariectomized mice) was nontreated fed with normal diet (O), group four includes ovariectomized mice treated daily with estradiol given by intraperitoneal injection at a dose of 100 µg kg-1 d-1 (OE), and the fifth group also includes ovariectomized mice which received enriched diet with oat grain parts with the same dose given to group two. The treatment period lasted two consecutive months. Both oat and hormonal treatments of ovariectomized groups resulted in a significant reduction in triglycerides and total cholesterol and increased high-density lipoprotein (HDL) levels in the plasma after 21 and 60 days of treatment. Besides, the coadministration of A. sativa has decreased the activities of alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) and increased transaminase activities after 21 and 60 days of treatment. On the other hand, this cereal has restored the enzymatic (SOD, CAT, and GPx) and nonenzymatic antioxidant activities (GSH) as well as the elevated thiobarbituric acid reactive substances (AOPP and PCO) to near-normal values. The beneficial effects of this cereal were confirmed by a histological study of the liver and uterus of all previous cited groups. Our finding emphasized the antioxidant and antilipidemic effect of oat grain part, suggesting the use of this cereal in the prevention of liver and uterus diseases that occurred in postmenopausal women.


Assuntos
Avena/química , Fígado/patologia , Ovariectomia , Estresse Oxidativo , Substâncias Protetoras/farmacologia , Animais , Antioxidantes/farmacologia , Biomarcadores/sangue , Inibidores Enzimáticos/farmacologia , Etanol/química , Feminino , Lipase/antagonistas & inibidores , Lipase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos/sangue , Fígado/efeitos dos fármacos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Carbonilação Proteica , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Útero/efeitos dos fármacos , Útero/patologia
9.
Biomolecules ; 11(6)2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34200103

RESUMO

The study aimed to evaluate the impact of selected factors of the freeze-drying process on the hydrolytic and synthetic activity of the extracellular lipases of Y. lipolytica KKP 379 and to attempt the use of the crude enzyme preparation as a biocatalyst in the synthesis of geranyl 4-hydroxyphenylpropanoate. Antioxidant and antibacterial properties of the geranyl ester derivative were also investigated in order to evaluate their usefulness as a novel food additive. The studies confirmed that freeze-drying was an effective method of dehydrating yeast supernatant and allowed for obtaining lyophilizates with low water activity from 0.055 to 0.160. The type and concentration of the additive (2-6% whey protein hydrolyzate, 0.5% and 1% ammonium sulphate) had a significant effect on the hydrolytic activity of enzyme preparations, while the selected variants of drying temperature during the freeze-drying process were not significant (10 °C and 50 °C). Low yield of geranyl 4-hydroxyphenylopropionate was shown when the lyophilized supernatant was used (5.3%), but the yield of ester synthesis increased when the freeze-dried Y. lipolytica yeast biomass was applied (47.9%). The study confirmed the antioxidant properties of the synthesized ester by the DPPH• and CUPRAC methods, as well as higher antibacterial activity against tested bacteria than its precursor with 0.125 mM MIC (minimal inhibitory concentration) against L. monocytogenes.


Assuntos
Monoterpenos Acíclicos/metabolismo , Líquido Extracelular/enzimologia , Lactatos/metabolismo , Lipase/metabolismo , Yarrowia/enzimologia , Monoterpenos Acíclicos/síntese química , Antibacterianos/síntese química , Antibacterianos/metabolismo , Antioxidantes/síntese química , Antioxidantes/metabolismo , Catálise , Ésteres , Liofilização/métodos , Lactatos/síntese química , Lipase/química , Testes de Sensibilidade Microbiana/métodos , Yarrowia/química
10.
Biomolecules ; 11(6)2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200257

RESUMO

Water content is an important factor in lipase-catalyzed reactions in organic media but is frequently ignored in the study of lipases by molecular dynamics (MD) simulation. In this study, Candida antarctica lipase B, Candida rugosa lipase and Rhizopus chinensis lipase were used as research models to explore the mechanisms of lipase in micro-aqueous organic solvent (MAOS) media. MD simulations indicated that lipases in MAOS systems showed unique conformations distinguished from those seen in non-aqueous organic solvent systems. The position of water molecules aggregated on the protein surface in MAOS media is the major determinant of the unique conformations of lipases and particularly impacts the distribution of hydrophilic and hydrophobic amino acids on the lipase surface. Additionally, two maxima were observed in the water-lipase radial distribution function in MAOS systems, implying the formation of two water shells around lipase in these systems. The energy landscapes of lipases along solvent accessible areas of catalytic residues and the minimum energy path indicated the dynamic open states of lipases in MAOS systems differ from those in other solvent environments. This study confirmed the necessity of considering the influence of the microenvironment on MD simulations of lipase-catalyzed reactions in organic media.


Assuntos
Microambiente Celular/fisiologia , Biologia Computacional/métodos , Lipase/química , Simulação de Dinâmica Molecular , Água/química , Basidiomycota/química , Basidiomycota/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Lipase/análise , Lipase/metabolismo , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Saccharomycetales/química , Saccharomycetales/metabolismo , Água/metabolismo
11.
J Biotechnol ; 337: 24-34, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34197821

RESUMO

A thermostable T1 lipase from Geobacillus zalihae exhibits broad substrate specificity and good potential application in fats and oils. However, structural insight into the enzyme against substrates is poorly understood at the molecular level. Herein, the study aimed to examine interactions between a mutant T1 lipase (Mut-T1 lipase) and selected fatty acids (caprylic, myristic, stearic, oleic, linoleic and linolenic acids) by performing molecular docking and molecular dynamics (MD) simulation. The structure of Mut-T1 lipase obtained by homology modeling was reliable for molecular docking and MD simulation. Molecular docking revealed that Mut-T1 lipase showed low binding affinity for caprylic acid (-4.97 kcal/mol) compared to the other fatty acids (-5.65 to -6.88 kcal/mol). However, the conformation of Mut-T1 lipase-caprylic acid complex was comparably stable during the simulation, in terms of less root-mean square fluctuation. Besides, solvent accessible surface area value of Mut-T1 lipase-fatty acid complexes decreased with increasing chain length of fatty acid. van der Waals interactions were requisite in maintaining complex stability during the binding process. This work provides structural insight into interactions between the lipase and the fatty acids, which will facilitate design and applications of new mutants of T1 lipase in modifying fats and oils.


Assuntos
Ácidos Graxos , Simulação de Dinâmica Molecular , Geobacillus , Lipase/genética , Lipase/metabolismo , Simulação de Acoplamento Molecular
12.
J Biotechnol ; 337: 46-56, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34197823

RESUMO

Esculin is a polyphenol with multiple bioactivities and poor lipophilicity. Therefore, a whole-cell catalytic strategy for esculin acylation was developed to improve its lipophilicity. A total of 12 strains were tested, among which Pseudomonas stutzeri exhibited the highest catalytic activity and mono-acylated regioselectivity. The conversion reached the highest level of 92.7 % at 24 h under the optimal conditions, when vinyl acetate was used as an acyl donor. The catalytic ability of P. stutzeri remained above 60 % after three cycles. Subsequently, five esculin esters with different lengths of fatty chains were synthesized and structurally identified. Of them, esculin-6'-O-octanoate, esculin-6'-O-laurate, and esculin-6'-O-myristate exhibited cytotoxicity on LO2 cells by inducing apoptosis and necrosis. The cytotoxicity of these three esters may attribute to their membrane-disrupting properties. This study provides a novel whole-cell biocatalytic strategy for the acylation of esculin and insight for application of esculin esters as a food additive or drug.


Assuntos
Esculina , Ésteres , Acilação , Biocatálise , Lipase/metabolismo
13.
Fish Shellfish Immunol ; 116: 98-106, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34252543

RESUMO

Medicinal herbs are used for growth promotion, disease control and other health benefits in aquaculture industry. Here, we examined the effect of dietary laurel-leaf cistus (Cistus laurifolius) ethanolic extract on growth performance, digestive enzyme activity, haematological profile and nonspecific immune responses in common carp (Cyprinus carpio). In addition, resistance against Aeromonas hydrophila infection was examined. Common carp was fed diets containing 0 (Control), 0.1 (CL0.1), 0.5 (CL0.5) and 1 (CL1) g kg-1 laurel-leaf cistus extract for 45 days. After 30 days, superoxide anion production (SAP) increased in CL0.1 and CL0.5 fish groups and at the end of the study all experimental fish groups had higher SAP compared to that of the control (P ˂ 0.05). Lysozyme activity (LA) was elevated in CL0.5 and CL1 treated groups on 30th day (P < 0.05), and this increase was only observed in C0.1 fish group at the end of study compared to control (P ˂ 0.05). Myeloperoxidase activity was significantly increased in CL0.5 and CL1 fish groups at the end of study. IL-1ßgene expression was significantly increased in treated fish in a dose-depended manner. Similar results were observed for transcription of IL-6 and IL-8 (P < 0.05). Anti-inflammatory cytokines, IL-10 and TGF-ß were highly up-regulated in the intestine and head kidney of CL treated fish groups compared to control (P < 0.05). At the end of experiment, significantly higher final body weight, weight gain, and specific growth rate were obtained in CL0.1 treated fish group compared to control. However, growth was negatively affected in CL1 fish group (P < 0.05). CL1 fish group had also a significantly higher FCR. Amylase activity was significantly increased in all experimental fish groups compared to control (P ˂ 0.05). Trypsin activity was decreased in CL0.1 and CL1 fish groups (P ˂ 0.05). WBC and RBC were significantly increased (P ˂ 0.05) in CL0.5 and CL1 fish groups, whereas haemoglobin, haematocrit, mean cell, mean cell haemoglobin contents were no significantly changed among control and treatment groups. Result of challenge test with A. hydrophila exhibited that survival rate in all treatment groups was significantly higher than that of control. These findings demonstrated that laurel-leaf cistus at 0.1 g kg-1 can be a suitable candidate for growth promotion, immune system induction and infection control in fish.


Assuntos
Carpas , Cistus , Doenças dos Peixes/prevenção & controle , Infecções por Bactérias Gram-Negativas/prevenção & controle , Imunidade Inata/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Extratos Vegetais/farmacologia , Aeromonas hydrophila , Amilases/metabolismo , Animais , Contagem de Células Sanguíneas , Carpas/sangue , Carpas/genética , Carpas/imunologia , Carpas/metabolismo , Citocinas/genética , Etanol/química , Infecções por Bactérias Gram-Negativas/veterinária , Rim Cefálico/citologia , Rim Cefálico/imunologia , Lipase/metabolismo , Muramidase/imunologia , Folhas de Planta/química , Solventes/química , Superóxidos/imunologia , Tripsina/metabolismo
14.
Molecules ; 26(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299456

RESUMO

The inhibition of certain digestive enzymes by target food matrices represents a new approach in the treatment of socially significant diseases. Proving the ability of fruits to inhibit such enzymes can support the inclusion of specific varieties in the daily diets of patients with diabetes, obesity, Alzheimer's disease, etc., providing them with much more than just valuable micro- and macromolecules. The current study aimed atidentifying and comparing the GC-MS metabolic profiles of eight peach varieties ("Filina", "Ufo 4, "Gergana", "Laskava", "July Lady", "Flat Queen", "Evmolpiya", and "Morsiani 90") grown in Bulgaria (local and introduced) and to evaluate the inhibitory potential of their extracts towards α-glucosidase, α-amylase, lipase, and acetylcholinesterase. In order to confirm samples' differences or similarities, principal component analysis (PCA) and hierarchical cluster analysis (HCA) were also applied to the identified metabolites. The results provide important insights into the metabolomic profiles of the eight peach varieties and represent a first attempt to characterize the peels of the peach varieties with respect to α-glucosidase-, α-amylase-, lipase-, and acetylcholinesterase-inhibitory activities. All of the studied peach extracts displayed inhibitory activity towards α-glucosidase (IC50: 125-757 mg/mL) and acetylcholinesterase (IC50: 60-739 mg/mL), but none of them affected α-amylase activity. Five of the eight varieties showed inhibitory activity towards porcine pancreatic lipase (IC50: 24-167 mg/mL). The obtained results validate the usefulness of peaches and nectarines as valuable sources of natural agents beneficial for human health, although further detailed investigation should be performed in order to thoroughly identify the enzyme inhibitors responsible for each activity.


Assuntos
Extratos Vegetais/farmacologia , Prunus persica/metabolismo , Acetilcolinesterase/metabolismo , Amilases/metabolismo , Antioxidantes/farmacologia , Bulgária , Inibidores da Colinesterase/farmacologia , Inibidores Enzimáticos/farmacologia , Frutas/química , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Inibidores de Glicosídeo Hidrolases/farmacologia , Lipase/antagonistas & inibidores , Lipase/metabolismo , Metaboloma , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Prunus persica/química , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
15.
Curr Microbiol ; 78(9): 3494-3504, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34279672

RESUMO

The gram-negative Pseudomonas aeruginosa is an opportunistic human pathogen that contains two different types of strains: the "classical" and the "outlier". In the "classical" strain, its bacterial subfamily I.1 lipases, such as LipA and LipC in P. aeruginosa PAO1, play critical roles in its pathogenicity. However, less is known about the subfamily I.1 lipases in the "outlier" strain, nor the evolution paths of those lipases in both types of P. aeruginosa strains. Our genome-scale investigation on I.1 lipases across different bacterial strains demonstrates the presence of one LipA-like and one new type of I.1 lipase (LipC2) in those "outlier" strains. The related genomic islands analyses further suggest that the LipC counterpart gene in the "outlier" strain was lost by gene truncation. In addition, the evolutionary analyses also indicates the horizontal LipC2 gene transfer from other gammaproteobacterial species, as well as the horizontal LipA gene transfer between two different phyla, both suggesting that the gene transfer of bacterial I.1 lipases might occur in different taxonomical levels. Our results not only provide an evidence to understand the pathogenicity among different P. aeruginosa strains, but add to the knowledge of I.1 lipase evolution in bacteria.


Assuntos
Lipase , Pseudomonas aeruginosa , Proteínas de Bactérias/genética , Transferência Genética Horizontal , Ilhas Genômicas , Humanos , Lipase/genética , Lipase/metabolismo , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Virulência
16.
Molecules ; 26(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208082

RESUMO

Cannabidiol (CBD) is a hydrophobic non-psychoactive compound with therapeutic characteristics. Animal and human studies have shown its poor oral bioavailability in vivo, and the impact of consuming lipid-soluble CBD with and without food on gut bioaccessibility has not been explored. The purpose of this research was to study the bioaccessibility of CBD after a three-phase upper digestion experiment with and without food, and to test lipase activity with different substrate concentrations. Our results showed that lipase enzyme activity and fatty acid absorption increased in the presence of bile salts, which may also contribute to an increase in CBD bioaccessibility. The food matrix used was a mixture of olive oil and baby food. Overall, the fed-state digestion revealed significantly higher micellarization efficiency for CBD (14.15 ± 0.6% for 10 mg and 22.67 ± 2.1% for 100 mg CBD ingested) than the fasted state digestion of CBD (0.65 ± 0.7% for 10 mg and 0.14 ± 0.1% for 100 mg CBD ingested). The increase in bioaccessibility of CBD with food could be explained by the fact that micelle formation from hydrolyzed lipids aid in bioaccessibility of hydrophobic molecules. In conclusion, the bioaccessibility of CBD depends on the food matrix and the presence of lipase and bile salts.


Assuntos
Ácidos e Sais Biliares/metabolismo , Canabidiol/farmacocinética , Alimentos , Lipase/metabolismo , Disponibilidade Biológica , Canabidiol/farmacologia , Digestão , Interações Alimento-Droga , Humanos , Técnicas In Vitro , Metabolismo dos Lipídeos , Micelas
17.
Molecules ; 26(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34205848

RESUMO

In this paper, we have performed the Lipozyme 435-catalyzed synthesis of xylose oleate in methyl ethyl ketone (MEK) from xylose and oleic acid. The effects of substrates' molar ratios, reaction temperature, reaction time on esterification rates, and Lipozyme 435 reuse were studied. Results showed that an excess of oleic acid (xylose: oleic acid molar ratio of 1:5) significantly favored the reaction, yielding 98% of xylose conversion and 31% oleic acid conversion after 24 h-reaction (mainly to xylose mono- and dioleate, as confirmed by mass spectrometry). The highest Lipozyme 435 activities occurred between 55 and 70 °C. The predicted Ping Pong Bi Bi kinetic model fitted very well to the experimental data and there was no evidence of inhibitions in the range assessed. The reaction product was purified and presented an emulsion capacity close to that of a commercial sugar ester detergent. Finally, the repeated use of Lipozyme 435 showed a reduction in the reaction yields (by 48 and 19% in the xylose and oleic acid conversions, respectively), after ten 12 h-cycles.


Assuntos
Butanonas/química , Lipase/metabolismo , Xilose/química , Biocatálise , Esterificação , Temperatura Alta , Ácido Oleico/química
18.
J Chem Inf Model ; 61(7): 3604-3614, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34251205

RESUMO

Environmentally friendly processes are nowadays a trending topic to get highly desired chemical compounds and, in this sense, the use of enzyme-catalyzed routes is becoming a promising alternative to traditional synthetic methods. In the present paper, a hybrid quantum mechanics/molecular mechanics (QM/MM) computational study on the epoxidation of alkenes catalyzed by the Ser105Ala variant of the promiscuous Candida antarctica lipase B (CALB) is presented in an attempt to search for alternative paths to get useful intermediates in industries. The catalyzed reaction, described at the atomistic level with a model of the full solvated in a box of water molecules, is compared with the alternative epoxidation of alkenes by peroxy acids in chloroform. Free-energy profiles obtained at the density functional theory (DFT)/MM level show how Ser105Ala CALB is capable of epoxide short alkenes in a two-step process with free-energy barriers, in agreement with available experimental data, that are significantly lower than those of the single-step reaction in solution. The possible (R)-enantioselectivity dictated by the binding step, explored by means of alchemical QM/MM free-energy perturbation (FEP) methods, and the preference for the (S)-enantiomer derived from the free-energy landscape of the chemical steps would cancel out, thus predicting the lack of enantioselectivity experimentally observed. In general, our results provide general information on the molecular mechanism employed by a highly promiscuous enzyme, with potential applications in biotechnology.


Assuntos
Compostos de Epóxi , Lipase , Basidiomycota , Proteínas Fúngicas/metabolismo , Lipase/metabolismo , Simulação de Dinâmica Molecular , Estereoisomerismo
19.
Fish Shellfish Immunol ; 116: 52-60, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34216786

RESUMO

The aim of this study was to investigate the effects of dietary bile acids (BAs) on intestinal healthy status of tongue sole in terms of immunity, antioxidant status, digestive ability, mucosal barrier-related genes expression and microbiota. Three experimental diets were prepared with BA levels at 0 mg/kg (CT), 300 mg/kg (BA1) and 900 mg/kg (BA2) in a commercial basal diet. Each diet was fed to three replicates with 120 fish (10.87 ± 0.32 g) in each tank. After an 8-week feeding trial, growth parameters were significantly enhanced in both BAs supplementary groups (P < 0.05), and compared with CT group, survival rate in BA2 group was significantly improved (P < 0.05). Intestinal lysozyme activity and contents of immunoglobulin M and complement 3 were significantly increased in both BAs supplementary groups (P < 0.05), suggesting an enhancement effect on the non-specific immune response. BAs inclusion also significantly improved intestinal antioxidant capabilities by increasing antioxidase activities and decreasing malondialdehyde levels. In addition, compared with CT group, intestinal digestive ability was substantially enhanced as indicated by the significantly increased lipase activity in BA2 group (P < 0.05) and significantly increased amylase activity in BA1 and BA2 groups (P < 0.05). Coincidentally, BAs inclusion significantly upregulated the relative expression of intestinal mucosal barrier-related genes (P < 0.05). Further, dietary BAs distinctly remodeled intestinal microbiota by decreased the abundance of some potential pathogenic bacteria. In conclusion, dietary BAs supplementation is an effective way to improve the intestinal healthy status of tongue sole.


Assuntos
Ácidos e Sais Biliares/farmacologia , Suplementos Nutricionais , Linguados , Microbioma Gastrointestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Fosfatase Alcalina/imunologia , Amilases/metabolismo , Animais , Complemento C3/imunologia , Dieta/veterinária , Proteínas de Peixes/metabolismo , Linguados/genética , Linguados/imunologia , Linguados/metabolismo , Linguados/microbiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Imunoglobulina M/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Lipase/metabolismo , Muramidase/imunologia , Oxirredutases/metabolismo , Peptídeo Hidrolases/metabolismo , Proteínas de Junções Íntimas/genética
20.
Fish Physiol Biochem ; 47(4): 1243-1255, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34226986

RESUMO

The effects of stocking density on growth performance, serum biochemistry, digestive enzymes, immune response, and muscle quality of largemouth bass (Micropterus salmoides) reared in nine in-pond raceway systems (IPRS, 22.0 m × 5.0 m × 2.0 m) were studied. M. salmoides with initial an body weight of 8.25 ± 0.51 g and body length of 6.99 ± 0.44 cm were reared at an initial stocking density of 90.91 ind./m3 (low stocking density, LSD), 113.63 ind./m3 (middle stocking density, MSD), and 136.36 ind./m3 (high stocking density, HSD) with triplication. After 300 days of culture, MSD recorded the highest final body weight, weight gain, specific growth rate, and yield, but the food conversion ratio in MSD was the lowest. The viscerosomatic index in LSD was significantly higher than other groups. The fish serum reared at HSD showed significantly lower total protein, higher total cholesterol, triglyceride, total bilirubin, glucose content, alanine transaminase, and aspartate transaminase activity. Significantly lower intestinal amylase, lipase, trypsin activities, hepatic superoxide dismutase (SOD) and catalase (CAT) activities, and higher malondialdehyde content were detected in HSD compared to others. The content of crude lipid, saturated fatty acid decreased, and total essential amino acid, delicious amino acid, and polyunsaturated fatty acid increased in muscle with stocking density increase. No significant difference was observed in muscle texture. Profitability analysis indicated the benefit-to-cost ratio varied between 1.10 and 1.68, of which MSD was significantly higher than others. The optimal stocking density for M. salmoides should be 113.63 ind./m3 in an IPRS farm.


Assuntos
Aquicultura/métodos , Bass , Alanina Transaminase/sangue , Aminoácidos/metabolismo , Amilases/metabolismo , Animais , Aspartato Aminotransferases/sangue , Bass/sangue , Bass/crescimento & desenvolvimento , Bass/imunologia , Bass/metabolismo , Catalase/metabolismo , Ácidos Graxos/metabolismo , Proteínas de Peixes/sangue , Imunidade , Intestinos/enzimologia , Lipase/metabolismo , Fígado/metabolismo , Músculos/química , Esteróis/sangue , Superóxido Dismutase/metabolismo , Triglicerídeos/sangue , Tripsina/metabolismo
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