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1.
Int J Biol Macromol ; 264(Pt 2): 130730, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462111

RESUMO

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.


Assuntos
Lipase , Nanopartículas de Magnetita , Lipase/química , Enzimas Imobilizadas/química , Óleos de Plantas/química , Esterificação , Estabilidade Enzimática
2.
Int J Biol Macromol ; 264(Pt 2): 130817, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479669

RESUMO

Biosensors with nanomaterials and enzymes detect and quantify specific targets in samples, converting recognition into measurable signals. The study explores the intrinsic synergy between these elements for detecting and quantifying particular targets in biological and environmental samples, with results demonstrated through bibliometric analysis and a comprehensive review of enzyme-based biosensors. Using WoS, 57,331 articles were analyzed and refined to 880. Key journals, countries, institutions, and relevant authors were identified. The main areas highlighted the multidisciplinary nature of the field, and critical keywords identified five thematic clusters, revealing the primary nanoparticles used (CNTs, graphene, AuNPs), major application fields, basic application themes, and niche topics such as sensitive detection, peroxidase activity, and quantum dot utilization. The biosensor overview covered nanomaterials and their primary applications, addressing recent advances and inherent challenges. Patent analysis emphasized the U.S. leadership in the industrial sector, contrasting with China's academic prominence. Future studies should focus on enhancing biosensor portability and analysis speed, with challenges encompassing efficient integration with recent technologies and improving stability and reproducibility in the nanomaterial-enzyme interaction.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanoestruturas , Ouro , Reprodutibilidade dos Testes , Técnicas Biossensoriais/métodos
3.
Int J Biol Macromol ; 253(Pt 3): 126709, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37696372

RESUMO

Magnetic biocatalysts combine magnetic properties with the catalytic activity of enzymes, achieving easy recovery and reuse in biotechnological processes. Lipases immobilized by magnetic nanoparticles dominate. This review covers an advanced bibliometric analysis and an overview of the area, elucidating research advances. Using WoS, 34,949 publications were analyzed and refined to 450. The prominent journals, countries, institutions, and authors that published the most were identified. The most cited articles showed research hotspots. The analysis of the themes and keywords identified five clusters and showed that the main field of research is associated with obtaining biofuels derived from different types of sustainable vegetable oils. The overview of magnetic biocatalysts showed that these materials are also employed in biosensors, photothermal therapy, environmental remediation, and medical applications. The industry shows a significant interest, with the number of patents increasing. Future studies should focus on immobilizing new lipases in unique materials with magnetic profiles, aiming to improve the efficiency for various biotechnological applications.


Assuntos
Enzimas Imobilizadas , Nanopartículas , Lipase , Magnetismo , Fenômenos Magnéticos
4.
J Biomol Struct Dyn ; 41(19): 9282-9296, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36326114

RESUMO

Lantana camara L. (Verbenaceae), commonly called lead cambará, has often been used in folk medicine as antiseptic, antispasmodic, against hemorrhages, flu, colds, and diarrheic. This plant is considered a weed and an ornamental and medicinal plant and is an essential source of natural organic compounds, mainly flavonoids. This work aims to investigate the chemical composition and evaluate the biological properties such as antioxidant and acetylcholinesterase of the constituents from L. camara flowers. In addition, the computational simulation was carried out with the constituents identified. The results showed that methanolic extract of the flowers of L. camara presents toxicity, antioxidant activity with 97.8% inhibition percentage in the concentration of 0.25 mg mL-1 against the DPPH radical, and acetylcholinesterase activity. The phytochemical study of extract from L. camara flowers resulted in LC-MS identification of 18 polyphenolic compounds, such as phenolic acid derivatives, phenylethanoid glycosides, and flavonoids. In the in silico study, flavonoid isoverbascoside showed affinity energy of -9.9 kcal.mol-1 with the AChE enzyme. Their phytochemical content, mainly the presence of flavonoids and phenolic compounds in L. camara extracts, may be related to the antioxidant and anticholinesterase potential observed.


Assuntos
Antioxidantes , Lantana , Antioxidantes/farmacologia , Acetilcolinesterase , Lantana/química , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologia , Flores , Compostos Fitoquímicos/farmacologia , Flavonoides/farmacologia
5.
Int J Biol Macromol ; 141: 313-324, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31491511

RESUMO

The lipase from Pseudomonas fluorescens (PFL) was adsorbed on superparamagnetic NiZnFe2O4 octyl-nanoparticles via interfacial activation, producing the biocatalyst OCTYL-NANO-PFL. In order to further improve the stability of the immobilized lipase, the immobilized enzyme biocatalyst was chemically modified with different concentrations of diverse bifunctional molecules (glutaraldehyde (GA), divinylsulfone (DVS) or p-benzoquinone (BQ)). The concentrations of bifunctional agents were varied (0.5, 1, 2.5 and 5% (v/v for GA and DVS and w/v for BQ)). The results showed a greatly improved stability after chemical modification with all bifunctional molecules, mainly with 5% (v/v) GA or 1% (v/v) DVS. The biocatalysts OCTYL-NANO-PFL-GA 5% and -DVS 1% were about 60 folds more stable at pH 7 than the unmodified preparation and, at pH 5, >200 folds for 5% GA modified enzyme. The most stable BQ treated biocatalysts, OCTYL-NANO-PFL-BQ 0.5%, was about 8.3 more stable than OCTYL-NANO-PFL at pH 7, while was 20 fold more stable at pH 9.


Assuntos
Enzimas Imobilizadas , Lipase/química , Nanopartículas , Octanos , Pseudomonas fluorescens/enzimologia , Biocatálise , Ativação Enzimática , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Nanopartículas/química , Nanopartículas/ultraestrutura , Octanos/química , Análise Espectral
6.
Int J Biol Macromol ; 134: 936-945, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31121223

RESUMO

NiZnFe2O4 superparamagnetic nanoparticles were coated with silica by impregnation with tetraethoxysilane (TEOS) and further activated with divinylsulfone (DVS) and p-benzoquinone (BQ) for covalent immobilization lipase from Pseudomonas fluorescens (PFL), producing the biocatalysts TEOS-NANO-DVS-PFL and TEOS-NANO-BQ-PFL. The optimal conditions for enzyme immobilization were found to be pH 7 and 0.1 M of both activating reagents. PFL was also immobilized on TEOS nanoparticles without any activation as a reference (TEOS-NANO-PFL). Results indicated that TEOS could be released from the nanoparticles at alkaline pH value. Optimal TEOS-NANO-PFL exhibited a recovered activity of 55% and a t1/2(60°C) of just over 150 min; while TEOS-NANO-DVS-PFL showed 82% of activity recovered and t1/2(60°C) of 225 min; being the TEOS-NANO-BQ-PFL the biocatalyst offering the best results (89% of recovered activity and a half-life over 1440 min), the maximum enzyme load was ≈300 U/g.


Assuntos
Benzoquinonas/química , Enzimas Imobilizadas , Lipase/química , Pseudomonas fluorescens/enzimologia , Sulfonas/química , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/química , Modelos Moleculares , Conformação Proteica , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
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