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Tacias-Pascacio VG, Castañeda-Valbuena D, Tavano O, Abellanas-Perez P, de Andrades D, Santiz-Gómez JA, Berenguer-Murcia Á, Fernandez-Lafuente R. A review on the immobilization of bromelain. Int J Biol Macromol 2024; 273:133089. [PMID: 38878936 DOI: 10.1016/j.ijbiomac.2024.133089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 05/21/2024] [Accepted: 06/09/2024] [Indexed: 06/24/2024]
Abstract
This review shows the endeavors performed to prepare immobilized formulations of bromelain extract, usually from pineapple, and their use in diverse applications. This extract has a potent proteolytic component that is based on thiol proteases, which differ depending on the location on the fruit. Stem and fruit are the areas where higher activity is found. The edible origin of this enzyme is one of the features that determines the applications of the immobilized bromelain to a more significant degree. The enzyme has been immobilized on a wide diversity of supports via different strategies (covalent bonds, ion exchange), and also forming ex novo solids (nanoflowers, CLEAs, trapping in alginate beads, etc.). The use of preexisting nanoparticles as immobilization supports is relevant, as this facilitates one of the main applications of the immobilized enzyme, in therapeutic applications (as wound dressing and healing components, antibacterial or anticancer, mucus mobility control, etc.). A curiosity is the immobilization of this enzyme on spores of probiotic microorganisms via adsorption, in order to have a perfect in vivo compatibility. Other outstanding applications of the immobilized enzyme are in the stabilization of wine versus haze during storage, mainly when immobilized on chitosan. Curiously, the immobilized bromelain has been scarcely applied in the production of bioactive peptides.
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Affiliation(s)
- Veymar G Tacias-Pascacio
- Facultad de Ciencias de la Nutrición y Alimentos, Universidad de Ciencias y Artes de Chiapas, Lib. Norte Pte. 1150, 29039 Tuxtla Gutiérrez, Chiapas, Mexico.
| | - Daniel Castañeda-Valbuena
- Facultad de Ciencias de la Nutrición y Alimentos, Universidad de Ciencias y Artes de Chiapas, Lib. Norte Pte. 1150, 29039 Tuxtla Gutiérrez, Chiapas, Mexico
| | - Olga Tavano
- Faculty of Nutrition, Alfenas Federal Univ., 700 Gabriel Monteiro da Silva St, Alfenas, MG 37130-000, Brazil
| | | | - Diandra de Andrades
- Departamento de Biocatálisis, ICP-CSIC, Campus UAM-CSIC, Madrid, Spain; Department of Biology, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-901, SP, Brazil
| | - José Alfredo Santiz-Gómez
- Tecnológico Nacional de México/Instituto Tecnológico de Tuxtla Gutiérrez, Carretera Panamericana Km. 1080, 29050 Tuxtla Gutiérrez, Chiapas, Mexico
| | - Ángel Berenguer-Murcia
- Departamento de Química Inorgánica e Instituto Universitario de Materiales, Universidad de Alicante, Alicante, Spain
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Xu W, Zhang X, Ni D, Zhang W, Guang C, Mu W. A review of fructosyl-transferases from catalytic characteristics and structural features to reaction mechanisms and product specificity. Food Chem 2024; 440:138250. [PMID: 38154282 DOI: 10.1016/j.foodchem.2023.138250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 12/30/2023]
Abstract
Carbohydrate-active enzymes are accountable for the synthesis and degradation of glycosidic bonds among diverse carbohydrates. Fructosyl-transferases represent a subclass of these enzymes, employing sucrose as a substrate to generate fructooligosaccharides (FOS) and fructan polymers. This category primarily includes levansucrase (LS, EC 2.4.1.10), inulosucrase (IS, EC 2.4.1.9), and β-fructofuranosidase (Ffase, EC 3.2.1.26). These three enzymes possess a similar five-bladed β-propeller fold and employ an anomer-retaining reaction mechanism mediated by nucleophiles, transition state stabilizers, and general acids/bases. However, they exhibit distinct product profiles, characterized by variations in linkage specificity and molecular mass distribution. Consequently, this article comprehensively explores recent advancements in the catalytic characteristics, structural features, reaction mechanisms, and product specificity of levansucrase, inulosucrase, and β-fructofuranosidase (abbreviated as LS, IS, and Ffase, respectively). Furthermore, it discusses the potential for modifying catalytic properties and product specificity through structure-based design, which enables the rational production of custom fructan and FOS.
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Affiliation(s)
- Wei Xu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Xiaoqi Zhang
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Dawei Ni
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Cuie Guang
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China.
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Isomelezitose Overproduction by Alginate-Entrapped Recombinant E. coli Cells and In Vitro Evaluation of Its Potential Prebiotic Effect. Int J Mol Sci 2022; 23:ijms232012682. [PMID: 36293535 PMCID: PMC9604484 DOI: 10.3390/ijms232012682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 10/11/2022] [Accepted: 10/18/2022] [Indexed: 11/04/2022] Open
Abstract
In this work, the trisaccharide isomelezitose was overproduced from sucrose using a biocatalyst based on immobilized Escherichia coli cells harbouring the α-glucosidase from the yeast Metschnikowia reukaufii, the best native producer of this sugar described to date. The overall process for isomelezitose production and purification was performed in three simple steps: (i) oligosaccharides synthesis by alginate-entrapped E. coli; (ii) elimination of monosaccharides (glucose and fructose) using alginate-entrapped Komagataella phaffii cells; and (iii) semi-preparative high performance liquid chromatography under isocratic conditions. As result, approximately 2.15 g of isomelezitose (purity exceeding 95%) was obtained from 15 g of sucrose. The potential prebiotic effect of this sugar on probiotic bacteria (Lactobacillus casei, Lactobacillus rhamnosus and Enterococcus faecium) was analysed using in vitro assays for the first time. The growth of all probiotic bacteria cultures supplemented with isomelezitose was significantly improved and was similar to that of cultures supplemented with a commercial mixture of fructo-oligosaccharides. In addition, when isomelezitose was added to the bacteria cultures, the production of organic acids (mainly butyrate) was significantly promoted. Therefore, these results confirm that isomelezitose is a potential novel prebiotic that could be included in healthier foodstuffs designed for human gastrointestinal balance maintenance.
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Small tools for sweet challenges: advances in microfluidic technologies for glycan synthesis. Anal Bioanal Chem 2022; 414:5139-5163. [PMID: 35199190 DOI: 10.1007/s00216-022-03948-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 01/26/2022] [Accepted: 01/31/2022] [Indexed: 11/01/2022]
Abstract
Glycans, including oligosaccharides and glycoconjugates, play an integral role in modulating the biological functions of macromolecules. Many physiological and pathological processes are mediated by interactions between glycans, which has led to the use of glycans as biosensors for pathogen and biomarker detection. Elucidating the relationship between glycan structure and biological function is critical for advancing our understanding of the impact glycans have on human health and disease and for expanding the repertoire of glycans available for bioanalysis, especially for diagnostics. Such efforts have been limited by the difficulty in obtaining sufficient quantities of homogenous glycan samples needed to resolve the exact relationships between glycan structure and their structural or modulatory functions on a given glycoconjugate. Synthetic strategies offer a viable route for overcoming these technical hurdles. In recent years, microfluidics have emerged as powerful tools for realizing high-throughput and reproducible syntheses of homogenous glycans for the potential use in functional studies. This critical review provides readers with an overview of the microfluidic technologies that have been developed for chemical and enzymatic glycan synthesis. The advantages and limitations associated with using microreactor platforms to improve the scalability, productivity, and selectivity of glycosylation reactions will be discussed, as well as suggested future work that can address certain pitfalls.
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Enzymatic Synthesis and Characterization of Different Families of Chitooligosaccharides and Their Bioactive Properties. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11073212] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Chitooligosaccharides (COS) are homo- or hetero-oligomers of D-glucosamine (GlcN) and N-acetyl-D-glucosamine (GlcNAc) that can be obtained by chitosan or chitin hydrolysis. Their enzymatic production is preferred over other methodologies (physical, chemical, etc.) due to the mild conditions required, the fewer amounts of waste and its efficiency to control product composition. By properly selecting the enzyme (chitinase, chitosanase or nonspecific enzymes) and the substrate properties (degree of deacetylation, molecular weight, etc.), it is possible to direct the synthesis towards any of the three COS types: fully acetylated (faCOS), partially acetylated (paCOS) and fully deacetylated (fdCOS). In this article, we review the main strategies to steer the COS production towards a specific group. The chemical characterization of COS by advanced techniques, e.g., high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) and MALDI-TOF mass spectrometry, is critical for structure–function studies. The scaling of processes to synthesize specific COS mixtures is difficult due to the low solubility of chitin/chitosan, the heterogeneity of the reaction mixtures, and high amounts of salts. Enzyme immobilization can help to minimize such hurdles. The main bioactive properties of COS are herein reviewed. Finally, the anti-inflammatory activity of three COS mixtures was assayed in murine macrophages after stimulation with lipopolysaccharides.
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Ni D, Xu W, Zhu Y, Pang X, Lv J, Mu W. Insight into the effects and biotechnological production of kestoses, the smallest fructooligosaccharides. Crit Rev Biotechnol 2020; 41:34-46. [PMID: 33153319 DOI: 10.1080/07388551.2020.1844622] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Kestoses, the smallest fructooligosaccharides, are trisaccharides composed of a fructose molecule and a sucrose molecule linked by either β-(2,1) or β-(2,6) linkage. 1-kestose, 6-kestose and neokestose are the three types of kestoses occurring in nature. As the main kind of fructooligosaccharide, kestoses share similar physiological effects with other fructooligosaccharides, and they have recently been determined to show more notable effects in promoting the growth of probiotics including Faecalibacterium prausnitzii and Bifidobacterium than those of other fructooligosaccharides. Kestoses exist in many plants, but the relatively low content and the isolation and purification are the main barriers limiting their industrial application. The production of kestoses by enzymatic biosynthesis and microbial fermentation has the potential to facilitate its production and industrial use. In this article, the recent advances in the research of kestoses were overviewed, including those studying their functions and production. Kestose-producing enzymes were introduced in detail, and microbial production and fermentation optimization techniques for enhancing the yield of kestoses were addressed. β-Fructofuranosidase is the main one used to produce kestoses because of the extensive range of microbial sources. Therefore, the production of kestoses by microorganisms containing β-fructofuranosidase has also been reviewed. However, few molecular modification studies have attempted to change the production profile of some enzymes and improve the yield of kestoses, which is a topic that should garner more attention. Additionally, the production of kestoses using food-grade microorganisms may be beneficial to their application in the food industry.
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Affiliation(s)
- Dawei Ni
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Wei Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Yingying Zhu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Xiaoyang Pang
- Key Laboratory of Agro-Products Processing, Ministry of Agriculture and Rural Affairs/Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jiaping Lv
- Key Laboratory of Agro-Products Processing, Ministry of Agriculture and Rural Affairs/Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
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Neifar S, Cervantes FV, Bouanane-Darenfed A, BenHlima H, Ballesteros AO, Plou FJ, Bejar S. Immobilization of the glucose isomerase from Caldicoprobacter algeriensis on Sepabeads EC-HA and its efficient application in continuous High Fructose Syrup production using packed bed reactor. Food Chem 2020; 309:125710. [DOI: 10.1016/j.foodchem.2019.125710] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 10/10/2019] [Accepted: 10/14/2019] [Indexed: 01/26/2023]
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Deciphering the molecular specificity of phenolic compounds as inhibitors or glycosyl acceptors of β-fructofuranosidase from Xanthophyllomyces dendrorhous. Sci Rep 2019; 9:17441. [PMID: 31767902 PMCID: PMC6877581 DOI: 10.1038/s41598-019-53948-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 09/12/2019] [Indexed: 01/09/2023] Open
Abstract
Enzymatic glycosylation of polyphenols is a tool to improve their physicochemical properties and bioavailability. On the other hand, glycosidic enzymes can be inhibited by phenolic compounds. In this work, we studied the specificity of various phenolics (hydroquinone, hydroxytyrosol, epigallocatechin gallate, catechol and p-nitrophenol) as fructosyl acceptors or inhibitors of the β-fructofuranosidase from Xanthophyllomyces dendrorhous (pXd-INV). Only hydroquinone and hydroxytyrosol gave rise to the formation of glycosylated products. For the rest, an inhibitory effect on both the hydrolytic (H) and transglycosylation (T) activity of pXd-INV, as well as an increase in the H/T ratio, was observed. To disclose the binding mode of each compound and elucidate the molecular features determining its acceptor or inhibitor behaviour, ternary complexes of the inactive mutant pXd-INV-D80A with fructose and the different polyphenols were analyzed by X-ray crystallography. All the compounds bind by stacking against Trp105 and locate one of their phenolic hydroxyls making a polar linkage to the fructose O2 at 3.6–3.8 Å from the C2, which could enable the ulterior nucleophilic attack leading to transfructosylation. Binding of hydroquinone was further investigated by soaking in absence of fructose, showing a flexible site that likely allows productive motion of the intermediates. Therefore, the acceptor capacity of the different polyphenols seems mediated by their ability to make flexible polar links with the protein, this flexibility being essential for the transfructosylation reaction to proceed. Finally, the binding affinity of the phenolic compounds was explained based on the two sites previously reported for pXd-INV.
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Two-Step Production of Neofructo-Oligosaccharides Using Immobilized Heterologous Aspergillus terreus 1F-Fructosyltransferase Expressed in Kluyveromyces lactis and Native Xanthophyllomyces dendrorhous G6-Fructosyltransferase. Catalysts 2019. [DOI: 10.3390/catal9080673] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Fructo-oligosaccharides (FOS) are prebiotic low-calorie sweeteners that are synthesized by the transfer of fructose units from sucrose by enzymes known as fructosyltransferases. If these enzymes generate β-(2,6) glycosidic bonds, the resulting oligosaccharides belong to the neoseries (neoFOS). Here, we characterized the properties of three different fructosyltransferases using a design of experiments approach based on response surface methodology with a D-optimal design. The reaction time, pH, temperature, and substrate concentration were used as parameters to predict three responses: The total enzyme activity, the concentration of neoFOS and the neoFOS yield relative to the initial concentration of sucrose. We also conducted immobilization studies to establish a cascade reaction for neoFOS production with two different fructosyltransferases, achieving a total FOS yield of 47.02 ± 3.02%. The resulting FOS mixture included 53.07 ± 1.66 mM neonystose (neo-GF3) and 20.8 ± 1.91 mM neo-GF4.
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Abstract
Immobilization techniques are generally based on reusing enzymes in industrial applications to reduce costs and improve enzyme properties. These techniques have been developing for decades, and many methods for immobilizing enzymes have been designed. To find a better immobilization method, it is necessary to review the recently developed methods and have a clear overview of the advantages and limitations of each method. This review introduces the recently reported immobilization methods and discusses the improvements in enzyme properties by different methods. Among the techniques to improve enzyme properties, metal–organic frameworks, which have diverse structures, abundant organic ligands and metal nodes, offer a promising platform.
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Choukade R, Kango N. Characterization of a mycelial fructosyltransferase from Aspergillus tamarii NKRC 1229 for efficient synthesis of fructooligosaccharides. Food Chem 2019; 286:434-440. [PMID: 30827630 DOI: 10.1016/j.foodchem.2019.02.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 02/04/2019] [Accepted: 02/06/2019] [Indexed: 01/09/2023]
Abstract
An efficient system for biotransformation of sucrose to fructooligosaccharides (FOS) was obtained using Aspergillus tamarii NKRC 1229 mycelial fructosyltransferase (m-FTase). Zymographic analysis confirmed mycelial localization of the FTase (36 U/g) and lyophilized fungal pellets were used for bioconversion. m-FTase had molecular weight ∼75 kDa with optimum activity at pH 7.0 and 20 °C. FOS production after parametric optimization (sucrose - 50% w/v, m-FTase dose - 4.5% w/v, inoculum age - 48 h and incubation time - 24 h) reached 325 g/L (55% yield) with 14% residual sucrose, 25% glucose and 6% fructose. FTase activity was enhanced after pre-treatment with organic solvents and SDS. FOS was purified in a single step using gel filtration matrix, Bio-Gel P2. FOS was characterized using Diffusion ordered spectroscopy-Nuclear Magnetic Resonance (1H DOSY-NMR) and Fourier-transform infrared spectroscopy (FTIR). Continuous generation of FOS was achieved using recyclable mycelia upto 10 consecutive cycles.
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Affiliation(s)
- Ritumbhara Choukade
- Enzyme Technology and Molecular Catalysis Laboratory, Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, Madhya Pradesh 470003, India.
| | - Naveen Kango
- Enzyme Technology and Molecular Catalysis Laboratory, Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, Madhya Pradesh 470003, India.
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Míguez N, Ramírez‐Escudero M, Gimeno‐Pérez M, Poveda A, Jiménez‐Barbero J, Ballesteros AO, Fernández‐Lobato M, Sanz‐Aparicio J, Plou FJ. Fructosylation of Hydroxytyrosol by the β‐Fructofuranosidase from
Xanthophyllomyces dendrorhous
: Insights into the Molecular Basis of the Enzyme Specificity. ChemCatChem 2018. [DOI: 10.1002/cctc.201801171] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Noa Míguez
- Biocatalysis DepartmentInstitute of Catalysis and Petrochemistry (CSIC) Madrid 28049 Spain
| | - Mercedes Ramírez‐Escudero
- Macromolecular Crystallography and Structural Biology Department Institute of Physical-Chemistry Rocasolano (CSIC) Madrid 28006 Spain
| | - María Gimeno‐Pérez
- Molecular Biology Department Centre of Molecular Biology Severo Ochoa (CSIC-UAM)Autonomous University of Madrid Madrid 28049 Spain
| | - Ana Poveda
- CIC bioGUNE: Center for Cooperative Research in Biosciences Basque Network of Science Technology and InnovationBiscay Science and Technology Park Derio 48160 Spain
| | - Jesús Jiménez‐Barbero
- CIC bioGUNE: Center for Cooperative Research in Biosciences Basque Network of Science Technology and InnovationBiscay Science and Technology Park Derio 48160 Spain
| | - Antonio O. Ballesteros
- Biocatalysis DepartmentInstitute of Catalysis and Petrochemistry (CSIC) Madrid 28049 Spain
| | - María Fernández‐Lobato
- Molecular Biology Department Centre of Molecular Biology Severo Ochoa (CSIC-UAM)Autonomous University of Madrid Madrid 28049 Spain
| | - Julia Sanz‐Aparicio
- Macromolecular Crystallography and Structural Biology Department Institute of Physical-Chemistry Rocasolano (CSIC) Madrid 28006 Spain
| | - Francisco J. Plou
- Biocatalysis DepartmentInstitute of Catalysis and Petrochemistry (CSIC) Madrid 28049 Spain
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Jing X, Peng X, Cao Y, Wang W, Wang S. Enhanced photocarriers separation of novel CdS/pt/Mo 2C heterostructure for visible-light-driven hydrogen evolution. RSC Adv 2018; 8:33993-33999. [PMID: 35548809 PMCID: PMC9086742 DOI: 10.1039/c8ra05473h] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 09/12/2018] [Indexed: 11/25/2022] Open
Abstract
The production of H2 from water using photocatalysts is a promising way of generating clean, renewable and alternative energy. The key issue is to develop active and stable photocatalysts. Here, we report a novel CdS/Pt/Mo2C heterostructure photocatalyst, where Pt nanoparticles are closely supported on CdS/Mo2C. The UV-vis spectrum and EIS Nyquist plots show that Mo2C can boost the absorption in the UV-vis region and improve the separation of the photogenerated electron-hole pairs from CdS. The Pt nanoparticles act as the active co-catalyst that promotes the transient photocurrent response. As a result, the CdS/Pt/Mo2C photocatalyst exhibits an excellent H2 evolution activity up to 1828.82 μmol h-1 g-1 under visible-light irradiation, 8.5 and 16.2 times higher than that of pristine CdS and CdS/Mo2C, respectively. Moreover, a high apparent quantum yield (AQY) of 9.39% is obtained at 400 nm for the CdS/Pt/Mo2C heterostructure photocatalyst.
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Affiliation(s)
- Xinbo Jing
- School of Chemistry and Chemical Engineering, Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Shihezi University Shihezi 832000 China
| | - Xueying Peng
- School of Chemistry and Chemical Engineering, Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Shihezi University Shihezi 832000 China
| | - Youzhi Cao
- School of Chemistry and Chemical Engineering, Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Shihezi University Shihezi 832000 China
| | - Wei Wang
- School of Chemistry and Chemical Engineering, Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Shihezi University Shihezi 832000 China
| | - Shufen Wang
- College of Sciences, Shihezi University Shihezi 832000 China
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14
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Abstract
An application-related definition for immobilized enzymes was given by Chibata in 1978 […]
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15
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An Improved Method to Encapsulate Laccase from Trametes versicolor with Enhanced Stability and Catalytic Activity. Catalysts 2018. [DOI: 10.3390/catal8070286] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
In this work, laccase from Trametes versicolor pretreated with copper ion solution was entrapped in copper alginate beads. The presence of laccase in copper alginate beads was verified by Fourier transform infrared (FTIR) spectroscopy. The alginate concentration used was optimized based on the specific activity and immobilization yield. After entrapment, laccase presents perfect pH stability and thermal stability with 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) as the substrate. Moreover, laccase in copper alginate beads exhibits good reusability during continuous batch operation for removing 2,4-dichlorophenol. More importantly, owing to the coupled effect of copper ion activation and copper alginate entrapment, the entrapped laccase shows a 3.0-fold and a 2.4-fold increase in specific activity and 2,4-DCP degradation rate compared with that of free laccase, respectively.
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