In-line quantification of peroxidase-catalyzed cross-linking of α-lactalbumin in a microreactor

Heijnis, Walter H.; Wierenga, Peter A.; Janssen, A.E.M.; Berkel, Willem J.H. van; Gruppen, Harry

doi:10.1016/j.cej.2009.12.001

Cited by 14 publications

(14 citation statements)

References 16 publications

(19 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…15 We have previously considered the initial stages of the oxidative cross-linking of a-lactalbumin catalyzed by horseradish peroxidase, under the periodic addition of peroxide. 6,[16][17][18] As compared to other oxidative enzymes that use dissolved oxygen, the horseradish peroxidase system is a convenient model system since the peroxide concentration is tuned more easily than the concentration of dissolved oxygen. For eventual industrial applications other oxidative enzymes are probably better, since the peroxidase enzyme is inactivated rather quickly by excess peroxide.…”

Section: Introductionmentioning

confidence: 99%

Protein cluster formation during enzymatic cross-linking of globular proteins

et al. 2012

View full text Add to dashboard Cite

Work on enzymatic cross-linking of globular food proteins has mainly focused on food functional effects such as improvements of gelation and enhanced stabilization of emulsions and foams, and on the detailed biochemical characterization of the cross-linking chemistry. What is still lacking is a physical characterization of cluster formation and gelation, as has been done for example, for cluster formation and gelation during heat-induced protein aggregation. Here we present preliminary results along these lines. We propose that enzymatic cross-linking of apo-alpha-lactalbumin is a good model system for studying the problem of cluster formation and gelation during enzymatic cross-linking of globular proteins. We present initial results on cluster sizes produced when crosslinking dilute solutions of apo-alpha-lactalbumin with a range of cross-linking enzymes: microbial transglutaminase, horseradish peroxidase, and mushroom tyrosinase. These results are used to highlight similarities and differences between different enzymes, when acting on the same substrate. Next we consider cluster growth and gelation in somewhat more detail for the specific case of cross-linking by horseradish peroxidase, under the periodic addition of H2O2. Upon increasing the initial concentration of apo-alpha-lactalbumin, at a fixed enzyme-to-substrate ratio and fixed reaction time, the size of the clusters at the end of the reaction increases rapidly, and above a critical concentration, gelation occurs. For the conditions that we have used, gelation occurred at very low initial apo-alpha-lactalbumin concentrations of 34% (w/v), indicating a very dilute cross-linked protein network, with a low average number of cross-links per protein. It is found that reactive protein monomers are first rapidly (1-2 h) incorporated into small covalent clusters. This is followed by a much slower phase (up to about 12 h) in which the small clusters are coupled together to form much larger covalent protein clusters. Consistent with this two-step mechanism, atomic force microscopy shows that the covalent protein clusters are very heterogeneous and seem to consist of smaller subclusters.

show abstract

Section: Introductionmentioning

confidence: 99%

Protein cluster formation during enzymatic cross-linking of globular proteins

et al. 2012

View full text Add to dashboard Cite

show abstract

“…The enzyme catalysis was based on the previous literature. In the horseradish peroxidase catalysis condition, 100 U/ml of enzyme was added at 40°C and mixed for 2 hr at pH 5.0 with H 2 O 2 1 mmol/L (Heijnis et al., 2010). In the tyrosinase catalysis conditions, 450 U/ml enzyme was added at 50°C and mixed for 3 hr at pH 7.0 with 1 mmol/L of caffeic acid (Thalmann & Lötzbeyer, 2002).…”

Section: Methodsmentioning

confidence: 99%

The effect of composite enzyme catalysis whey protein cross‐linking on filtration performance

Wang

Ji‐yang

Qian

et al. 2021

Food Science & Nutrition

View full text Add to dashboard Cite

In this study, enzymatic cross‐linked whey protein coupling ultrafiltration was used to reduce membrane fouling and increase whey protein recovery rate. The filtration efficiency and protein interaction with the membrane surface were investigated. The results showed that the protein recovery rate and relative flux of transglutaminase catalysis protein followed by tyrosinase each increased by approximately 30% during ultrafiltration. The total membrane resistance was reduced by approximately 20%. The shape of the transglutaminase and tyrosinase cross‐linked protein had somewhat spherical and cylindrical structure similar to an elongated shape based on fluorescence microscopy imaging, which indicated membrane resistance reduction. Fluorescence excitation–emission matrix spectroscopy (EEM) showed that the permeation peak intensities of transglutaminase followed by tyrosinase catalysis protein decreased sharply in the tryptophan and aromatic‐like protein fields, indicating that most protein was rejected after ultrafiltration. The repulsive interaction energy was increased between the cross‐linked proteins and membrane based on extended Derjaguin–Landau–Verwey–Overbeek (XDLVO) analysis.

show abstract

“…Heijnis and co-workers developed a setup anchored in a Y-shaped commercial microchip to study the cross-linking of α-lactalbumin with horseradish peroxidase (HRP) [ 153 ]. Hydrogen peroxide, α-lactalbumin and HRP were loaded into the microchannel using a syringe pump and the evolution of the reaction was monitored using a UV-detector connected in-line with the microreactor.…”

Section: Application Of Microstructured Devices To Bioprocesses: Smentioning

confidence: 99%

“…Microreactors have been used as scale-down system for complex enzymatic synthesis, such as multienzyme catalysis, cascade reactions, rapid characterization of bioconversion processes and design of microfluidic biofuel cells [ 12 , 153 , 154 , 155 , 156 ]. The application of microstructured reactors in such bioconversion processes is often associated with the use of immobilized enzymes.…”

Section: Application Of Microstructured Devices To Bioprocesses: Smentioning

confidence: 99%

Microfluidic Devices: Useful Tools for Bioprocess Intensification

Marques

Fernandes

2011

Molecules

View full text Add to dashboard Cite

The dawn of the new millennium saw a trend towards the dedicated use of microfluidic devices for process intensification in biotechnology. As the last decade went by, it became evident that this pattern was not a short-lived fad, since the deliverables related to this field of research have been consistently piling-up. The application of process intensification in biotechnology is therefore seemingly catching up with the trend already observed in the chemical engineering area, where the use of microfluidic devices has already been upgraded to production scale. The goal of the present work is therefore to provide an updated overview of the developments centered on the use of microfluidic devices for process intensification in biotechnology. Within such scope, particular focus will be given to different designs, configurations and modes of operation of microreactors, but reference to similar features regarding microfluidic devices in downstream processing will not be overlooked. Engineering considerations and fluid dynamics issues, namely related to the characterization of flow in microchannels, promotion of micromixing and predictive tools, will also be addressed, as well as reflection on the analytics required to take full advantage of the possibilities provided by microfluidic devices in process intensification. Strategies developed to ease the implementation of experimental set-ups anchored in the use of microfluidic devices will be briefly tackled. Finally, realistic considerations on the current advantages and limitation on the use of microfluidic devices for process intensification, as well as prospective near future developments in the field, will be presented.

show abstract

In-line quantification of peroxidase-catalyzed cross-linking of α-lactalbumin in a microreactor

Cited by 14 publications

References 16 publications

Protein cluster formation during enzymatic cross-linking of globular proteins

Protein cluster formation during enzymatic cross-linking of globular proteins

The effect of composite enzyme catalysis whey protein cross‐linking on filtration performance

Microfluidic Devices: Useful Tools for Bioprocess Intensification

Contact Info

Product

Resources

About