Assessing the Effect of Deep Eutectic Solvents on α-Chymotrypsin Thermal Stability and Activity.

Optimizing the liquid reaction phase holds significant potential for enhancing the efficiency of biocatalytic processes since it determines reaction equilibrium and kinetics. This study investigates the influence of the addition of deep eutectic solvents on the stability and activity of α-chymotrypsin, a proteolytic enzyme with industrial relevance. Deep eutectic solvents, composed of choline chloride or betaine mixed with glycerol or sorbitol, were added in the reaction phase at various concentrations.

Assessing the Influence of Betaine-Based Natural Deep Eutectic Systems on Horseradish Peroxidase.

To validate the use of horseradish peroxidase (HRP) in natural deep eutectic systems (NADES), five different betaine-based NADES were characterized in terms of water content, water activity, density, and viscosity experimentally and by thermodynamic modeling. The results show that the NADES under study have a water activity of about 0.4 at 37 °C for water contents between 14 and 22 wt %.

Osmolyte effect on enzymatic stability and reaction equilibrium of formate dehydrogenase.

Osmolytes are well-known biocatalyst stabilisers as they promote the folded state of proteins, and a stabilised biocatalyst might also improve reaction kinetics. In this work, the influence of four osmolytes (betaine, glycerol, trehalose, and trimethylamine -oxide) on the activity and stability of formate dehydrogenase FDH was studied experimentally and theoretically. Scanning differential fluorimetric studies were performed to assess the thermal stability of FDH, while UV detection was used to reveal changes in FDH activity and reaction equilibrium at osmolyte concentrations between 0.

Boosting the kinetic efficiency of formate dehydrogenase by combining the effects of temperature, high pressure and co-solvent mixtures.

The application of co-solvents and high pressure has been shown to be an efficient means to modify the kinetics of enzyme-catalyzed reactions without compromising enzyme stability, which is often limited by temperature modulation. In this work, the high-pressure stopped-flow methodology was applied in conjunction with fast UV/Vis detection to investigate kinetic parameters of formate dehydrogenase reaction (FDH), which is used in biotechnology for cofactor recycling systems. Complementary FTIR spectroscopic and differential scanning fluorimetric studies were performed to reveal pressure and temperature effects on the structure and stability of the FDH.