A kinetic analysis of catalytic production of oxygen in catalase‐containing liposome dispersions for controlled transfer of oxygen in a bioreactor

Abstract

BACKGROUND: Biochemical oxidation reactions require oxygen to be supplied by dispersed bubbles. Drawbacks of the gas-liquid system are enzyme denaturation and low oxygen utilization efficiency. Therefore, oxygen production through the decomposition of H 2 O 2 is useful for controlled oxygen transfer in bioreactors. RESULTS:Catalase-containing liposomes (CALs) were prepared in 50 mmol L -1 Tris/0.1 mol L -1 NaCl buffer (pH 7.4) and the kinetic model was developed for the oxygen production by CAL-catalyzed decomposition of 1.0 mmol L -1 H 2 O 2 . Applying the model to the observed time course of oxygen produced gave overall resistance in the reaction based on the pseudo-steadystate assumption inside liposomes for H 2 O 2 and oxygen. The reaction resistance was estimated with the liposomal catalase concentration e t,in and the kinetic parameters of free enzyme reaction. At e t,in = 0.59 μmol L -1 , the CAL reaction proceeded under reaction control, while at e t,in = 5.05 μmol L -1 , the H 2 O 2 transfer resistance was involved. For the latter case, the permeability coefficient P P of H 2 O 2 through the liposome membrane was determined as 1.06 × 10 -6 m s -1 at 25 • C. The model predicted the H 2 O 2 concentration inside liposomes with different e t,in values. Furthermore, the oxygen concentration in the CAL dispersions was reasonably simulated. The oxygen production rate could be altered based on temperature (10-55 • C) and the fractional volume of CALs. CONCLUSION: The CAL-catalyzed oxygen production was controlled based on the e t,in and P P values, which determine the relative importance of the reaction and H 2 O 2 transfer resistances. The CAL would be applied to oxidation reactions instead of gas-liquid systems.

Coupling Enzymes and Inorganic Piezoelectric Materials for Electricity Production from Renewable Fuels

“…The oxygen replenishment performed by catalase is described in several works. 33,34 In order to demonstrate this effect in our system, we measured the displaced gas volume when catalase/GOX decomposes 50 mM H 2 O 2 in the presence and absence of 300 mM of glucose. The displaced volume was 3.7 times higher when glucose was added to the system (0.14 and 0.56 mL with or without glucose, respectively), thus demonstrating higher oxygen production.…”

Study of the Interaction of a Novel Semi-Synthetic Peptide with Model Lipid Membranes

“…The HRPC molecules cannot cross the membrane due to their large size, and ABTS 2− molecules cannot move from the external bulk solution into the interior of the vesicles due to their negative charge. On the contrary, H 2 O 2 , being small and uncharged, can easily permeate across fluid phospholipid bilayers [ 47 ]. The release of HRPC from the LUVs and/or the uptake of ABTS 2− by the LUVs after peptide addition can be conveniently monitored by UV-vis spectrophotometry as the HRPC-catalysed oxidation of ABTS 2− to ABTS •− results in increased absorbance (see Figure 6 for a schematic representation of the permeability assay).…”

Process intensification for O2‐dependent enzymatic transformations in continuous single‐phase pressurized flow

“…Chapman et al () suggested that one might eliminate the requirement for gas–liquid transport through the in situ generation of O 2 from H 2 O 2 . A number of studies before Chapman et al () have elaborated on the concept (Bolivar, Schelch, et al, ; Schneider, Dorscheid, Witte, Giffhorn, & Heinzle, ; Van Hecke et al, ; Yoshimoto & Higa, ). To overcome the limit of OTR at ambient pressure (for use at high pressure, see Figures and ), the H 2 O 2 ‐based oxygenation would have to be performed strictly under conditions of rate‐limiting formation of O 2 (Bolivar, Schelch, et al, ).…”

“…Catalyst productivity b (g product/g enzyme) STY (g/[L·hr]) X = 0.1 X = 0.9 X = 0.1 X = 0.9 X = 0.1 X = 0.9 (2018) have elaborated on the concept (Bolivar, Schelch, et al, 2016;Schneider, Dorscheid, Witte, Giffhorn, & Heinzle, 2012;Van Hecke et al, 2009;Yoshimoto & Higa, 2014). To overcome the limit of OTR at ambient pressure (for use at high pressure, see Figures 2 and 3), the H 2 O 2 -based oxygenation would have to be performed strictly under conditions of rate-limiting formation of O 2 (Bolivar, Schelch, et al, 2016).…”