Diffusional limitations of anaerobic biofilms

Using an empirical determination of apparent kinetic parameters in the bulk mixed liquor, the intrinsic kinetic parameters of anaerobic biofilms developed at 35 °C during start-up and steady-state downflow stationary fixed film reactor operation were estimated. The apparent kinetic parameters of anaerobic biofilms are not significantly influenced by internal diffusion limitations. The apparent kinetic parameters of mature biofilms showed no significant trends with increased biofilm thickness up to 2.6 mm and increased apparent Thiele modulus up to 3.1. Key words: anaerobic, biofilm kinetics, Thiele modulus, wastewater, filter.

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Kinetic Analysis of R-Selective ω-Transaminases for Determination of Intrinsic Kinetic Parameters and Computational Modeling of Kinetic Resolution of Chiral Amine

Applied Biochemistry and Biotechnology ◽

10.1007/s12010-020-03240-x ◽

2020 ◽

Vol 191 (1) ◽

pp. 92-103

Author(s):

Sang-Woo Han ◽

Jong-Shik Shin

Keyword(s):

Computational Modeling ◽

Kinetic Analysis ◽

Kinetic Parameters ◽

Kinetic Resolution ◽

Chiral Amine ◽

Intrinsic Kinetic

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Determination of intrinsic kinetic parameters in photocatalytic multi-tube reactors by combining the NTUm-method with radiation field modelling

Chemical Engineering Journal ◽

10.1016/j.cej.2018.08.010 ◽

2018 ◽

Vol 354 ◽

pp. 1042-1049 ◽

Cited By ~ 4

Author(s):

Jeroen van Walsem ◽

Jelle Roegiers ◽

Bart Modde ◽

Silvia Lenaerts ◽

Siegfried Denys

Keyword(s):

Kinetic Parameters ◽

Radiation Field ◽

Field Modelling ◽

Intrinsic Kinetic

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Determination of the intrinsic kinetic parameters of ammonia-oxidizing and nitrite-oxidizing bacteria in granular and flocculent sludge

Separation and Purification Technology ◽

10.1016/j.seppur.2018.12.048 ◽

2019 ◽

Vol 213 ◽

pp. 571-577 ◽

Cited By ~ 9

Author(s):

Angeles Val del Rio ◽

Jose L. Campos ◽

Cristopher Da Silva ◽

Alba Pedrouso ◽

Anuska Mosquera-Corral

Keyword(s):

Kinetic Parameters ◽

Nitrite Oxidizing Bacteria ◽

Intrinsic Kinetic

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Determination of immobilized enzyme apparent kinetic parameters in packed-bed reactors: Presentation of a new methodology

Food and Bioproducts Processing ◽

10.1016/j.fbp.2008.02.002 ◽

2008 ◽

Vol 86 (2) ◽

pp. 104-108 ◽

Cited By ~ 5

Author(s):

A.R. Özdural ◽

A. Alkan-Sungur ◽

I.H. Boyaci ◽

C. Webb

Keyword(s):

Kinetic Parameters ◽

Immobilized Enzyme ◽

Packed Bed ◽

Packed Bed Reactors ◽

Apparent Kinetic Parameters

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Kinetics of thermal decomposition of aseptic packages

Chemical Papers ◽

10.2478/s11696-013-0319-7 ◽

2013 ◽

Vol 67 (12) ◽

Cited By ~ 4

Author(s):

Juma Haydary ◽

Dalibor Susa

Keyword(s):

Thermal Decomposition ◽

Kinetic Parameters ◽

Flow Reactor ◽

Independent Set ◽

Kinetics Of Thermal Decomposition ◽

Thermogravimetric Data ◽

Type Flow ◽

Apparent Kinetic Parameters ◽

Kinetics Of

AbstractKinetics of thermal decomposition of aseptic packages (e.g. Tetrapak cartons) and pyrolysis of this waste in a laboratory flow reactor was studied. Three different models for the calculation of the reaction rate and the determination of apparent kinetic parameters of thermal decomposition were used. The first method assumes a two stage thermal decomposition and the kinetic parameters were determined by fitting a derivative thermogravimetric (DTG) curve to experimentally determined thermogravimetric data of whole aseptic cartons. The second method uses kinetic parameters determined by fitting DTG curves to thermogravimetric data of individual components of aseptic packages. The last method was a multi-curve isoconversion method assuming a change of kinetic parameters with the increasing conversion. All types of the determined kinetic parameters were used in a mathematical model for thermal decomposition of mini briquettes made from aseptic packages at the temperature of 650°C. The model calculated also the heat conduction in the particles and it was verified by an independent set of experiments conducted in a laboratory screw type flow reactor.

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Rod outer segment structure influences the apparent kinetic parameters of cyclic GMP phosphodiesterase.

The Journal of General Physiology ◽

10.1085/jgp.103.6.1071 ◽

1994 ◽

Vol 103 (6) ◽

pp. 1071-1098 ◽

Cited By ~ 82

Author(s):

C L Dumke ◽

V Y Arshavsky ◽

P D Calvert ◽

M D Bownds ◽

E N Pugh

Keyword(s):

Kinetic Parameters ◽

Cyclic Gmp ◽

Structural Integrity ◽

Accurate Estimate ◽

Rod Outer Segments ◽

Turnover Number ◽

Retinal Rod ◽

Apparent Kinetic Parameters ◽

Intrinsic Kinetic ◽

Retinal Rod Outer Segments

Cyclic GMP hydrolysis by the phosphodiesterase (PDE) of retinal rod outer segments (ROS) is a key amplification step in phototransduction. Definitive estimates of the turnover number, kcat, and of the Km are crucial to quantifying the amplification contributed by the PDE. Published estimates for these kinetic parameters vary widely; moreover, light-dependent changes in the Km of PDE have been reported. The experiments and analyses reported here account for most observed variations in apparent Km, and they lead to definitive estimates of the intrinsic kinetic parameters in amphibian rods. We first obtained a new and highly accurate estimate of the ratio of holo-PDE to rhodopsin in the amphibian ROS, 1:270. We then estimated the apparent kinetic parameters of light-activated PDE of suspensions of disrupted frog ROS whose structural integrity was systematically varied. In the most severely disrupted ROS preparation, we found Km = 95 microM and kcat = 4,400 cGMP.s-1. In suspensions of disc-stack fragments of greater integrity, the apparent Km increased to approximately 600 microM, though kcat remained unchanged. In contrast, the Km for cAMP was not shifted in the disc stack preparations. A theoretical analysis shows that the elevated apparent Km of suspensions of disc stacks can be explained as a consequence of diffusion with hydrolysis in the disc stack, which causes active PDEs nearer the center of the stack to be exposed to a lower concentration of cyclic GMP than PDEs at the disc stack rim. The analysis predicts our observation that the apparent Km for cGMP is elevated with no accompanying decrease in kcat. The analysis also predicts the lack of a Km shift for cAMP and the previously reported light dependence of the apparent Km for cGMP. We conclude that the intrinsic kinetic parameters of the PDE do not vary with light or structural integrity, and are those of the most severely disrupted disc stacks.

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