title: Pulse respirometry in two-phase partitioning bioreactors: case study of terephthalic acid biodegradation.
abstract: Two-phase partitioning bioreactors (TPPBs) are based on the addition of an organic phase, often called vector, to a bioreactor in order to increase mass transfer of oxygen or gaseous substrates from the gaseous phase to the aqueous phase. In TPPBs, like in any other reactor design, the characterization of the bioprocess is often required for design, control, and operation purposes. Pulse respirometry is a method that allows for microbial processes characterization through the determination of several stoichiometric and kinetic parameters with relatively little experimental effort. Despite its interest and its previous application in countless applications, pulse respirometry has never been applied in TPPBs. In this work, pulse respirometry was assessed in a model TPPB degrading terephthalic acid and using Elvax™ as solid vector to enhance oxygen transfer. The results indicated that the addition of 10 to 20% Elvax increased oxygen transfer by up to 97%, compared to control with no vector. Pulse respirometry was successfully applied and allowed for the determination of the growth yield, the substrate affinity constant, and the maximum growth rate, within other. It is concluded that pulse respirometry is a useful method, not only for the characterization of processes in TPPBs but also for the selection of a vector within several brands commercially available.
authors.affiliation: Laboratorio de Bioingeniería, Departamento de Bioingeniería, Unidad Profesional Interdisciplinaria de Biotecnología del Instituto Politécnico Nacional, México, DF, México. iqbeto@yahoo.com.mx
authors.forename: Alberto
authors.initials: A
authors.lastname: Ordaz
authors.forename: Guillermo
authors.initials: G
authors.lastname: Quijano
authors.forename: Frederic
authors.initials: F
authors.lastname: Thalasso
authors.forename: Claudio
authors.initials: C
authors.lastname: Garibay-Orijel
mesh_terms: D001673:Biodegradation, Environmental; D019149:Bioreactors; D010795:Phthalic Acids / Q000378:metabolism*
chemical_list: D010795:Phthalic Acids; C011363:terephthalic acid