title: Development of a mathematical model for the growth associated Polyhydroxybutyrate fermentation by Azohydromonas australica and its use for the design of fed-batch cultivation strategies.
abstract: In the present investigation, batch cultivation of Azohydromonas australica DSM 1124 was carried out in a bioreactor for growth associated PHB production. The observed batch PHB production kinetics data was then used for the development of a mathematical model which adequately described the substrate limitation and inhibition during the cultivation. The statistical validity test demonstrated that the proposed mathematical model predictions were significant at 99% confidence level. The model was thereafter extrapolated to fed-batch to identify various nutrients feeding regimes during the bioreactor cultivation to improve the PHB accumulation. The distinct capability of the mathematical model to predict highly dynamic fed-batch cultivation strategies was demonstrated by experimental implementation of two fed-batch cultivation strategies. A significantly high PHB concentration of 22.65 g/L & an overall PHB content of 76% was achieved during constant feed rate fed-batch cultivation which is the highest PHB content reported so far using A. australica.
authors.affiliation: Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
authors.forename: Geeta
authors.initials: G
authors.lastname: Gahlawat
authors.forename: Ashok K
authors.initials: AK
authors.lastname: Srivastava
mesh_terms: D042401:Alcaligenaceae / Q000254:growth & development / Q000378:metabolism*; D019149:Bioreactors; D005285:Fermentation; D006885:Hydroxybutyrates / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D008962:Models, Theoretical; D011091:Polyesters / Q000737:chemistry / Q000378:metabolism*
chemical_list: D006885:Hydroxybutyrates; D011091:Polyesters