INVESTIGADORES
DIAZ Maria Soledad
congresos y reuniones científicas
Título:
Modeling the fermentation kinetics for poly(β-hydroxybutyrate) production by Bacillus megaterium BBST4
Autor/es:
FERNANDO D. RAMOS; CLAUDIO A. DELPINO; MARCELO A. VILLAR; M. SOLEDAD DIAZ; MOITINHO ALVES TITO
Lugar:
Bahía Blanca
Reunión:
Congreso; IX Congreso Argentino de Ingeniería Química; 2017
Resumen:
Poly(β-hydroxybutyrate) (PHB), which belong to the family of poly(hydroxyalcanoate)s (PHAs), is considered a promising polymer not only because it can be produced from sustainable sources such as glycerol, a co-product in biodiesel production, but also for its mechanical properties [1] and applications as packaging, carriers for drug de-livery and medical uses among others [2].In the last few years there has been a growing interest in the study of modeling biopol-ymer production from fermentation processes. In order to improve yield and productivity of biopolymers and reduce the production cost, several authors have proposed different models for batch and fed batch fermentations [3].Based on the approach presented above, the purpose of this work is to present a model considering the biopolymer production by means of Bacillus megaterium BBST4 isolated from superficial sediments of the Bahía Blanca estuary [4]. We also perform a parameter es-timation in order to adjust the implemented model to the experimental data to obtain reliable bioreaction kinetics. In this context, we look forward to concentrate our future research on developing valuables mathematical tools which could attend the different constraints of bi-opolymer production at higher scales.The mineral salt medium used in the experiments was the one suggested by Faccin et al., 2009 [5]. Glycerol (20 g/L) and urea (2.2 g/L) were the carbon and nitrogen source, re-spectively. The microorganisms were cultivated using an incubator shaker (New Brunswick Scientific, Excella E24) at an agitation rate of 250 rpm and 33 ºC [6] for 29 h in 1000 mL Erlenmeyer flasks with a 500 mL working volume. Several process variables were measured at different time points using analytical methods, namely, total biomass, carbon source, nitro-gen source, pH and biopolymer production.The fermentation process is represented by a differential-algebraic equations system. In order to obtain an appropriate representation, function and parameter estimation is formu-lated as a dynamic optimization problem, with a global approach, using orthogonal colloca-tion over finite elements, in GAMS [7].We propose a mathematical model based on an adaptation of a differential-algebraic equations system. A satisfactory adjustment of the experimental data after parameter estima-tion, resulting in a model that can represent and quantitatively analyze the PHB production kinetics of a Bacillus megaterium BBST4 strain is obtained.