A Model Predicting the Effects of Oscillating Dissolved Oxygen Tension on the Molecular Weight of Alginate by Azotobacter Vinelandii
نویسندگان
چکیده
A semiempirical model that describes and predicts the evolution of alginate mean molecular weight (MMW) produced by Azotobacter vinelandii, from cultures carried out under oscillating dissolved oxygen tension (DOT), was developed. Data from the literature of cultures carried out at constant DOT was used. The model is able to explain that the main effect on the MMW of alginate is linked with the amplitude of the DOT sinusoidal wave. The model also predicts the weak effect of the oscillating DOT over kinetics of biomass growth, alginate production and sucrose consumption, as compared with cultures conducted at constant DOT.
منابع مشابه
Molecular and bioengineering strategies to improve alginate and polydydroxyalkanoate production by Azotobacter vinelandii
Several aspects of alginate and PHB synthesis in Azotobacter vinelandii at a molecular level have been elucidated in articles published during the last ten years. It is now clear that alginate and PHB synthesis are under a very complex genetic control. Genetic modification of A. vinelandii has produced a number of very interesting mutants which have particular traits for alginate production. On...
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