Feeding strategies for tuning poly (3-hydroxybutyrate-co-4-hydroxybutyrate) monomeric composition and productivity using Burkholderia sacchari.
Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P(3HB-4HB)) co-polymers were produced at bench-scale in fed-batch cultivations by Burkholderia sacchari from glucose (main carbon-source) and gamma-butyrolactone (GBL) as co-substrate. As P(3HB-4HB) properties highly depend on the 4-hydroxybutyrate (4HB) molar fraction, it is advantageous to have a thorough knowledge of the process in order to promote the production of the targeted final product. In this work, polymers with a 4HB molar percentage ranging from 1.5 to 8.4% (mol/mol) were obtained as consequence of a fine tuning of the fed-batch operation conditions, namely regarding the co-substrate feeding rate and its addition time, as GBL is toxic to B. sacchari cells. The best results regarding both the 4HB incorporation (molar%) and the co-polymer productivity (7.1% and 1.1g/(L.h) respectively) were reached when a pulse of GBL (<10g/L) was added early in the accumulation phase followed by a constant GBL addition at a rate similar to that of consumption so that a steady co-substrate concentration in the medium was maintained.
['Raposo|Rodrigo S|RS|', 'de Almeida|M Catarina M D|MCMD|', 'da Fonseca|M M R|MMR|', 'Cesário|M Teresa|MT|']
D061249:Batch Cell Culture Techniques D019117:Burkholderia D002087:Butyrates D005947:Glucose D011108:Polymers
Poly (3-hydroxybutyrate-co-4-hydroxybutyrate) Burkholderia sacchari P(3HB-4HB) Gamma-butyrolactone Bioreactor feeding strategy