Improved production costs will accelerate commercialization of polyhydroxyalkanoate (PHA) polymer and PHA-based products. Plant oils are considered favorable feedstocks, due to their high carbon content and relatively low price compared to sugars and other refined carbon feedstocks. Different PHA production strategies were compared using a recombinant strain of Ralstonia eutropha that produces ...

Improved production costs will accelerate commercialization of polyhydroxyalkanoate (PHA) polymer and PHA-based products. Plant oils are considered favorable feedstocks, due to their high carbon content and relatively low price compared to sugars and other refined carbon feedstocks. Different PHA production strategies were compared using a recombinant strain of Ralstonia eutropha that produces ...

Menaquinone-7 was produced by fermentation mainly using Bacillus subtilis species. Due to the low concentration of menaquinone-7 in fermentation processes and the associated expense of recovering the menaquinone-7, it was desirable to improve the fermentation concentration. The aim of this study was to determine the effect of fed-batch glycerol addition in the production of menaquinone-7 during...

The specific growth rate is one of the most important process variables characterizing the state of microorganisms during fermentations mainly because the biosynthesis of many products of interest is often related with the values assumed by this parameter. In the particular case of the fed-batch operation of Escherichia coli for the production of recombinant proteins, it is important to maintai...

For the first time, a fed-batch fermentation process of Tuber melanosporum was developed for the efficient production of bioactive mycelia and Tuber polysaccharides. Each 1.67 g/L of peptone and 8.33 g/L of yeast extract were added on day 3, 6, and 9, respectively, and sucrose was fed to maintain its concentration around 35-5 g/L when its residual level decreased to 10-5 g/L. Then, the maximal ...

In the paper a genetic algorithm for feed rate profiles synthesis is proposed. An E. coli fed-batch fermentation process is considered. The feed rate profiles based on three different lengths of chromosomes are synthesized. A satisfactory result for the fermentation system due to economical effect and process effectiveness is achieved.

An assessment of a number of different process flowsheets for bioethanol production was performed using dynamic model-based simulations. The evaluation employed diverse operational scenarios such as, fed-batch, continuous and continuous with recycle configurations. Each configuration was evaluated against the following benchmark criteria, yield (kg ethanol/kg dry-biomass), final product concent...

Lactic acid has been shown to have the most promising application in biomaterials as poly(lactic acid). L. rhamnosus ATCC 10863 that produces L-lactic acid was used to perform the fermentation and molasses was used as substrate. A solution containing 27.6 g/L of sucrose (main composition of molasses) and 3.0 g/L of yeast extract was prepared, considering the final volume of 3,571 mL (14.0% (v/v...

A controller based on neuro-dynamic programming coupled with a fuzzy ARTMAP neural network for a fed-batch bioreactor was developed to roduce cloned invertase in Saccharomyces cerevisiae yeast in a fed-batch bioreactor. The objective was to find the optimal glucose feed rate profile eeded to achieve the highest fermentation profit in this reactive system where the enzyme expression is repressed...