Polyhydroxyalkanoates (PHAs) are biological polyesters produced through microbial fermentation processes. They have attracted attention as an alternative source to petro-chemically derived plastics as they are biodegradable, renewable, biocompatible and environmentally friendly. However, a notable limitation for their bulk production is the producer microbes’ low yield and productivity which le...

The two-phase partitioning bioreactor concept appears to have a great potential in enhancing the productivity of many bioprocesses. The proper selection of an organic solvent is the key to successful application of this approach in industrial practice. The integration of fermentation and a primary product separation step has a positive impact on the productivity of many fermentation processes. ...

modeling of fermentation processes is so complicated and uncertain; therefore it is necessary to provide a robust and appropriate dynamic optimization method. in order to obtain the maximum amount of yeast (saccharomyces cerevisiae), the bioreactor must be operated under optimal conditions. to determine substrate feeding in a fed-batch bioreactor, a simulated annealing (sa) approach was examine...

There are three variations of the fermentation process. In batch fermentation, a sterilized nutrient solution in the fermentor is inoculated with micro-organisms and incubation is allowed to proceed. During the course of the fermentation, oxygen is added (as in the case of aerobic microorganisms) and an acid or base to control the pH. The composition of the culture medium, the biomass concentra...

Hemicellulosic biomass from olive-tree pruning (OTPB) was used as a raw material in order to produce hemicellulosic hydrolysate be fermented with the non-traditional yeast Candida guilliermondii FTI 20037 obtain ethanol and xylitol. The main objectives of this research were study most relevant kinetic parameters involved bioconversion process correlation between stirred-tank bioreactor agitated...

In this study, solid-state fermentation of two types of agricultural residues/products for lipase production in a tray-bioreactor was investigated. Rhizopus oryzae was used as a potential fungus strain and two types of agricultural residues including soybean meal and sugarcane bagasse were utilized as substrate. Fermentation was carried out in two different operational conditions: one with cont...

Metabolic engineering has developed microbial cell factories that can convert renewable carbon sources into biofuels. Current molecular biology tools can efficiently alter enzyme levels to redirect carbon fluxes toward biofuel production, but low product yield and titer in large bioreactors prevent the fulfillment of cheap biofuels. There are three major roadblocks preventing economical biofuel...

Quality, quantity, and economy of the fermentation product depend on transient response steady-state process. Due to its simple construction, an industrial batch bioreactor cannot be equipped with a closed-loop control system that applies adding or removing substances during fermentation. This theoretical practical study displays how can controlled, in this case by altering rotational speed sti...