Tannase (tannin acyl hydrolase, E.C.3.1.1.20) is an important hydrolysable enzyme with innumerable applications and industrial potential. In the present study, a kinetic model has been developed for the batch fermentation used for the production of tannase by A.flavus MTCC 3783. Maximum tannase activity of 143.30 U/ml was obtained at 96 hours under optimum operating conditions at 35oC, an initi...

Many facultatively fermentative yeast species exhibit a "Kluyver effect": even under oxygen-limited growth conditions, certain disaccharides that support aerobic, respiratory growth are not fermented, even though the component monosaccharides are good fermentation substrates. This article investigates the applicability of this phenomenon for high-cell-density cultivation of yeasts. In glucose-g...

BACKGROUND The production of value-added chemicals alongside biofuels from lignocellulosic hydrolysates is critical for developing economically viable biorefineries. Here, the production of propionic acid (PA), a potential building block for C3-based chemicals, from corn stover hydrolysate is investigated using the native PA-producing bacterium Propionibacterium acidipropionici. RESULTS A wid...

In this study, a mathematical model was proposed and the accuracy of this model was assessed to predict the growth of Pseudomonas aeruginosa and rhamnolipid production under nitrogen limiting (sodium nitrate) fed-batch fermentation. All of the parameters used in this model were achieved individually without using any data from the literature. The overall growth kinetic of the strain was evaluat...

Optimal control theory was applied to the process of batch beer fermentation. The performance functional considered was a weighted sum of maximum ethanol production and minimum time. Calculations were based on the model of Engasser et al. modified to include temperature effects. Model parameters were determined from isothermal batch fermentations. The fermentor cooling duty was the single avail...

This report describes the building of a simulator for prediction of the dissolved oxygen concentration, the oxygen transfer rate and the concentration of carbon dioxide in a fermentation process. The steady state models were made using the linguistic equations method. The dynamic models were made using Simulink ® toolbox in the Matlab ® . At the beginning, some basics about fermentation and mic...

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...

A fermentation process for production of super coiled plasmid DNA in E. coli for use as a DNA vaccine was developed. In the process a feed-back control nutrient feeding strategy based on pH and DO was used to regulate the cell growth rate by controlling the interactivity of the nutrient feed rate, pH and DO. The process increased the total yield of plasmid DNA by approximately 4 fold as compare...

Ethanol production from agro-based raw materials normally involves two major steps, fermentation and distillation. These steps are reviewed, mainly in relation to molasses, which is the most common raw material in tropical countries. The specific effect on fermentation efficiency of molasses quality in terms Fermentable Sugars, the ratio of fermentable to non-fermentable solids, Volatile Acids,...