Over the last two decades, most of Italian vines have produced grapes with higher sugar to total acid ratios, greater concentrations of phenols and aromatic compounds and greater potential wine quality. As a consequence, the musts obtained by these grapes are more difficult to process because of the risk of slowing or stuck of fermentation. With the aim of describing the time evolution of the s...

The fermentation kinetics of penicillin production by Penicillium chrysogenum was carried out at 27°C and pH 6.0. Batch and repeated batch fermentations using agar-immobilized cells in fluidized bed bioreactor were studied for their potential application in production of penicillin from lactose, a fermentable sugar. Kinetics of immobilized cell fermentation, showed the penicillin yield of ~0.01...

Gellan gum production was carried out by Sphingomonas paucimobilis ATCC 31461 in a simplified medium with a short incubation time, and a kinetic model for understanding, controlling, and optimizing the fermentation process was proposed. The results revealed that glucose was the best carbon source and that the optimal concentration was 30 g liter(-1). As for the fermenting parameters, considerab...

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,...

Background: Aflatoxins are fungal secondary metabolites negatively affecting ruminant performance; however, little information is available on their impact on rumen fermentation. Aims: This study aimed at determining the effects of different concentrations of aflatoxin B1 (AFB1) from Aspergillus flavus on in vitro gas production and ruminal fe...

Rhamnolipids find broad applications as natural surfactants, emulsifiers, and antibiotics because of their low toxicity, high biodegradability and environmental soundness. In this study, a pH stage-controlled process of fermentation of rhamnolipids by Pseudomonas aeruginosa O-2-2 was established. A yield of 24.06 g/L in batch fermentation was achieved in a 5-L fermentor via the optimization of ...

Acetone-butanol-ethanol (ABE) fermentation by clostridia has shown promise for industrial-scale production of biobutanol. However, the continuous ABE fermentation suffers from low product yield, titer, and productivity. Systems analysis of the continuous ABE fermentation will offer insights into its metabolic pathway as well as into optimal fermentation design and operation. For the ABE ferment...

Two experiments were conducted to study the effects of methionine supplementation on ruminal fermentation and digesta kinetics. In Exp. 1, nine ruminally cannulated beef heifers (average initial BW = 527 kg) in a crossover design were fed low-quality grass hay and cottonseed meal with or without 11.4 g of supplemental methionine (polysaccharide-coated). Particulate and fluid kinetics, rate of D...

Currently, the oil crisis and serious environmental problems related to fossil fuels have caused the world to turn more attention toward biofuels production, especially ethanol fermentation from biomass. An appropriate kinetic model of ethanol fermentation would be a powerful instrument for fermentation efficiency increase and process optimization. The well-known Monod equation has been widely ...

We provide optimal feed trajectories for fedbatch fermentation of microorganisms with substrate inhibition kinetics. demonstrate that the are non-unique and analytical procedures solving control problem. Since, this is essential practical operations as a numerical solution could be any feasible solutions. In addition, we investigate sensitivity bang-bang from point view. This insight relevant m...