Study the Relation between Fermentation Characteristics of Submerged Fluid and Improving the Lactic Acid Production by Fungi

Lactic acid (LA) is a colorless, odorless monocarboxylic acid naturally produced by many organisms. This weak acid has extensively used as an excipient in the food, cosmetics, pharmaceutical and chemical industries. The L-isomer is being preferred for food and pharmaceutical applications. Lactic acid can be produced by several microorganisms classified into bacteria, fungi, yeast, cyanobacteria, and algae. Among these microorganisms, lactic acid production using fungal fermentation showed high efficiency. Widely used method for the production of lactic acid is batch fermentation. Hydrodynamic conditions in the fermenter influence the morphology of the fungus and thus the rheology. 

High agitation rates, which are required for optimum mass transfer, lead to high shear stress. Consequently, mycelial networks are fragmented, increasing the amount of free filaments and hence the viscosity. Besides, high viscosity at low agitation rate causes insufficient mass transfer and oxygen limitation. Because of an existing dynamic relationship between fermentation conditions and fungal growth patterns, an improved impeller that was sufficiently flexible for submerged cultures would be an advantage in the design of an efficient enzyme production system.

Integrating cellulose by recombinant molecular biology techniques

At a time when the demand for the demand renewable is growing at the rate of 30 billion gallons of biofuels by the end of 2020, it is time to explore new technologies that are capable of generating cellulosic ethanol. This can be done by breaking down cellulose into cellulase enzyme. However, this cannot be the mostable and degrades at higher temperatures in bioreactors. A study was conducted to create eco-friendly bioethanol from cellulosic waste recombinant that can be used at higher temperature in bioreactors. The project involved molecular cloning of genes for cellulose-degrading enzymes based on bacterial source, expressing the recombinant proteins in E. coli and optimized the enzymatic activity. The study could generate in vitro bacterial expression systems to produce recombinant His-tag purified protein which showed cellulase like activity.

Cheap, clean, green energy production is a goal of Department of energy and EPA. Biofuels are made by converting renewable materials- -for example, corn kernels, wood chips left over from pulp and paper production, prairie grasses, and even garbage--into fuels and chemicals. Most biofuels used today are made from the fermentation of starch from corn kernels. That process, although simple, is costly because of the high price of the corn kernels themselves.