Process Development Acetobacter

Research on development of the acetic acid production process involves many types of bioreactors. In O Table 1.5, the characteristics of some of these experimental bioreactors and 

Comparison of bioreactors for oxidation of ethanol to acetic acid by Acetobacter 

Bioreactor and process Acetic acid output (g/1) Acetic acid productivity (g/i-h) Stabie operation (days) References 

Cell recycle continuous, fed batch, hollow fiber filtration 90 2.67 14 Parketal. (1991) 

Organic Acid and Solvent Production Acetic, Lactic, Gluconic, Succinic, and Polyhydroxyalkanoic Acids 

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Whole-cell based biocatalysis utilizes an entire microorganism for the production of the desired product. One of the oldest examples for industrial applications of whole-cell biocatalysis is the production of acetic acid from ethanol with an immobilized Acetobacter strain, which was developed nearly 200 yr ago. The key advantage of whole-cell biocatalysis is the ability to use cheap and abundant raw materials and catalyze multistep reactions. Recent advances in metabolic engineering have brought a renaissance to whole-cell biocatalysis. In the following sections, two novel industrial processes that utilize whole-cell biocatalysis are discussed with emphasis on the important role played by metabolic engineering. 

Helpful Food Bacteria. Fortunately, many bacteria benefit foods and are widely used in biological oxidation reactions and in fermentation processes. Butter and cheese, for example, depend on bacteria for the development of their characteristic flavors. Bacteria are indispensable for making pickles, sauerkraut, olives, yogurt, buttermilk, beer, and wine. They are also employed in the manufacture of corn beef and rye bread. Bacteria are used to enhance the flavor of coffee, being introduced just prior to the roast. Also, a bacterium of the genus Acetobacter is used in making vinegar. 

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