slide1 l.
Skip this Video
Loading SlideShow in 5 Seconds..
CHAPTER 30 Industrial Microbiology PowerPoint Presentation
Download Presentation
CHAPTER 30 Industrial Microbiology

Loading in 2 Seconds...

play fullscreen
1 / 67

CHAPTER 30 Industrial Microbiology - PowerPoint PPT Presentation

  • Uploaded on

CHAPTER 30 Industrial Microbiology. Industrial Microorganisms and Product Formation Industrial Microorganisms and Their Products. The actual reactions carried out by microorganisms in industrial microbiology are called biocatalysis ( Figure 30.1 ).

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

CHAPTER 30 Industrial Microbiology

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Industrial Microbiology


The actual reactions carried out by microorganisms in industrial microbiology are called biocatalysis (Figure 30.1).

Industrial microbiology uses microorganisms, typically grown on a large scale, to produce valuable commercial products or to carry out important chemical transformations.


An industrial microorganism must produce the product of interest in high yield; grow rapidly on inexpensive culture media available in bulk quantities; be amenable to genetic manipulation; and, if possible, be nonpathogenic. There are many industrial products, including both cells and substances made by cells.

  • Commodity chemicals are inexpensive chemicals produced in bulk, including ethanol, citric acid, and many others.
primary and secondary metabolites

Primary and Secondary Metabolites

Primary metabolites are produced during active cell growth, and secondary metabolites are produced near the onset of stationary phase (Figure 30.2).


Figure 30.3 shows the interrelationship of the main primary metabolic pathway for aromatic amino acid synthesis

  • and the secondary metabolic
  • pathways for a variety of
  • antibiotics.
characteristics of large scale fermentations

Characteristics of Large-Scale Fermentations

Large-scale industrial fermentation presents several engineering problems. Aerobic processes require mechanisms for stirring and aeration.

The microbial process must be continuously monitored to ensure satisfactory yields of the desired product.

Industrial fermentors can be divided into two major classes, those for anaerobic processes and those for aerobic processes (Figure 30.4).

fermentation scale up

Fermentation Scale-Up

Fermentation scale-up is the process of gradually converting a useful industrial fermentation from laboratory scale to production scale. Aeration is a particularly critical aspect to monitor during scale-up studies.

major industrial products for the health industry antibiotics isolation and characterization

Major Industrial Products for the Health Industry Antibiotics: Isolation and Characterization


The industrial production of antibiotics begins with screening for antibiotic producers (Figure 30.7).

Once new producers are identified, purification (Figure 30.8) and chemical analyses of the antimicrobial agent are performed.

If the new antibiotic is biologically active in vivo, the industrial microbiologist may genetically modify the producing strain to increase yields to levels acceptable for commercial development.


Major antibiotics of clinical significance include the -lactam antibiotics penicillin (Figure 30.9) and cephalosporin and the tetracyclines (Figure 30.11).


Cephalosporins are valued clinically not only because of their low toxicity but also because they are broad-spectrum antibiotics, useful against a wide variety of bacterial pathogens.


Figure 30.10 shows the kinetics of the penicillin fermentation with Penicillium chrysogenum.


If the penicillin fermentation is carried out without addition of side-chain precursors, the natural penicillins are produced. The fermentation can be more directed by adding to the broth a side-chain precursor so that only one desired penicillin is produced.


The product formed under these conditions is referred to as a biosynthetic penicillin. To produce the most useful penicillins, those with activity against gram-negative Bacteria, a combined fermentation and chemical approach is used that leads to the production of semisynthetic penicillins.

  • All of these antibiotics are typical secondary metabolites, and their industrial production is well worked out despite the fact that the biochemistry and genetics of their biosynthesis are only partially understood.
vitamins and amino acids

Vitamins and Amino Acids

Vitamins produced microbially include vitamin B12 and riboflavin (Figure 30.12).

The most important amino acids produced commercially are glutamic acid, aspartic acid, phenylalanine, and lysine (Figure 30.13).

Aspartic acid and phenylalanine are the ingredients of the artificial sweetener aspartame, a non-nutritive sweetener of diet soft drinks and other foods sold as low-calorie or sugar-free products.


High yields of amino acids are obtained by modifying regulatory signals that control synthesis of the particular amino acid such that overproduction occurs.

steroids and the biotransformation process

Steroids and the Biotransformation Process

Microbial biotransformation employs microorganisms to biocatalyze a specific step or steps in an otherwise strictly chemical synthesis (Figure 30.14).

enzymes as industrial products

Enzymes as Industrial Products

Microorganisms are ideal for the large-scale production of enzymes. Many enzymes are used in the laundry industry to remove stains from clothing, and thermostable and alkalistable enzymes have many advantages in these markets.


These extracellular enzymes, called exoenzymes, can digest insoluble polymers such as cellulose, protein, and starch. The products of digestion are then transported into the cell where they are used as nutrients for growth.

Certain enzymes are produced in large amounts by some organisms, and instead of being held within the cell, they are excreted into the medium.


The term extremozyme has been coined to describe enzymes that function at some environmental extreme, such as high temperatures or low pH (Figure 30.15). Enzymes from extremophiles are desirable for biocatalyses under extreme conditions.


For some biocatalytic processes, it is desirable to fix soluble enzymes onto a solid surface. These are called immobilized enzymes (Figure 30.16).

major industrial products for the food and beverage industries alcohol and alcoholic beverages

Major Industrial Products for the Food and Beverage IndustriesAlcohol and Alcoholic Beverages


Alcoholic beverages are produced by yeast from the fermentation of sugar to ethyl alcohol and CO2.Wine is produced from grape juice (Figure 30.18), beer from fermentation of malted grain (brewing), and distilled beverages from the distillation of fermented solutions.

vinegar production

Vinegar Production

The active ingredient in vinegar is acetic acid, which is produced by acetic acid bacteria oxidizing an alcohol-containing fruit juice (Figure 30.22).

adequate aeration is the most important consideration in ensuring a successful vinegar process
Adequate aeration is the most important consideration in ensuring a successful vinegar process.
citric acid and other organic compounds

Citric Acid and Other Organic Compounds

A number of organic chemicals are produced commercially by use of microorganisms, of which the most important economically is citric acid, produced by Aspergillus niger (Figure 30.24).

yeast as a food and food supplement

Yeast as a Food and Food Supplement

Yeast cells are grown for use in the baking and food industries (Table 30.5).

Commercial yeast is produced in large-scale aerated fermentors using molasses as the main carbon and energy source (Figure 30.25).
mushrooms as a food source

Mushrooms as a Food Source

The most important food produced from a microorganism is the mushroom, which is produced not for its protein but for its flavor.