The commercial microbial products

Industrial fermentation is the intentional use of fermentation by microorganisms such as bacteria and fungi to make products useful to humans.

Vitamins are sold in large quantities combined in tablet form and are used as individual food supplements. Microbes can provide an inexpensive source of some vitamins. Vitamin B I is produced by Pseudomonas and Propionibacterium species. Riboflavin (B 2 ) is another vitamin produced by fermentation, mostly by fungi such as Ashbya gossypii. Vitamin C (ascorbic acid) is produced at the rate of 20,000 tons per year by a complicated modification of glucose by Acetobacter species.

Modern pharmaceutical microbiology developed after World War II, when production of antibiotics was introduced. All antibiotics were originally the products of microbial metabolism. Many are still produced by microbial fermentations, and work continues on the selection of more productive mutants by nutritional and genetic manipulations. At least 6000 antibiotics have been described. One organism, Streptomyces hygroscopius, has different strains that make almost 200 different antibiotics. Antibiotics are typically made industrially by inoculating a solution of growth medium with spores of the appropriate mold or streptomycete and vigorously aerating it.

VII Remember the following word and word-combinations:

Quantity, combined in tablet form, food supplements, inexpensive source, rate, to introduce, appropriate, vigorously aerating.

VIII Give Russian equivalents:

Генетические манипуляции, промышленная ферментация, пищевые добавки, полезные для людей, аскорбиновая кислота.

IX Answer the questions:

1. What are industrial fermentations?

2. What kind commercial microbial product do you know?

3. What vitamin is produced by Pseudomonas and Propionibacterium species?

4. What vitamin is produced by Ashbya gossypii?

5. What vitamin is produced by Acetobacter species?

X Retell the text.

45 Practical lesson

Rules of reading: Theletter combinations kn:

Word formation: suffix of adjective – able

Text:Biotechnology and future

Assignments to do:

I Remember:

a) The rules of reading the letter combinations kn is pronounced as [n]: to know

b) Suffix – able form the adjectives from the verbs: to renew – renewable

II Read the words paying attention to their pronunciation:

Knife, knack, knowledge, knap, knee.

III Form adjective from the verb:

To comfort, to increase, to read, to avail, to value.

IV Read and translate the text about biotechnology

Biotechnology and the Future

Microbes have always been exceedingly useful to humankind, even when their existence was unknown. They will remain an essential part of many basic food-processing technologies. The development of recombinant DNA technology has further intensified interest in industrial microbiology by expanding the potential for new products and applications. As the supplies of fossil energy become more scarce, interest in renewable energy sources, such as hydrogen and ethanol, will increase. The use of specialized microbes to produce such products on an industrial scale will probably become more important. As new biotechnology applications and products enter the marketplace, they will affect our lives and well-being in ways that we can only speculate about today.

V Remember the following word and word-combinations:

Exceedingly useful to humankind, existence, food-processing technologies, expanding the potential, supply, fossil, scarce, renewable energy sources, industrial scale, marketplace, well-being, to speculate.

VI Complete the sentences:

1. Microbes have always been exceedingly useful to humankind…

2. They will remain an essential part of many basic…

3. As the supplies of fossil energy become more scarce, interest in renewable energy sources, such as…

4. The use of specialized microbes to produce such products on an industrial scale will probably become…

5. As new biotechnology applications and products enter the marketplace, they will affect our lives and well-being…

VII Find the pairs of synonyms:

Well-being, humankind, health, application, important, use, mankind, significant.