Microbes in Industrial Products

• Microbes are used to synthesise many products valuable to human beings, including beverages, organic acids, vitamins, growth hormones, enzymes, antibiotics, and other useful compounds.
• These products are secondary metabolites produced during the idiophase and are not required for microbial growth.
• The substrate type and the microorganism type determine the secondary metabolite produced.

• Industrial-scale production requires growing microbes in very large vessels called fermenters or fermentors.
• The main function of a fermenter is to provide a controlled environment for the growth of a microorganism or a defined mixture of microorganisms to obtain the desired product.
• A fermentor is described as a closed vessel with arrangements for aeration, agitation, temperature control, pH control, and removal of waste biomass along with products.

Zymology is the applied science that deals with the biochemical processes of fermentation and their practical uses.

Oenology is the science and study of wine and winemaking.

Alcoholic Beverages

• Alcoholic beverages are products of alcoholic fermentation of specific substrates.
• Microbes, especially yeasts, have been used since ancient times to produce wine, beer, whisky, brandy, and rum.
• Saccharomyces cerevisiae, commonly called brewer’s yeast, is used for fermenting malted cereals and fruit juices to produce ethanol.
• Saccharomyces cerevisiae var. ellipsoideus is also mentioned as brewer’s yeast for the production of alcohol from malted cereals and fruit juices.

Distilled and Non-distilled Beverages:

Additional Beverage Details:

• Beer may be produced by Saccharomyces carlsbergensis or Saccharomyces cerevisiae.
• Wine is produced by fermenting grape juice with yeast.
• Red wine is made from black grapes, including the skins and sometimes the stems, while white wine is made only from the juice, without skins or stems.
• Rum is made from fermented sugarcane, molasses, or sugarcane juice by Saccharomyces cerevisiae.
• Whiskey is a distilled alcoholic beverage made from fermented grain mash by Saccharomyces cerevisiae.

Traditional Fermented Drinks:

• A traditional drink prepared by fermenting sugar sap from palm plants, including the coconut palm, is described.
• Pathaneer is obtained from fermenting the sap of palms and coconut trees.
• When pathaneer is left undisturbed for a few hours, it ferments with the help of naturally occurring yeast, forming toddy.
• Toddy contains about 4% alcohol.
• After 24 hours, toddy becomes unpalatable and is used to produce vinegar.
• Fenny is made by fermenting the fleshy pedicels of cashew fruits.

Alcohol Content:

• Beer contains 3-5 % alcohol.
• Wine contains 9-14 % alcohol.
• Wine coolers contain about 4-6% alcohol.
• Distilled spirits such as whiskey, gin, scotch, and vodka usually contain 35-50 % alcohol.

Ethanol:

• Saccharomyces cerevisiae is the major producer of ethanol.
• Ethanol is used for industrial, laboratory, fuel, and beverage purposes.
• Ethanol is also referred to as industrial alcohol.
• Bacteria such as Zymomonas mobilis and Sarcina ventriculi are also involved in ethanol production.
• Principal substrates for commercial ethanol production include molasses, corn, potatoes, and wood wastes.

Production of Organic Acids

• Microbes are used for the commercial and industrial production of certain organic acids.
• These compounds may be produced directly from glucose or formed as end products from pyruvate or ethanol.
• Certain microbes convert carbohydrates into organic acids.

Organic Acids and Microbes

Uses:

• Citric acid is used in confectionery.
• Fumaric acid is used in resins as a wetting agent.
• Gluconic acid is used in medicine for the solubility of calcium.

Production of Vitamins

• Vitamins are complex organic nitrogenous compounds required in small amounts and capable of performing many life-sustaining functions in the body.
• These compounds are not synthesised in humans except for vitamin D, so they must be supplied in the diet.
• Microbes can synthesise vitamins and are used in commercial production.

Vitamins:

• Thiamine
• Riboflavin
• Pyridoxine
• Folic acid
• Pantothenic acid
• Biotin
• Vitamin B12
• Ascorbic acid
• Beta-carotene
• Ergosterol

Vitamins and Microbial Sources:

Antibiotics are chemical substances produced by some microbes that can kill or retard the growth of other disease-causing microbes.

• Antibiotics are regarded as one of the most significant discoveries of the twentieth century.
• Most antibiotics are secondary metabolites.
• "Antibiotic" means “against life."
• Antibiosis is the property of antibiotics to kill microorganisms.

Importance:

Antibiotics have greatly improved the ability to treat deadly diseases such as plague, whooping cough, diphtheria, leprosy, meningitis, syphilis, and tuberculosis.

Discovery of Penicillin:

• Penicillin was the first antibiotic discovered.
• Alexander Fleming observed a mould growing in an unwashed culture plate of staphylococci around which the bacteria could not grow.
• The mould was identified as Penicillium notatum.
• The chemical produced by the mould was named penicillin.
• Its full potential as an effective antibiotic was established later by Ernst Chain and Howard Florey.
• Penicillin was extensively used to treat wounded soldiers during World War II.
• Fleming, Chain, and Florey were awarded the Nobel Prize in 1945.
• Penicillin is produced by Penicillium notatum and Penicillium chrysogenum.
• Penicillin inhibits synthesis of the bacterial cell wall.

Broad-spectrum and Narrow-spectrum Antibiotics

• Broad-spectrum antibiotics act against a wide range of disease-causing bacteria.
• Narrow-spectrum antibiotics are active against a specific group of bacteria.
• Narrow-spectrum antibiotics are preferred because they target specific pathogenic organisms and are less likely to cause resistance.

Antibiotic Resistance

• Antibiotic resistance occurs when bacteria develop the ability to defeat the drug designed to kill or inhibit their growth.
• It is accelerated by the misuse and overuse of antibiotics and poor infection prevention and control.
• “Superbug” refers to strains of bacteria resistant to most antibiotics commonly used today.

Antibiotics and Microbial Sources

Note:

• Streptomycin was first isolated by Waksman and associates in 1944 from Streptomyces griseus.
• Erythromycin was derived by Selman Waksman in 1952 from Streptomyces erythreus.
• Selman Waksman discovered streptomycin and first used the term "antibiotic" in 1943.

• Enzymes are proteins known as biocatalysts.
• They promote reactions more quickly and efficiently.
• In living beings, enzymes play a key role in metabolic reactions and are essential for survival.
• Many microbes synthesise and excrete large quantities of enzymes into the surrounding medium.
• This property makes microbes useful for commercial enzyme production.

Enzymes:

• Amylase
• Cellulase
• Protease
• Lipase
• Pectinase
• Streptokinase
• Invertase
• Glucose isomerase
• Glucose oxidase
• Rennin

Enzymes and Microbial Sources:

Uses of Enzymes

• Enzymes improve the quality of fabrics in the textile industry.
• They are used in biomechanical pulping and bleaching in the pulp and paper industry.
• They are used in fermentation processes for the production of bread, wine, and beer.
• They are used in the extraction of carotenoids and olive oil.
• Lipases are used in the detergent industry and help remove oily stains from laundry.
• Lipases are also used in cosmetics, animal feed, and agricultural industries.
• Pectinases and proteases are used to clarify bottled fruit juices.
• Cellulase is also mentioned in juice clarification.
• Glucose oxidase is used to remove oxygen from soft drinks and salad dressings.
• Amylases are used as sizing agents in the textile and paper industry, in bread production, in chocolate and corn syrups, and for the removal of spots in laundry.
• Rennet is used to separate milk into solid curds for cheese making.
• Microbial enzymes are also used for synthesis of alkene oxides in plastics production.

Streptokinase

• Streptokinase is produced by Streptococcus.
• It is modified by genetic engineering in one linked treatment.
• It has a fibrinolytic effect.
• It is used as a clot-buster to remove blood clots from blood vessels in patients who have had a myocardial infarction.

Gibberellin Production

• Gibberellins are a group of growth hormones mainly produced by higher plants and fungi.
• It promotes growth by stem elongation.
• The first gibberellin was isolated by Yabuta and Sumiki in 1938 from rice seedlings infected with Gibberella fujikuroi.
• About 15 different types of gibberellins have been isolated.

Uses of Gibberellins

• They are used to induce parthenocarpy in apple and pear.
• They are used in breaking seed dormancy.
• They are used to induce flowering in long-day plants.
• They are used to enlarge grapefruits.

Bioactive Molecules and Medical Uses:

• Microbes are also used for the production of bioactive molecules.
• These molecules have important medical uses.

• Cyclosporin A is also mentioned for anti-inflammatory, antifungal, and anti-parasitic properties in one linked treatment.
• Statins act by competitively inhibiting the enzyme responsible for the synthesis of cholesterol.

• Industrial fermentation uses large, controlled vessels to cultivate microbes for the large-scale production of valuable secondary metabolites.
• Yeast (Saccharomyces cerevisiae) ferments sugars in cereals and fruit juices to produce non-distilled (wine and beer) and distilled (whisky and rum) alcoholic beverages.
• Specific microbes convert carbohydrates into commercial organic acids, such as Aspergillus niger for citric acid and Lactobacillus for lactic acid.
• Microbes are utilized to commercially synthesize essential vitamins, like vitamin B12 and riboflavin, which humans cannot produce naturally.
• Certain microbes produce antibiotics, like penicillin, which are chemical substances that kill or inhibit the growth of disease-causing pathogens.
• Microbial enzymes act as commercial biocatalysts, functioning in detergents (lipases), juice clarification (pectinases), and medicine (streptokinase).
• Microbes produce critical bioactive molecules for medicine, including immunosuppressive agents (Cyclosporin A) and cholesterol-lowering drugs (statins).
• Fungi (Gibberella fujikuroi) synthesize gibberellins, which are agricultural hormones used to promote plant stem elongation and break seed dormancy.