Biotechnology, Fermentation, and Drug Discovery Milestones

Posted on Oct 12, 2025 in Biology

Technology and Biotechnology Fundamentals

  • Technology applies scientific knowledge for practical purposes.

Defining Biotechnology

  • An interdisciplinary field utilizing living systems and organisms to develop or make products.

Key Biotechnology Innovations

CRISPR Gene Editing

  • A technology used to precisely manipulate DNA.
  • The 2020 Nobel Prize in Chemistry was awarded to Jennifer Doudna and Emmanuelle Charpentier for their work on CRISPR.

Botox (Botulinum Toxin)

  • Derived from Clostridium botulinum, producing one of the most toxic proteins known.
  • Mechanism: Botox blocks the release of acetylcholine, preventing muscle contraction.
  • Effective dose can be as low as 5 billionths of a gram.

Enzymes in Detergents

  • Enzymes like lipase (often sourced from Candida albicans) are used for fat breakdown and harvested for commercial detergents.

Bioplastics and Sustainability

  • Traditional plastics do not biodegrade easily, leading to micro- and nanoplastics pollution.
  • Bioplastic Solution (PLA): Corn starch is fermented into lactic acid, which is then polymerized into polylactic acid (PLA). PLA biodegrades into CO2 and H2O.
  • Note: PLA requires proper industrial disposal conditions to biodegrade effectively.

Biofuel: Corn-Derived Ethanol

  • Corn starch is converted to sugar using amylase, followed by fermentation to produce ethanol, a renewable fuel source.

Food Science and Fermentation

Understanding High Fructose Corn Syrup (HFCS)

  • HFCS is a cost-effective sweetener.
  • Production Process: Corn is processed into cornstarch, then broken down into oligosaccharides, then glucose (using glucoamylase). Glucose is converted to fructose using glucose isomerase, resulting in a typical blend of 55% fructose and 45% glucose.
  • Nutritionally, HFCS is very similar to sucrose (table sugar), which is 50% fructose and 50% glucose.
  • Both provide 4 calories per gram.

The Process of Fermentation

  • Fermentation relies on microbial enzymes.
  • Example Process: Yeast converts glucose into ethanol and CO2. Lactic acid bacteria can further convert ethanol into acetic acid (vinegar).

Making Apple Cider Vinegar (ACV)

  1. Apple juice is fermented by yeast, producing ethanol.
  2. Bacteria then ferment the ethanol, producing acetic acid (vinegar).

The Role of the Mother of Vinegar

  • A gelatinous mass composed of cellulose, yeast, and acetic acid bacteria.
  • It acts as a starter culture for new vinegar batches.

ACV and Weight Management Research

  • Studies (often random double-blind trials) compare 5–15 mL of apple cider vinegar versus a placebo (e.g., lactic acid).
  • Acetate, a component of vinegar, stimulates GLP-1 and PYY satiety hormones (similar to the mechanism of drugs like Ozempic).
  • Research often compares the effects of polyphenols found in apples versus the acetic acid content in vinegar.

History of Food Fermentation

  • Evidence suggests the first food fermentation occurred approximately 30,000 years ago, often associated with grinding techniques.

Dough Fermentation and Leavening

  • Dough fermentation relies on wild yeast and bacteria.
  • The production of CO2, alcohol, and acids causes leavening, resulting in risen bread (e.g., sourdough, characterized by lactic acid).

Kimchi in Space

  • In 2008, astronaut Yi Soyeon brought specially prepared kimchi into space.

Louis Pasteur’s Contributions

  • Disproved the theory of spontaneous generation through experiments (boiled and sealed broth showed no microbial growth; boiled broth with a broken neck showed growth).
  • Identified Saccharomyces cerevisiae as baker’s yeast.

Sourdough Bread Composition

  • Made using a symbiotic culture of wild yeast and lactic acid bacteria, often exhibiting regional differences in flavor profiles.

Commercial Baker’s Yeast

  • A commercially cultivated strain, such as Fleischmann’s dried yeast.

Traditional Cheese Making

  • Historically, milk was curdled using animal stomach bags.
  • The stomach contains rennet, a complex of enzymes including chymosin, which coagulates milk proteins (casein) to prevent rapid passage through the digestive system.

Chymosin: A Key Protease

  • A protease enzyme that specifically curdles casein proteins in milk.

Pharmaceuticals and Drug Discovery

Penicillin: From Mold to Medicine

  • Ancient Egyptians used moldy bread to prevent infection.
  • Modern discovery: Alexander Fleming observed its effects; Howard Florey and Ernst Chain isolated and purified the compound.

Plant-Derived Drugs: Opium

  • Derived from the opium poppy latex, containing powerful alkaloids like morphine and codeine.

White Willow Bark

  • Source of salicylates, which are precursors to aspirin.

Autumn Crocus

  • Source of colchicine, used historically to treat gout.

Foxglove

  • Source of digitalis and digitoxin, used to treat heart disease and palpitations.

The First Synthetic Drug: Chloral Hydrate

  • Developed by Justus von Liebig, chloral hydrate was used as a sedative. Warning: Can cause overdose.
  • Synthesized from ethanol (derived via fermentation) and chlorine.

The Development of Aspirin

  • Synthesized by Felix Hoffman.
  • The precursor, salicin (from white willow bark), often caused stomach bleeding.
  • Synthesis: Salicin is converted to salicylic acid, which is then reacted with acetic acid to form acetylsalicylic acid (Aspirin).
  • Aspirin is now typically produced synthetically from phenol (a petroleum derivative).

Coumadin (Warfarin) Discovery

  • Discovered in 1933 after cows bled to death from consuming spoiled sweet clover.
  • Sweet clover’s coumarin, when exposed to mold, forms dicoumarol (a potent anticoagulant). Dicoumarol was modified to create Coumadin (Warfarin).
  • Used medically to prevent blood clots, reducing the risk of heart attack and stroke.
  • Historically used as rat poison (Vitamin K is the antidote).

Modern Synthetic Drugs

  • Sildenafil (Viagra): Synthetically produced (often derived from petroleum) and originally developed for angina, now widely used for treating erectile dysfunction.

Biologics Defined

  • Drugs derived from living organisms or their components (e.g., monoclonal antibodies).