How Andrew Moyer Learned to Mass-Produce Penicillin

This 1948 patent details a method for growing the mold Penicillium in large vats using a corn steep liquor medium, which enabled the mass production of life-saving antibiotics.

What it covers

The patent describes a method for increasing the yield of penicillin by using a specific culture medium containing corn steep liquor and lactose. By submerged fermentation in aerated tanks, the mold Penicillium chrysogenum produces significantly higher concentrations of the antibiotic than previous surface-growth methods. This process allowed the transition from slow, small-scale laboratory production to industrial-scale manufacturing.

What it doesn't cover

• —Does not cover the discovery of penicillin itself
• —Does not cover the medical application or dosage of penicillin
• —Does not cover synthetic methods for creating penicillin-like compounds

The clever bit

The innovation was the use of corn steep liquor as a nutrient-rich base for the mold, which acted as a catalyst to drastically boost the production of the antibiotic during fermentation.

Why it matters

This invention was critical for scaling up penicillin production during and after World War II. It transformed a rare, expensive laboratory curiosity into a widely available medicine, effectively launching the modern antibiotic era.

Real-world examples

• 1.Industrial fermentation tanks for pharmaceutical production
• 2.Large-scale antibiotic manufacturing facilities