# 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.

- **Patent:** US 2442141
- **Original title:** Method for production of penicillin
- **Owner:** US Department of Agriculture USDA
- **Granted:** 1948
- **Status:** Public domain (expired)
- **Times cited:** 13
- **Field:** biotech, pharmaceutical

## What it does

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 does NOT 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.

## Real-world examples

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

## 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.

## Frequently asked questions

### What does How Andrew Moyer Learned to Mass-Produce Penicillin cover?

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.

### Who owns patent US 2442141?

US Department of Agriculture USDA owns this patent, granted in 1948.

### When does this patent expire?

This patent has expired and is now in the public domain — anyone can use the invention freely.

### What is patent US 2442141 cited by?

This patent has been cited by 13 later patents that build on its ideas.

### What problem does this patent solve?

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.

### What does this patent NOT cover?

Does not cover the discovery of penicillin itself

**Full plain-English explainer:** https://patentbrief.org/patent/us/2442141/vitamin-b12-isolation

**Original patent:** https://patents.google.com/patent/US2442141

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_Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._