Making Penicillin, Part I: Isolation

Introduction

Sir Alexander Fleming first isolated the species of fungus and the anti-bacterial it produced in the 1920's and 30's, but the genus Penicillium and human health have a long history. People would press the moldy side of a slice of bread to a laceration, or throw it into boiling water to make a tea or broth. Live Penicillium fungus can be safely ingested; if you eat unpasteurized camembert or bleu cheese, you’re digesting P. camamberti and P. roqueforti, respectively. However, naturally-produced penicillin (Penicillin G) is unstable in the highly acidic environment of the stomach, and is destroyed before it can be absorbed by the body. Thus, a Penicillium tea is unlikely to have any antibiotic effect. Penicillium G is injected intravenously or intramuscularly to treat syphilis, meningitis, endocarditis, pneumonia and septicemia.¹ As for an open-air wound, you’re probably better served by pouring sugar or honey onto the wound.

Materials

Penicillium chrysogenum culture (optional)
bread/lemon/cantaloupe (optional)
container to hold moisture (optional)

Procedure

References

1. Rossi, S, ed. 2013. Australian Medicines Handbook (2013 ed.). Adelaide: The Australian Medicines Handbook Unit Trust.

2. Laich, F., Fierro, F., and Martin, J. F. 2002. Production of penicillin by fungi growing on food products: identification of complete penicillin gene cluster in Penicillium griseofulvum and a truncated cluster in Penicillium verrucosum. Appl. Environ. Microbiol. 68(3): 1211-1219