March 2016

Unseen World

Few individuals have had the fundamental impact on the course of Public Health as renowned microbiologist and chemist Louis Pasteur (1822 – 1895). Not only did his insightful research forever debunk the notion of spontaneous generation – paving the way for the acceptance of germ theory and our understanding of the role of microorganisms in pathogenesis – Pasteur was among the first to consider the vast potential of rearing beneficial microorganisms.

His foundational work in the 1850s would lay the groundwork for industrial-scale manufacturing of countless important fermentation products more than 100 years later.

Fermentation is the process by which chemical properties of a substance are broken down by microorganisms. By controlling the process, scientists and manufacturers are able to grow vast quantities of microorganisms with useful properties.

Food Products – Fermentation helps to preserve foods, many of which have health benefits stemming from beneficial bacteria (probiotics). Popular fermented food products include yogurt, cheeses, sauerkraut, beer, and wine.

Biofuel – Bioethanol is generated from the fermentation of corn sugars and sugars from other forms of biomass such as trees and grasses.

Crop Protection and Forestry – Bioinsecticides and biofungicides, derived from microorganisms with highly specific activity against a wide range of pests, are used in integrated pest management programs across the globe.

Pharmaceuticals – Fermentation of both prokaryotic (bacteria) and eukaryotic (fungi, yeasts) microorganisms figure prominently in the development and manufacture of several important medicines including antibiotics.

Public Health – Fermentation products have forever changed the public health landscape. Biological larvicides such as Bacillus thuringiensis subsp. israelensis (see April) have become the basis of integrated vector management programs around the world. In the 1970s – 80s, Merck developed Ivermectin through fermentation, a preventative drug that now protects millions of Africans from the parasitic worm that vectors Onchocerciasis (February).

After making the decision to continue developing ivermectin for humans – despite the certainty that the company would never earn profit from the drug – Merck chairman Dr. P. Roy Vagelos announced in October 1987 that Merck would provide the drug to third world countries free of charge.