In 1859, the pioneering French microbiologist Émile Duclaux began his academic career at the École Normale Supérieure in Paris. In 1862, he became an agrégé in physical sciences and took up a position as Pasteur's laboratory assistant. In 1865, having completed his studies, he left Paris for posts at Tours and subsequently at the Faculty of Sciences at Clermont-Ferrand, where he renewed his collaboration with Pasteur. To help revive the local brewing industry, he also undertook experiments on fermentation, first in a makeshift laboratory of his own design and later at the Kuhn brewery in nearby Chamalières. He returned to Paris in 1878, working as professor at the Institut Agronomique and as lecturer in biological chemistry at the Sorbonne, where he gave the world's first course in microbiology.

Duclaux's specialities included osmosis, molecular adhesion, surface tension, fermentation processes and the involvement of microbes with fermentation processes. He also studied digestive enzymes, including those that required the presence of microbes to function properly.

He was a legendary teacher. Recalling his days as a medical student at Clermont-Ferrand, Émile Roux painted a vivid portrait of Duclaux as teacher: "Duclaux presented a subject so clearly that everyone understood. His words were those of a scientist burning with the 'sacred fire.' He set [one's] thinking, to the point that when one had finished his course, he seemed to be there still." (Qtd in Delaunay, p. 212)


Delaunay, Albert. "Duclaux, Émile." Complete Dictionary of Scientific Biography. New York: Charles Scribner's Sons, 2008, IV, 210-121.

Created 15 February 2017

Last modified 8 February 2023