Robert Koch's Nobel Prize Diploma

Robert Koch was a pioneer in the field of bacteriology, which he established as a branch of microbiology. He was awarded the Nobel Prize for the discovery of the tuberculosis pathogen. Since only living bacteria can be studied, they need a nutrient medium. Initially, gelatine was used for this purpose. Fanny Angelina Hesse (1850–1934) had the idea to cultivate bacteria on agar agar. She was the wife of a short-term research assistant of Koch and used the powder obtained from seaweed for gelling. Unlike gelatine, it does not become liquid at higher temperatures. When Koch announced his discovery in 1882, he mentioned agar agar, but not Hesse's name.