Albert Szent-Györgyi

From the Nobel Foundation:

Szent-Györgyi's early researches at Groningen concerned the chemistry of cell respiration. He described the interdependence of oxygen and hydrogen activation and made his first observations on co-dehydrases and the polyphenol oxidase systems of plants. He also demonstrated the existence of a reducing substance in plant and animal tissues. At Cambridge and during his early spell in the United States, he isolated from adrenals this reducing substance, which is now known as ascorbic acid. Returning to Cambridge in 1929, he later described the pharmacological activity of the nucleotides with Drury.

On his return to Hungary, he noted the anti-scorbutic activity of ascorbic acid and discovered that paprika (Capsicum annuum) was a rich source of vitamin C. His persistent studies of biological oxidation led to the recognition of the catalytic function of the C₄-dicarboxylic acids, the discovery of "cytoflav" (flavin) and a recognition of the biological activity and probable vitamin nature of flavanone (vitamin P).

"Albert Szent-Györgyi: Biographical," Nobel Foundation (1937)

Nobel Laureate, Prize in Physiology or Medicine, 1937