The Breakthroughs of Karl Folkers in Biochemistry and Human Nutrition

Professor Karl August Folkers (Figure 1), a biochemist from the United States, was the head of one of the two research groups, one in England and one in the United States. In 1948, the two groups independently and simultaneously reported the isolation of vitamin B12 [1,2]. Most of Folkers’ work was carried out while working at the Merck Company (later Merck Sharp & Dohme) from 1934 to 1963. His laboratory at Merck was known for isolation, purification, synthesis, and structural determination of many bioactive natural products [3,4], including isolation and determination of the biological structure of various Erythrina alkaloids [4]. They also were the first to describe the synthesis [5,6] and structure [7] of vitamin B6 (pyridoxine, pyridoxal, and pyridoxamine), and the synthesis of pantothenic acid [8], biotin [9], lipoic acid [10], and mevalonic acid [11].