Buchner studied chemistry under Adolf von Baeyer and botany in his native city of Munich, gaining his doctorate in 1888. He was Baeyer's assistant until 1893. In 1897, while associate professor of analytical and pharmaceutical chemistry at Tübingen, he observed fermentation of sugar by cell-free extracts of yeast. Following Pasteur's work (1860), fermentation had been thought to require intact cells, and Buchner's discovery of zymase was the first proof that fermentation was caused by enzymes and did not require the presence of living cells. The name ‘enzyme’ came from the Greek en = in and zyme = yeast. Buchner also synthesized pyrazole (1889). He was professor of chemistry at the University of Berlin from 1898 and won the Nobel Prize for chemistry in 1907 for his work on fermentation. He was killed in Rumania, whilst serving as a major in World War I.