Anselme Payen (1795-1871), French chemist. Payen was born at Paris and studied at the Ecole Polytechnique under Vauquelin and Chevreul. At the age of 23 he took over the management of a borax refinery. He developed a process from synthesising borax from soda and boric acid that broke the Dutch monopoly on borax importing to Europe and significantly reduced the price. Payen also designed a process for refining sugar and invented a decolorimeter for analysing the product. He was the first to isolate cellulose and the first known enzyme, diastase. He also devised a way to refine starch and alcohol from potatoes. From 1835 he served as professor of chemistry at the Ecole Centrale in Paris, later also at the Conservatoire National des Arts et Metiers.