Ascorbic acid biosynthesis in higher plants and micro-organisms

In addition to naturally synthesised L-AA, over 80,000 tonnes of synthetic L-AA are produced each year and used to manufacture vitamin supplements, in the food processing and beverage manufacturing industries as well as a supplement in animal feeds. The majority of L-AA is currently produced by primarily chemical means via the seven-step Reichstein process. Alternative methods use prokaryotic fermentations to synthesise intermediates of the Reichstein process, as these industrially useful micro-organisms lack the ability to synthesise L-AA. However, progress in our understanding of L-AA biosynthesis in plants have resulted in the development of alternative strategies for the synthesis of this important commodity with a global market in excess of U.S. $ 600 million.