Production of mevalonic acid by fermentation.

The purpose of this investigation was to select microorganisms that produce substantial quantities of mevalonic acid and to develop an economic fermentation process. To screen for mevalonic acid-producing microorganisms, it was necessary to improve the method for the quantitative determination of this acid. The biological assay was modified by shortening the incubation time and simplifying the procedure. The principle of the assay is based on the essential mevalonic acid requirement of the organism Lactobacillus heterohiochii for growth. Screening was carried out by selecting high mevalonic acid-producing organisms from various type cultures. Endomycopsis fibuliger was chosen for medium development studies, and 939 mug of mevalonic acid per ml was produced in the culture filtrate after modifications of medium and fermentation conditions.