EFFECT OF PH ON PHYSIOLOGY OF METARHIZIUM-ANISOPLIAE FOR PRODUCTION OF SWAINSONINE

The effect of pH on the production of swainsonine and fungal morpholog y at different stages of fermentation of Metarhizium anisopliae was in vestigated. When no control was applied, the pH of the culture dropped from 6.5 to 3.8 within the first 72 hours and the concentration of sw ainsonine reached 43.3 mg l(-1), When the pH was held constant either at the beginning or throughout the fermentation, the maximum recorded swainsonine level was only 8.4 mg l(-1) corresponding with an increase in the formation of pellets. A late pH control applied after 72 hours , resulted in a swainsonine titer of 45.5 mg l(-1). (C) 1998 Federatio n of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.