SESQUITERPENOID SPIRO COMPOUNDS FROM POTATO-TUBERS INFECTED WITH PHOMA-FOVEATA AND FUSARIUM SPP

The main sesquiterpenoids found in potato tubers infected by the fungi Phoma foveata and Fusarium spp. were identified as the C-1' epimers o f methylethyl)-6,10-dimethylspiro[4,5]dec-6-en-8-one and their 2'-O-be ta-D-glucopyranosides, by using NMR techniques, conformational analysi s, CD measurements and chemical methods. The 1'S epimers predominated. The pattern of post-infectional metabolites in the stress zone and my celia as well as in healthy tuber tissue was monitored by HPLC. (C) 19 98 Elsevier Science Ltd. All rights reserved.