Fusarium sambucinum Fuckel 8099-1 was grown on Czapek-Dox peptone-supplemented medium at 15°C for 14 days, and the cultures were investigated for diacetoxyscirpenol (DAS) production by liquid-liquid extraction and gas chromatography. The addition of 150 mg of sorbic acid, a tricarboxylic acid cycle inhibitor, per liter stimulated both fungal growth and DAS production. Among the 13-hydroxy-13-methylglutaryl coenzyme A precursors tested, isovaleric acid completely inhibited fungal growth and DAS production, ethyl isovalerate did not support a significant increase in DAS production, and L-leucine partially inhibited DAS production, showing that L-leucine and isovaleric acid catabolisms do not induce trichothecene biosynthesis. Solid particles (cork powder) were necessary for DAS production in stationary cultures but did not influence DAS production in shaken cultures. Shaking strongly stimulated DAS production and fungal growth.

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The structure of the hexose region of the lipopolysaccharide from M206 strain, a mutant of Salmonella typhimurium having reduced virulence, was partially determined. Immunological tests indicated cross‐reactions of anti‐(M206) antiserum with wild‐type C5 and Ra mutant strains. Data obtained on chemical composition, periodate oxidation, acetolysis, methylation and analysis by gas chromatography/mass spectrometry show that M206 type lipopolysaccharide contains the common core polysaccharide of Salmonella which was substituted in position 4 of the subterminal glucose unit by a disaccharide: d‐glucosyl 1 → 3 d‐galactose. This substitution is probably related to the slight virulence of M206 strain.