Fumonisins are toxic 2^0 metabolites ● Reduced linear polyketides ○ Multiple functional groups ● Produced by multiple fungal genera ○ Fusarium verticillioides and Aspergillus niger ● Inhibits sphingolipids biosynthesis Fumonisins are toxic to mammals ● Equine Leukoencephalomalacia ● Porcine pulmonary edema ● Neural tube defects and esophageal cancer in humans Threat of mycotoxin contamination in Canadian Vineyard ● Grapes in vinyard ○ grapes susceptible to fungal infections. ■ humid or wet conditions ● Fungal contamination ○ Aspergillus ○ Penicillium ○ Botrytis ○ colonization can occur during growth ● Fungal cultures ○ Isolated from infected grapes ○ produce secondary metabolites ■ Mycotoxins ● Mycotoxin structures ○ Ochratoxin A ○ Patulin ○ persist in wine and grape derived products ● FB2 FB4 FB6 ○ Fumonisin variants with modification in structure ● FLa2 FLa4 ○ fumonisin forms with OH group (hydroxyl) ● FPy2 FPy4 ○ fumonisin breakdown products with C=O group(Carbonyl) Since the highest is FLa4, it is the most abundant derivative ● Long chain sphingolipid backbone with Oh and COOH groups ● Could be variations defined with R groups ○ FB4: Retains amine groups ○ FLa4: Hydrolyzed with hydroxyl group ○ FPy4: Oxidation form with carbonyl group ● Fumonisins: toxic secondary metabolites ○ interfere with sphingolipid metabolism