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An indirect enzyme-linked immunosorbent assay (ELISA) was developed to detect Fusarium species in foods. Antibodies to proteins extracted from the mycelia of Fusarium graminearum and Fusarium moniliforme (verticillioides) were produced in New Zealand white rabbits. These antibodies detected 13 Fusarium species in addition to the producer strains. Levels of Fusarium semitectum and Fusarium tricinctum strains were below the detection threshold. The specificity of the assay was tested against 70 molds and yeasts belonging to 23 genera. One strain of Monascus species and one strain of Phoma exigua were detected; however, these two molds are not common contaminants of cereal grains or foods and should not interfere with the assay. The indirect ELISA's detection limits for F. graminearum and F. moniliforme were 0.1 and 1 microg of mold mycelium per ml of a cornmeal mixture, respectively. When spores of each mold were added individually to cornmeal mixtures (at ca. 10 spores per g) and incubated at 25 degrees C, these spores were detected by the indirect ELISA when they reached levels of 10(2) to 10(3) CFU/ml after 24 to 36 h. The indirect ELISA developed here shows promise for the detection of Fusarium species in grains or foods.

A novel cyclic dipeptide -cyclo[(S)-His-(S)-NorArg] - has been prepared which catalyzes an enantioselective version of the Strecker amino acid synthesis. The catalyst, when present in 2 mol % quantity in methanol solution, catalyzes the addition of hydrogen cyanide toN-alkylimines to affordα-amino nitriles in high yield and high enantiomeric excess. Furthermore, acid hydrolysis ofN-benzhydryl-α-amino nitriles afforded the correspondingα-amino acids directly. This methodology affords a variety of arylglycines in exceptionally high enantiomeric excess, but aliphatic amino acids were obtained with low enantioselectivity. Current efforts are underway to expand the scope of this reaction, as well as to elucidate the mechanism of catalysis and the roles played by substrate and catalyst in determining the stereochemical outcome of the reaction.

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