1. To measure the kinetics of biodegradation of veterinary fluoroquinolone drugs in natural matrices.
2. To identify the potential metabolites produced by fungi from fluoroquinolones.
3. To assess the residual antibacterial activiy and potential risks of the metabolites formed from these drugs.

FY 2000 Accomplishments:

1. Three fungi were shown to transform a model phenothiazine drug, Nacetylphenothiazine,to N-acetylphenothiazine sulfoxide, phenothiazine sulfoxide phenothiazin-3-one, phenothiazine N-glucoside, and phenothiazine.
2. The fungus Mucor ramannianus was shown to transform the veterinary fluoroquinolone drug enrofloxacin to enrofloxacin N-oxide, N-acetylcipro-floxacin, and desethylene-enrofloxacin.
3. Methods for preparing food samples for the chromatographic analysis of flavors and off-flavors in foods were reviewed.
4. The mycotoxin fusarin C was shown not to have a role in the formation of DNA adducts by Fusarium culture extracts.

FY 2001 Plans:

1. Studies on metabolism of the veterinary fluoroquinolone sarafloxacin by Mucor ramannianus and other fungi.
2. Studies on the method of formation of unusual hydroxyvinylcyclopentenone conjugates from ciprofloxacin and norfloxacin by the fungus Trichoderma viride.
3. Identification of the metabolites produced from norfloxacin and sarafloxacin by Trichoderma viride grown on rice hulls (poultry litter).
4. Isolation of new strains of fungi from litter in poultry houses and screening them for the biotransformation of veterinary fluoroquinolones.