Validation of two ELISA kits for the screening of tylosin and streptomycin in honey according to the European decision 2002/657/EC.
Résumé
Antibiotics are mixed with the food of bees to fight against diseases. No maximum residue limits have been set for honey. Recommended concentrations (RCs) have been published by European Union Reference Laboratories for tylosin and streptomycin. The objective of this project was to select and validate enzyme-linked immunosorbent assay (ELISA) kits for the screening of tylosin and streptomycin/dihydrostreptomycin residues to be implemented in the French honey control plan. Four ELISA kits for tylosin and five ELISA kits for streptomycin were evaluated. At the end, one kit each was selected and validated for tylosin (TECNA AB620) and streptomycin (Europroxima). Both ELISA kits for tylosin and streptomycin are specific, robust, fast and easy-to-use tests. The detection capability CC β of tylosin A was less than or equal to 10 µg kg(-1) (half the RC). The CC β of desmycosin (the hydrolysed product of tylosin A in acidic conditions) is approximately 200 µg kg(-1), which is five times the RC for tylosin (20 µg kg(-1)). Thus, this kit is fit for the screening of tylosin A but is unsuitable to detect desmycosin. The detection capability CC β of streptomycin was less than or equal to 10 µg kg(-1) (one fourth the RC). The cross-reactivity with dihydrostreptomycin was equal to 136%. Both ELISA kits were applicable to a wide variety of honey (single flower and multiflower, different floral origins, different geographic origins, different consistencies [liquid or solid] and different colours).