Immunochemical authentication of manuka honey using a monoclonal antibody specific to a glycoside of methyl syringate
Leptosperin, a novel glycoside of methyl syringate, is exclusively present in manuka honey derived from the Leptospermum species Leptospermum scoparium. Quantification of leptosperin might thus be applicable for authentication of the honey. The concentration of leptosperin has high linearity with antibacterial activity. We established a monoclonal antibody to leptosperin
8 and characterized the antibody by competitive ELISA in detail, comparing the results with those of the present HPLC method for validation. The antigen in manuka honey was confirmed as leptosperin by HPLC fractionation with quantitation by ELISA. Leptosperin contents in 50 honey samples were analyzed by established ELISA, which can handle 20 samples (duplicate) on one 96-wells plate. Significant coincidence with the chemical quantitation was observed. Immunochemical quantitation of leptosperin would be an economical and facile method for possible authentication of manuka honey, allowing many honey samples to be processed and analyzed by ELISA simultaneously.