EVALUATION ON MGO OCCURRENCE IN APULIAN HONEY

Honey is a natural product highly appreciated for its sweet taste and for its nutritional and therapeutic properties on human health such as antioxidant, antimicrobial, anti-inflammatory and bacteriostatic effects [1]. Biological effects of the honey are determined by its particular physico-chemical composition. In recent years, the researchers' attention has focused on a particular substance contained in some types of honey, the methylglyoxal (MGO), present in high levels of up to 800 mg/Kg in Manuka (Leptospermum scoparium) honey [2], identified like the component responsible for the pronounced “non peroxide” antibacterial activity [3]. Furthermore, MGO is used as a parameter for the authentication of Manuka honey. The aim of the present study was to investigate the occurrence of MGO in citrus honey collected in Apulia Region (SE, Italy) to establish relative concentrations and to recognize if this substance is useful to characterize this product. A total of 30 citrus honey samples were collected during the year 2017 from Apulian beekeepers. The samples were analyzed in triplicate in HPLC-UV with the method proposed by Mavric et al. [2] with some modifications. The results revealed low concentrations of MGO in citrus honey, ranging from 0.3 to 7 mg/kg. Although other authors observed appreciable MGO concentrations in non-Manuka honeys [4], for the Apulian citrus honeys this compound is not a suitable tool for the characterization of the geographical and botanical origin.