Electrophoresis characterization of proteins in honey to establish their entomological origin

Melipona beecheii and Trigona spp. are the most important stingless bee species in Mexico due to the honey yields and reported medicinal properties. In order to increase production and to enhance a broader market for stingless bee honey as natural and organic products, it is necessary to establish parameters to determine the entomological origin and authenticity. The identification and quantification of sugars and secondary metabolites using chromatographic techniques and nuclear magnetic resonance have been proposed to authenticate the entomological origin of honeys. However, these techniques are costly in terms of reagent consumption and maintenance. In this chapter, the electrophoretic characterization of proteins in honey is proposed as an analytical method to establish the entomological origin of honey. Honeys of Apis mellifera, Melipona beecheii and Trigona spp were collected in Yucatan, Mexico. SDS-PAGE of honey proteins and bee midgut extracts have distinctive bands, which accurately distinguish the entomological origin of the sample. The SDS-PAGE pattern of A. mellifera honey proteins showed three bands with molecular weights between 10.2 and 74.8 kDa, M. beecheii honey proteins showed five bands with molecular weights between 6.1 and 97.0 kDa and Trigona spp honey proteins showed nine bands with molecular weights between 9.3 and 86.7 kDa. These differences observed between electrophoretic patterns could result from physiological differences between A. mellifera and stingless bees (M. beecheii and Trigona spp.). The protein electrophoretic patterns of stingless bee honeys could be used to establish both its authenticity and entomological origin.