Chemical variability of geopropolis from Jataí, Mandaçaia and mandurí stingless bees

Abstract

Stingless bees (meliponinae) are popularly known as native bees and are important pollinators of many crops. Honey from these insects has a palatable flavor and is sold at higher values than Apis mellifera honey. In addition, beehives from stingless bees are marketed with ornamental and environmental purposes. Despite the economic growth of meliponiculture, studies with meliponinae beehive products are scarce. Stingless bees produce geopropolis which consists of plant resins mixed with soil or clay. In the current study the chemical, qualitative and quantitative composition and the antiradical activity of geopropolis produced by different Meliponinae species occurring in Prudentópolis, Paraná were compared. Antiradical activity, as well as total phenolic and flavonoid contents were determined. Spectral profiles by UV-Vis Spectroscopy and Mass Spectrometry with Electrospray Ionization (ESI-MS) were compared as well. The effect of the native bee species (Tetragonisca angustula (Latreille), Melipona quadrifasciata quadrifasciata (Lepeletier) e Melipona marginata (Lepeletier)) and the harvest period on the chemical variability of geopropolis was assessed by statistical tools such as analysis of variance (ANOVA) and multivariate analysis (Principal Component Analysis, PCA). It was observed that both investigated effects, bee species and harvest period, significantly affected the levels of total phenolics and flavonoids and the antiradical activity. Additionally, 12 components of geopropolis were identified by UPLCMS/ MS. PCA grouped geopropolis as function of the bee species, indicating that, for the same geographic region, the overall chemical composition of geopropolis is mainly determined by the stingless bee species.