The contents of total ashes and ethanol soluble substances were determined for propolis samples from species of two Meliponini genera: Melipona and Scaptotrigona. All Melipona samples corresponded to geopropolis (propolis containing aggregated soil material), with ash contents above 40%. Only one species of Scaptotrigona was shown to produce geopropolis, but with ash content (12%) much lower than Melipona samples. In Melipona a high negative correlation was observed between ash and ethanol solubles. Not only aggregated soil may contribute to lower the content of ethanol solubles. It is hypothesized that wax content may have a similar influence.

Keywords: apidae, stingless bees, melipona, scaptotrigona, propolis, phenolic substances

Propolis is a resinous apiculture product used commercially in industries of food and hygiene products, as well as in traditional and popular medicine. Nearly all marketed types of propolis derive from honey bees (Apis mellifera). While bee laborers produce honey from nectar collected from a wide diversity of plant species, they elaborate propolis by mixing resin from a relatively low diversity of plant species, which they mix with beeswax.^1,2 Propolis has complex chemical composition. Most propolis types contain predominantly phenolic compounds, a class of secondary metabolites known to exert a wide diversity of biological activities.^3,4 Among members of the family Apidae, Apis mellifera is not the only propolis producer species. Many species of stingless bees (Meliponini) also produce propolis, often with composition similar with honey bee propolis.⁵ Meliponine propolis has been shown to exert a diversity of biological properties,⁶ including antitumor activity.⁷ There is a high diversity of meliponines in tropical habitats, with the number of species in the New World reaching nearly 400. They are relevant pollinators of native plants and crops.⁷ Main meliponine genera in Brazilian biomes are Melipona, Scaptotrigona and Tetragonisca. Comparing with honey bees, the productivity of meliponines is considerably low. For this reason, meliponine propolis is seldom commercialized. However, in recent years there has been a growing interest aiming to produce meliponine honey and propolis. In several parts of Brazil, meliponiculture has been practiced by leisure or desir