No nordeste do Brasil, a abelha-sem-ferrão Trigona spinipes perfura o tronco de espécimens cultivados de Eucalyptus citriodora para a produção de exudatos. A investigação química do extrato etanólico do ninho de T. spinipes permitiu o isolamento dos triterpenos cicloartanos ácido magniferólico e ácido 3 -hidroxi-24-metilenocicloartan-26-óico, além dos flavonóides 3'-metilquercetina, sakuranetina, éter 7-metil campferol, tricetina e éter 7-metil aromadendrina como compostos majoritários. O isolamento de sakuranetina, éter 7-metil campferol e éter 7-metil aromadendrina do ninho de T. spinipes e do exudato de Eucalyptus citriodora, sugere esta espécie como origem botânica dos constituintes do ninho destas abelhas-sem-ferrão no nordeste do Brasil. A caracterização estrutural dos compostos isolados foi realizada utilizando-se métodos espectrométricos e comparação com dados da literatura.In the Northeast of Brazil the stingless bee Trigona spinipes Fabricius injures the tree bark of cultivated Eucalyptus citriodora specimens in order to make them exudate. The chemical investigation of the ethanol extract of an entire nest of T. spinipes allowed the isolation of the cycloartane triterpene magniferolic acid and 3 -hydroxy-24-methylenecicloartan-26-oic acid, besides the flavonoids 3'-methyl quercetin, sakuranetin, kaempferol 7-methyl ether, tricetin and aromadendrin 7-methyl ether as the main compounds. The isolation of sakuranetin, kaempferol 7-methyl ether, and aromadendrin 7-methyl ether from both Trigonas spinipes´nest and the exudate from Eucalyptus, may suggest this species as a botanical origin of the nest constituents of these stingless bee in the Northeast of Brazil. The structural characterization of the isolated compounds was accomplished by spectrometric means and comparison with the literature data.
Keywords:Trigona spinipes nest, cycloartane triterpenes, flavonoids, Eucalyptus citriodora exudate
IntroductionMore than 500 species stingless bees of subfamily Meliponinae are of pantropical distribution, however, the great diversity of species from the tribe Trigonini and all from the trib e Meliponini are found in the Neotropics. Indigenous stingless bee species from South America collect resinous material from plants and mix it with beewax and soil to form "geopropolis" or "divine elixir", terms suggested for the Meliponinae honeys.2,3 In a general way, they build more complex nests than Apis mellifera, although there are a great variety of forms, size and place of construction. The majority of species use closed cavities to build their nests, but some species of the genus Trigona build completely exposed aerial nests with an entrance normally build of wax and mud, and a passage way generally built with geopropolis ending at the storage pots. 4 Until now, chemical reports are concentrated to the honey bee Apis mellifera and only a few information is known about the chemistry of stingless bees, in spite of the estimated number of over 500 Neotropical species.
5Beekeeping of stingless bees or "meliponiculture" ...