Hydrocarbons and monoesters of propolis waxes from Brazil

Abstract - Waxes of 23 samples of propolis of Apis mellifera mostly from Brazil yielded monoesters as main constituents, followed by hydrocarbons. The methyl and acetyl esters of the carboxylic acids and alcohols, respectively, derived from the monoesters, and the hydrocarbons were analysed by gas chromatography/electron impact-mass spectrometry. The hydrocarbons comprise n-alkanes and alkenes, the main homologues being C ₂₇H₅₆, C₂₉H₆₀, C₃₁H ₆₄ and C₃₃H₆₈. iso-Alkanes in low amounts were found in some samples. The main carboxylic acids are C_16:0, C_18:0, C_18:1. The primary alcohols range from C₂₄ to C₃₄, C₃₀ being generally the main constituent. A wide variation in the distribution of hydrocarbons, acids and alcohols was found comparing one sample with another. The composition of propolis wax is similar to that of comb wax, which suggests that propolis waxes are probably secreted by the bees, rather than originating from plants. © Inra/DIB/AGIB/Elsevier, Paris