Some Lipid Constituents of Pollens Collected by Honeybees

Abstract

Sixteen species of bee-gathered and three species of hand-collected pollens, representing ten plant families, were saponified with ethanolic potassium hydroxide, and the saponifiable and non-saponifiable lipid content was gravimetrically determined. The saponifiable lipid in bee-gathered pollens varied from 0·7 to 10·2% and in hand-collected pollens from 1·4 to 10·8%. Values for total lipid content were 1·5–18·9% in bee-gathered pollens and 3·2–17·8% in hand-collected pollens. The non-saponifiable lipid fractions isolated from 10 species of the bee-gathered and 2 species of the hand-collected pollen were analysed for hydrocarbon and for content of sterols and similar neutral compounds, by column chromatography. Bee-gathered pollen contained 0·06–0·58%hydrocarbons and 0·36–3·4% sterol compounds; hand-collected pollen from cottonwood (Populus fremonti) had about the same percentage of hydrocarbons as that from Lombardy poplar (P. nigra), about twice as high a content of sterols and similar neutral compounds, and about three times as much 3-β-hydroxysterol.