A mixture of esters of higher fatty acids with higher monohydric alcohols or sterols. Waxes may also contain odd-carbon alkanes, long-chain monoketones, β-diketones, β-hydroxyketones, and secondary alcohols.
Waxes are important components of the waxy cuticle covering the stems, leaves, flowers, and fruits of most plants. They are manufactured as oily droplets in epidermal cells, from which they migrate to the outer surface of the plant via tiny canalculi in the cell wall, and crystallize as rods and platelets. Their pattern of deposition is sometimes used as a micromorphological taxonomic character below the genus level. The function of waxes is not fully understood although it seems likely that they are involved in water balance. Plant waxes are obtained on a commercial scale from the leaves of the carnauba palm (Copernica prunifera) and from the stems of Euphorbia antisyphilitica.