Analysis of the floral fragrance of Platanthera stricta

Abstract

The qualitative and quantitative composition of the floral fragrance of Platanthera stricta was determined by trapping fragrance components on charcoal or Tenax adsorbents in the field. Analysis (GC-MS) showed the fragrance to consist largely of lilac aldehydes, lilac alcohols and other monoterpene alcohols, monoterpene hydrocarbons (of which α-pinene is the predominant constituent), and aromatic aldehydes and alcohols. Rates of emission of fragrance among mature inflorescences varied greatly ( ca 50—0 μg/hr/inflorescence). Neither charcoal nor Tenax alone effectively trapped the full range of floral fragrance compounds. When Tenax was used as the trapping agent, lilac aldehydes, lilac alcohols, aromatic aldehydes, aromatic alcohols, and some of the monoterpenes were recovered, but α-pinene, a major component of the fragrance, was recovered only in trace amounts. By contrast, α-pinene and lilac alcohols were effectively recovered from charcoal, but aromatic aldehydes and alcohols were poorly recovered, and lilac aldehydes decomposed.