Effects of Cyclodextrins on Deodoration of ``Aging Odor''

Abstract

Hexenal, octenal and nonenal are known causes of unpleasant body odor and are present at markedly increased levels in the middle-aged and elderly. The odor of such unsaturated aldehydes is therefore called ``aging odor''. The present study investigated the effects of cyclodextrins (CDs) on deodoration of crotonaldehyde, pentenal, hexenal, heptenal, octenal, nonenal, decenal, undecenal and dodecenal. α-, β- and γ-CD formed inclusion complexes with the majority of unsaturated aldehydes in aqueous solution. The γ-CD inclusion complex contained the highest amount of guest molecule. One molecule of γ-CD was estimated to include 1 molecule of short chain aldehyde and 2 molecules of long chain aldehyde. Deodorant testing was conducted by headspace gas analysis using sealed vials. All CDs decreased the concentrations of unsaturated aldehyde. With nonenal, the deodorant power of parent CDs was α-CD > β-CD > γ-CD, and that of chemically modified CD was Meβ-CD > HPβ-CD > G2β-CD > MCTβ-CD. CDs were demonstrated to reduce ``aging odor''. Meβ-CD was the most effective type of CD for the deodoration of ``aging odor''.