Screening of deodorizing active compounds from natural materials and deodorizing properties of cineole

摘要

Plant extracts were screened to identify novel deodorizing natural products. Deodorizing activity was detected in an aqueous ethanol extract of cluster mallow leaves by measuring headspace gas by GC (deodorizing activity was defined as percent reduction in headspace odorant concentration following deodorant addition in vitro.). The deodorant compound was purified using silica gel column chromatography, and the active principle was identified as 1,8-cineole by GC/MS analysis. 1,8-Cineole strongly deodorized (>90%) a relatively wide range of odorous gases, including 2-nonenal, skatole, dimethyl trisulfide, indole, isovaleric acid, and dimethyl disulfide. The compounds also moderately deodorized (>70%) allyl methyl sulfide, n-butyric acid, allyl mercaptan, and dimethyl sulfide. Organoleptic assessment conducted by sniffing headspace gas showed a reduction in odor score of 1.5 to 3. Correlative relationships were observed between 1,8-cinole's deodorizing activity and odorant molecular weight and boiling point Furthermore, odorants adsorbed onto 1,8-cineole desorbed with increasing temperature, suggesting a physical deodorizing mechanism of cineole. Cineole is known to mask or hide ambient odorants by overwhelming the malodor with pleasant odor. Our study suggests that in addition to odor-masking activity, 1,8-cineole exhibits another deodorizing mechanism in which the gaseous odorant concentration is reduced via adsorption involving physical interaction between 1,8-cineole and odorant molecules. 1,8-Cinole may thus serve as an effective agent for eliminating various unpleasant odors.