Analysis of Floral Scent Component of Three Iris Species at Different Stages

Abstract

The research investigates the variations in floral scent composition among different species and developmental stages of Iris plants: Iris uniflora, Iris typhifolia, and Iris sanguinea. The study analyzes the fragrance components by utilizing electronic nose technology in tandem with headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). Principal component analysis (PCA), linear discriminant analysis (LDA), and loading analysis are applied to discern whether floral scents of the same Iris species at distinct stages could be differentiated. The results show that the electronic nose significantly distinguishes the aromas from different stages and that there are differences in aroma composition. Gas Chromatography-Mass Spectrometry confirms significant differences in volatile components regarding the three Iris species, with common compounds like alcohols, aromatics, and aldehydes present throughout stages. Notably, nonyl aldehyde, capric aldehyde, 2,4-di-tert-butylphenol, and n-heptadecane are consistently found. Cluster analysis reveals a grouping of decay stage samples of Iris typhifolia and Iris sanguinea due to terpene and ester abundance. Nonyl aldehyde significantly contributes to the aroma profiles of all species, owing to its high odor activity value. The significant content of volatile compounds in these Iris varieties suggests economic and medicinal potential beyond ornamental value, providing references for the development of Iris-scented products, aromatherapy, and the extraction of pharmacologically active substances from Iris.