S25 - Session P3 - Volatile compounds and aroma evaluation in flower extracts of Rosa × odorata

Authors: Lijun Zhou *, Chao Yu, Qixiang Zhang

Roses are culturally and economically important ornamental plants in the perfume industry. Rosa × odorata , the unique rose species in China, with strong fragrance and abundant variation, played a prominent role in the formation of modern roses' tea-scent and contained diverse volatile organic compounds (VOCs) with commercial applications. Dozens of novel wild tea scented roses were discovered in Yunnan Province, China. This study aimed to identify components extracted from tea scent roses and explore their classification status. Morphological variation and inter-trait correlation analysis based on 16 morphological traits of 22 roses collected from the wild showed a high degree of morphological diversity in R. × odorata germplasm resources and the variation coefficients had a distribution range from 18.00 to 184.04%. Ten typical Rosa materials were examined for their chemical profiles of floral scent at different flowering stages by sensory analysis and DTD-GC-MS (Direct thermal desorption-gas chromatography-mass spectrometry) analysis. Sensory and incense tone compound evaluation revealed five tea scent, one wood honey scent, one damask modern scent and three fruity scent rose samples. Principal components analysis and hierarchical clustering analysis of 88 VOCs suggested that R . × odorata and R. × chinensis may be involved in the evolution of R. sect. complexes that result in characteristic scents. 103 VOCs were detected from three R . × odorata and three R. × chinensis germplasm resources by SPME (solid phase micro extraction)-GC-MS analysis.The production and release of floral VOCs in double flowers were later than those in single flowers. Principal component analysis showed that R. × odorata contained more volatile compounds originated from benzodiazepine metabolic pathway, such as eugenol, methyleugenol, 3,5-dimethoxytoluene, phenyl ethanol. In summary, this study provides a valuable reference for species identification, floral gene mining, cultivation selection of roses and floral improvement breeding of ornamental plants to develop new raw materials for plant essential oil.