Biochemical analysis of petals in Rosa species (Rosaceae) from Iran using gas chromatography-mass spectrometry

Abstract

This study investigates the phytochemical composition, with a focus on alkane profiles, of petals from eight Rosa species native to Iran using gas chromatography–mass spectrometry (GC-MS). Flowers were collected from healthy individuals in wild populations across diverse regions of Iran, including the Alborz mountain range, at altitudes between 1546 and 2597 m. The dried petals were extracted using the Bligh and Dyer method and analyzed with GC-MS under standardized chromatographic conditions. The analysis revealed 81 distinct phytochemical compounds across the studied species, including a range of alkanes. Identified compounds included 32 alkanes, 4 triterpenoids, 4 phytosterols/steroids, 3 fatty acid methyl esters, 3 phenols, 2 phthalate esters, 2 alkenes, 1 oxaspiro compound, and other minor constituents such as alkylbenzenes, benzoate esters, and vitamin E. Alkane chain lengths ranged from C₁₂ to C₄₄, with interspecific variation in both diversity and abundance. Multivariate statistical analyses, including cluster analysis (UPGMA), Pearson correlation, and principal component analysis (PCA), were applied to assess interspecific chemical variation and species relationships. Pearson correlation analysis revealed strong positive associations between species such as R. beggeriana and R. iberica (p < 0.001), as well as among specific alkane compounds (r > 0.92, p < 0.0001), suggesting shared biosynthetic pathways. A significant finding of this study is the first report of 7,9-di-tert-butyl-1-oxaspiro[4.5]deca-6,9-diene-2,8-dione in Rosa petals. These results enhance the chemotaxonomy of the Rosa genus and suggest potential therapeutic and nutritional uses for wild Rosa species.