Study of variation in floral metabolite profiles of Tabernaemontana divaricata (L.) R. Br. genotypes based on gas chromatography- mass spectrometry

Tabernaemontana divaricata (L.) R. Br. is a popular ornamental shrub. Each and every part of the plant is medicinally very significant. The floral metabolome of it remains largely uncharacterized. In this study, gas chromatography-mass spectrometry (GC-MS) analysis was performed on methanolic floral extracts from four genotypes leading to the identification of 68-99 metabolites out of which 30 metabolites based on notable peak area percentages from all 4 genotypes were taken to further study. The detected compounds included methyl salicylate, myo-inositol, cis-vaccenic acid, squalene, geraniol, phytol, n-hexadecanoic acid and benzene derivatives. The metabolites belong to diverse chemical classes such as esters, terpenoids, lactones, fatty acid derivatives and aromatic alcohols. These metabolites are well known for their antioxidant, antimicrobial and anti-inflammatory properties. Chemometric tools including principal component analysis (PCA), hierarchical clustering and Venn diagrams revealed clear genotype-specific variation and distinct grouping based on metabolite profiles. Whereas previous reports have focused on alkaloid-rich leaf and latex extracts, this study provides first characterization of the floral metabolite diversity and identifies genotype specific metabolic profiles of T. divaricata, thereby enhancing its chemotaxonomic understanding. Potential applications in breeding, fragrance or therapeutics are suggested as future avenues for research.