Discrimination of Syzygium polyanthum Cultivars (Wight) Walp Based on Essential oil Composition

Myrtaceae has been considered as the richest species with the genus Syzygium having approximately 120 species in Malaysia. The aerial part of Syzygium polyanthum is largely consumed as ulam with the aim of treating diverse ailments and enhancing appetite in Peninsular Malaysia. The richness of the species in the niche has resulted in the taxonomic misidentification which caused a serious problem in biodiversity management and development of natural products. The study was aimed to discriminate the two cultivars of S. Polyanthum (Serai Kayu and Serai Kayu Hutan) based on the chemical composition of their essential oil. The volatile compounds were distilled from the aerial parts using Hydrodistillation. Up to 0.4% and 1.6% (v/w) were percentages of the oil yield obtained from Serai Kayu and Serai Kayu Hutan leaves, respectively. The GC/MS analysis revealed the presence of 40 and 29 compounds amounting to 70.29% and 95.15% in Serai Kayu and Serai Kayu Hutan, respectively. Alpha-Pinene (38.46%), Octanal (21.01%) and (E)-Methyl-cinnamate (7.21%) were the main constituents of Serai Kayu while in Serai Kayu Hutan Z-Methyl-cinnamate (39.18%), Terpinolane (23.63%) and Spathulenol (3.98%) were the major constituents. Compounds below 1% were considered to be minor constituents in both the species. The study documents the first chemical composition of the cultivar Serai Kayu Hutan. The analysis of the chemical content has added taxonomic information to the genus Syzygium and had provided the baseline information for natural product development.