The chemical compositions of the leaf and bark oils of Xylopia caudata were examined by co-chromatography with authentic samples on a polar capillary column (PEG 20M) and a non polar capillary column (SE-30), GC/MS and further comparison with Kovats Retention Index. The essential oils were mainly made up of monoterpenoids. The major components in both oils were β-pinene, α-pinene, limonene and a-terpineol which collectively represented 90% and 69% of the leaf and bark oils respectively.
Kandungan kimia minyak pati daun dan kulit kayu Xylopia caudata telah dikaji secara ko-kromatografi dengan sampel tulen di atas turus rerambut polar (PEG 20M) dan turus rerambut kurang polar (SE-30), KG/SJ dan perbandingan dengan Indeks Penahanan Kovats. Sebahagian besar minyak pati tersebut terdiri daripada sebatian monoterpenoid. Komponen utama yang terdapat dalam kedua-dua minyak pati tersebut adalah β-pinena, α-pinena, limonena dan a-terpineol yang mewakili 90% dan 69% daripada minyak pati daun dan kulit kayu masing-masing.
The evolution of cosmetic products results in the growing demands for cosmetics that are preservatives free. Plant essential oils were found to be a promising antimicrobial and also antioxidant agent. In this study, Cymbopogon citratus (lemongrass), Laurus nobilis (bay leaf) and Backhousia citriodora (lemon myrtle) essential oils were selected and evaluated for their antimicrobial properties. It was found that Laurus nobilis exhibited strong antimicrobial activity against the selected bacteria Streptococcus saprophyticus (ATCC 49619), Streptococcus aureus (ATCC 22923), Streptococcus pyogenes (ATCC 29436), Pseudomonas aeruginosa (ATCC 13048), Klebsiella pneumoniae (ATCC 700603), Escherichia coli (ATCC 22922) with MIC ranging between 7.8 ug/mL to 250 μg/mL. The antioxidant activity of selected essential oils was determined by antioxidant assays which were 1,1-Diphenyl-2-picrylhydrazyl assay (DPPH), determination of ferric reducing antioxidant power assay (FRAP) and β-Carotene/linoleic acid bleaching assay. Backhousia citriodora and Laurus nobilis showed the highest antioxidant activity.
n-Octanal and β-Selinene were identified to be the major components with peak area of 26.37 % and 13.92 % respectively in secondary metabolites analysis by Gas Chromatography-Mass Spectrometry (GCMS).