title: Chemical compositions and antibacterial activity of the leaf and stem oils of Piper porphyrophyllum (Lindl.) N.E. Br.
abstract: The essential oils obtained by hydrodistillation from the fresh leaf and stem of Piper porphyrophyllum N.E. Br. were analyzed by GC and GC/MS. Thirty four constituents were identified in the leaf oil, while thirty eight constituents were identified in the stems oil. The most abundant components in the leaf oil included bicyclogermacrene (14.7 %), α-copaene (13.2 %) and β-phellandrene (9.5 %) while sabinene (15.5 %), bicyclogermacrene (12.3 %) and α-copaene (8.1 %) were the main constituents in the stem oil. The evaluation of antibacterial activity by using micro-dilution method revealed that both oils were moderately active against all the Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis) and Gram-negative bacteria (Pseudomonas aeruginosa, Pseudomonas putida and Escherichia coli) with minimum inhibitory concentration (MIC) values in the range 125-1000 µg/ml.
authors.affiliation: Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia (UTM), 81310 Skudai, Johor, Malaysia.
authors.forename: Wan Mohd Nuzul Hakimi Wan
authors.initials: WM
authors.lastname: Salleh
authors.affiliation: Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia (UTM), 81310 Skudai, Johor, Malaysia.
authors.forename: Farediah
authors.initials: F
authors.lastname: Ahmad
authors.affiliation: Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia (UTM), 81310 Skudai, Johor, Malaysia.
authors.forename: Hasnah Mohd
authors.initials: HM
authors.lastname: Sirat
authors.affiliation: School of Chemistry and Environment Studies, Faculty of Applied Sciences, Universiti Teknologi MARA (UiTM) Sarawak, Jalan Meranek, 94300 Kota Samarahan, Sarawak, Malaysia.
authors.forename: Khong Heng
authors.initials: KH
authors.lastname: Yen
keywords: Piper porphyrophyllum; antimicrobial activity; chemical compositions; essential oils