Chemical composition and antibacterial activity of essential oils from Struchium sparganophora Linn. Ktze Asteraceae

Struchium sparganophora Linn. Ktze Asteraceae is a culinary herb that is consumed in the Western part of Nigeria and has wide medicinal uses in traditional medicine. The present study was carried out to determine the chemical composition of the oils from its leaf and stem and their antibacterial activity.

Essential oils were collected from the leaf and stem of Struchium sparganophora by hydrodistillation and analysed by GC and GC-MS. The antimicrobial activity was tested against Gramm negative (G-ve) and Gramm positive (G+ve) microorganisms obtained from the Medical Microbiology Unit, University College Hospital (UCH), Ibadan, Nigeria.

Forty-six compounds were identified in the leaf representing 95.3% of the total oil while fifty-five compounds were identified in the stem representing 93.5% of the oil. ß-caryophyllene, Germacrene A, a-humulene and Germacrene D represented the major components in both oils.

Antibacterial activity of the oils against certain strains of bacteria showed that the essential oil from the leaf had activity ranging from 9.0 ± 1.0 to 14.3 ± 2.55 mm while the essential oil from the stem had activity ranging from 18.5 ± 2.2 to 20.0 ± 0.0 mm for both G-ve. and G+ve microorganisms respectively.

Keywords; Essential oils, β-caryophyllene, Germacrene A, antibacterial activity.