Studies On The Isolated And Antibacterial Activity Of The Flavonoids And Volatile Oil From Dalbergia Odorifera T. Chen

The dried heartwood of the trunk and root of Dalbergia odorifera T. Chen was named "Jiangxiang" in Chinese traditional medicine. It mainly contained flavonoids and volatile oil. Modern pharmacological research has proved that it possessed anti-inflammatory, antitumor, anticoagulant, vasodilative, antihyperlipidemic and antioxidant activities. In this paper, the ethanol extract of D. odoriferae were isolated and identified, and their antibacterial activities were evaluated. It is very important to the development and sustainable utilization of this resource.1. Extraction, fractionation and identification of the flavonoids:Thirteen compounds were isolated from the EtOAc fraction of ethanol extract of D. odoriferae by column chromatography, and their structures were indentified by physicochemical and spectral data (NMR) as sativanone (1),(3R)-vestitol (2),(3R)-vestitone (3), isoliquiritigenin (4),(3R)-4’-methoxy-2’,3,7-trihydroxy-isoflavanone (5), carthamidin (6), liquiritigenin (7),3’-hdroxyformononetin (8),(3R)-2’,3’,7-trihydroxy-4’-methoxy-isoflavanone (9),3’-hydroxymelanettin (10), butein (11), sulfuretin (12) and fsetin (13).2. Antibacterial activity of the compounds:The antibacterial activities of all the compounds were examined by the filter paper disc agar diffusion method. Compounds1-5showed inhibitory activity against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA). Compounds6and9showed inhibitory activity against S. aureus. Compound12showed inhibitory activity against MRSA. Compounds1-7、9and12showed inhibitory activity against Ralstonia solanacearum. Compound2exhibited the strongest antibacterial activity. Thus, flavonoids were defined as the active compounds of D. odoriferae.3. Chemical compositions and antibacterial activity of the volatile oil:The volatile oil from the heartwood of D. odoriferae was extracted by hydrodistillation in a Clevenger-type apparatus, and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of sixteen compounds, constituting over98.04%of the total oil, were identified from the volatile oil. The major components of volatile oil were caryophyllene oxide (54.22%),7,11-dimethyl-10-dodecen-1-ol (14.11%),6,11-dimethyl-2,6,10-dodecatrien-1-ol (10.24%) and nerolidol (10.22%). In addition, antibacterial activity of the volatile oil was evaluated. The oil showed activity against S. aureus and MRSA.