Sesquiterpenoids from hexane extract of Echinophora platyloba aerial parts

Background and objectives: Echinophora platyloba is used for flavoring foods, cheese and yoghurt. Despite several pharmacological studies on the plant, no attempt has been made to isolate the non-volatile secondary metabolites and assess the antimicrobial effects. So, phytochemical investigation seems to be useful for better use of this plant. Methods: E. platyloba aerial parts were extracted with hexane by Soxhlet apparatus and fractionated. The subfractions were purified using HPLC and analyzed by 1HNMR, 13CNMR, COSY and Mass spectroscopy. Different extracts with hexane, dichloromethane and acetone solvents through were prepared Soxhlet method. The extracts were individually tested against three gram-Negative (E. coli, S. flexneri, A. baumannii) and two Gram-positive bacteria (S. aureus, E. fecalis) by microdilution methods. The susceptibility of E. coli, S. flexneri, A. baumannii, E. fecalis isolates to gentamycin and S. aureus to oxacillin was assessed. Results: A branch of fatty acids and triglycerides were obtained along with polyoxygenated sesquiterpenoid, vaginatin. MIC of the hexane extract against bacterium 1 was 512 µg/mL. MIC of ethanol extract against bacterial 1 to 4, were 2048, 512, 2048 and 2048 µg/mL, respectively. MIC of other extract were equal higher than 4096 µg/mL. Conclusion: Vaginatin was reported for the first time as a sesquiterpenoid from Echinophora genus. The ethanol extract was the most and dichlormethane extract the least effective extract. A. baummannii was the most susceptible organism to the hexan extract compared to other extracts.