Studies On Separation And Chemicals Analysis Of The Essential Oil And The Flavonoids From Rosa Laevigata Michaux

Rose laevigata,one of the affinal drug and diet substances in China,is abundantly distributed in south and southwest of China.The fruit of Rose laevigata is used to treat diarrhea,cough,diabetes,hypertens ion,cancer,tumors and other disease in China as a medicine.Because of the abundant natural substances in the fruit,this plant comes to be a remarkable fruit recently.The essential oil and the flavonoids from the fruit of Rosa laevigata were studied in this paper to provide theoretical basis for further its research and application.The results were as follows:1.Chemical composition and aroma of essential oil from the fruit of Rosa laevigata obtained by steam distillation was analyzed by Gas Chromatography-Mass Spectrumeter(GC-MS)and Gas Chromatography-Olfactometry(GC-O).Fifty eight compounds in the essential oil,accounting for 99.97%,were identified,in which palmitic acid(16.49%),cis-13-Octadecenoic acid(16.31%)and linoleic acid(13.93%)were the main compounds.The overall aroma of the oil was complex,smelled waxy,heavy refreshing and sweet,and strong woody with a tiny tea.24 aroma compounds were identified by the technique of GC-O with a posterior intensity method.The key active odor of this essential oil is myristic acid.2.Ultrasonic extraction conditions of flavonoids from Rose laevigata was optimized by response surface methodology(RSM).Based on the single-factors experiments,factors such as ratio of liquid to raw material,ethanol concentration,ultrasonic power,ultrasonic time and extracting time on the extraction yields were studied,Box-Behnken design was used to optimize the ultrasonic extraction process.Results showed that the optimum conditions were ratio of liquid to raw material 1:22(g/m L),ethanol concentration at 55%,ultrasonic power 400 W,ultrasonic time 3min and extraction time 120 min,and the highest yield of flavonoids reached 13.25%.3.Separation and purification of the flavonoids from Rose laevigata were carried out by AB-8 macroporous resin.Through the dynamic adsorption and dynamic experiments,the optimum process parameters were as followed: the sample concentration 0.4 mg/m L,the volume of sample 2 times of column volume,sample flow velocity 0.8 m L/min,elution concentration 90% ethanol and eluent volume 4 times of column volume.Under this condition,the purity of flavonoids from Rose laevigata reached 45.63%.The antioxidant activities of crude flavonoids were evaluated by DPPH,hydroxyl radical and reducing power.The results show that the flavonoids have a good oxidation resistance.