The Extraction, Analysis And Antioxidant Research In Peony Essential Oil

Peony (Paeonia suffruticosa Andrews) resources are rich in China, especially Heze which is the home of peony. Current there are a lot of peony waste because of the limited development of peony resources. Peony essential oil has the advantages of green and no pollution as a natural plant essential oil, and there are many bioactivator which are beneficial to beauty and health for human in it. Therefore, peony essential oil will be the hot spots of development. Doing this research on extraction, composition and antioxidant activity of peony essential oil produced in Heze will be a useful exploration for peony industrial development in Heze. The main research results were as follows:1.The extraction conditions (different distillation time, liquid/solid ratio and NaCl concentrations) of Hydro distillation extraction (HDE) were studied according to the combination of single factor experiment and Orthogonal Experiment Design(OED). The results showed that distillation time has a great influence on the yield of peony essential oils. The optimal extraction conditions were established as a distillation time of 4h, liquid/solid ratio of 15mL.g-1 and NaCl concentrations of 5%, with an expected yield of 0.4274%.2.The extraction conditions (different distillation time, liquid/solid ratio, NaCl concentrations and ultrasound time) of Ultrasonic assisted hydro distillation extraction (UAHDE) were studied according to the combination of single factor experiment and OED. The results showed that NaCl concentration has a little influence on the yield of peony essential oils. The optimal extraction conditions were established as an ultrasound time of 20min, distillation time of 3 h, liquid/solid ratio of 15mL.g-1, with an expected yield of 0.6336%.3.The extraction conditions (different solvents, burden granularity, pressure, holding time and liquid/solid ratio) of ultrahigh pressure extraction (UPE) were studied according to the combination of single factor experiment and Response Surface Methodology(RSM). The results showed that petroleum ether was the best solvent to extract peony essential oil. The influences on the yield of peony essential oils were pressure (X3)> burden granularity(X1)> holding time(X2)>liquid/solid ratio (X4).The optimal extraction conditions were established as burden granularity of 70 meshes, holding time of 12min, pressure of 330MPa and liquid/solid ratio of 12mL/g, with an expected yield of 0.7265%.4.Composition of peony essential oils was identified and analyzed by gas chromatography mass spectrometry technology (GC-MS). The composition of fresh and dried peony essential oils extracted by UAHDE were compared. The results showed that there were 11 kinds of mutual compounds in two kinds of essential oils. Fresh peony essential oils contain a small amount of phenols, nitrogen compounds and more composition of the small molecular weight contrasted with dried peony essential oils. However, dried peony essential oils contain more aromatic hydrocarbons than fresh peony essential oils.5.The composition of peony essential oil in the extraction by using HDE, UAHDE and UPE were compared. The results showed that there were 42,44 and 54 kinds of compounds, respectively. Peony essential oils mainly contain esters, terpenes, alkanes, aromatic hydrocarbons, acids and alcohols. And there were 18 kinds of mutual compounds in two kinds of essential oils. The composition of peony essential oil extracted by UPE were most among three kinds of methods. Aldehydes and phenols were not detected by HDE and phenols, ketones were not detected by UAHDE compared with UPE. Moreover, such 10 types of components were first extracted as a Beta. Fenchyl alcohol, Nerol, Nonanoic acid, (E)-Cinnamaldehyde, Citronella,9,10-dehydro-Cycloisolongifolene, Dibenzofuran, Neophytadiene, Hexadecanoic acid, ethyl ester, Z-5-Nonadecene.6.The antioxidant activities of peony essential oil were assessed by means of DPPH system, · OH as well as reduction power. The results showed that the sequence of total antioxidative capability was essential oils extracted by UPE> essential oils extracted by UAHDE> essential oils extracted by HDE.