Antioxidant Activity And Molecular Microcapsule Of Perilla Frutescens Eessential Oil

Perilla frutescens,widely spread in China,was in the list of stuffs,which were both medicine and food,announced by the China Ministry of Health,and contained many kinds of bio-active substances.One of these substances was Perilla frutescens essential oil(PEO).In this paper,the optimum extracting condition of PEO,the antioxidant ability of the PEO,and the molecular microencapsulation were studied.The researches about Perilla frutescens in this thesis included three aspects:(1)Essential oil was extracted from the leaves by steam distillation(SD) and microwave assisted extraction(MAE),and optimal extraction conditions were achieved as follows:by SD, the ratio of bark powder to water 1:5(w/v),distilling 1.5 hours by vapour,dissolving solution with 5%salt concentration,and the extraction rate is up to 1.1%;by MAE,Power 1000W, extracting time 4 minute,the ratio of bark powder to water 1:10(w/v),and the extraction rate is up to 1.4%.The essential oils were analyzed by GC-MS:by SD and by MAE contained 43 chemical components and 40 chemical components,repectively.The main component is 2-Furyl pentyl ketone,making up 68.30%and 72.89%of the total volatile oil,repectively.(2)The antioxidative activities of PEO was evaluated based on phosphomolybdenum complex,superoxide anion and hydroxyl radical scavenging activities,reducing power and inhibition of lipid peroxidation in linoleic acid.The results revealed that PEO has notable antioxidative activity.Total aldehydes contents of Green and Purple p.frutescens essential oil were 29.32%and 36.69%,respectively,which were determined by free hydroxylamine method.(3)The inclusion interactions of PEO and SEO with cyclodextrins were determined by ultraviolet spectrometry and spectrofluorimetry,respectively.The K value,△G,△H and△S had been discussed;The inclusion complex was prepared by saturated aqueous solution,and characterized by infrared spectrometry.The stability of essential oil in the microcapsules was obviously improved.The structures of the inclusion complex were 1:1.The order that the capability associated with PEO and SEO were 2-HP-β-CD>2-HE-β-CD>DM-β-CD>β-CD andβ-CD>DM-β-CD>2-HE-β-CD>2-HP-β-CD,respectively.