The Genus Difference Research Of Chimonanthus Flowers Based On Chemical Composition

Chimonanthus Lindl,affiliated to the Calycanthaceae,is Chinese edimic specie,which mainly distribute in the southeast of China.The plant is widely used for landscaping,and part of leaves and flowers can make tea or be used medicine.Chimonanthus consists of Ch.praecox,Ch.nitens Oliv,Ch.salicifolius S.Y.Hu,Ch.Zhejiangensis M.C.Liu,Ch.grammatus M.C.Liu.The extraction method of Chimonanthus praecox leaves was optimized,the total flavonoids and DPPH free radical scavenging of different extraction phase from Chimonanthus flowers were determined,and the chemical composition and antioxidant activity of flowers were analysed.The results are showed as follows:1.The effects of ethanol concentration,ultrasonic time and ultrasonic temperature on the extraction yield of total flavonoids,total phenol and DPPH free radical scavenging from leaves were determined using Response Surface Methodology(RSM).The results showed that the optimum technological conditions were: 81.83 %-84.83 % of ethanol concentration,33.31 min-36.62 min of ultrasonic time,42.55 ℃-49.15 ℃ of ultrasonic temperature.The actual value of total flavonoids,total phenol and DPPH free radical scavenging of the optimal extraction conditions were close to the theoretical value.The results suggested that the optimum process conditions generated from RSM were reliable and practical.2.By optimizing treatment conditions of the samples,the best extraction conditions of SPME were 1.2 g of sample weight,45 min of adsorption time,3 min of desorption time,70 ℃ of heating temperature.By GC-MS qualitative analysis,46 kinds of volatile components were identified from 5 species of Chimonanthus,and Ch.Praecox contained 37 kinds,and there were 41 kinds existed in the both Ch.Grammatus and Ch.Nitens,Ch.Zhejiangensis and Ch.salicifolius contained 43 and 36 kinds respectively,and there were 24 kinds of common components.The main volatile components of 5 species of Chimonanthus flowers were terpenoids,and the difference of 5 species was great.The ingredients from Ch.nitens,Ch.salicifolius and Ch.Zhejiangensis flowers were similar,so they had the same use value.However,the aroma of Ch.Grammatus and Ch.Praecox was different,and the volatile components of them were distinctly different from those of the other 3 species,so the use value of them should be discriminatory.This research provided a theoretical reference for classification of the 5 species of Chimonanthus and the development and utilizing of Chimonanthus flowers.3.The difference of flavonoids content of 5 kinds of plant flowers was significant,and the flavonoids content of Ch.Praecox was highest(69.21 mg/g of 70% ethanol extracts),the content of Ch.nitens was following.In the different extraction phase,the flavonoids content and the scavenging free radicals ability of n-butanol phase and ethyl acetate phase showed more stronger,which showd there was a positive correlation between antioxidant capacity and total flavonoids content..4.The different of chemical composition of Chimonanthus flowers was identified and compared by HPLC and LC–UV–ESI-MS,there were 9 identified compounds: Scopoletin-7-O-β-D-glucoside,Scopoletin,Rutin,Isoquercitrin,Kaempferol-3-O-β-D-rutinlside,Kaempferol-3-O-β-D-glucoside,Quercetin,Kaempferol,Emodin.The 9 compounds were quantitative analysed,and the ranges of content were: 0-2.16,0-0.23,1.94-59.74,0.14-0.97,0.59-8.13,0.11-0.68,0.23-1.92,0.07-0.97,0-0.33 respectively.The differenr of compounds of Chimonanthus was obvious,the content of Rutin was the highest,and Scopoletin-7-O-β-D-glucoside,Scopoletin were not detected in the Ch.praecox flowers.5.The antioxidant activity of compounds was analyzed by the DPPH-HPLC method,which the peak areas were compared before and after adding DPPH,the peak of isoquercitrin was nearly disappearance,the peak areas of rutin,quercetin,and kaempferiae were drop a lot,which showed the antioxidant activity of these compounds was stronger.Through the determination of DPPH free radical clearance,the DPPH free radical clearance activity of Rutin,Quercetin,Kaempferiae,and Isoquercitrin was strong(all of SAR were more than 50 %).The same results of DPPH free radical scavenging and DPPH-HPLC method verified the feasibility of DPPH-HPLC method.