Research On The Odor Recognition And Material Basis Of Radix Pseudostellariae Based On Electronic Nose Technology

Objective1.To analyze the odor component from the whole and partial perspective,we use electronic nose and HS-SPME-GC-MS to distinguish the difference of Pseudostellaria Radix among different regions,different habitat processing and different storage time,respectively.So we can discover the related substance in the odor in response to the electronic nose,and then basically explain the reason why the odor of Pseudostellaria Radix is peculiar.2.To make the odor information of Pseudostellaria Radix objective and measurable,and to optimize the best test method for the odor Pseudostellaria Radix.We hope that the link among samples,sensors and volatile compounds can be specified,so we can set an objective,time-saving and measurable method for the odor Pseudostellaria Radix through electronic nose.3.To provide a source of reference for the new version of Chinese PharmacopoeiaMethods1.Production area and Market Research of Radix PseudostellariaeThrough literature review and telephone inquiry,the main planting areas of Radix Pseudostellariae were determined,and the market of medicinal materials was visited on the spot Go to learn about the distribution and specifications of the commodity medicinal materials of Radix Pseudostellariae,and at the same time go to the planting area of Radix Pseudostellariae to investigate the planting and harvesting information,production and marketing of Radix Pseudostellariae2.Sample collection47 batches of fresh Radix Pseudostellariae were collected,including 10 in Anhui,11 in Fujian,13 in Guizhou and 13 in Shandong.According to the primary processing method of producing area in Pharmacopoeia,the herbs were dried and dried after scalding.Knead the dried products,remove the fibrous roots and impurities,clean them,and store the finished products for standby.3.Establish a method for the determination of the odor of Radix Pseudostellariae by electronic noseThrough single factor investigation,the sample quantity,powder particle size,sample quantity in instrument parameters,heating time and temperature were explored and optimized,and finally the suitable electronic nose detection conditions were determined4.Establish the discrimination model of different classifications of Radix PseudostellariaThe odor of Radix Pseudostellariae from different places of production,different places of production and different storage periods was detected.According to the objective odor information obtained,combining with principal component analysis and discriminant factor analysis,the processing method,producing area and storage period of Radix Pseudostellariae were distinguished.5.Establishment of headspace solid phase microextraction gas chromatography-mass spectrometry(HS-SPME-GC-MS)for the determination of volatile components in Radix PseudostellariaeThrough single factor investigation,the extraction head type,extraction heating temperature and extraction equilibrium time were explored and optimized in the headspace solid-phase microextraction test,and finally the detection parameters of HS-SPME-GC-MS were determined.6.Calibration of the common peaks of the Radix Pseudostellariae47 batches of Radix Pseudostellariae were determined by headspace solid phase microextraction gas chromatography-mass spectrometry.The common peaks of Radix Pseudostellariae were determined by comparing chromatograms.Meanwhile,the compound structures of the common peaks were determined by searching NIST 11.0 library and literature7.Correlation analysis between electronic nose data and headspace solid phase microextraction GC-MS dataThe maximum response value of electronic nose sensor and the percentage of peak area of HS-SPME-GC-MS were tested for normality.Then the correlation analysis of Spearman correlation coefficient was used to obtain the substance basis of electronic nose response of Radix Pseudostellariae odor.Results1.The large-scale medicine market takes Chengdu lotus pond as an example.The local market mainly sells Radix Pseudostellariae in Guizhou and Fujian,occasionally in Anhui,but almost no in Shandong.The commodity grade is divided into goods selection and goods control.We visited the planting area of Xuancheng,Anhui Province,and learned about the situation of harvesting,cleaning,processing,sowing and fertilization of Radix Pseudostellariae,as well as the local production and marketing mode.2.The best conditions of electronic nose determination of Pseudostellaria were determined as follows:weighing 0.5 g,passing through No.3 sieve,heating temperature 40℃,heating time 360 s,and sample quantity 1000 μL.3.The smell of dried:and scalded samples of Radix Pseudostellariae is quite different,and there is no difference between them in different scalding time.Principal component analysis(PCA)has weak ability to distinguish Pseudostellaria from different habitats,but it is not obvious in Shandong,Anhui and Fujian.The discriminant factor analysis(DFA)has a significant effect on the identification of Radix Pseudostellariae from different places and storage periods,and the correct discriminant rate of the model established by this method can reach 100%.The results show that the maximum response value increases with the increase of storage time,which is an objective explanation for the odor aggravation of Radix Pseudostellariae after long storage.4.The conditions of HS-SPME were determined as follows:the sample quantity was 0.5 g,65.m PDMS/DVB was the extraction head,the heating temperature was 70 degrees,the desorption temperature was 240 degrees and the desorption time was 2 minutes after the extraction equilibrium for 30 minutes.5.47 batches of Radix Pseudostellariae were searched for 48 common peaks,25 of which had aroma characteristics.6.The correlation analysis between the maximum response value of electronic nose and the common peak of gas quality showed that the peak area percentage of peak 5,peak 16,peak 22,peak 25,peak 28,peak 44 and peak 47 was correlated with the electronic nose sensor.Among the related co-compounds,1-Octen-3-ol has earthy odor,while Geosmin and(E)-2-Nonenal of the other co-compounds have earthy odor,which can partially explain the source of the special smell of Pseudostellaria.ConclusionsThe results show that the special smell of Radix Pseudostellariae can be used to identify the samples from different producing areas,different producing areas and different storage periods.At the same time,this method is more effective,and provides a technical means for the quality identification of medicinal materials.In addition,the volatile components of Radix Pseudostellariae were extracted and separated by headspace solid phase microextraction gas chromatography-mass spectrometry.Combined with electronic nose technology,the specific gas of Radix Pseudostellariae was expressed scientifically and objectively,and its chemical composition was explained qualitatively.This study provides ideas and references for the objective expression of traditional Chinese medicine odor,the distinction of producing areas and processing.