基于GC-IMS和化学计量学分析不同颜色永顺莓茶挥发性有机物差异OA

Objective To explore the differences in volatile organic compounds(VOCs)among different-colored Yongshun vine tea and provide a theoretical basis for its development and utilization.Methods Gas chromatography-ion mobility spectrometry(GC-IMS)was employed to check the VOCs in purple and green Yongshun vine tea.Identification was performed by combining the gas chromatography retention index database(NIST 2020)with the IMS migration time database.The VOCal 04.03 data processing software was used to generate characteristic fingerprints for analyzing differential components.Principal component analysis(PCA),"nearest-neighbor"fingerprint analysis,and orthogonal partial least squares discriminant analysis(OPLS-DA)were conducted on the peak volumes of VOCs checked by GC-IMS.Characteristic markers distinguishing the different-colored Yongshun vine tea were screened by using variable importance in projection(VIP)values＞1 and cluster analysis(CA).Results A total of 115 VOC peaks were checked in two different-colored Yongshun vine tea samples,among which 91 VOCs were identified,including 25 aldehydes,16 ketones,15 alcohols,11 esters,5 terpenoids,5 pyrazines,5 furans,5 carboxylic acids,and 4 other types of components.GC-IMS fingerprints showed that the types of VOCs in the two samples were relatively consistent,while the differences were mainly reflected in relative contents.PCA,"nearest-neighbor"fingerprint analysis,and OPLS-DA models could clearly distinguish the two types of Yongshun vine tea.A total of 21 VOCs were screened as characteristic markers based on VIP＞1 and CA.Conclusion Significant differences in VOCs were observed between the two different-colored Yongshun vine tea samples.The screened characteristic VOCs can provide a scientific reference for further studies on their pharmacological,material basis,and comprehensive resource development and utilization.