Application Of Phenolic Acid Fingerprinting Combined With Principal Component Analysis In Characterizing Different Tomatoes

Tomato is one of the most important vegetables worldwide.China contributes most to the production of tomato.During 2001 to 2013,the tomato production of both the world and China grew steadily.Tomato has a high nutritional value and has been widely studied for its lycopene.Besides lycopene,phenolic compounds are also the main antioxidant substances of tomatoes.In this study,the phenolic acids fingerprinting analysis method of tomatoes was successfully established.The polyphenols in 6 kinds of tomato samples(organically grown cherry tomatoes,conventionally grown cherry tomatoes,organically grown big tomatoes,conventionally grown big tomatoes,cherry tomatoes,big tomatoes)were extracted using 80% ethanol.Then,the extracts were subjected to ultraperformance liquid chromatography-ultraviolet detection(UPLC-UV)and 16 main peaks were detected by UPLC-UV.In the study,the phenolic acids fingerprintings of all tomato samples were similar.Then,the chemical component of corresponding peaks were identified by ultraperformance liquid chromatography-mass spectrometry(UPLC-MS),combined with the phenolic acids fingerprinting of tomatoes,it could be indicated chlorogenic acid and rutin were the two main polyphenols of tomatoes.Next,the phenolic acids fingerprinting of tomatoes acquired by UPLC-UV combined with principal component analysis analysis were applied in differentiating 6 kinds of tomato samples.Our results indicated that the phenolic acids fingerprinting of UPLC-UV combined with principal component analysis were able to differentiate(1)organically grown cherry tomatoes from conventionally grown cherry tomatoes,(2)organically grown big tomatoes from conventionally grown big tomatoes,(3)cherry tomatoes from big tomatoes.This study will provide scientific evidences and theoretical foundation for the quality assurance of organic tomatoes,organic tomato products and cherry tomato products.