Changes in curcuminoids between crude and processed turmeric based on UPLC-QTOF-MS/MS combining with multivariate statistical analysis

Abstract

• 79 curcuminoids were identified in 5 kinds of processed and crude turmeric by LC-QTOF-MS/MS. • Differences between processed and crude turmeric were investigated using multivariate statistical analysis. • Wine-processed turmeric showed the highest TPC value and the strongest DPPH free radical scavenging ability. “Pao-Zhi” was a kind of specific processed technology for traditional medicinal herbs in China. It was also a necessary technology for enhancing the efficacy, or reducing the toxicity in Traditional Chinese Medicine. For investigating the variations in curcuminoids of processed products, five processed and crude turmeric (CT) were analyzed by ultraperformance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) combining with multivariate statistical analysis. Total polyphenol contents (TPC) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of processed and crude turmeric were also investigated. As a result, a total of 79 curcuminoids (8 curcuminoids were reported in turmeric for the first time) were detected in processed and crude turmeric. Further multivariate statistical analysis results indicated that different processing technologies had influenced quality and quantity of curcuminoids in different degree. Among five processed products, wineprocessed turmeric (WT) showed a significant variation by comparison of CT. 41 curcuminoids detected in WT were significantly different to CT. Among of them, 39 curcuminoids significantly increased in relative content. In addition, WT showed the highest TPC value and the strongest DPPH free radical scavenging ability. This study could be benefit to investigate the processing mechanism of turmeric. Also, the results provided a worthy insight into the exploration of quality indicators in turmeric during the “Pao-Zhi” process.