Characterization and discrimination of chilli peppers based on multi-element and non-targeted metabolomics analysis

Abstract

The present study aimed at comparative analysis of multi-element and metabolomic profiles between two varieties of chilli peppers. A total of 53 macro-, micro-, trace and toxic elements were simultaneously quantified using inductively coupled plasma mass spectrometry, and 24 of them varied significantly between Jize (n = 3) and Korean (n = 3) chilli peppers. In addition, an UHPLC-Q-TOF/MS-based untargeted metabolomics coupled with chemometrics approach was performed to identify potential compounds for the discrimination of Jize (n = 8) and Korean (n = 8) chilli peppers. A panel of 119 metabolites were screened out from the 220 annotated compounds, with the criteria of p ≤ 0.05, fold changes either ≥ +2 or ≤ −2 and variable importance in projection scores from the PLS-DA models ≥1. Moreover, flavonoids and capsaicinoids were the most important differential compounds between Jize and Korean chilli peppers. Our results demonstrate that Jize and Korean chilli peppers could be clearly distinguished based on their multi-element and metabolite profiles. Results may help to further unravel the candidate bioactive components for the health-promoting effects of chilli peppers.