Characterization of extractable components of fresh and fermented Huarong large-leaf mustard and their inhibitory effects on human colon cancer cells

Abstract

Leaf mustard is a popular cruciferous vegetable, and its chemical composition and biological activities have seldom been investigated. The aim of this study was to characterize the primary extractable components of fresh and fermented leaf mustard and determine their growth inhibitory effects on human colon cancer cells. Our results show that the contents of total soluble sugar, fat, protein, and glucosinolates in the extract of fresh leaf mustard (EFrLM) were significantly higher than those in the extract of fermented leaf mustard (EFeLM), while the inverse was true for amino nitrogen and total polyphenol contents. A total of 45 compounds and 72 volatile components were further identified in the two extracts by LC-MS and GC-MS, respectively. EFrLM and EFeLM displayed no inhibitory effects on normal human colon myofibroblast CCD-18Co cells, but both induced cell cycle arrest and extensive cellular apoptosis in HCT116 cells. Cell cycle-related genes and signaling proteins (cyclin B, cyclin D1, and cyclin E) were downregulated, and apoptosis-related genes and signaling proteins (caspase-3 and cleaved caspase-3) were upregulated. Notably, EFeLM exhibited a stronger inhibitory effect than EFrLM on HCT116 cells. The results of this study lay a solid foundation for understanding the chemical constituents and biological activities of leaf mustard and highlight its anticancer potential.