Multiomics strategy reveals the accumulation and biosynthesis of bitter components in Zanthoxylum schinifolium Sieb. et Zucc

The perceptible bitterness of Zanthoxylum schinifolium Sieb. et Zucc is an important factor limiting its consumption. Metabolomics was used to identify potentially bitter metabolites during the development of Z. schinifolium, and dynamic changes in 17 key bitter components were characterized. The key bitter components in Z. schinifolium at different developmental stages were mainly synthesized through the “phenylpropanoid biosynthesis”, “flavonoid biosynthesis”, and “flavone and flavonol biosynthesis” pathways. In combination with transcriptomic data, the expression of related genes regulates the accumulation process of these bitter components; based on this, a biosynthetic pathway of bitter components in Z. schinifolium was constructed. In addition, quercetin-3-galactoside, isoquercitin, quercitrin, kaempferol, and isorhamnetin were identified as the main sources of bitterness in mature Z. schinifolium based on an evaluation of taste activity value. These findings provide valuable information for understanding mechanisms underlying Z. schinifolium bitterness and promoting the further development of high-quality Z. schinifolium.