Integrated metabolic phenotypes and gene expression profiles reveal enzymatic browning mechanism in postharvest chrysanthemum

• Published in: Industrial crops and products 2024-05, Vol.211, p.118286, Article 118286
• Main Authors: Yang, Dan, Liu, Shanshan, Zhu, Yuyun, Feng, Weihong, Chen, Sha, Zhang, Yongxin, Wang, Wei, Zhang, Mei, Kang, Chen, Cai, Zhongqi, Wei, Shouhui, Zhu, Jingjing
• Format: Article
• Language: English
• Subjects: Browning product; Chrysanthemum morifolium; Enzymatic browning; Metabolomics; Molecular mechanism; Transcriptomics
• ISSN: 0926-6690; 1872-633X
• DOI: 10.1016/j.indcrop.2024.118286

Chrysanthemum (Chrysanthemum morifolium Ramat) is a valuable crop mainly used for medicine, beverages and ornament. Enzymatic browning causes serious postharvest flower deterioration of chrysanthemum, but the mechanism remains unclear. To clarify the mechanism involved, the cellular ultrastructure, metabolites, browning products, and differentially expressed genes of chrysanthemum were studied systematically. During the browning process, cellular compartmentalization was severely disrupted and the contents of chlorogenic acid derivatives and flavonoid glycosides decreased significantly. A browning product with a dihydrobenzofuran skeleton was purified and identified for the first time from a simulated browning reaction of chlorogenic acid catalyzed by peroxidase. Moreover, six differentially expressed genes were for the first time identified to be involved in the regulation of oxidase by transcriptome and qPCR, and one of which (c76073_g1) was validated using in vitro enzyme activity determination. This research elucidates the inherent mechanism of enzymatic browning, provides a scientific explanation for the steam-treated processing of chrysanthemums and lays the foundation for the molecular breeding of anti-browning chrysanthemum varieties. [Display omitted] •Metabolites, enzymes, cellular structure, and related genes had significant changes.•Cell Compartmentalization of browning chrysanthemum was obviously disrupted.•Chlorogenic acid derivatives was main substrate during chrysanthemum browning.•One newly browning product was elucidated as a chlorogenic acid dimer.•One differentially expressed gene was validated to regulate related oxidase.