Quantitative fusion omics reveals that refrigeration drives methionine degradation through perturbing 5-methyltetrahydropteroyltriglutamate-homocysteine activity. (30th May 2023)

• Record Type: Journal Article
• Authors: Jia, Wei; Wu, Xixuan; Liu, Ning; Xia, Zengrun; Shi, Lin
• Is Part Of: Food chemistry. Volume 409(2023)
• Publication Date: 2023-05-30
• Subjects: Green tea -- Refrigerated storage -- Quantitative fusion omics -- Predictive model -- UHPLC-Q-Orbitrap HRMS; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2022.135322
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Refrigeration inhibited theanine synthetase activity and decreased theanine content. Epicatechin and epigallocatechin polymerization caused browning of refrigerated tea. Achieved quantified fusion omics analysis with DCEC algorithm & similarity network. Depicted dynamic evolution of metabolites and proteins in refrigerated fresh tea. Constructed a prediction model for storage time of tea by applying four indicators. Abstract: Postharvest senescence and quality deterioration of fresh tea leaves occurred due to the limitation of processing capacity. Refrigerated storage prolongs the shelf life of fresh tea. In this study, quantitative fusion omics delineated the translational landscape of metabolites and proteins in time-series (0–12 days) refrigerated tea by UHPLC-Q-Orbitrap HRMS. Accurate quantification results showed the content of amino acids, especially l -theanine, decreased with the lengthening of the storage duration (15.57 mg g −1 to 7.65 mg g −1 ) driven by theanine synthetase. Downregulation of enzyme 5-methyltetrahydropteroyltriglutamate-homocysteine methyltransferase expression led to methionine degradation (6.29 µg g −1 to 1.78 µg g −1 ). Refrigerated storage inhibited serine carboxypeptidase-like acyltransferases activity (59.49 % reduction in 12 days) and induced the polymerization of epicatechin and epigallocatechin and generation of procyanidin dimer and δ-type dehydrodicatechin, causing the manifestation of color deterioration. A predictive model incorporating zero-order reaction and Arrhenius equation was constructed to forecast the storage time of green tea.