环境紫外线B信号通过类黄酮生物合成中的代谢通量的变化来调节茶的风味特征

Ambient Ultraviolet B Signal Modulates Tea Flavor Characteristics via Shifting a Metabolic Flux in Flavonoid Biosynthesis

第一作者

Ning Lin

第一单位

安农大

通讯作者

Linlin Liu

Abstract

背景+问题：Tea leaves contain an extraordinarily high level of flavonoids that contribute to tea health benefits and flavor characteristics, but the regulatory mechanism of ambient ultraviolet B (UV-B) on tea flavonoid enrichment remains unclear.

主要研究：Here, we report that ambient UV-B modulates tea quality by inducing a metabolic flux in flavonoid biosynthesis.

结果1：UV-B absencedecreased bitter- and astringent-tasting flavonol glycosides (kaempferol-7-O-glucoside, myricetin-3-O-glucoside, and quercetin-7-O-glucoside) but increased non-galloylated catechins. Conversely, supplementary UV-Bincreased flavonols and decreased catechins in tea leaves.

结果2： These responses were achieved via CsHY5, which mediates the UV-B-induced MYB12 activation and binds to the promoters of flavonoid biosynthetic genes (CsFLS, CsLARa, and CsDFRa), leading to flavonoid changes.

结果3： Transcriptomic data indicated that UV-B-induced tea flavonoid regulation is responsive to multiple biotic and abiotic environmental stresses.

结论：These findings improve our understanding of light-regulated tea astringency and bitterness underlying shading effects and seasonal light changes and provide novel insights into tea cultivation management and processing.

摘  要

茶叶中的类黄酮含量极高，有助于茶的健康和风味特性，但环境紫外线B（UV-B）对茶类黄酮富集的调节机制仍不清楚。在这里，我们报告说，环境UV-B通过诱导类黄酮生物合成中的代谢通量来调节茶的质量。缺少UV-B会减少苦味和涩味的黄酮糖苷（山奈酚7-O-葡萄糖苷，杨梅素-3-O-葡萄糖苷和槲皮素-7-O-葡萄糖苷），但增加了非半乳糖化的儿茶素。相反，补充UV-B可增加茶叶中的黄酮醇含量和降低儿茶素含量。这些反应是通过CsHY5实现的，CsHY5介导UV-B诱导的MYB12活化并与类黄酮生物合成基因（CsFLS，CsLARa和CsDFRa）的启动子结合，从而导致类黄酮变化。转录组数据表明，UV-B诱导的茶类黄酮调节对多种生物和非生物环境胁迫有响应。这些发现提高了我们对调光茶的涩味和阴影作用和季节性光照变化的苦味的理解，并为茶的栽培管理和加工提供了新颖的见解。

DOI: https://doi.org/10.1021/acs.jafc.0c07009

Journal: Journal of Agricultural and Food Chemistry

Impact Factor：4.192

Published date: March 15, 2021

END

三月

16

科学技术史上的今天

1926年3月16日，美国科学家罗伯特·戈达德在马萨诸塞州的奥巴恩发射了世界上第一枚液体燃料火箭。火箭长3.04米，用汽油和液态氧混合作为燃料，飞行2.5秒，达12米高，56米远。虽然这些数字在现在看来并不惊人，但却具有划时代的意义。

1978年3月16日，利比里亚油轮“阿莫科·卡迪兹号”在英国波特赛尔搁浅，船上22万吨原油倾流大海，污染海滩160余公里。

Where there is a will, there is a way!