Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China.
Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China; University of the Chinese Academy of Sciences, Beijing, 100049, China.
Plant Physiol Biochem. 2022 Nov 1;190:24-34. doi: 10.1016/j.plaphy.2022.08.026. Epub 2022 Sep 3.
Dendrobium officinale, which is a medicine food homology plant, contains many metabolites, especially polysaccharides and flavonoids. Unlike flowers and stems, which are the most frequently harvested organs for a variety of uses, leaves tend to be discarded. This study assessed main metabolites in leaves to identify the most appropriate timing of collection during harvest, which was divided into three stages (S1-S3: 8, 10, and 11 months after sprouting, respectively). Metabolomic and transcriptomic analyses of S1-S3 were performed. Water-soluble polysaccharides (WSPs), flavonoids and free amino acids (FAAs) were detected in leaves. WSPs decreased from S1 to S3 but flavonoids and some FAAs (e.g., phophoserine) increased from S1 to S2, then decreased from S2 to S3. In all three stages, mannose was the dominant monosaccharide among WSPs, followed by glucose. In S2, 35 flavonoids were identified, the most abundant being rutin, schaftoside and vitexin, while 34 FAAs were identified in all three stages, the most abundant being tyrosine, phosphoserine and alanine. A total of 2584, 3414 and 2032 differentially expressed genes (DEGs) were discovered in S1 vs S2, S1 vs S3 and S1 vs S3, respectively. Correlation analysis revealed that five DEGs (DoSUS, DoXYLA, DoFRK, DoGMP, and DoCSLA), two DEGs (DoDFR, and DoANS) and a single DEG (DoPGAM) were involved in the metabolism of WSPs, flavonoids and phosphoserine, respectively. The findings of this study lay a foundation for the commercial exploitation of metabolites in the harvested leaves of D. officinale, and the use of detected DEGs in applied genetic studies.
铁皮石斛，一种药食同源植物，含有多种代谢物，尤其是多糖和类黄酮。与花朵和茎干不同，它们是各种用途中最常被收获的器官，而叶子往往被丢弃。本研究评估了叶子中的主要代谢物，以确定在收获期间最适宜的采集时间，收获期分为三个阶段（S1-S3：分别为发芽后 8、10 和 11 个月）。对 S1-S3 进行代谢组学和转录组学分析。检测到叶子中的水溶性多糖（WSPs）、类黄酮和游离氨基酸（FAAs）。WSPs 从 S1 到 S3 减少，但类黄酮和一些 FAAs（如磷酸丝氨酸）从 S1 到 S2 增加，然后从 S2 到 S3 减少。在所有三个阶段，甘露糖都是 WSPs 中的主要单糖，其次是葡萄糖。在 S2 中，鉴定出 35 种类黄酮，最丰富的是芦丁、山奈苷和荭草苷，而在所有三个阶段中鉴定出 34 种 FAAs，最丰富的是酪氨酸、磷酸丝氨酸和丙氨酸。在 S1 与 S2、S1 与 S3 和 S1 与 S3 之间分别发现了 2584、3414 和 2032 个差异表达基因（DEGs）。相关性分析表明，五个 DEGs（DoSUS、DoXYLA、DoFRK、DoGMP 和 DoCSLA）、两个 DEGs（DoDFR 和 DoANS）和一个单个 DEG（DoPGAM）分别参与了 WSPs、类黄酮和磷酸丝氨酸的代谢。本研究的结果为铁皮石斛收获叶片中代谢物的商业开发以及检测到的 DEGs 在应用遗传研究中的应用奠定了基础。
