Department of Botany, Division of Pharmacognosy, University of Debrecen, Egyetem tér 1, 4032 Debrecen, Hungary.
Department of Botany, Division of Pharmacognosy, University of Debrecen, Egyetem tér 1, 4032 Debrecen, Hungary; Healthcare Industry Institute, University of Debrecen, 4032 Debrecen, Hungary.
Food Res Int. 2023 Feb;164:112347. doi: 10.1016/j.foodres.2022.112347. Epub 2022 Dec 26.
Fenugreek (Trigonella foenum-graecum L.) is an important food and spice with bioactive compounds against diabetes. In this study, fenugreek seeds germinating in darkness for 72 h were studied using quantification of trigonelline and 4-hydroxyisoleucine and an LC-ESI-MS/MS-based metabolomic approach capable of accurately estimating 237 features from various primary and specialized compound classes. During germination, the concentrations of trigonelline and 4-hydroxyisoleucine rose by 33.5% and 33.3%, respectively. At the same time, untargeted metabolomics revealed 9 putative flavonoids increasing 1.19- to 2.77-fold compared to the dormant seeds. A set of 19 steroid saponins rose by 1.08- to 31.86-fold. Primary metabolites however showed much more variability: abundance changes in amino acid derivatives, peptides and saccharides fell in the 0.09- to 22.25-fold, 0.93- to 478.79-fold and 0.36- to 941.58-fold ranges, respectively. To increase biosynthesis of specialized metabolites during germination, sprouts were exposed to 1-100 mM methyl jasmonate (MeJA) and methyl salicylate (MeSA). The hormone treatments affected normal metabolism: 67.1-83.1 % and 64.1-83.5 % of compounds showed a reduction compared to the controls in 100 mM MeJA and MeSA treatments at different sampling time points. Contrary to expectations, the abundance of flavonoids decreased, compared to the control sprouts (0.75- and 0.68-fold change medians, respectively). The same was observed for most, but not all steroid saponins. The quality-controlled untargeted metabolomics approach proved to yield excellent insight into the metabolic changes during germination of fenugreek. The results suggest that although fenugreek germination causes major shifts in plant metabolism, there are no major qualitative changes in bioactive specialized metabolites during the first three days. This stability likely translates into good bioactivity that is similar to that of the seeds. Because the large changes in the primary metabolites likely alter the nutritive value of the seed, further studies are warranted.
葫芦巴（Trigonella foenum-graecum L.）是一种重要的食品和香料，具有抗糖尿病的生物活性化合物。在这项研究中，研究了在黑暗中发芽 72 小时的葫芦巴种子，使用了瓜氨酸和 4-羟基异亮氨酸的定量测定以及基于 LC-ESI-MS/MS 的代谢组学方法，该方法能够准确估计来自各种初级和特殊化合物类别的 237 种特征。在发芽过程中，瓜氨酸和 4-羟基异亮氨酸的浓度分别增加了 33.5%和 33.3%。与此同时，非靶向代谢组学揭示了 9 种可能的类黄酮，与休眠种子相比增加了 1.19 至 2.77 倍。一组 19 种甾体皂甙增加了 1.08 至 31.86 倍。然而，初级代谢物的变化更大：氨基酸衍生物、肽和糖的丰度变化分别在 0.09 至 22.25 倍、0.93 至 478.79 倍和 0.36 至 941.58 倍范围内。为了在发芽过程中增加特殊代谢物的生物合成，芽苗被暴露于 1-100mM 茉莉酸甲酯（MeJA）和水杨酸甲酯（MeSA）下。激素处理会影响正常的新陈代谢：与对照组相比，在 100mM MeJA 和 MeSA 处理的不同采样时间点，67.1-83.1%和 64.1-83.5%的化合物减少。与预期相反，与对照芽苗相比，类黄酮的丰度降低（中位数分别为 0.75 倍和 0.68 倍变化）。大多数甾体皂甙也是如此，但并非全部。经过质量控制的非靶向代谢组学方法证明可以很好地了解葫芦巴发芽过程中的代谢变化。结果表明，尽管葫芦巴发芽导致植物代谢发生重大变化，但在头三天内，生物活性特殊代谢物没有发生重大的定性变化。这种稳定性很可能转化为与种子相似的良好生物活性。由于初级代谢物的巨大变化可能会改变种子的营养价值，因此需要进一步的研究。
