Metabolomics-based study on the changes of endogenous metabolites during adventitious bud formation from leaf margin of Bryophyllum pinnatum (Lam.) Oken.

Bryophyllum pinnatum (Lam.) Oken is an ornamental and ethno-medicine plant, which can grow a circle of adventitious bud around the leaf margin. The dynamic change of metabolites during the development of B. pinnatum remains poorly understood. Here, leaves from B. pinnatum at four developmental stages were sampled based on morphological characteristics. A non-targeted metabolomics approach was used to evaluate the changes of endogenous metabolites during adventitious bud formation in B. pinnatum. The results showed that differential metabolites were mainly enriched in sphingolipid metabolism, flavone and flavonol biosynthesis, phenylalanine metabolism, and tricarboxylic acid cycle pathway. The metabolites assigned to amino acids, flavonoids, sphingolipids, and the plant hormone jasmonic acid decreased from period Ⅰ to Ⅱ, and then increased from period Ⅲ to Ⅳ with the emergence of adventitious bud (period Ⅲ). While the metabolites related to the tricarboxylic acid cycle showed a trend of first increasing and then decreasing during the four observation periods. Depending on the metabolite changes, leaves may provide conditions similar to in vitro culture for adventitious bud to occur, thus enabling adventitious bud to grow at the leaf edge. Our results provide a basis for illustrating the regulatory mechanisms of adventitious bud in B. pinnatum.

UPLC-MS-Based Non-targeted Analysis of Endogenous Metabolite Changes in the Leaves of Scabiosa tschiliensis Grüning Induced by 6-Benzylaminopurine and Kinetin.

In vitro propagation technology with plant growth regulators (PGRs) is generally applied in the cultivation of Scabiosa tschiliensis, which can solve collection difficulties and limited resources of S. tschiliensis. Nevertheless, comprehensive metabolomic evaluation on S. tschiliensis with PGR effects is still lacking. In this work, a non-targeted metabolomics approach, coupled with statistical and pathway enrichment analysis, was used to assess the regulatory influences of 6-benzylaminopurine (6-BA) and kinetin (KT) applied in S. tschiliensis. The results showed that the PGRs affect metabolism differentially, and the addition of 6-BA and KT can increase different secondary metabolites. In the two PGR groups, some primary metabolites such as L-phenylalanine, L-tyrosine, L-arginine, L-asparagine, and D-proline were significantly reduced. We suspect that under the action of PGRs, these decreased amino acids are derived into secondary metabolites such as umbelliferone, chlorogenic acid, and glutathione. Additionally, some of those secondary metabolites have a biological activity and can also promote the plant growth. Our results provide a basis for the targeted cultivation and utilization of S. tschiliensis, especially the expression of metabolites related to PGR application.