The aerial parts of Salvia miltiorrhiza Bunge, as the non-medicinal parts, are always discarded during harvesting, resulting in a huge waste of resources and environmental pressure. Due to the high flavonoid content and their antioxidant activities characteristics, the aerial parts of S. miltiorrhiza can be developed into natural antioxidants and used in foods. A high-speed counter-current chromatography (HSCCC) method, using a two-phase solvent system composed of tert-butyl methyl ether/n-butanol/acetonitrile/water (3:1:1:20, v/v), was the first to successfully isolate five flavonoids from the aerial parts of S. miltiorrhiza in one attempt, and separately categorized as rutin (1), isoquercitrin (2), kaempferol-3-O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside (3), kaempferol-3-O-β-d-glucopyranoside (4) and apigenin-7-O-β-d-glucopyranoside (5) after identification. The purities of these plant isolates were 97.3%, 99.5%, 92.8%, 98.1% and 98.7%, respectively. All the flavonoids were identified by HR-ESI-MS, 1D and 2D NMR. Compounds 3 and 5 were firstly isolated from the plant of S. miltiorrhiza. Results from antioxidant assays showed that rutin (1) and isoquercitrin (2) had higher antioxidant capacities compared to L-ascorbic acid as the positive control.

Background: Salvia miltiorrhiza, a well-known traditional Chinese medicine, frequently suffers from replant diseases that adversely affect its quality and yield. To elucidateS. miltiorrhiza’s metabolic adaptations to replant disease, we analyzed its metabolome and transcriptome, comparing normal and replant diseased plants for the first time.Results: We identified 1,269 metabolites, 257 of which were differentially accumulated metabolites, and identified 217 differentially expressed genes. Integrated transcriptomic and metabolomic analyses revealed a significant up-regulation and co-expression of metabolites and genes associated with plant hormone signal transduction and flavonoid biosynthesis pathways in replant diseases. Within plant hormone signal transduction pathway, plants afflicted with replant disease markedly accumulated indole-3-acetic acid and abscisic acid, correlating with high expression of their biosynthesis-related genes (SmAmidase,SmALDH,SmNCED, andSmAAOX3). Simultaneously, changes in hormone concentrations activated plant hormone signal transduction pathways. Moreover, under replant disease, metabolites in the local flavonoid metabolite biosynthetic pathway were significantly accumulated, consistent with the up-regulated gene (SmHTC1andSmHTC2). The qRT-PCR analysis largely aligned with the transcriptomic results, confirming the trends in gene expression. Moreover, we identified 10 transcription factors co-expressed with differentially accumulated metabolites.Conclusions: Overall, we revealed the key genes and metabolites ofS. miltiorrhizaunder replant disease, establishing a robust foundation for future inquiries into the molecular responses to combat replant stress.

Five flavonoids, quercetin-3-O-β-D-apiofuranosyl-(1→2)-β-D-galactoside, hyperoside, kaempferol-3-O-β-D-glucoside, kaempferol, quercetin, and chlorogenic acid, have been isolated and purified for the first time from the seeds of Cuscuta chinensis Lam. By high-speed countercurrent chromatography (HSCCC). Ethyl acetate extract (700 mg) was separated by HSCCC using solvent system [ethyl acetate–ethanol–water–acetic acid (4:1:5:0.2, v/v)], yielding 34 mg of quercetin-3-O-β-D-apiofuranosyl-(1→2)-β-D-galactoside, 27.5 mg of chlorogenic acid, 86 mg of hyperoside, and 12 mg of kaempferol-3-O-β-D-glucoside. Then we collected tail blowing fluid and evaporated to dryness, obtaining 196 mg of extract. Afterwards 196 mg of extract used solvent system [chloroform–methanol–water (4:3:2, v/v)] by HSCCC, gaining 53 mg of kaempferol and 18 mg of quercetin. The purities of six components reach over 95%. The chemical structures of these compounds were identified by electrospray ionization mass spectrometry (ESI-MS), ¹H-NMR, and ¹³C-NMR.