Separation of Five Flavonoids from Aerial Parts of <i>Salvia Miltiorrhiza</i> Bunge Using HSCCC and Their Antioxidant Activities

• Main Authors: Fan Yang, Yingxue Qi, Wei Liu, Jia Li, Daijie Wang, Lei Fang, Yongqing Zhang
• Format: Article
• Language: English
• Published: MDPI AG 2019-09-01
• Series: Molecules
• Subjects: aerial parts of <i>Salvia miltiorrhiza</i> Bunge; HSCCC; flavonoids; antioxidant activities
• Online Access: https://www.mdpi.com/1420-3049/24/19/3448

The aerial parts of <i>Salvia miltiorrhiza</i> 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 <i>S. miltiorrhiza</i> 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 <i>tert</i>-butyl methyl ether/<i>n</i>-butanol/acetonitrile/water (3:1:1:20, <i>v</i>/<i>v</i>), was the first to successfully isolate five flavonoids from the aerial parts of <i>S. miltiorrhiza</i> in one attempt, and separately categorized as rutin (<b>1</b>), isoquercitrin (<b>2</b>), kaempferol-3-<i>O</i>-&#945;-<span style="font-variant: small-caps;">l</span>-rhamnopyranosyl-(1&#8594;6)-&#946;-<span style="font-variant: small-caps;">d</span>-glucopyranoside (<b>3</b>), kaempferol-3-<i>O</i>-&#946;-<span style="font-variant: small-caps;">d</span>-glucopyranoside (<b>4</b>) and apigenin-7-<i>O</i>-&#946;-<span style="font-variant: small-caps;">d</span>-glucopyranoside (<b>5</b>) 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 <b>3</b> and <b>5</b> were firstly isolated from the plant of <i>S. miltiorrhiza.</i> Results from antioxidant assays showed that rutin (<b>1</b>) and isoquercitrin (<b>2</b>) had higher antioxidant capacities compared to L-ascorbic acid as the positive control.