Rapid screening and separating two radical scavengers in Lycium barbarum L. by DPPH-HPLC analysis-combined dual-mode high-speed countercurrent chromatography

ABSTRACT

A target-guidance separation strategy composed of activity screening process with high-performance liquid chromatography and separating process with high-speed countercurrent chromatography (HSCCC) has been developed and used to screen and separate radical scavengers from Lycium barbarum extract. Two compounds were found to be radical scavengers and dual-mode HSCCC was used to separate these two defined compounds due to the big gap in polarity between them. Rutin and quercetin were separated with purities of 96.5% and 95.0%. Their structures were identified by nuclear magnetic resonance and both of them exhibit potent radical scavenging activity with the IC₅₀ values being 20.07 ± 0.10 and 3.11 ± 0.03 μg/mL, respectively.

KEYWORDS:

• Radical scavenger
• Lycium barbarum L.
• high-speed countercurrent chromatography
• dual-mode elution

Additional information

Funding

Authors gratefully acknowledge the financial support by the National Science and Technology Major Project: [grant number 2018ZX09711001-001-002], the Key Research and Development Program of Gansu Province: [grant number 18YF1FA126], and Goji Berry Technological Cooperation Project in Comprehensive Agricultural Development of Ningxia Autonomous Region: [grant number NTKJ2017-01-06]. Dr Xin-Yi Huang is also grateful to the financial support from Youth Innovation Promotion Association (CAS number 2016369).