Figure 2.

Chromatogram of polygonum cuspidatum extract under the wavelength of 280 nm: 1. p‐coumaric acid (25.6 min); 2. ellagic acid (27.7 min); 3. piceid (34 min); 4. coumarin (41 min); 5. emodin (41.5 min); 6. cinnamic acid (52 min)