Fig. 1

Identification of chemical compounds in SF by HPLC-Q-TOF-MS and quality control of SF. a Representative base peak intensity chromatogram of SF based on HPLC-Q-TOF-MS in positive mode. b HPLC chromatograms of calycosin and protocatechuic acid at 260 nm. c HPLC chromatogram of SF at 260 nm