Comparative study on main components and antioxidant activity of Scutellaria Radix from different genuine producing areas
This study aims to explore the flavonoid characteristic fingerprint and antioxidant capacity spectrum-effect relation-ship of Scutellaria Radix in Laiwu,Shandong Province and Chengde,Hebei Province.On the basis of constructing ultra-high performance liquid chromatography(UPLC)fingerprint profiles of Scutellaria Radix,this study employed an in vitro antioxi-dant assay to evaluate the scavenging ability of 25 batches of Scutellaria Radix from different authentic production areas on DPPH,ABTS and O2-free radicals,and their half maximal inhibitory concentration(IC50)values were determined.Orthogonal partial least-squares discriminant analysis(OPLS-DA)method and bivariate correlation analysis were employed to establish the spectrum-efficacy relationship between the chemical composition and antioxidant activity.The fingerprint similarity of 25 batches samples exceeded 0.983,in which 16 common peaks were identified.Twelve compounds were identified by ultra-per-formance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS)technology.The Scutellaria Radix from the two areas had strong scavenging abilities of DPPH,ABTS and O2-free radicals,and the antioxidant capacity of Scutellaria Radix from Laiwu,Shandong province was superior to that from Chengde,Hebei Province.The two OPLS-DA mod-els can successfully distinguish Scutellaria Radix from two genuine producing areas.Baicalin,baicalein and oroxylin A-7-O-β-D-glucuronide were differential markers in them.The spectrum-efficacy analysis revealed that flavonoids in Scutellaria Radix may increase the scavenging abilities of DPPH,ABTS and O2-free radicals based on their synergistic effects.This study estab-lished the spectrum-efficacy evaluation model combined chemical composition with antioxidant activity of Scutellaria Radix.It can be used to evaluate the quality of Scutellaria Radix from different genuine producing areas,and can provide help for the reseach of the geotropism of Chinese medicinal materials.