Quality consistency evaluation of Isatidis Folium combined with equal weight quantified ratio fingerprint method and determination of antioxidant activity.

Isatidis Folium has been known as a valuable traditional Chinese medicine for thousands of years. Little attention, however, has been paid to its quality control. The aim of the present study was to establish a novel strategy to monitor and assess the quality consistency of Isatidis Folium. First, 20 samples were separated and identified simultaneously by high-performance liquid chromatography in an effective, quick and sensitive way. Then, Single-wavelength fingerprint was fused into multi-wavelength fingerprints to show fingerprints' information thoroughly. The similarity analyses of fingerprints were performed by equal weight quantified ration fingerprint method in terms of qualitative and quantitative aspects. The evaluation result showed that 20 batches of samples were classified into different grades. In addition, the relationship between fingerprints and antioxidant activity were investigated by partial least-squares model, which offered significant medicinal efficacy information for quality control. This comprehensive strategy provided a valuable reference for Isatidis Folium to ameliorate their quality control.