Studies On The Quality Evaluation Of Scutellaria Extract

Objective: The study is to establish the relationship between HPLC fingerprints of the Scutellaria extract and the inhibition rate of Staphylococcus aureus in vitro, determine the antibacterial active ingredients, and a measurement to test the content of 5 kinds of flavonoids in Scutellaria extract, in order to improve the quality evaluation of Scutellaria extract.Methods: On the based objective of the present study, the relevant literatures of Scutellaria extract were collected. The origin, ingredients, pharmacological effects and quality evaluation methods were summarized. HPLC fingerprint was established after the preparation of Scutellaria extract and the common peaks were selected based on the fingerprint; the inhibition rate of Scutellaria extract(as the pharmacodynamic evaluation index) on Staphylococcus aureus was determined in vitro. Gray relational analysis method(GRA) was used to analysis the relationship between the HPLC fingerprint data and the inhibition rate. Then a multi-assessment method to measure the quality evaluation of Scutellaria extract was set up. In order to establish a new method of quality evaluation and validate its feasibilities by the simultaneous quantitative assay in Scutellaria extract, the quantitative analysis of multi-components by single marker(QAMS) was established and validated. We used Baicalin, Baicalein, Wogonoside, Wogonin, Oroxylin-A as analysts to evaluate the quality. Then 20 batches of Scutellaria extract were determined by both external standard method and QAMS.Results: The HPLC fingerprint was established through methodological study, then 20 batches Scutellaria extract were tested and eight common peaks were selected based on the fingerprints. The suitable concentration of Scutellaria extract was 156.25 μg·m L-1, the concentration of Staphylococcus aureus was 105~106 cfu ? m L-1, and then the inhibition rates were measured. The data of 20 batches of samples were analyzed by GRA, finding 8 ingredients positively correlated with the inhibition rate and the order in descend as follow: ingredients 2(Baicalin) > ingredients 6(Baicalein) > ingredients 4 > ingredients 8(Oroxylin-A) > ingredients 3 > ingredients 7(Wogonin) > ingredients 1 > ingredients 5(Wogonoside). In addition, we measured using a QAMS and external standard method for the determination of five flavonoids in 20 bathes Scutellaria extract. The results showed no significant difference between the two methods.Conclusion: The application of Grey Relational Analysis was to analyze the components related to antimicrobial effect and the QAMS was used for determination of flavonoids in Scutellaria extract to further improve the quality evaluation of Scutellaria extract and provide reference for improving the quality standard of Scutellaria extract.