Development of Quality Standards for Erythrina Variegata L. Bark Formula Granules Based on Consistency of Standard Decoction

OBJECTIVE  To establish a quality standard for Erythrina variegata L. bark formula granules guided by the consistency of its standard decoction.

METHODS  The quality standard was developed based on the extraction yield, total content of chlorogenic acid, cryptochlorogenic acid, and neochlorogenic acid, and characteristic chromatographic profile of the standard decoction. Similarity evaluation and chemical pattern recognition were performed on three batches of formula granules and 15 batches of standard decoctions.

RESULTS  The average extraction yield of 15 batches of Erythrina variegata L. bark standard decoctions was 9.7%. The characteristic chromatogram contained 8 characteristic peaks. The total content of chlorogenic acid, cryptochlorogenic acid, and neochlorogenic acid averaged 140.5 mg·g⁻¹. For formula granules, the extraction yield was controlled within 7.0%–12.6%, and the total content of the three chlorogenic acids was limited to 68.5–127.4 mg·g⁻¹. The similarity between the characteristic chromatograms of formula granules and the reference standard decoction exceeded 0.95. Principal component analysis(PCA), partial partial least squares discrimination analysis, and heatmap cluster analysis effectively distinguished standard decoctions from different geographical origins, while formula granules clustered closely with their corresponding standard decoctions.

CONCLUSION  This study provides a reference framework for establishing quality standards and controlling the consistency of Erythrina variegata L. bark formula granules.