An effective UPLC method for the quantification and fingerprint analysis of amides in a South China native medicinal herb, abri herba

Abstract

Abri herba originates from Abrus mollis and Abrus cantoniensis. Its leaves are rich in amides and they are often used as folk food ingredients and tea in China. However, the effective analysis methods for amides have not been reported. An UPLC method was developed to obtain the fingerprint profiles and to quantify these amides. Twenty common peaks were identified and analyzed by similarity, hierarchical clustering, and principal component analysis of UPLC fingerprints from 24 samples. Furthermore, four amides were simultaneously quantitated by Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and Heat Map. The similarity of the fingerprints ranged from 0.734 to 0.989. The contents of amides were affected by the origins of the samples, and the closer the origin, the higher similarity of amide profiles. (E)-N-(4-hydroxycinnamoyl) tyrosine was the major compound ranging from 0.75 to 6.36 mg g−1, followed by abrusamide A (0.44 ∼ 1.14 mg g−1), abrusamide B (0.35 ∼ 0.75 mg g−1), and abrusamide C (0.05 ∼ 0.25 mg g−1). This is the first report to fingerprints and quantification analytical method of amides in leaves of abri herba.