Study on the differential markers of Morus alba leaves before and after baked with honey based on fingerprint and chemometrics / 中国药房

ABSTRACT

OBJECTIVE To compare the changes of chemical components of Morus alba leaves， screen differential markers， and determine their contents， so as to provide reference for quality control of M. alba leaves before and after baked with honey. METHODS The fingerprints of M. alba leaves before and after baked with honey were established by high-performance liquid chromatography （HPLC）. The common peaks of the fingerprints were identified and the similarity was evaluated. The differential markers of M. alba leaves before and after baked with honey were screened by principal component analysis （PCA） and orthogonal partial least squares-discriminant analysis （OPLS-DA） using common peak are of raw material and product baked with honey of M. alba leaves as index. The quantitative analysis was carried out. RESULTS Twenty-three and twenty-four common peaks were identified from the HPLC fingerprint spectra of ten batches of raw material and ten batches of product baked with honey of M. alba leaves， respectively. The similarities of HPLC fingerprints for raw material and product baked with honey of M. alba leaves were all greater than 0.97. The results of PCA showed that raw material and product baked with honey of M. alba leaves could be divided into two categories. The results of OPLS-DA showed that the variable importance in projection of peak 2， peak H （5- hydroxymethylfurfural）， peak 1， peak 17 （isochlorogenic acid C） and peak 16 were all greater than 1. The average contents of differential marker of isochlorogenic acid C in raw material and product baked with honey of M. alba leaves were 0.093 6 and 0.127 8 mg/g， respectively； there was statistical significance （P＜0.05）. CONCLUSIONS Five differential markers such as isochlorogenic acid C are obtained. The content of isochlorogenic acid C in M. alba leaves is significantly increased after baked with honey.