Processing Technology Investigation of Loquat (Eriobotrya japonica) Leaf by Ultra-Performance Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry Combined with Chemometrics

Labin Wu,Xue Jiang,Linfang Huang,Shilin Chen,Jacob Guy Bundy

doi:10.1371/journal.pone.0064178

Abstract

Ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS) and multivariate statistical analysis were used to investigate the processing technology of Loquat (Eriobotrya japonica) leaf (pipaye, PPY). The differences in samples processed using different methods were revealed by unsupervised principal component analysis (PCA). In the scores plot of PCA, honey-processed PPY (PPPY), crude PPY (CPPY), and heated PPY (HPPY) were clearly discriminated. Furthermore, samples processed at different temperatures could also be distinguished; indeed, our PCA results demonstrated the importance of temperature during processing. Two unique marker ions were found to discriminate between PPPY and CPPY by orthogonal partial least squares discriminant analysis (OPLS-DA), which could be used as potential chemical markers. The method was further confirmed by a verification test with commercial PPY. The orthogonal array experiment revealed an optimized processing condition with 50% honey at 140°C for 20 min after 4 h of moistening time, a process that provides significant information for standardized production.

Highlights

The leaf of Eriobotrya japonica (Thunb.) Lindl, commonly referred to as pipaye (PPY), is a well-known and commonly used herb in traditional Chinese medicine (TCM)
Sesquiterpenes, flavonoids, tannins, and megastigmane glycosides have been identified in PPY, and some of them have been found to possess antitumor, antiviral, hypoglycemic, and anti-inflammatory properties [4,5,6,7,8]
In TCM, PPY should be processed before clinical use

Summary

Introduction

The leaf of Eriobotrya japonica (Thunb.) Lindl (loquat), commonly referred to as pipaye (PPY), is a well-known and commonly used herb in traditional Chinese medicine (TCM). Multiple methods have been used to process PPY. These methods include removing the hair on the leaves, heating [9], and heating in the presence of honey or ginger [10]. Among these methods, removing the hair on the leaves is regarded as a necessary step before using PPY. Chemical analysis and determination of optimal processing mechanisms for PPPY have not yet been investigated, despite the fact that PPPY has been used for hundreds of years

Methods

Results

Conclusion