Comparative Analysis of Free Amino Acids and Nucleosides in Different Varieties of Mume Fructus Based on Simultaneous Determination and Multivariate Statistical Analyses

Quality Evaluation and Browning Control in the Multi-Stage Processing of Mume Fructus (Wumei)

The dried Mume Fructus (MF), called Wumei in China, is a unique food with medicinal and edible effects. But its actual production method is outdated with low efficiency and inconsistent quality. This study systematically investigated the influence of moisture content (MC), temperature, and relative humidity (RH) on the browning reaction and quality characteristics of the MF and proposed a continuous processing strategy of the three-stage variable process for MF production based on the precise process control of the temperature and the RH. The production process of MF was divided into three stages: preliminary dehydration, browning, and drying. The results showed that the browning reaction rate and drying efficiency were optimal when the MC of the raw materials was reduced to 50%. In the browning stage, the degree of browning was better, and the antioxidant capacity reached the maximum of 64.38 mg/g DM under a processing temperature of 80 °C and an RH of more than 60%. As the RH increased, the drying rate decreased, and the ash content exhibited an increase. Therefore, the optimal processing parameters for the browning stage were determined to be a temperature of 80 °C and an RH of 60%. In the final drying stage, a temperature of 60 °C coupled with a dehumidification mode proved sufficient to ensure efficient drying without compromising the quality of the MF. This study revealed the reaction mechanism of the rapid browning processing of MF, which has important guiding significance for the rapid processing of browning foods.

Comparative Investigation of the Differences in Chemical Compounds between Raw and Processed Mume Fructus Using Plant Metabolomics Combined with Chemometrics Methods

Mume Fructus is a well-known herbal medicine and food with a long history of processing and application. Different processing methods impact the intrinsic quality of Mume Fructus. Thus, it is of great significance to investigate the changes in chemical components during processing (i.e., raw compared to the pulp and charcoal forms). In this study, plant metabolomics methods based on mass spectrometry detection were established to analyze the chemical ingredients of Mume Fructus comprehensively. Chemometric strategies were combined to analyze the profile differences of Mume Fructus after different processing methods. The established strategy identified 98 volatile and 89 non-volatile compounds of Mume Fructus by gas chromatography-mass spectrometry (GC-MS) and ultra-high performance liquid chromatography coupled with quadrupole time of flight mass spectrometry (UHPLC-Q-TOF-MS/MS), respectively. Moreover, the orthogonal partial least squares discriminant analysis (OPLS-DA) indicated that raw Mume Fructus and the Mume Fructus pulp and charcoal were distributed in three regions. Subsequently, 19 volatile and 16 non-volatile components were selected as potential chemical component markers with variable importance in the projection using (VIP) >1 as the criterion, and the accuracy was verified by a Back Propagation Neural Network (BP-NN). To further understand the difference in the content of Mume Fructus before and after processing, 16 non-volatile chemical component markers were quantitatively determined by ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS/MS). The results revealed that, compared with raw Mume Fructus, the total content of 16 components in the pulp of Mume Fructus increased while it decreased in the charcoal. Therefore, this study used GC-MS, UHPLC-Q-TOF-MS/MS and UHPLC-MS/MS modern technology to analyze the differences in chemical components before and after the processing of Mume Fructus and provided a material basis for further research on the quality evaluation and efficacy of Mume Fructus.

Multi-component pharmacokinetic study of prunus mume fructus extract after oral administration in rats using UPLC-MS/MS

Prunus mume fructus (MF) is used in traditional Chinese medicine and food, as it exerts pharmacological effects, such as antibacterial, antioxidant, antitumour, thirst-relieving, and antidiarrheal effects. In the present study, a reliable and sensitive ultra-high performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the simultaneous determination of 16 prototype components (L-(-)-malic acid, 3,4-dihydroxybenzaldehyde, protocatechuic acid, vanillic acid, caffeic acid, D-(-)-quinic acid, citric acid, ferulic acid, syringic acid, cryptochlorogenic acid, neochlorogenic acid, chlorogenic acid, amygdalin, maslinic acid, corosolic acid, and rutin) in rat plasma after oral administration of the MF extract. Plasma samples were prepared via protein precipitation using acetonitrile. The 16 components were separated on an ACQUITY UPLC BEH C18 column (2.1 × 100 mm, 1.7 μm) with a gradient mobile phase system of methanol and 0.1% (v/v) formic acid aqueous solution at a flow rate of 0.3 ml/min. All components were quantitated using Agilent Jet Stream electrospray ionisation in negative ion mode. The intra-day and inter-day accuracies ranged from-9.4 to 9.4%, and the precision of the analytes was less than 14.8%. The extraction recovery rate of the analytes ranged from 63.59 to 109.44% and the matrix effects ranged from 49.25 to 109.28%. Stability studies proved that the analytes were stable under the tested conditions, with a relative standard deviation lower than 13.7%. Hence, the developed method was successfully applied to evaluate the pharmacokinetics of 16 components in the MF extract after oral administration in rats using UPLC-MS/MS.

Quality evaluation of Tetrastigma hemsleyanum different parts based on quantitative analysis of 42 bioactive constituents combined with multivariate statistical analysis

INTRODUCTION

The root of Tetrastigma hemsleyanum (RTH) has been widely used as a folk medicine in China. Meanwhile, its stems (STH) and leaves (LTH) are consumed as functional tea and food supplementation. Therefore, it is important to get a better understanding of the distribution of bioactive constituents in different parts of T. hemsleyanum.

OBJECTIVE

To develop a method for quantitative analysis of multiple bioactive constituents and comparing their distribution in RTH, STH and LTH.

METHODS

Ultra-performance liquid chromatography triple quadrupole ion trap tandem mass spectrometry (UPLC-QTRAP-MS/MS) was used for the quantitative analysis. The quantitative data were further analysed by principal component analysis (PCA), hierarchical cluster analysis (HCA) and partial least squares determinant analysis (PLS-DA).

RESULTS

Forty-two constituents in RTH, STH and LTH, including 14 flavonoids, three phenolic acids, 15 amino acids and 10 nucleosides, were quantitatively determined. The contents of flavonoids and phenolic acids in LTH were significantly higher than those in RTH and STH. While the contents of amino acids and nucleosides in LTH were less than those in RTH and STH. Multivariate statistical analysis can significantly classify and distinguish RTH, STH, and LTH.

CONCLUSIONS

The present method would be helpful for the quality control of T. hemsleyanum, and the results would be useful for the efficient utilisation of T. hemsleyanum in the future.

Ultra-performance liquid chromatography-quadrupole-time of flight tandem-mass spectrometry and liquid chromatograph-tandem mass spectrometer combined with chemometric analysis an approach for the quality evaluation of Mume Fructus

Mume Fructus is an important traditional Chinese medicine that has been widely used in the treatment of intestinal diseases and asthma for thousands of years. In order to evaluate the quality of Mume Fructus in different processing methods, the main chemical components in Mume Fructus were investigated and a method was established for simultaneous quantification organic acids of Mume Fructus. Firstly, an optimized ultra-performance liquid chromatography-quadrupole-time of flight tandem-mass spectrometry method was used to identify the structures of main components in Mume Fructus. A total of 41 chemical compounds were identified, including 11 organic acids, 13 flavonoids and 3 fatty acids. The contents of 11 organic acids in 18 batches of Mume Fructus from different processing methods were simultaneously determined by LC-MS/MS method. The results of quantitative and hierarchical cluster analysis indicated that Mume Fructus under different processing methods were rich in the above 11 organic acids and the contents were obvious different. Taken together, the proposed quality evaluation method was fast and comprehensively reflects the content of the main chemical components in Mume Fructus under different processing methods, and provides a useful reference for the quality control and evaluation of Mume Fructus. This article is protected by copyright. All rights reserved.