Chemotaxonomic studies of nine Paris species from China based on ultra-high performance liquid chromatography tandem mass spectrometry and Fourier transform infrared spectroscopy

Characterization and Comparison of Steroidal Glycosides from Polygonatum Species by High-Performance Liquid Chromatography-Electrospray Ionization Mass Spectrometry

Polygonatum species have been used as traditional medicines and functional foods in Asia and Europe since ancient times. In this study, a fast and simple method based on liquid chromatography coupled with electrospray ionization mass spectrometry (LC-ESI-MS) was developed to systematically analyze and identify the steroidal glycosides in four major Polygonatum species distributed in Japan, including P. odoratum, P. falcatum, P. macranthum, and P. sibiricum. As a result, 31 steroidal glycosides were tentatively identified, including 18 known and 13 previously unreported glycosides. Their structures were identified by the interpretation of chromatographic behavior and ESI-MS fragmentation patterns. The identification of 31 steroidal glycosides was indicative of a common biogenetic pathway in Polygonatum species. Our study disclosed the chemical profiling of steroidal glycosides in the plants of Polygonatum species, which will benefit better phytochemotaxonomical and phytochemical understanding and quality control for their medicinal usage.

Molecular-networking-guided discovery of species-specific markers for discriminating five medicinal Paris herbs

BACKGROUND

Paridis Rhizoma (PR) is a famous traditional herbal medicine. Apart from two officially recorded species, viz. Paris polyphylla Smith var. yunnanensis (Franch.) Hand. - Mazz. (PPY) and P. polyphylla Smith var. chinensis (Franch.) Hara (PPC), there are still many other species used as folk medicine. It is necessary to understand the metabolic differences among Paris species.

PURPOSE

To establish a strategy that can discover species-specific steroidal saponin markers to distinguish closely-related Paris herbs for quality and safety control.

METHODS

A new strategy of molecular-networking-guided discovery of species-specific markers was proposed. Firstly, the ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS) was applied to obtain the MS and MS/MS data of all samples. Then, molecular networking (MN) was created using MS/MS data to prescreen the steroidal saponins for subsequent analysis. Next, the principal component analysis (PCA) and orthogonal partial least square discriminant analysis (OPLS-DA) models were established to discover potential markers. Finally, the verification, identification and distribution of chemical markers were performed.

RESULTS

A total of 126 steroidal saponins were screened out from five species using MN. Five species were classified successfully by OPLS-DA model, and 18 species-specific markers were discovered combining the variable importance in the projection (VIP) value, P value (one-way ANOVA) and their relative abundance. These markers could predict the species of Paris herbs correctly.

CONCLUSION

These results revealed that this new strategy could be an efficient way for chemical discrimination of medicinal herbs with close genetic relationship.

Molecular mechanisms of anticancer activities of polyphyllin VII

Cancer is the leading cause of mortality in the world. The major therapies for cancer treatment are chemotherapy, surgery, and radiation therapy. All these therapies expensive, toxic and show resistance. The plant-derived compounds are considered safe, cost-effective and target cancer through different pathways. In these pathways include oxidative stress, mitochondrial dependent and independent, STAT3, NF-kB, MAPKs, cell cycle, and autophagy pathways. One of the new plants derived compounds is Polyphyllin VII (PPVII), which target cancer through different molecular mechanisms. In literature, there is a review gap of studies on PPVII; therefore in the current review, we summarized the available studies on PPVII to provide a base for future research.

Structural characterization and discrimination of Paris polyphylla var. yunnanensis by a molecular networking strategy coupled with ultra-high-performance liquid chromatography with quadrupole time-of-flight mass spectrometry

RATIONALE

Paris polyphylla var. yunnanensis (Franch) Hand Mazz (PPY) is a traditional Chinese medicine with antitumor, antibacterial, hemostatic, and anthelmintic activities. Identification of the chemical composition in PPY is helpful to discover its active ingredients and can be used to establish its quality control protocols.

METHODS

The composition of PPY was identified using ultra-high-performance liquid chromatography combined with quadrupole time-of-flight mass spectrometry (UHPLC/QTOF-MS/MS) coupled with a molecular networking strategy. First, the UHPLC/QTOF-MS/MS approach was optimized for chemical compound profiling. Then, the MS data were processed using PeakView™ combined with an in-house database to quickly characterize the secondary metabolites. Finally, molecular networking excavated new molecular weights to discover unknown or trace natural products based on the characteristics of each cluster.

RESULTS

A total of 222 compounds, including 77 isospirostanols, 2 spirostanols, 19 furostanols, 10 pseudospirostanols, 6 cholesterols, 10 C₂₁ steroids, 5 insect metamorphosis hormones, 3 plant sterols, 6 five-ring triterpenoids, 4 flavonoids, 8 fatty acids, 2 phenylpropanoids, and 8 other compounds, were characterized in PPY by comparing their main fragmentation characteristics and pathways with the literature data, and 62 of them, 54 steroidals and 8 phenylpropanoids, were discovered or tentatively identified for the first time.

CONCLUSIONS

This study extended the application of a molecular networking strategy to traditional herbal medicines and developed a molecular networking based screening approach with a significant increase in efficiency for the discovery and identification of trace novel natural products.

Chemotaxonomic studies of 12 Dioscorea species from China by UHPLC-QTOF-MS/MS analysis

INTRODUCTION

Dioscorea species, which contain abundant steroidal saponins, have been used as folk medicines or raw materials to synthesise steroid drugs.

OBJECTIVE

To establish a rapid chemotaxonomic method that will comprehensively resolve confusions about genetic relationships of genus Dioscorea.

METHODS

A comprehensive strategy using ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UHPLC-QTOF-MS/MS) was firstly proposed to evaluate the chemotaxonomy of 12 species (27 taxa) from China by hierarchical cluster analysis (HCA) based on the variations of the identified metabolites.

RESULTS

Twenty-eight secondary metabolites (mainly steroidal saponins) were identified. The MSⁿ fragmentation patterns of DA (a new acetylated steroidal saponin at C-7 position) were firstly reported. Moreover, eight major steroidal saponins were further quantified simultaneously by UPLC-QTOF-MS method. According to HCA results, D. bulbifera L. was distinguished with species of sect. Stenophora Uline for pennogenin-type steroidal saponins. Dioscorea zingiberensis exhibited far distance from other members of sect. Stenophora Uline for two unique saponins. Dioscorea banzhuana may be reclassified into sect. Stenophora. Dioscorea nipponica subsp. rosthornii and D. collettii var. hypoglauca might be separated from their original subspecies/varieties as new species, respectively.

CONCLUSION

The chemotaxonomic method was successfully applied in the study of genetic relationships of Dioscorea species. This study not only enhanced the understanding of chemical constituents, but also laid basic theoretical foundations for the rational utilisation and chemotaxonomy of genus Dioscorea.

Capturing the Geoherbalism Differentiation in Wild Paris polyphylla var. yunnanensis Raw Materials through the Application of Multispectral Information Fusion Combined with Chemometrics

Paris polyphylla var. yunnanensis is a famous medicinal plant distributed in some Asian countries. This species has attracted a great deal of attention and is often used as raw materials in traditional medicine practices. With the purpose of gaining insight into the geoherbalism of wild P. polyphylla var. yunnanensis, a total of 183 dried rhizome samples from eight different regions including 16 typical or nontypical natural habitats have been analyzed by multispectral information fusion based on ultraviolet and Fourier transform infrared spectroscopies combined with partial least squares discriminant analysis (PLS-DA) and hierarchical cluster analysis. From the results, the use of multispectral information fusion strategy could improve the correct classification of samples, and good classification performances have been shown according to PLS-DA models. The discrimination of samples was obtained successfully with respect to the typical and nontypical natural habitats, different collection areas of typical natural habitats, and various sampling sites in nontypical natural habitats. Additionally, the similarities among samples were presented as well. Overall, the rhizome of wild P. polyphylla var. yunnanensis exhibited various regional dependence and individual differences according to the geographical origins, and the relatively appropriate growth region with better quality consistency of samples was preliminarily selected. This study also revealed that the developed multispectral information fusion method has the potential to be a reliable analytical methodology for capturing the geoherbalism differentiation in wild P. polyphylla var. yunnanensis. Furthermore, it could provide more chemical evidence for the critical supplement of quality evaluation on P. polyphylla var. yunnanensis.

Data Fusion of Fourier Transform Mid-Infrared (MIR) and Near-Infrared (NIR) Spectroscopies to Identify Geographical Origin of Wild Paris polyphylla var. yunnanensis

Origin traceability is important for controlling the effect of Chinese medicinal materials and Chinese patent medicines. Paris polyphylla var. yunnanensis is widely distributed and well-known all over the world. In our study, two spectroscopic techniques (Fourier transform mid-infrared (FT-MIR) and near-infrared (NIR)) were applied for the geographical origin traceability of 196 wild P. yunnanensis samples combined with low-, mid-, and high-level data fusion strategies. Partial least squares discriminant analysis (PLS-DA) and random forest (RF) were used to establish classification models. Feature variables extraction (principal component analysis—PCA) and important variables selection models (recursive feature elimination and Boruta) were applied for geographical origin traceability, while the classification ability of models with the former model is better than with the latter. FT-MIR spectra are considered to contribute more than NIR spectra. Besides, the result of high-level data fusion based on principal components (PCs) feature variables extraction is satisfactory with an accuracy of 100%. Hence, data fusion of FT-MIR and NIR signals can effectively identify the geographical origin of wild P. yunnanensis.

Structural characterisation and discrimination of the aerial parts of Paris polyphylla var. yunnanensis and Paris polyphylla var. chinensis by UHPLC-QTOF-MS coupled with multivariate data analysis

INTRODUCTION

As sources of Rhizoma Paridis are facing shortages, utilising the aerial parts of Paris polyphylla has emerged as a promising additional source. However, the components in the aerial parts still need to be explored, and it is difficult to distinguish the aerial parts of P. polyphylla Smith var. yunnanensis (PPY) and P. polyphylla var. chinensis (PPC), two varieties of P. polyphylla.

OBJECTIVE

This study aimed to establish a comprehensive platform to characterise steroid saponins from the aerial parts of PPY and PPC and to discriminate these two varieties.

METHODOLOGY

A dereplication approach and ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) analysis were used for the characterisation of steroidal saponins in the aerial parts of PPY and PPC. Multivariate statistical analysis was performed to differentiate these two varieties and screen discriminant variables. In addition, a genetic algorithm-optimised for support vector machines (GA-SVM) model was developed to predict P. polyphylla samples. The distribution of steroidal saponins in PPY and PPC was visualised by a heatmap.

RESULTS

A total of 102 compounds were characterised from the aerial parts of PPY and PPC by dereplication. A clear separation of PPY and PPC was achieved, and 35 saponins were screened as marker compounds. The established GA-SVM model showed excellent prediction performance with a prediction accuracy of 100%.

CONCLUSIONS

Many steroid saponins that have been reported in Rhizoma Paridis also exist in the aerial parts of P. polyphylla. Samples from the aerial parts of PPY and PPC could be discriminated using our platform.

Comparative analysis of proteomic and metabolomic profiles of different species of Paris

An extract prepared from species of Paris is the most widely consumed herbal product in China. The genus Paris includes a variety of genotypes with different medicinal component contents but only two are defined as official sources. Closely related species have different medicinal properties because of differential expression of proteins and metabolites. To better understand the molecular basis of these differences, we examined proteomic and metabolomic changes in rhizomes of P. polyphylla var. chinensis, P. polyphylla var. yunnanensis, and P. fargesii var. fargesii using a technique known as sequential window acquisition of all theoretical mass spectra as well as gas chromatography-time-of-flight mass spectrometry. In total, 419 proteins showed significant abundance changes, and 33 metabolites could be used to discriminate Paris species. A complex analysis of proteomic and metabolomic data revealed a higher efficiency of sucrose utilization and an elevated protein abundance in the sugar metabolic pathway of P. polyphylla var. chinensis. The pyruvate content and efficiency of acetyl-CoA-utilization in saponin biosynthesis were also higher in P. polyphylla var. chinensis than in the other two species. The results expand our understanding of the proteome and metabolome of Paris and offer new insights into the species-specific traits of these herbaceous plants. SIGNIFICANCE: The traditional Chinese medicine Paris is the most widely consumed herbal product for the treatment of joint pain, rheumatoid arthritis and antineoplastic. All Paris species have roughly the same morphological characteristics; however, different members have different medicinal compound contents. Efficient exploitation of genetic diversity is a key factor in the development of rare medicinal plants with improved agronomic traits and malleability to challenging environmental conditions. Nevertheless, only a partial understanding of physiological and molecular mechanisms of different plants of Paris can be achieved without proteomics. To better understand the molecular basis of these differences and facilitate the use of other Paris species, we examine proteomic metabolomic changes in rhizomes of Paris using the technique known as SWATH-MS and GC/TOF-MS. Our research has provided information that can be used in other studies to compare metabolic traits in different Paris species. Our findings can also serve as a theoretical basis for the selection and cultivation of other Paris species with a higher medicinal value.