Fingerprint analysis of Zanthoxylum armatum DC. by HPLC

Degradation and Transformation Mechanisms of Zanthoxylum Alkylamides Exposed to UVB Light

Zanthoxylum oleoresin, a concentrated extract derived from Zanthoxylum bungeanum, is rich in non-volatile, intensely flavorful substances and amide compounds, such as hydroxy-α-sanshool, hydroxy-β-sanshool, and hydroxy-ε-sanshool. The production process of Zanthoxylum oleoresin remains unstandardized, and there is still a lack of research on the precise classification and quantification of its key chemical constituents, as well as the stability of these compounds when produced using different extraction methods. This study utilized preparative liquid chromatography to extract and purify amide compounds from Zanthoxylum oleoresin, successfully isolating three sanshools: hydroxy-α-sanshool, hydroxy-β-sanshool, and hydroxy-ε-sanshool. The stability of three these sanshools under UVB irradiation in different solvents was explored in UVB-simulated sunlight conditions to investigate the degradation or transformation mechanism of Zanthoxylum alkylamides under UVB irradiation. The findings indicate a rapid decrease in the hydroxy-α-sanshool content under UVB ultraviolet light, aligning with the second-order kinetics. This study revealed alterations in the contents of hydroxy-α-sanshool, hydroxy-β-sanshool, and hydroxy-ε-sanshool and the formation of a new compound following exposure to UVB light. This new compound, along with the three sanshools, possesses a uniform m/z 264 and shares similar chemical structures. Further analysis also uncovered that these compounds are capable of undergoing isomerization reactions under UVB irradiation. This demonstrates that UVB irradiation of certain intensities can modify the concentrations and chemical structures of these Zanthoxylum alkylamides. These insights offer crucial guidance for future studies on the processing and preservation of Zanthoxylum alkylamides and their derivatives.

RP-HPLC-Based Flavonoid Profiling Accompanied with Multivariate Analysis: An Efficient Approach for Quality Assessment of Houttuynia cordata Thunb Leaves and Their Commercial Products

Chemical profiling for quality monitoring and evaluation of medicinal plants is gaining attention. This study aims to develop an HPLC method followed by multivariate analysis to obtain HPLC profiles of five specific flavonoids, including rutin (1), hyperin (2), isoquercitrin (3), quercitrin (4), and quercetin (5) from Houttuynia cordata leaves and powder products and assess the quality of H. cordata samples. Eventually, we successfully established HPLC-based flavonoid profiles and quantified the contents of 32 H. cordata fresh leave samples and four powder products. The study also quantified the contents of those five essential flavonoids using an optimized RP-HPLC method. Peak areas of samples were then investigated with principal component analysis (PCA) and hierarchical cluster analysis (HCA) to evaluate the similarity and variance. Principal components in PCA strongly influenced by hyperin and quercetin showed that the samples were clustered into subgroups, demonstrating H. cordata samples' quality. The results of HCA showed the similarity and divided the samples into seven subgroups. In conclusion, we have successfully developed a practical methodology that combined the HPLC-based flavonoid profiling and multivariate analysis for the quantification and quality control of H. cordata samples from fresh leaves and powder products. For further studies, we will consider various environmental factors, including climate and soil factors, to investigate their effects on the flavonoid contents of H. cordata.

The establishment of comprehensive quality evaluation model for flavor characteristics of green Sichuan pepper (Zanthoxylum armatum DC.) in Southwest China

In this study, the quality indexes and sensory evaluation of Zanthoxylum armatum DC. from the main production areas in Southwest China were analyzed. Further, correlation analysis (CRA), principal component analysis (PCA) and cluster analysis (CA) were used to comprehensively evaluate the quality characteristics of Z. armatum. The results showed that the sensory indexes and physicochemical indexes of Z. armatum were significantly correlated. Five principal component factors were extracted from 12 indexes by PCA, and a comprehensive evaluation model of quality was established with Y = 0.2943Y₁ + 0.2387Y₂ + 0.1896Y₃ + 0.1679Y₄ + 0.1094Y₅. On this basis, 21 producing areas were grouped into 4 groups and 3 groups by Q-type CA, respectively. R-type CA showed that the content of hydroxyl-sanshools, linalool content and b* value were the quality characteristic indexes of Z. armatum in Southwest China. This work provided an important theory and practice reference for Z. armatum quality evaluation and in-depth product development.

Comprehensive HPLC fingerprint analysis based on a two-step extraction method for quality evaluation of Perilla frutescens (L.) Britt

Abundant chemical components are key to ensure the evaluation accuracy of fingerprint analysis of traditional Chinese medicines (TCMs). A two-step extraction method combining supercritical fluid extraction (SFE) and water ultrasonic extraction was established for the quality evaluation of Perilla frutescens (L.) Britt. Weakly polar components were extracted under optimal SFE conditions (15% co-solvent (EtOH : n-hexane = 1 : 14, (v/v)), 40 °C, 250 bar, and 30 min), and polar components were subsequently extracted by an ultrasonic step (100% water as solvent, 40 °C, and 45 min). Then, HPLC methods were established, which were validated to be accurate, stable, and reliable. In this work, 25 batches of samples were evaluated and the data were analysed by similarity analysis (SA) and hierarchical cluster analysis (HCA). The similarity values of SFE extracts and aqueous extracts were respectively 0.616-0.999, and 0.252-0.997, proving the importance of the extraction method for the accuracy of the subsequent fingerprint analysis results. For the HCA, 25 samples were divided into two categories (leaves and stems), among which four batches of leaves with less similarity were considered as stems, indicating that quality differences of P. frutescens depending on medicinal parts and origin exist. The two-step extraction method developed in this work has been proved to be suitable for the quality evaluation of TCMs with complex compositions.

"Q-markers targeted screening" strategy for comprehensive qualitative and quantitative analysis in fingerprints of Angelica dahurica with chemometric methods

Angelica dahurica is a famous functional food and herb. To guarantee quality of A. dahurica, a strategy “Q-markers targeted screening” was successfully developed by sufficient extraction of compounds and the targeted screening of qualitative and quantitative markers calculated through chemometric methods based fingerprints. Accelerated solvent extraction was selected due to its prominent advantages exhibiting the maximum extraction yields and varieties of compounds and especially excellent reproducibility (RSD < 1). After extraction, the fingerprints of A. dahuricae samples were established. For the preliminary herb authenticity, the targeted screening of 23 quantitative markers were performed by similarity analysis and hierarchical cluster analysis based on the fingerprints, which were identified by liquid chromatography tandem mass spectrometry (LC-MS). Subsequently, for further quality control, the targeted screening of nine quantitative markers were done by similarity analysis & linear discriminant analysis, which were determined by LC. Lastly, the strategy was successfully applied to quality assessment of A. dahurica samples.

Composition, structure and flavor mechanism of numbing substances in Chinese prickly ash in the genus Zanthoxylum: A review

Chinese prickly ash is known for producing a typical pungent sensation in Sichuan Cuisine. Accumulating evidence suggest a series of health benefits and pharmacological effects associated with prickly ash. Therefore, a systematic analysis of the composition, structural properties, detection, and flavor mechanism of numbing substances is highly necessitated to address their future application. Sanshool-based unsaturated amides are the primary cause of tingling. The numbing substances have poor stability and are prone to oxidation and decomposition reactions due to their highly unsaturated conjugated diene structures. Pungent sensations evoked by different sanshools are distinct, which is attributed to different mechanisms of interaction with membrane ion channels (TRPV1, TRPA1, and KCNK). In this paper, the composition, structural properties (such as isomerization, oxidation), detection, and flavor mechanism of numbing substances of prickly ash were summarized. The prospective application and future research direction of numbing substances in the prickly ash industry were also proposed.

Volatile Oil Profile of Prickly Ash (Zanthoxylum) Pericarps from Different Locations in China

Volatile oils of prickly ash (Zanthoxylum) pericarps have various potential biological functions with considerable relevance to food, pharmacological, and industrial applications. The volatile profile of oils extracted from prickly ash pericarps obtained from 72 plantations in China was determined by gas chromatography and mass spectrometry. Several chemometric analyses were used to better understand the volatile oil profile differences among different pericarps and to determine the key factors that affected geographical variations in the main volatile constituents of oils. A total of 47 constituents were detected with D-limonene, alfa-myrcene, and linalool as the most abundant. The volatile profile of pericarp oils was significantly affected by prickly ash species and some environmental factors, and the key factors that affected volatile profile variations for different prickly ash species were diverse. Chemometric analyses based on the volatile oil profile could properly distinguish Z. armatum pericarps from other pericarps. This study provides comprehensive information on the volatile oil profile of pericarps from different prickly ash species and different plantations, and it can be beneficial to a system for evaluating of pericarp quality. Moreover, this study speculates on the key environmental factors that cause volatile oil variations for each species, and can help to obtain better prickly ash pericarp volatile oils by improving the cultivated environments.

Alkylamide Profiling of Pericarps Coupled with Chemometric Analysis to Distinguish Prickly Ash Pericarps

Because of extensive cultivation areas, various cultivars, nonstandard naming notations, and morphology similarity among relative cultivars, adulteration and associated business fraud may happen in the marketplaces of prickly ash pericarps due to higher financial gain and high-frequency trading. This study presents variations in the chemical components and contents of different prickly ash species from different plantations. Alkylamide profiling of pericarps derived from Zanthoxylum armatum, Z. bungeanum, and some relative Zanthoxylum species from 72 plantations across China were tested using ultra-performance liquid chromatography. Then, several chemometrics were applied to classify the prickly ash pericarps to reveal potential indicators that distinguish prickly ash pericarps and to identify the key factors that affect pericarp alkylamide profiling. The dominating alkylamides in the prickly ash pericarps were Z. piperitum (ZP)-amide C (0–20.64 mg/g) and ZP-amide D (0–30.43 mg/g). Alkylamide profiling of prickly ash pericarps varied significantly across species and geographical variations. ZP-amide D in prickly ash pericarps was identified as a potential indicator to distinguish prickly ash species. Longitude and aluminum content in soils were identified as key factors that affected alkylamide profiling of prickly ash pericarps. This study provides a useful tool to classify prickly ash species based on pericarp alkylamide profiling and to determine the key influence factors on pericarp alkylamide variations.

Multiple-fingerprint analysis of Poria cocos polysaccharide by HPLC combined with chemometrics methods

In this study, the multiple fingerprints, which were integrated with HPGFC-ELSD (high performance gel filtration chromatography - evaporative light scattering detector) fingerprint, PMP-HPLC-DAD (1-phenyl-3-methyl-5-pyrazolone-high performance liquid chromatography - diode array detector) fingerprint of complete acid hydrolysates and HILIC-HPLC-ELSD (hydrophilic interaction - high performance liquid chromatography - evaporative light scattering detector) fingerprint of enzyme hydrolysates, were established to evaluate the quality of polysaccharides from Poria cocos (PCPs). The similarity evaluation showed that 16 batches of PCPs from different origins had high similarity in structural characteristics based on the multiple fingerprints. The chromatographic data of multiple fingerprints of PCPs were fused, processed and analyzed by chemometric methods including HCA (hierarchical cluster analysis), PCA (principal component analysis) and PLS-DA (partial least squares discriminant analysis). The 16 batches of PCPs were divided into 3 categories in PCA, indicating a certain relationship between the structural characteristics and the origins. PLS-DA analysis indicated that Man, Glc, Gal, Fuc, the components with m/z of 2.22 × 10⁴∼1.53 × 10⁴ Da and 3.46 × 10³∼2.69 × 10³ Da, oligosaccharides with DPs of 6 and 7, respectively, could be regarded as potential chemical markers for the classification of PCPs from different origins. According to the multiple fingerprints and chemometric analysis, the two commercial samples were proved to be adulterants.