Chemical constituents from the pericarps of Zanthoxylum bungeanum and their chemotaxonomic significance

New alkylamides from the pericarps of Zanthoxylum schinifolium

The pericarps of Zanthoxylum schinifolium Sieb. et Zucc were called "green huajiao", which were used as traditional folk medicine and popular seasoning in China. In this study, twenty-seven alkylamides, including a rare alkylamide containing two amide groups (1), an alkylamide with a furan ring (5), six new alkylamide analogues (2-4, 6-8), together with nineteen known alkylamides (9-27) were isolated from green huajiao. Their structures were elucidated by extensive spectroscopic analysis, including 1D, 2D NMR, HRESIMS, and UV spectra. Furthermore, compounds 5, 18, 21, and 22 exhibited weak protective activity for corticosterone-induced PC12 cells damage.

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.

Differential Metabolomics Reveals Pathogenesis of Pestalotiopsis kenyana Causing Leaf Spot Disease of Zanthoxylum schinifolium

Pepper leaf spot is a common disease of Zanthoxylum schinifolium. When it is serious, it directly affects the growth of Z. schinifolium, making the plant unable to blossom and bear fruit, which seriously restricts the development of the Z. schinifolium industry. Therefore, the pathogenic mechanism of leaf spots should be explored to provide a basis for a comprehensive understanding of the disease. Using liquid chromatography-mass spectrometry (LC-MS) technology combined with the data-dependent acquisition, the full spectrum analysis of pathogen mycelium samples was carried out. Partial least squares discriminant analysis (PLS-DA) was used to reveal the differences in metabolic patterns among different groups. Hierarchical clustering analysis (HCA) and PLS-DA were used to reveal the relationship between samples and metabolites, which reflected the metabolomics changes of Pestalotiopsis kenyana in the logarithmic growth phase of mycelia, the stable growth phase of mycelia, the massive spore stage, the induction culture conditions of PDA and Z. schinifolium leaves, and the possible pathogenic substances were selected for pathogenicity detection. PLS-DA had a strong predictive ability, indicating a clear analysis trend between different groups. The results of the metabolomics analysis showed that the differential metabolites of pathogenic bacteria were abundant at different stages and under different medium conditions, and the content of metabolites changed significantly. There were 3922 differential metabolites in nine groups under positive and negative ion modes, including lipids and lipid molecules, organic acids and their derivatives, organic heterocyclic compounds, organic oxygen compounds, carbohydrate polyketides, nucleosides, nucleotides, and analogs. The results of the pathogenicity test showed that the leaves treated with 3,5-dimethoxy benzoic acid, S-(5-adenosy)-l-homocysteine, 2-(1H-indol-3-yl) acetic acid, l-glutamic acid, and 2-(2-acetyl-3,5-dihydroxy phenyl) acetic acid showed different degrees of yellowish-brown lesions. This indicated that these substances may be related to the pathogenicity of P. kenyana, and the incidence was more serious when treated with 3,5-dimethoxybenzoic acid and S-(5-adenosy)- l -homocysteine. This study provides a basis for further analysis of differential metabolites and provides a theoretical reference for the prevention and treatment of Z. schinifolium leaf spot.

Degradation and transformation mechanisms of numbing substances: Hydroxyl-α-sanshool & hydroxyl-β-sanshool from Zanthoxylum bungeanum exposed to acid environment

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Isomerization and addition reactions of sanshools reduced the numbing degree for the first time.

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Acidic environment promotes isomerization and addition reactions of numbing substances.

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The degradation rates of hydroxyl-α-sanshool was 75.36%.

In present work, Zanthoxylum bungeanum meal (ZBM) used as experimental material, the stability of typical alkylamides (hydroxyl-α-sanshool and hydroxyl-β-sanshool) in ZBM under different acidification conditions was investigated, in order to reveal degradation or transformation mechanism of numbing substances from Z. bungeanum exposed to acid environment and its transform direction. The alkylamides content of ZBM was detected by using HPLC after different conditions of acidification. The results indicated that hydroxyl-α-sanshool and hydroxyl-β-sanshool under the concentration of hydrochloric acid is 14% decreased by 80% after only 0.5 h. Moreover, some of the components undergo isomerization and addition reactions in the process of acidification, the products of isomerization are hydroxyl-ε-sanshool and (1Z,2E,4E,8E,10E)-N-(2-hydroxy-2-methylpropyl)dodeca-2,4,8,10-tetraenimidic acid; and the product of the addition reaction is (2E,6E,8E,10E)-1-chloro-1-(2-hydroxy-2-methylpropyl)amino)dodeca-2,6,8,10-tetraen-1-ol, which indicated that acid environment has greatly changed the numbing substances in Z. bungeanum and its products.

Dissipation of imidacloprid and its metabolites in Chinese prickly ash (Zanthoxylum) and their dietary risk assessment

Dissipation of imidacloprid (IMI) and its metabolites (urea, olefin, 5-hydroxy, guanidine, 6-chloronicotinic acid) in Chinese prickly ash (CPA) was investigated using QuEChERS combined with UPLC-MS/MS. Good linearity (r² ≥0.9963), accuracy (recoveries of 71.8-104.3%), precision (relative standard deviations of 0.9-9.4%), and sensitivity (limit of quantification ≤0.05 mg kg^-1) were obtained. After application of IMI at dosage of 467 mg a.i. L^-1 for three times with interval of 7 d, the dissipation dynamics of IMI in CPA followed first-order kinetics, with half-life of 6.48-7.29 d. IMI was the main compound in CPA, followed by urea and guanidine with small amounts of olefin, 5-hydroxy, and 6-chloronicotinic acid. The terminal residues of total IMI and its metabolites at PHI of 14-21 d were 0.16-7.80 mg kg^-1 in fresh CPA and 0.41-10.44 mg kg^-1 in dried CPA, with the median processing factor of 3.62. Risk assessment showed the acute (RQa) and chronic dietary risk quotients (RQc) of IMI in CPA were 0.020-0.083% and 0.052-0.334%, respectively. Based on the dietary structures of different genders and ages of Chinese people, the whole dietary risk assessment indicated that RQc was less than 100% for the general population except for 2- to 7-year-old children (RQc of 109.9%), implying the long-term risks of IMI were acceptable to common consumers except for children.