Characterization of chlorophyll breakdown in green prickleyashes (Zanthoxylum schinifolium Zucc.) during slow drying

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.

Determination of main alkylamides responsible for Zanthoxylum bungeanum pungency through quantitative analysis of multi-components by a single marker

The pungency of Chinese pepper (Zanthoxylum bungeanum) is mainly attributed to the alkylamides contained therein. However, the quantitation and application of these alkylamides are hindered by the lack of commercially available standards. Herein, five alkylamides mainly responsible for the pungency of Z. bungeanum were quantified in 31 batch samples of this plant by high-performance liquid chromatography-mass spectrometry and quantitative analysis of multi-components by a single marker (QAMS) to reveal significant differences in composition distribution according to the sample source. The two methods employed for this purpose, namely an external standard method and QAMS, were shown to be consistent, as the corresponding standardized mean difference was below 5.0%. Thus, the developed QAMS method was concluded to be a promising alternative for the comprehensive and effective quality control of Z. bungeanum from different sources.

Analisis Senyawa Aktif Trigeminal Andaliman dengan Variasi Metode Pengeringan dengan Pendekatan GC-MS

Sanshool compounds are the trigeminal active compounds in andaliman (Zanthoxylum acantho-podium DC) with a numbing and tingling sensation. The analysis of such compounds is usually done through HPLC approach; however, limited studies have reported that the analysis of such compounds could be conducted with Gas Chromatography-Mass Spectrometry (GC-MS). This method could save research time and funding by analyzing both sanshools and volatiles simultaneously, which would describe the complete profile of andaliman flavor compounds. This study aimed to confirm the potency of GC-MS in analyzing sanshool compounds and to utilize this method in studying the impact of different drying methods towards andaliman trigeminal active compounds. Andaliman was dried with five drying methods (sun, sunshade, air, oven, and freeze-drying) and was macerated with chloroform, concentrated, and analyzed with GC-MS. The results of this study showed that GC-MS was able to analyze sanshool compounds efficiently. Drying had no statistically significant impact on sanshool quantities extracted from andaliman. Fresh andaliman contained 0.69 % (dry weight basis) of α-sanshool, the main sanshool in andaliman. On the other hand, dried andaliman contained 0.80-1.08% of α-sanshool (dry weight basis). As oven drying managed to produce andaliman with a similar concentration of α-sanshool at a faster time and more affordable cost than other drying methods, oven drying was suggested as the ideal drying method to extend the shelf life of andaliman.

Reading light: leaf spectra capture fine-scale diversity of closely related, hybridizing arctic shrubs

Leaf reflectance spectroscopy is emerging as an effective tool for assessing plant diversity and function. However, the ability of leaf spectra to detect fine-scale plant evolutionary diversity in complicated biological scenarios is not well understood. We test if reflectance spectra (400-2400 nm) can distinguish species and detect fine-scale population structure and phylogenetic divergence - estimated from genomic data - in two co-occurring, hybridizing, ecotypically differentiated species of Dryas. We also analyze the correlation among taxonomically diagnostic leaf traits to understand the challenges hybrids pose to classification models based on leaf spectra. Classification models based on leaf spectra identified two species of Dryas with 99.7% overall accuracy and genetic populations with 98.9% overall accuracy. All regions of the spectrum carried significant phylogenetic signal. Hybrids were classified with an average overall accuracy of 80%, and our morphological analysis revealed weak trait correlations within hybrids compared to parent species. Reflectance spectra captured genetic variation and accurately distinguished fine-scale population structure and hybrids of morphologically similar, closely related species growing in their home environment. Our findings suggest that fine-scale evolutionary diversity is captured by reflectance spectra and should be considered as spectrally-based biodiversity assessments become more prevalent.

Changes in volatiles and aroma profile of andaliman (Zanthoxylum acanthopodium DC.) upon various drying techniques

Andaliman is a highly perishable Indonesian spice that could be preserved by drying. As the drying influence on andaliman volatiles and aroma profile has not been reported, this study aimed to determine the impact of five drying processes on them and the critical volatiles correlated with favorable aroma attributes. Limonene, geranial, α-pinene, sabinene, β-myrcene, (E)-2-hexenal tended to decrease while geranyl acetate, citronellal, neral tended to increase upon drying. Limonene, andaliman major volatiles, was lost considerably from 28093 µg/g solids (fresh) to 19299-21857 µg/g solids (dried). Drying significantly altered citrus, orange peel, green, warm, and lime leaf aroma. Citronellal, limonene, (Z)-β-ocimene, (E)-β-ocimene, β-citronellol, sabinene, and geranial, played substantial roles in andaliman sensory acceptability due to significant correlation to the favorable aroma attributes (citrus, orange peel, acidic). Oven drying was proposed as the ideal drying method because of its short duration, low water activity, superior overall liking, and high volatile content.

Effect of Zanthoxylum alkylamides on lipid metabolism and its mechanism in rats fed with a high-fat diet

This research aimed at exploring the effect of Zanthoxylum alkylamides on lipid metabolism and its potential mechanisms using high-fat diet rat model. Treatment with Zanthoxylum alkylamides for 6 weeks, food efficiency and atherogenic index of the low, medium, and high doses of Zanthoxylum alkylamides-treated groups were significantly reduced. Meanwhile, the histopathological structure of the livers showed that hepatic steatosis in the groups treated with Zanthoxylum alkylamides was reduced, particularly the HD group. Moreover, the related genes were studied, such as, liver X receptor (LXR), cholesterol 7 alpha-hydroxylase (CYP7A1), hepatic 3-hydroxyl-2-methylglutaryl CoA (HMG-CoA) reductase, sterol regulatory element-binding protein 2 (SREBP-2), ileal bile acid-binding protein (IBABP), sodium-dependent bile acid transporter (ASBT), and transient receptor potential vanilloid subtype1 (TRPV1). These results demonstrated that Zanthoxylum alkylamides could ameliorate abnormal lipid metabolism in rats fed with a high-fat diet. The underlying mechanism may be the downregulation of the expression levels of cholesterol synthesis and bile acid reabsorption-related genes, reduction of endogenous cholesterol synthesis, and increase in bile acid and neutral sterol excretion. PRACTICAL APPLICATIONS: High-energy diet is a potential risk of lipid metabolic disorder. Many studies have shown that hyperlipidemia can lead to atherosclerosis and even hemangioma, cerebral thrombosis, coronary heart disease, and other diseases, which seriously threaten human health. Therefore, seeking an effective and safe way to prevent the obesity-related disease is necessary. This research found that Zanthoxylum alkylamide could ameliorate abnormal lipid metabolism in rats fed with a high-fat diet. The underlying mechanism may be the downregulation of the expression levels of cholesterol synthesis and ileal absorption of bile acid genes, reduction of endogenous cholesterol synthesis, and increase in bile acid and neutral sterol excretion. Therefore, Zanthoxylum alkylamide has the potential for preventing or alleviating high-energy intake-related obesity.

Genes associated with agronomic traits in non-heading Chinese cabbage identified by expression profiling

BACKGROUND

The genomes of non-heading Chinese cabbage (Brassica rapa ssp. chinensis), heading Chinese cabbage (Brassica rapa ssp. pekinensis) and their close relative Arabidopsis thaliana have provided important resources for studying the evolution and genetic improvement of cruciferous plants. Natural growing conditions present these plants with a variety of physiological challenges for which they have a repertoire of genes that ensure adaptability and normal growth. We investigated the differential expressions of genes that control adaptability and development in plants growing in the natural environment to study underlying mechanisms of their expression.

RESULTS

Using digital gene expression tag profiling, we constructed an expression profile to identify genes related to important agronomic traits under natural growing conditions. Among three non-heading Chinese cabbage cultivars, we found thousands of genes that exhibited significant differences in expression levels at five developmental stages. Through comparative analysis and previous reports, we identified several candidate genes associated with late flowering, cold tolerance, self-incompatibility, and leaf color. Two genes related to cold tolerance were verified using quantitative real-time PCR.

CONCLUSIONS

We identified a large number of genes associated with important agronomic traits of non-heading Chinese cabbage. This analysis will provide a wealth of resources for molecular-assisted breeding of cabbage. The raw data and detailed results of this analysis are available at the website http://nhccdata.njau.edu.cn.