Characterization and Comparison of the Pungent Components in Commercial Zanthoxylum bungeanum Oil and Zanthoxylum schinifolium Oil

Degradation and transformation mechanisms of pungent substances in huajiao (Zanthoxylum bungeanum) oil during storage: Induced by ultraviolet irradiation

The pungency of huajiao (scientifically known as Zanthoxylum bungeanum) oil (ZBO), a crucial seasoning oil, is notably influenced by storage conditions, an aspect insufficiently explored in current research. Through the use of high-performance liquid chromatography and liquid chromatography-mass spectrometry, this study systematically investigated the stability of pungent compounds in ZBO under various storage conditions. It also elucidated the degradation and transformation mechanisms of these substances when exposed to ultraviolet (UV) irradiation. The results underscore elevated temperature, light exposure, oxygen, and storage duration as pivotal factors influencing compound degradation, with UV light emerging as the primary driving force. After 48 h of UV exposure, the primary pungent compound, hydroxy-α-sanshool, experienced a significant loss of 85.49%, indicating a pronounced inclination towards isomerization and oxidation. Notably, this study reveals, for the first time, the possible degradation-transformation pattern of hydroxy-γ-sanshool: a mutual conversion with hydroxy-γ-isosanshool and isomerization to (2E,4E,8Z,10E,12Z)-N-(2-hydroxy-2-methylpropyl) tetradeca-2,4,8,10,12-pentaenamide.

A Simple and Rapid High-Performance Liquid Chromatography Method for Preparation and Content Detection of the Mainly Numbing Taste Substances of Zanthoxylum bungeanum Maxim

As the characteristic numbing taste substances, hydroxyl-α-sanshool (HAS) and hydroxyl-β-sanshool (HBS) were considered vital indicators to evaluate the quality of Zanthoxylum bungeanum Maxim. However, it is very difficult to obtain their high-purity monomers individually, as the only difference between HAS and HBS is that C-6 cis-trans isomerism. In our study, a simple and rapid Ag +-HPLC method was developed to pure the standard chemicals of Z. bungeanum with numbing taste, and 1H NMR and 13C NMR were employed to determine the purity and structure. Moreover, an HPLC method was established to determine the content of numbing taste components of 16 varieties of Z. bungeanum from different regions. The analytical methods were validated for accuracy, precision, and linearity, respectively. The validated method was accurate (spiked recoveries 0.94-1.10), precise in terms of peak area (intra-day RSDs <1.25% and inter-day RSDs <1.61%), and linear (r2 ≥ 0.999). It was found that there were significant differences in the content of HAS and HBS among different types of Z. bungeanum, with HAS content ranging from 60.06 ± 1.14 to 164.13 ± 3.28 mg/g and HBS ranging from 7.81 ± 0.36 to 21.11 ± 0.75 mg/g. The RSDs of HAS range were 1.73-3.80% and that of HBS range 2.03-4.73% (RSDs ≤5%), which indicated that the measurements of HAS and HBS were reliable.

Stability of Hydroxy-α-Sanshool in Medium-Chain Triglyceride Oil and Corresponding Oil/Water Emulsions

The pungent component of sansho (Japanese pepper, Zanthoxylum pipritum) is sanshool, which is easily oxidized and decomposed. We have previously reported several sanshool stabilizers, such as α-tocopherol (α-Toc). Sansho pericarp powder treated with middle-chain triglycerides (MCTs) can be used to obtain extracts containing hydroxy-α-sanshool (HαS). Although HαS is stabilized when α-Toc is added to the MCT extracts, the loss of HαS is accelerated when it is mixed with a powder such as lactose. The separation of α-Toc from sanshools was thought to inevitably lead to their oxidation. Therefore, using sansho pericarp MCT extracts with or without α-Toc, oil/water (o/w) emulsions were prepared by adding a surfactant, glycerin, and water to these extracts. In both emulsions, HαS was stable in accelerated tests at 50 °C. However, when lactose powder was added to the emulsions and an accelerated test was performed, HαS in the emulsion containing α-Toc was stable, but HαS in the emulsion without α-Toc was unstable. These results highlight the importance of maintaining the close proximity of HαS and α-Toc in the emulsion. The stabilization of sanshools using emulsion technology can facilitate the production of various processed beverages, foods, cosmetics, and pharmaceuticals containing Japanese pepper.

Stabilization of Hydroxy-α-Sanshool by Antioxidants Present in the Genus Zanthoxylum

Japanese pepper (sansho, Zanthoxylum piperitum) contains several types of sanshools belonging to N-alkylamides. Because of the long-chain unsaturated fatty acids present in their structure, sanshools are prone to oxidative deterioration, which poses problems in processing. In this paper, we evaluated the effects of antioxidants from the genus Zanthoxylum in preventing sanshool degradation using accelerated tests. An ethanolic extract of segment membranes of the sansho fruit pericarp was incubated at 70 °C for 7 days with different antioxidants to determine the residual amount of hydroxy-α-sanshool (HαS) in the extract. α-Tocopherol (α-Toc) showed excellent HαS-stabilizing activity at low concentrations. Among phenolic acids, we noted that the HαS-stabilizing activity increased with the number of hydroxy groups per molecule. For example, gallic acid and its derivatives exhibited excellent sanshool-stabilizing activity. Quercetin was found to be a superior HαS stabilizer compared with hesperetin and naringenin. However, the effective concentration was much higher for phenolic compounds than for α-Toc. These substances are believed to play a role in preventing the decomposition of sanshools in the pericarp of sansho. These sanshool stabilizers should be useful in the development of new beverages, foods, cosmetics, and pharmaceuticals that take advantage of the taste and flavor of sansho.

SERS determination of hydroxy-α-sanshool in spicy hotpot seasoning: The strategy to restrain the interference of capsaicin and its mechanism

Hydroxy-α-sanshool (α-SOH) is the principal ingredient responsible for the numbing sensation in spicy hotpot. However, utilizing surface-enhanced Raman scattering (SERS) to analyze the α-SOH in hotpot seasoning is challenging due to the significant interference of capsaicin (CAP). Therefore, two schemes were proposed to address CAP interference in hotpot seasoning, namely laccase-catalyzed conversion and metal-organic framework (MOF) interaction. Among them, Fe-BTC MOF exhibited significant anti-interference effect and the underlying mechanism is elucidated. The motion of CAP aromatic ring was constrained by steric hindrance and electrostatic interactions of Fe-BTC. Additionally, the interaction between CAP aromatic ring and conjugated triene group in α-SOH was quenched, enhancing the α-SOH SERS signal. The proposed method had a significant anti-interference effect on α-SOH quantification in the presence of CAP, significantly enhancing the α-SOH SERS signal in a range of 0.85 to 4.00 × 10⁷. The linearity and reproducibility of the proposed hotpot seasoning testing method were also validated.

Multi-environment evaluations across ecological regions reveal climate and soil effects on amides contents in Chinese prickly ash peels (Zanthoxylum bungeanum Maxim.)

BACKGROUND

Environmental factors difference is the key factor for the difference in the production, transformation and accumulation of effective components in plants. UPLC-MS/MS and multivariate statistical methods were applied to describe the region difference of amides compounds in Chinese prickly ash peels from different regions and their correlation with climatic factors and soil factors.

RESULTS

Amides compounds contents were significantly higher in high altitude areas, with obvious altitude change trend. Two ecotypes were classified based on the amides compounds contents, one was the high altitude-cool type from Qinghai, Gansu, Sichuan and western Shaanxi province, and the other one was low altitude-warm type from eastern Shaanxi, Shanxi, Henan, Hebei and Shandong province. Amides compounds content were negatively correlated with annual mean temperature, max temperature of warmest month, mean temperature of wettest quarter and mean temperature of warmest quarter (P < 0.01). Except for hydroxy-γ-sanshool and ZP-amide A, the residual amides contents were significantly positively correlated with organic carbon, available nitrogen, phosphorus and potassium in soil and negatively correlated with soil bulk density. Low temperature, low precipitation and high organic carbon in soil were conducive to amides accumulation.

CONCLUSIONS

This study aided in site specific exploration of high amides contents yielding samples, enriched the environment factors effects on amides compounds, and provided scientific foundation for the improvement of Chinese prickly ash peels quality and the location of high-quality production areas.

Simultaneous Analysis of Bergapten and Schinifoline in Zanthoxylum schinifolium Seeds Using HPLC and UPLC-MS/MS Systems

Zanthoxylum schinifolium Siebold et Zuccarini belongs to the Rutaceae family and has been widely used as a spice in East Asian countries such as Korea, China, and Japan. The present study focused on developing and validating a simultaneous analytical method for marker substances (bergapten and schinifoline) in Z. schinifolium seeds. This was achieved using high-performance liquid chromatography with a photo-diode array detector (HPLC-PDA) and ultra-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) systems. In the regression equation, all markers showed a coefficient of determination of ≥0.9990. Marker recovery was 96.90-105.16% (relative standard deviation (RSD) ≤ 2.23), and the intra- and interday precision was RSD < 3.00. Bergapten and schinifoline were detected in the seeds at 1.70-2.85 mg/g and 0.19-0.94 mg/g, respectively. This analytical method will improve quality control of Z. schinifolium seeds. Additionally, this assay will provide basic data and quality assurance for future biological activity experiments or clinical applications.

The Effects of Pepper (Zanthoxylum bungeanum) from Different Production Areas on the Volatile Flavor Compounds of Fried Pepper Oils Based on HS-SPME-GC-MS and Multivariate Statistical Method

Fried pepper oil retains the overall flavor outline of pepper, and its unique rich and spicy flavor is deeply loved by consumers. In order to study the effect of different production areas of pepper on the flavor compounds of fried pepper oil, taking dried pepper from seven different production areas as raw materials, and taking rapeseed oil as a carrier oil as well as a constant frying temperature to prepare pepper oil, the present study analyzed the volatile flavor components of pepper oil qualitatively and quantitatively by employing headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS). The principal component analysis (PCA) method was used to construct the correlation analysis model of volatile flavor substances among different samples of pepper oil. Applying the hierarchical cluster analysis (HCA), the main volatile substances causing the flavor differences of pepper oil from different production areas were identified. The results showed that a total of 81 chemical components were identified, including 15 alcohols, 10 aldehydes, 5 ketones, 34 hydrocarbons, 11 esters, 6 acids, and others. Terpinen-4-ol, linalool, 2,4-decadienal, trans-2-heptenal, sabinene, linalyl acetate, bornyl acetate, myrcene, 1-caryophyllene, trans-α-ocimene, and limonene were selected as the main substances leading to the flavor differences among the pepper oil samples. These 11 chemical components played a decisive role in the construction of the overall aroma of the pepper oil. Using a descriptive sensory analysis, it was concluded that pepper oil from different production areas holds different aroma intensities. Compared with the other six samples, S4 Hanyuan Pepper Oil (HYPO) shows a relatively strong trend toward a spicy fragrance, fresh grassy fragrance, floral and fruity fragrance, fresh sweet fragrance, and fatty aroma.

Application of response surface methodology (RSM) for optimization of the supercritical CO2 extract of oil from Zanthoxylum bungeanum pericarp: Yield, composition and gastric protective effect

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Supercritical carbon-dioxide (SC-CO₂) extract is an effective technology for flavor components of Z. bungeanum pericarp.

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About 11.07 % oil yield can be obtained under the optimized parameters of 30 MPa, 43 °C, and 75 min.

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Limonene, linalool, hydroxy-α-sanshool and hydroxy-β-sanshool are the major flavor components of SZB.

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SZB supplementation could be employed as a gastric protective agent/additive for human health.

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Nineteen potential biomarkers were identified as the potential biomarkers contributed to the gastric protective effect of SZB.

Supercritical carbon-dioxide (SC-CO₂) is a promising two-phase technology for flavor components (volatile oil and alkylamides) extract from Zanthoxylum bungeanum pericarp. However, the gastric protective effect of SC-CO₂ extract from Z. bungeanum (SZB) have not been systematically investigated. In this study, response surface methodology (RSM) was employed to optimize the yield of SZB, and the average yield of 11.07 % were obtained under optimal parameters (30 MPa, 43 °C and time 75 min). Here, limonene, linalool and hydroxy-α-sanshool were identified as the main compounds of SZB by GC–MS and UPLC-Q-Extractive Orbitrap/MS analysis. When the gastric protective effect of SZB (5, 10 and 20 mg/kg, p.o.) were evaluated, significant increase in body weight and organ indexes of rat, and decreased gastric lesion were observed. Furthermore, nineteen serum metabolites were regarded as the potential biomarkers for the gastric protective effect of SZB. Collectively, this study provides a comprehensive perspective into the chemical composition analysis and gastric protective effect of Z. bungeanum SC-CO₂ extract.

Functional validation of ZbFAD2 and ZbFAD3 in the alkylamide biosynthesis pathway from Zanthoxylum bungeanum Maxim

The spicy taste and medicinal properties of Zanthoxylum bungeanum are imparted by several alkylamides. Although most studies have focused on their isolation and identification, few have reported their biosynthesis pathways. Among the differentially expressed genes (DEGs) reported in the numerous varieties of Z. bungeanum, some might contribute to alkylamide biosynthesis. However, they are not yet functionally validated. The present study explored the function of two genes, ZbFAD2 and ZbFAD3, in the alkylamide biosynthesis pathway, and their stable and transient expression in Arabidopsis thaliana and Nicotiana benthamiana were also analyzed. As compared with the wild-type (WT), the fatty acid content analysis indicated that ZbFAD2-A. thaliana transgenic seeds had lower oleic acid and higher linoleic acid contents, while the ZbFAD3-A. thaliana transgenic seeds showed lower linoleic acid and higher α-linolenic acid levels. Moreover, hydroxy-α-sanshool, a major alkylamide, was considerably higher in the ZbFAD2-N. benthamiana transgenic plants (0.2167 ± 0.0026 mg/g) than in the WT (0.0875 ± 0.0049 mg/g), while it was lower in the ZbFAD3-N. benthamiana transgenic plants (0.0535 ± 0.0037 mg/g). These results suggest that both ZbFAD2 and ZbFAD3 are vital alkylamide biosynthesis enzymes in Z. bungeanum. Our study not only helps to scale up the alkylamide production, but also establishes the role of the uncharacterized genes.

Two new coumarins from branches of Zanthoxylum schinifolium

Two new coumarins (1-2) have been isolated from a methanol extract of Zanthoxylum schinifolium branches. The structures of compounds 1 and 2 have been elucidated as 6-isopentenyl -7-benzoyl-coumarin and 3-isopentenyl-7-benzoyl-coumarin based on extensive spectroscopic analysis, including IR, NMR, and MS. The inhibitory activity of compounds 1 and 2 against HeLa and HepG2 cell lines has been described.

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.

Storage Stability and Flavor Change of Marinated Pork

To evaluate the storage stability and flavor changes of marinated pork treated with chili and pepper essential oils, the contents of total sulfhydryl, malondialdehyde, total volatile base nitrogen (TVBN), Ca²⁺ATPase activity, and total viable counts of marinated pork were determined. Further, the non-volatile (umami, numb, and spicy) and volatile flavor compounds of marinated pork were analyzed. Based on the results, the chili and pepper essential oils had limited effects on the storage stability of marinated pork. However, these essential oils could inhibit the oxidation of lipids and proteins and reduce the number of microorganisms and TVBN in marinated pork within 6 days. The non-volatile flavors of the marinated pork decreased as the refrigeration time increased. It was concluded that the decomposition of umami-enhancing nucleotides (GMP, IMP, XMP), the number of flavor substances (hydroxyl-α-sanshool, hydroxyl-β-sanshool), and spicy (capsaicin) tasting compounds caused the decrease in non-volatile flavors.

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.

Synthesis of Bungeanool, Isobungeanool, Dihydrobungeanool, Tetrahydrobungeanool, Hazaleamide, Lanyuamide III, and Analogues

The bungeanools are a family of alkamide natural products isolated from the pericarps of Zanthoxylum bungeanum (Sichuan pepper), and they are structurally related to the sanshools. While the sanshools, especially hydroxy-α-sanshool, have been studied in a variety of contexts, research regarding the bungeanools has been much more limited. To facilitate their study, we have developed stereoselective syntheses of all four members of this family of compounds by using flexible routes that are also amenable to the synthesis of analogues. The key transformation in the syntheses was the stereoselective triphenylphosphine/phenol-catalyzed isomerization of an alkynoate to the corresponding conjugated E,E-dienoate.

Interactions between Phenols and Alkylamides of Sichuan Pepper (Zanthoxylum Genus) in α-Glucosidase Inhibition: A Structural Mechanism Analysis

The phenols and alkylamides in 26 varieties of Zanthoxylum pericarps (ZP) were comparatively identified, and the contribution of these key components to the inhibition of in vitro α-glucosidase (α-Glu) was confirmed using principal component analysis (PCA) and ingredient recombination models. Additionally, spectrophotometric assays, nuclear magnetic resonance (NMR), and molecular docking (MD) were employed to characterize the interactions among key components in ZP when exposed to α-Glu. Four phenols and hydroxy-α-sanshool (α-SOH), which were recognized as main ingredients, presented an antagonistic effect in the inhibition of α-Glu. ¹H NMR demonstrated chemical shifts of certain hydrogens in the B phenolic ring and tetraenyl group, indicating a possible p-π conjugation between phenols and α-SOH. In addition, using MD analysis, the phenol-binding sites were observed to be negatively affected when α-SOH initially interacted with α-Glu. The combined results of the NMR and MD clarified the structural mechanism behind phenol/α-SOH antagonistic behavior in α-Glu inhibition.

Ultrasound-assisted enzymatic extraction of hydroxy-sanshool compounds from the hydrodistillation residue of two Sichuan peppers: optimization, quantification and pungent taste contribution evaluation

Hydroxy-sanshool compounds were extracted from the hydrodistillation residue of Z. bungeanum Maxim. pericarp (ZBM) and Z. armatum DC. pericarp (ZADC) by using ethanol–water extraction and extractions assisted with (i) enzymes, (ii) ultrasound, and (iii) enzymes and ultrasound. The yields of the hydroxy-sanshool extracts under these four extraction conditions were calculated and compared. The ultrasound-assisted enzymatic extraction was then optimized based on a Box–Behnken design. Furthermore, five hydroxy-sanshool compounds in the extracts were quantified and their pungent taste contribution value (PCV) was calculated. Oral sensory evaluation was finally performed. Compared with that of the hydroxy-sanshool extracted with ethanol–water, the yields of the samples from the extraction assisted with enzymes, ultrasound, and enzymes and ultrasound increased by 4.2–7.6%, 9.3–9.8%, and 21.5–26.2%, respectively. A maximum yield of 7.87% (w/w) was achieved by using ultrasound-assisted enzymatic extraction under the optimal conditions: 3.1% (w/w) amount of enzyme, an incubation temperature of 50.3 °C, and an ultrasound irradiation power of 207 W. The PCV of hydroxy-α-sanshool, hydroxy-β-sanshool, hydroxy-γ-sanshool, hydroxy-ε-sanshool, and hydroxy-γ-isosanshool was 1153, 447, 461, 139, and 51 ml g⁻¹ for the ZBM extract, respectively, while the PCV of these five hydroxyl-sanshools was 659 ml g⁻¹, 575 ml g⁻¹, not detected, 119 ml g⁻¹, and not detected for the ZADC extract, respectively. Tingling and salivation were the main taste sensations of ZBM, whereas numbing and tingling sensations were dominant in ZADC.

Hydroxy-sanshool compounds were extracted from the hydrodistillation residue of Z. bungeanum Maxim. pericarp and Z. armatum DC. pericarp by using ethanol–water extraction and extractions assisted with (i) enzymes, (ii) ultrasound, and (iii) enzymes and ultrasound.

The relationship between alkylamide compound content and pungency intensity of Zanthoxylum bungeanum based on sensory evaluation and ultra-performance liquid chromatography-mass spectrometry/ mass spectrometry (UPLC-MS/MS) analysis

BACKGROUND

Zanthoxylum bungeanum originating in different places varies in alkylamide content and pungency intensity.

RESULTS

The pungency intensity of 19 Zanthoxylum bungeanum samples was first determined with Scoville pungency units (SPUs). The SPUs were found to range from 3.80E + 04 to 5.40E + 05. The chemical compositions and contents were measured next, using the ultra-performance liquid chromatography-mass spectrometry/ mass spectrometry (UPLC-MS/MS) method. The total alkylamide content ranged from 9.83 ± 0.15 to 89.98 ± 1.35 g kg^-1 . Hydroxy-ϵ-sanshool, hydroxy-α-sanshool, hydroxy-β-sanshool, hydroxy-γ-sanshool, bungeanool, and isobungeanool were found to be the key pungent compounds, ranging in proportion from 92.65% to 97.69%. The relationship between alkymide compound content and pungency intensity was also analyzed by ridge regression, and it was found that the β values of independent variables were stable when k was more than 0.6. The regression coefficients of hydroxy-ϵ-sanshool, hydroxy-α-sanshool, hydroxy-β-sanshool, hydroxy-γ-sanshool, bungeanool, isobungeanool, and other alkylamides were 0.105, 0.177, 0.386, -0.166, -0.006, 0.005, and -0.018, respectively.

CONCLUSION

Hydroxy- sanshool compounds were important in determinant the pungency intensity of Z. bungeanum. Knowledge of the relationship between alkymide compound content and pungency intensity will assist in the creation of new methods to determine pungency intensity and provide a scientific basis for flavor design, development of pungent food products, and consumer choice evaluations. © 2018 Society of Chemical Industry.

Comparison of volatile components in fresh and dried Zanthoxylum bungeanum Maxim

Fresh and dried Zanthoxylum bungeanum Maxim volatiles of two main cultivars including Dahongpao and Meihuajiao, were determined through GC-MS and compared. In all the tested samples, linalool, d-limonene, eucalyptol, 3-nonanone, and β-myrcene were identified as the five predominant components. The percentages of these components in fresh Dahongpao were 23.89%, 21.04%, 7.46%, 5.63% and 5.87%, respectively. Similar percentages, 27.28%, 17.62%, 6.39%, 1.66% and 7.8%, were found in dried Dahongpao. In general, the contents of linalool and β-myrcene in dried Dahongpao and Meihuajiao were slightly higher than those in fresh samples, whereas the contents of d-limonene, eucalyptol, and 3-nonanone were lower. Partial least squares discriminant analysis results showed that the two cultivars could be clearly differentiated based on volatiles, whereas, the fresh and dried Zanthoxylum bungeanum Maxim samples could not. This demonstrated that the drying process had no significant effect on the volatiles.

Polyunsaturated fatty acid amides from the Zanthoxylum genus – from culinary curiosities to probes for chemical biology

A critical and comprehensive review of the discovery, synthesis, and biological activities of alkamides isolated from Zanthoxylum plants and synthetic derivatives thereof.

Chemical Composition of Essential Oils from SixZanthoxylumSpecies and Their Repellent Activities against Two Stored-Product Insects

The objective of this study was to analyze six essential oils fromZanthoxylumgenus (family Rutaceae) in China and evaluate their repellent activities againstTribolium castaneumandLasioderma serricorneadults. Six essential oils fromZanthoxylumgenus, includingZ. armatum,Z. dimorphophyllum,Z. dimorphophyllumvar.spinifolium,Z. piasezkii,Z. stenophyllum,andZ. dissitum,were obtained by hydrodistillation and their yields were ranging from 0.02% to 0.53%. Totally, there were 39 chemical components revealed by GC-MS. Among them, some components with high relative content existed in more than threeZanthoxylumspecies. For instance, bothδ-cadinene (1.21%–17.15%) and spathulenol (0.36%–10.19%) appeared in essential oils ofZ. dimorphophyllum,Z. piasezkii,Z. stenophyllum,andZ. dissitumwhich were found to have higher content of sesquiterpenoids. The repellent activities of six essential oil samples againstT. castaneumandL. serricorneadults were investigated for the first time. Data demonstrated that sixZanthoxylumspecies had much stronger repellent activities againstT. castaneumthanL. serricorneadults, especially in 2 hours after exposure. The results indicate that these six essential oils fromZanthoxylumhave significant potential to be developed into natural repellents to control insects in grains, food, and traditional Chinese medicinal materials.

Isobutylhydroxyamides from Zanthoxylum bungeanum and Their Suppression of NO Production

Four new unsaturated aliphatic acid amides, named zanthoamides A–D (1–4), and eight known ones—tetrahydrobungeanool (5), ZP-amide A (6), ZP-amide B (7), ZP-amide C (8), ZP-amide D (9), ZP-amide E (10), bugeanumamide A (11), and (2E,7E,9E)-N-(2-hydroxy-2-methylpropyl)-6,11-dioxo-2,7,9-dodecatrienamide (12)—were isolated from the pericarps of Zanthoxylum bungeanum. The structures of these compounds were elucidated by extensive use of spectroscopic methods, including HRESIMS, 1D and 2D NMR analyses and comparison with previously reported data. Compound 4 contained a rare C₆ fatty acid unit with an acetal group. Results revealed that compounds 1, 5, 6, and 12 showed inhibitory effects on nitric oxide (NO) production in LPS-stimulated RAW 264.7 macrophages, with IC₅₀ values of 48.7 ± 0.32, 27.1 ± 1.15, 49.8 ± 0.38, and 39.4 ± 0.63 µM, respectively, while the other compounds were inactive (IC₅₀ > 60 μM). They could contribute to the anti-inflammatory effects of Z. bungeanum by suppression of NO production.

Characterization of isobutylhydroxyamides with NGF-potentiating activity from Zanthoxylum bungeanum

Eight isobutylhydroxyamides, including three new (1-3), qinbunamides A-C, and five known sanshools (4-8), ZP-amide A (4), ZP-amide B (5), ZP-amide E (6), ZP-amide C (7), and ZP-amide D (8), were isolated from the pericarps of cultivated Zanthoxylum bungeanum Maxim, cultivated in Qinling mountain area, Shaanxi, China. The structures of all compounds were determined on the basis of spectroscopic techniques, including 1D and 2D NMR analysis and comparison with previously reported data. Compounds 1 and 2 are the first example of isobutylhydroxyamides containing an ethoxy group, and compound 3 is a rare C11 fatty acid-containing sanshool existing in genus Zanthoxylum. The tested compounds enhanced nerve growth factor (NGF)-mediated neurite outgrowth (neurotrophic activity) in rat pheochromocytoma (PC12) cells, but were inactive in the inhibitory effects on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and growth of HCT116 cells at concentrations of 50μM.

Hypoglycemic effects of Zanthoxylum alkylamides by enhancing glucose metabolism and ameliorating pancreatic dysfunction in streptozotocin-induced diabetic rats

Alkylamides extracted from Zanthoxylum, a seasoning spice and folk medicine, exhibited hypoglycemic properties by enhancing glucose metabolism and ameliorating pancreatic dysfunction.