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Currently, little is known about the characteristics of polyphenol oxidase from wheat bran, which is closely linked to the browning of wheat product. The wheat PPO was purified by ammonium sulfate precipitation, DEAE-Sepharose ion-exchange column, and Superdex G-75 chromatography column. Purified wheat PPO activity was 11.05-fold higher, its specific activity was 1365.12 U/mg, and its yield was 8.46%. SDS-PAGE showed that the molecular weight of wheat PPO was approximately 21 kDa. Its optimal pH and temperature were 6.5 and 35 °C for catechol as substrate, respectively. Twelve phenolic substrates from wheat and green tea were used for analyzing the substrate specificity. Wheat PPO showed the highest affinity to catechol due to its maximum Vmax (517.55 U·mL-1·min-1) and low Km (6.36 mM) values. Docking analysis revealed strong affinities between catechol, gallic acid, EGCG, and EC with binding energies of -5.28 kcal/mol, -4.65 kcal/mol, -4.21 kcal/mol, and -5.62 kcal/mol, respectively, for PPO. Sodium sulfite, ascorbic acid, and sodium bisulfite dramatically inhibited wheat PPO activity. Cu2+ and Ca2+ at 10 mM were considered potent activators and inhibitors for wheat PPO, respectively. This report provides a theoretical basis for controlling the enzymatic browning of wheat products fortified with green tea.
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Catecol Oxidase , Fibras na Dieta , Catecol Oxidase/química , Fibras na Dieta/análise , Concentração de Íons de Hidrogênio , Cinética , Proteínas de Plantas/metabolismo , Catecóis/análise , Especificidade por Substrato , CháRESUMO
BACKGROUND: Several researchers have reported that the texture of fries is affected by the fatty acid composition of oil, although the mechanism of this effect is not clear. In this regard, fries were fried in refined rapeseed oil and fully hydrogenated rapeseed oil with diverse proportions (0%, 20%, 40%, 60%, 80% and 100%) and were analyzed based on the content of moisture and oil, texture, thermal properties, crystalline properties and microstructure. RESULTS: The outcomes presented that fries fried in fully hydrogenated oil had less oil absorption and moisture loss than those fried in refined oil. The results from the texture analyzer, differential scanning calorimetry and X-ray diffraction showed that hardness, enthalpy and relative crystallinity increased with an increase in the proportion of fully hydrogenated oil. However, the peaks of starch-lipid complexes were hardly observed during frying. Furthermore, scanning electron microscopy results displayed that some physically trapped fat was observed in fries fried in mixed hydrogenated oil. Stereomicroscope images showed that the crust thickness of the fries increased slightly with an increase in the proportion of fully hydrogenated oil. CONCLUSION: Overall, the upsurge in crust thickness and oil crystals was responsible for an increase in the hardness of the fries. This indicated that the texture of fries can be manipulated by altering the fatty acid composition of the oil. © 2021 Society of Chemical Industry.
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Ácidos Graxos , Solanum tuberosum , Culinária/métodos , Óleo de Brassica napus , Solanum tuberosum/química , AmidoRESUMO
In this study, phosphorylated derivatives of long-chain inulin with different substitution degrees were prepared. The synthesized samples were named PFXL-1, PFXL-2, PFXL-3, and PFXL-4 according to their degree of substitution (from low to high). The structures of FXL and PFXL were characterized by infrared spectroscopy and nuclear magnetic resonance spectroscopy, and the results indicated the successful introduction of phosphate groups. FXL and PFXL were composed of two types of sugar, fructose and glucose, with a molar ratio of 0.977:0.023. The SEM results showed that phosphorylation changed the morphology of FXL from an irregular mass to small spherical aggregates. The XRD pattern showed that the crystallinity was reduced by the introduction of phosphate groups. The Mw of FXL was 2649 g/mol, and the Mw of PFXL-4 increased the most (2965 g/mol). Additionally, PFXL was more stable and uniform, and the absolute value of the PFXL potential reached 7.83 mV. Phosphorylation decreased the weight loss rate of FXL and improved the viscoelastic properties and antioxidant activity of FXL. This study presents a method for the modification of FXL, demonstrating that phosphorylation can enhance its physicochemical properties and physiological activity and suggesting its potential as a functional food and quality modifier.
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Antioxidantes , Inulina , Antioxidantes/farmacologia , Antioxidantes/química , Inulina/química , Espectrofotometria Infravermelho , Espectroscopia de Ressonância Magnética , FosfatosRESUMO
The aim of this study was to investigate the rheological properties, particle size distribution, color change, and stability of lily juice under different ultrasonic treatment conditions (152 W, 304 W, 456 W, 608 W, and 760 W). The results showed that the lily juice exhibited non-Newtonian shear thinning behavior, and the viscosity decreased with the increase in ultrasonic power. Under ultrasonic treatment conditions, there was no significant change in the pH value and zeta potential value of the samples. The content of cloudy value and total soluble solids (TSS) increased gradually. However, both the sedimentation components and centrifugal sedimentation rate showed a downward trend and an asymptotic behavior. In addition, high-power ultrasound changed the color index (L* value decreased, a* value increased), tissue structure, and particle distribution of the sample, and small particles increased significantly. To sum up, ultrasonic treatment has great potential in improving the physical properties and suspension stability of lily juice.
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The COVID-19 pandemic has become a global public health crisis, causing significant morbidity and mortality worldwide. As an early response, different lockdowns were imposed in the UK (and the world) to limit the spread of the disease. Although effective, these measures profoundly impacted mobility patterns across cities, significantly reducing the number of people commuting to work or travelling for leisure. As different governments introduced massive vaccination programs to tackle the pandemic, cities have significantly but slowly increased human mobility, enabling the resumption of travel, work, and social activities. Nevertheless, how much can this return to normal mobility patterns be attributed to vaccines? In this study, we answer this question using a statistical approach, analysing two different open urban mobility datasets to quantify the effect vaccination rollouts have had on increased human activities.
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A self-derivation strategy using conductive substrates is used to prepare one-piece highly efficient bifunctional electrodes, where the chosen substrate acts as both an active catalyst precursor and a conductive carrier. Here, a bifunctional catalyst, porous NiS/Ni9S8/NF-2 nanorods, was synthesized by low-temperature vulcanization after an oxalic acid etching process. To reach a current density of 10 mA cm-2, NiS/Ni9S8/NF-2 requires only a tiny overpotential of 115 mV for the HER and 176 mV for the OER, and demonstrates sustained activity for 100 hours with almost any degradation. The substrate self-derived NiS/Ni9S8/NF-2 catalyst for overall water splitting requires only a small voltage of 1.52 V to deliver 10 mA cm-2 with excellent stability. Experimental results show that the heterostructured electrocatalysts impart good catalytic properties of NiS/Ni9S8/NF-2 by modulating the electronic structure and promoting the reconstruction process from sulfides to hydroxides. This work demonstrates the success of the substrate self-derivation strategy to achieve high catalytic activity and provide a new autogenous growth technique for electrode fabrication.
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Person re-identification (Re-ID) has become a hot research topic due to its widespread applications. Conducting person Re-ID in video sequences is a practical requirement, in which the crucial challenge is how to pursue a robust video representation based on spatial and temporal features. However, most of the previous methods only consider how to integrate part-level features in the spatio-temporal range, while how to model and generate the part-correlations is little exploited. In this paper, we propose a skeleton-based dynamic hypergraph framework, namely Skeletal Temporal Dynamic Hypergraph Neural Network (ST-DHGNN) for person Re-ID, which resorts to modeling the high-order correlations among various body parts based on a time series of skeletal information. Specifically, multi-shape and multi-scale patches are heuristically cropped from feature maps, constituting spatial representations in different frames. A joint-centered hypergraph and a bone-centered hypergraph are constructed in parallel from multiple body parts (i.e., head, trunk, and legs) with spatio-temporal multi-granularity in the entire video sequence, in which the graph vertices representing regional features and hyperedges denoting relationships. Dynamic hypergraph propagation containing the re-planning module and the hyperedge elimination module is proposed to better integrate features among vertices. Feature aggregation and attention mechanisms are also adopted to obtain a better video representation for person Re-ID. Experiments show that the proposed method performs significantly better than the state-of-the-art on three video-based person Re-ID datasets, including iLIDS-VID, PRID-2011, and MARS.
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Potato flour (PF) is rich in health-promoting compounds that can improve the nutritional benefits of food products after blending with wheat flour. However, the incorporation of PF may influence the processing characteristics of mixed powders and the quality properties of products. In this study, the physicochemical properties, processing characteristics, and structures of mixed powders and their corresponding doughs with different PF content (0%, 10%, 20%, 30%, 40%, 60%, 80%, and 100%) were investigated. The addition of PF dramatically increased the fiber content from 0.09 to 1.10 g·kg-1 but diluted the protein in wheat flour. The peak and final viscosity of mixed powders decreased (from 5111.00 to 1806.33 cP and 5195.33 to 2135.33 cP, respectively) with an increase in PF fraction. The incorporation of PF significantly increased gelatinization temperature. The rapidly digestible starch decreased from 30.48% to 19.67%, and resistant starch increased from 16.93% to 41.84% when the PF content increased from 0% to 100%. The water absorption, stability time, and development time decreased with an increase in PF levels. The G' and Gâ³ of the dough decreased as the addition amount of PF increased, while tan δ presented a complex change tendency. Due to the decrease in protein content in the mixed powders, the addition of PF in wheat flour notably decreased the Hm values of doughs and total carbon dioxide volume produced during fermentation. Additionally, the SH and S-S contents decreased with an increase in PF fraction. Scanning electron microscopy results showed that when the PF content reached up to 80%, a poor and discontinuous gluten framework was formed in the dough. Results showed that PF affected the processing characteristics and gluten structures of wheat dough and was related to the interaction or competition for water molecules between protein and starch, as well as potato starch and wheat starch. Thus, the results of the present study can provide insights into the optimal level of addition of PF during the development of potato-based food products.
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Staphylococcus aureus is a common foodborne pathogen which can form biofilms to help them resist to antimicrobials. It brings great harm to human health. Punicalagin has good antimicrobial activities against S. aureus, but its effect on biofilm formation has not been clearly illustrated. The aim of this study was to explore the antibiofilm effects of punicalagin against S. aureus. Results showed that punicalagin did not significantly interfere with the growth of S. aureus at the concentrations of 1/64 MIC to 1/16 MIC. The biomass and metabolic activity of biofilms were significantly reduced when exposed to sub-inhibitory concentrations of punicalagin. The number of viable cells in the biofilms was also decreased after punicalagin treatment. Scanning electron microscopy and confocal laser scanning microscopy images confirmed that punicalagin damaged the structure of biofilms. The antibiofilm mechanism was partly due to the modification of the cell surface which led to the reduction of cell surface hydrophobicity. These findings suggest that punicalagin has the potential to be developed as an alternative to control S. aureus biofilms.
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RATIONALE AND OBJECTIVES: Adrenal venous sampling (AVS) is the primary method for differentiating between primary aldosterone (PA) subtypes. The aim of study is to develop prediction models for subtyping of patients with PA using computed tomography (CT) radiomics and clinicobiochemical characteristics associated with PA. MATERIALS AND METHODS: This study retrospectively enrolled 158 patients with PA who underwent AVS between January 2014 and March 2021. Neural network machine learning models were developed using a two-stage analysis of triple-phase abdominal CT and clinicobiochemical characteristics. In the first stage, the models were constructed to classify unilateral or bilateral PA; in the second stage, they were designed to determine the predominant side in patients with unilateral PA. The final proposed model combined the best-performing models from both stages. The model's performance was evaluated using repeated stratified five-fold cross-validation. We employed paired t-tests to compare its performance with the conventional imaging evaluations made by radiologists, which categorize patients as either having bilateral PA or unilateral PA on one side. RESULTS: In the first stage, the integrated model that combines CT radiomic and clinicobiochemical characteristics exhibited the highest performance, surpassing both the radiomic-alone and clinicobiochemical-alone models. It achieved an accuracy and F1 score of 80.6% ± 3.0% and 74.8% ± 5.2% (area under the receiver operating curve [AUC] = 0.778 ± 0.050). In the second stage, the accuracy and F1 score of the radiomic-based model were 88% ± 4.9% and 81.9% ± 6.2% (AUC=0.831 ± 0.087). The proposed model achieved an accuracy and F1 score of 77.5% ± 3.9% and 70.5% ± 7.1% (AUC=0.771 ± 0.046) in subtype diagnosis and lateralization, surpassing the accuracy and F1 score achieved by radiologists' evaluation (p < .05). CONCLUSION: The proposed machine learning model can predict the subtypes and lateralization of PA. It yields superior results compared to conventional imaging evaluation and has potential to supplement the diagnostic process in PA.
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Highly efficient generation and arbitrary manipulation of spin-polarized terahertz (THz) radiation will enable chiral lightwave driven quantum nonequilibrium state regulation, induce new electronic structures, consequently provide a powerful experimental tool for investigation of nonlinear THz optics and extreme THz science and applications. THz circular dichromic spectroscopy, ultrafast electron bunch manipulation, as well as THz imaging, sensing, and telecommunication, also need chiral THz waves. Here we review optical generation of circularly-polarized THz radiation but focus on recently emerged polarization tunable spintronic THz emission techniques, which possess many advantages of ultra-broadband, high efficiency, low cost, easy for integration and so on. We believe that chiral THz sources based on the combination of electron spin, ultrafast optical techniques and material structure engineering will accelerate the development of THz science and applications.
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The processing parameters have a crucial influence on the stability and sensory quality of beverages. The focus of this study is to observe the rheological behavior, particle size distribution, stability, color change, and sensory evaluation of chestnut lily beverages (CLB) at different rotational speeds (0~20,000 rpm) using a high-shear homogeneous disperser. The CLB system exhibited non-Newtonian shear-thinning behavior. As the homogenization speed increased (0~12,000 rpm), the viscosity increased (0.002~0.059 Pa.s). However, when the rotational speed shear continued to increase (12,000~20,000 rpm), the viscosity decreased slightly (0.035~0.027 Pa.s). Under all homogeneous conditions, the turbidity and precipitation fractions were the lowest when the rotational speed was 12,000 rpm: the sedimentation index was lowest at this point (2.87%), and the relative turbidity value of CLB was largest at this point (80.29%). The average beverage particle diameter and ascorbic acid content showed a downward trend at the homogenization speed from 0 to 20,000 rpm, whereas the total soluble solids (TSS) content followed the opposite trend. The results show that these physical properties can be correlated with different rotational speeds of homogenization. This study explained the effect of homogenization speed on CLB properties, which needs to be considered in beverage processing, where high-speed shear homogenization can serve as a promising technique.
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We evaluated the effects of ultrasound (US) and ultrasound combined with nisin (NUS) treatments on the properties of chestnut lily beverages (CLB) using conventional thermal pasteurisation (TP) as a control. After CLB samples were treated with US and NUS for 20, 40, or 60 min, the polyphenol oxidase activity (PPO), microbial inactivation effect, colour, pH value, total phenolic content, and antioxidant capacity of the CLB were observed. It was found that the inactivation rate of PPO in CLB after NUS treatment was higher than that in the US, indicating that NUS treatment aggravated PPO inactivation. Treatment time was important in the inactivation of microorganisms by US and NUS; NUS had a lethal synergistic lethal effect on microorganisms in CLB and when compared with US, NUS reduced changes in the CLB colour value. Notably, the total phenolic content and antioxidant capacity of the US- and NUS-treated CLB significantly increased relative to the TP group. These results that suggest NUS has a potential application value in the development of CLB because it reduces the risk of microorganism contamination and helps improve the quality of CLB. This study provides technical support and a theoretical basis for the improved production of CLB.
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Future information technologies for low-dissipation quantum computation, high-speed storage, and on-chip communication applications require the development of atomically thin, ultracompact, and ultrafast spintronic devices in which information is encoded, stored, and processed using electron spin. Exploring low-dimensional magnetic materials, designing novel heterostructures, and generating and controlling ultrafast electron spin in 2D magnetism at room temperature, preferably in the unprecedented terahertz (THz) regime, is in high demand. Using THz emission spectroscopy driven by femtosecond laser pulses, optical THz spin-current bursts at room temperature in the 2D van der Waals ferromagnetic Fe3 GeTe2 (FGT) integrated with Bi2 Te3 as a topological insulator are successfully realized. The symmetry of the THz radiation is effectively controlled by the optical pumping incidence and external magnetic field directions, indicating that the THz generation mechanism is the inverse Edelstein effect contributed spin-to-charge conversion. Thickness-, temperature-, and structure-dependent nontrivial THz transients reveal that topology-enhanced interlayer exchange coupling increases the FGT Curie temperature to room temperature, which provides an effective approach for engineering THz spin-current pulses. These results contribute to the goal of all-optical generation, manipulation, and detection of ultrafast THz spin currents in room-temperature 2D magnetism, accelerating the development of atomically thin high-speed spintronic devices.
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Recently, ferromagnetic-heterostructure spintronic terahertz (THz) emitters have been recognized as one of the most promising candidates for next-generation THz sources, owing to their peculiarities of high efficiency, high stability, low cost, ultrabroad bandwidth, controllable polarization, and high scalability. Despite the substantial efforts, they rely on external magnetic fields to initiate the spin-to-charge conversion, which hitherto greatly limits their proliferation as practical devices. Here, a unique antiferromagnetic-ferromagnetic (IrMn3 |Co20 Fe60 B20 ) heterostructure is innovated, and it is demonstrated that it can efficiently generate THz radiation without any external magnetic field. It is assigned to the exchange bias or interfacial exchange coupling effect and enhanced anisotropy. By precisely balancing the exchange bias effect and enhanced THz radiation efficiency, an optimized 5.6 nm-thick IrMn3 |Co20 Fe60 B20 |W trilayer heterostructure is successfully realized, yielding an intensity surpassing that of Pt|Co20 Fe60 B20 |W. Moreover, the intensity of THz emission is further boosted by togethering the trilayer sample and bilayer sample. Besides, the THz polarization may be flexibly controlled by rotating the sample azimuthal angle, manifesting sophisticated active THz field manipulation capability. The field-free coherent THz emission that is demonstrated here shines light on the development of spintronic THz optoelectronic devices.
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Purpose: To explore the types of leisure activities, the degree of activity involvement, and the relationship between leisure benefits in older adults in cities and towns in Northern Guangdong, China; to provide valuable references for formulating related policies on the leisure industry for relevant governing bodies and for gaining the optimal benefits for industry business people and leisure enthusiasts. Methods: After searching for a large amount of literature and expert consultations, a questionnaire on the leisure involvement and leisure benefits scale was constructed. The participants aged 60 years or older were recruited as the survey population. By using SPSS statistics 21.0, the raw and processed data in this study were analyzed and interpreted. Results: (1) The approach that the leisure involvement levels were divided into subjective and objective involvement levels to predict leisure benefits was more comprehensive and reliable than uni-level prediction. Among them, the overall leisure involvement level had a significant positive effect on the leisure benefits of leisure participants; the performance of the subjective involvement level to enhance the leisure benefits comprehensively surpassed the objective involvement level. (2) The effect of leisure involvement levels on leisure benefits was affected by the type of leisure, which was manifested as physiological and psychological leisure pleasure; the degree of leisure involvement had an inverted U-shaped relationship with its emotional leisure benefits. For individuals with physiological hedonistic leisure, the degree of leisure involvement had an inverted U-shaped relationship with its emotional, social, and self-realized leisure interests. (3) For individuals with psychological leisure, the degree of leisure involvement was positively U-shaped with its social and self-affirmed leisure benefits. However, this finding needs to be confirmed by further research. Conclusion: There are two types of linear and curvilinear relationships between the degree of leisure involvement and leisure benefits, which makes the connection between leisure involvement and leisure benefits deviate from the linearity in a particular situation and present an inverted U-shaped or positive U-shaped relationship, which shows, when the individuals are under- or over-volume leisure activities involvement, they will not create excellent leisure benefits.
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Atividades de Lazer , Idoso , China , Humanos , Inquéritos e QuestionáriosRESUMO
The oil absorption behavior of food during deep-frying greatly affects the quality of the final fried food. However, the research on oil absorption lacks comprehensive analysis and understanding. In this paper, the oil content, moisture content, oil distribution, and microstructure changes of fried potato sticks were explored via traditional method as well as advanced instruments, including low field nuclear magnetic resonance, magnetic resonance imaging, and scanning electron microscopy, and the differences and their corresponding relevance were analyzed and discussed. Results showed that the fatty acid composition of oils is highly related to their viscosity and surface tension, influencing the oil uptake of final products. Oil content was positively correlated with the peak height in the range of 20 ms-1000 ms (r2 = 0.99348 at 140 â, r2 = 0.99060 at 180 â). Oil distribution and microscopic morphology of the fried strips were affected by oil type and temperature.
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The production of French fries is a multistage process (blanching, pre-frying, freezing and final frying). Pre-stage processing can result in drastic changes related to the quality of the final product. In this study, we investigated the effect of multistage process on quality properties, water and oil distribution and microstructure of fries prepared with different oils. Results showed that freezing treatment had little effect on water and oil content, color and volumetric shrinkage of pre-fried fries. Final fried fries exhibited drastic changes involved in the content and status of water and oil, color, texture, volumetric shrinkage and microstructure compared with other processing stage. Besides, magnetic resonance imaging visualized a thicker crust in finish-fried fries. Among all the oils, fries fried in high-oleic sunflower oil showed the best mouthfeel. This will provide a theoretical guidance for food enterprise to produce high-quality French fries.
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Culinária , Solanum tuberosum , Óleos , Água , Qualidade da ÁguaRESUMO
The properties of moisture and starch in potatoes affect the quality and oil absorption of final fried products. In this study, changes in moisture state, starch properties, and micromorphology of potato strips pretreated by microwave heating (MH) and vacuum oven drying (VOD) were investigated using low-field nuclear magnetic resonance, magnetic resonance imaging (MRI), differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy (SEM) analyses. The influence of changes in these properties on the oil content and distribution of fried potato strips was analyzed. Results showed that the decreased moisture content and changed moisture state in the pretreated samples had a positive effect on reducing the oil content. The pregelatinized starch facilitated the formation of V-type starch-lipid complexes, which formed a protective layer to prevent oil absorption. Analysis of MRI and confocal laser scanning microscopy images confirmed this finding. SEM observation showed microstructural changes might have an effect on oil absorption and its results exhibited crusts of the MH-pretreated samples thickened after frying, and the internal pores and structures of the VOD-pretreated samples became small and dense, respectively; both changes negatively affected oil absorption. Results could help understand the oil absorption behavior of starch-based food during frying and provide a basis for improving the quality and controlling the final oil content of the product.
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Solanum tuberosum , Culinária , Calefação , Micro-Ondas , VácuoRESUMO
Herbaceous peony (HP) seed oil has been consumed in some regions of China, yet little information is available on its bioactive composition and antioxidant activity. This study aimed to evaluate the fatty acid compositions, micronutrients contents, and cellular antioxidant activity (CAA) of HP seed oil from five varieties. Results indicated that this oil had high percentages of monounsaturated (32.15 to 45.92%) and polyunsaturated fatty acids (58.65 to 61.95%), and the α-linolenic acid C18:3 was the highest in Fushao seed oil. Additionally, the high concentrations of tocopherol and phytosterol were found in all seed oils, and 10 individual polyphenols have been evaluated. Fushao seed oil had the highest polyphenols levels and showed higher CAA values. Both hierarchical cluster analysis and principal component analysis have been used to distinguish HP seed oil from different varieties. This information is valuable for the nutritional value and industrial interest of HP seed oil in China. PRACTICAL APPLICATION: This research showed that Herbaceous peony seed oil had higher levels of minor components and polyunsaturated fatty acids, especially, α-linolenic acid, and our results could also provide the theoretical foundation for the health benefits of Herbaceous peony seed oil as the vegetable oils. However, the variety of Herbaceous should be considered when extracting oil from Herbaceous peony seeds in the industry.