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NaY(WO4)2:Eu3+ phosphors were synthesized using high-temperature solid state method. The effects of Eu3+ doping concentrations on structure and photoluminescence properties of the powders were investigated. The results indicate that the pure NaY(WO4)2:Eu3+ phase can be produced by calcining at 800°C where Eu3+ doping does not alter the main phase structure. Eu3+ ions were successfully incorporated into the crystal lattice, replacing Y3+ at the B-site. This caused gradual shifts of the characteristic X-ray diffraction peaks to lower 2θ angles. Morphological characterization revealed that the sample particles had irregular polygonal shapes with sizes ranging from 100 to 300 nm. There was minimal variation in morphology among samples with different doping concentrations. The samples exhibited the characteristic spectral emission of Eu3+ and emitted red light at a wavelength of 616 nm when excited by 394 nm near-ultraviolet light. The luminescence intensity of the nanophosphor gradually increased with increasing Eu3+ doping concentration, reaching its maximum at a doping ratio of 0.6, followed by a decrease due to the concentration quenching. The quenching mechanism was analysed to be primarily dipole-dipole interaction, in accordance with the Dexter’s theory of doping concentration. The luminescence positions of the phosphors slightly changed with varying Eu3+ doping concentrations, and the colour coordinates closely matched the standard value of the red colour in the National Television Standards Committee, confirming the stability of the obtained powders as red phosphors.

The increase of carbon emission is the main driver of global warming, which has seriously threatened the sustainable development of human society and the balance of the ecosystem. This paper focuses on county-level cities within the Yellow River Basin. Using land use data, energy consumption data and nighttime light remote sensing data, carbon emissions resulting from land use are computed for from 2000 to 2020, and studies its spatiotemporal evolution characteristics and the influencing factors. The results indicate that: (1) From 2000 to 2020, the carbon emissions in the Yellow River Basin increased continuously, with forests and construction areas being the primary carbon sink and source, respectively. Significant variations existed in carbon emissions in different counties, exhibiting an "east-high, west-low" spatial distribution pattern, while the center of carbon emissions showed a tendency to migrate towards the northwest. (2) The intensity of carbon emissions from land use, along with land use structure, economic development level, and population size all influence carbon emissions, with economic development level having the most significant impact. Adjusting industrial structure can effectively restrain the growth of carbon emissions. The area of land occupied per unit of GDP in the secondary industry consistently inhibits carbon emissions. These research findings hold significant implications for scientifically formulating land use policies and promoting basinwide collaborative emissions reduction initiatives in the Yellow River Basin.

In this article, we study the evolution of immersed locally convex plane curves driven by anisotropic flow with inner normal velocity V=1αψ(x)καV=\frac{1}{\alpha }\psi \left(x){\kappa }^{\alpha } for α1\alpha \gt 1, where x∈[0,2mπ]x\in \left[0,2m\pi ] is the tangential angle at the point on evolving curves. For −1≤α1\alpha \gt 1, we show only type I singularity arises in the flow, and the rescaled flow has subsequential convergence, i.e. for any time sequence, there is a time subsequence along which the rescaled curvature of evolving curves converges to a limit function; furthermore, if the anisotropic function ψ\psi and the initial curve both have some symmetric structure, the subsequential convergence could be refined to be full-time convergence.

BACKGROUND The extractable state of soil heavy metal elements is an important index to measure their bioavailability, but its content changes with soil acid-base properties and other environmental conditions. When determining which method to use for the extractable state of soil heavy metal elements, there are more than 7 kinds of extraction reagents involved in relevant standard methods or technical specifications. These include hydrochloric acid of pH=5.8, 0.1mol/L hydrochloric acid, 0.43±0.02mol/L nitric acid, 0.11mol/L acetic acid, 1mol/L ammonium nitrate solution, 0.005mol/L DTPA leaching agent, 0.01mol/L calcium chloride solution. Different scholars have different research conclusions on different extractants. There is no systematic research report on extractants suitable for different soil types. OBJECTIVES To select and determine the general extractant suitable for the extractable state of heavy metal elements in soil with different acid-base properties. METHODS Using typical farming soil samples as the research objective, 7 kinds of extracting agent were used to extract 8 heavy metals (Cd, Ni, Cu, Zn, Cr, Pb, As and Hg). Inductively coupled plasma-mass spectrometry (ICP-MS) was used to determine Cd, Cr, Cu, Pb, Zn, Ni, whereas atomic fluorescence spectrometry (AFS) was used to determine As and Hg. The extraction rates of 7 kinds of extractants were compared, and the effects of soil acid and alkali properties on the extraction rate of heavy metal elements were studied. RESULTS Dilute acid solution had a strong ability of leaching heavy metals from soil, and it was not related to the acidity and alkalinity of the soil. Although the extraction ability of 1mol/L ammonium nitrate solution for cadmium indicated that the activity of cadmium in acidic soil was much higher than that in alkaline soil, its extraction rate of lead in alkaline soil was higher than that of cadmium. The extraction rate of DTPA extractant for soil heavy metal elements was significantly higher than that of 0.01mol/L calcium chloride solution, especially for lead, copper and zinc. Moreover, the extraction rate of DTPA extractant for soil heavy metal elements did not change significantly with soil acid-base properties. 0.01mol/L calcium chloride solution had the highest extraction rate of cadmium in soil, which was closely related to the acid-base properties of soil. CONCLUSIONS 0.01mol/L calcium chloride solution is an ideal general extractant for the extractable state of soil heavy metal elements.

Abstract Background Nattokinase is a fibrinolytic enzyme that has huge market value as a nutritional supplement for health promotion. In order to increase nattokinase yields, fermentation conditions, strains, cultivation media, and feeding strategies have been optimized. Nattokinase has been expressed using several heterologous expression systems. Pichia pastoris heterologous expression system was the alternative. Results This report aimed to express high levels of nattokinase from B. subtilis natto (NK-Bs) using a Pichia pastoris heterologous expression system and assess its fibrinolytic activity in vivo. Multicopy expression strains bearing 1–7 copies of the aprN gene were constructed. The expression level of the target protein reached a maximum at five copies of the target gene. However, multicopy expression strains were not stable in shake-flask or high-density fermentation, causing significant differences in the yield of the target protein among batches. Therefore, P. pastoris bearing a single copy of aprN was used in shake-flask and high-density fermentation. Target protein yield was 320 mg/L in shake-flask fermentation and approximately 9.5 g/L in high-density fermentation. The recombinant nattokinase showed high thermo- and pH-stability. The present study also demonstrated that recombinant NK-Bs had obvious thrombolytic activity. Conclusions This study suggests that the P. pastoris expression system is an ideal platform for the large-scale, low-cost preparation of nattokinase.

In the tumor microenvironment, tumor-infiltrating immune cells (TIICs) are a key component. Different types of TIICs play distinct roles. CD8+ T cells and natural killer (NK) cells could secrete soluble factors to hinder tumor cell growth, whereas regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) release inhibitory factors to promote tumor growth and progression. In the meantime, a growing body of evidence illustrates that the balance between pro- and anti-tumor responses of TIICs is associated with the prognosis in the tumor microenvironment. Therefore, in order to boost anti-tumor response and improve the clinical outcome of tumor patients, a variety of anti-tumor strategies for targeting TIICs based on their respective functions have been developed and obtained good treatment benefits, including mainly immune checkpoint blockade (ICB), adoptive cell therapies (ACT), chimeric antigen receptor (CAR) T cells, and various monoclonal antibodies. In recent years, the tumor-specific features of immune cells are further investigated by various methods, such as using single-cell RNA sequencing (scRNA-seq), and the results indicate that these cells have diverse phenotypes in different types of tumors and emerge inconsistent therapeutic responses. Hence, we concluded the recent advances in tumor-infiltrating immune cells, including functions, prognostic values, and various immunotherapy strategies for each immune cell in different tumors.

Based on the theory of the existing research of the project portfolio management, the paper analyzes the key factors of the project portfolio selection, and evaluates them using the fuzzy comprehensive evaluation method. Finally, the paper builds a project portfolio choice integer programming model based on 0/1 integer programming, which is based on the organizations strategies.

Rare earth elements (REEs) in ore have many different forms, mainly ion adsorption and mineral lattice types. The occurrence state of rare earth elements has a great impact on accurate analysis. In this study, the effects of different pretreatment methods in REEs analysis are discussed from the perspective of REEs occurrence states in ore. Four pretreatment methods including HCl-HNO3-HF-HClO4 under normal pressure (the open acid digestion), HCl-HNO3-HF-HClO4-H2SO4 under normal pressure (the open acid digestion, adding sulfuric acid), HF-HNO3 in confining pressure (the pressurized acid digestion) as well as NaOH-Na2O2 alkali fusion were conducted for REEs ores. 15 rare earth elements were determined by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). The results of the open HCl-HNO3-HF-HClO4 acid digestion for the two National Standard Substances (GBW 07161, GBW 07188) which are ion adsorption-type rare earth ores, are significantly lower, mostly 10%-20% lower than certified values. Meanwhile, the results from the pressurized acid digestion, the open HCl-HNO3-HF-HClO4-H2SO4 acid digestion and alkaline fusion are in agreement with certified values. For the two Baiyun Ebo REEs ore samples (SS-1 and BY-1) which are mineral lattice-type, results from all three acid digestions are lower than those from alkaline fusion. The results of the open HCl-HNO3-HF-HClO4 acid digestion are the lowest, approximately 20% lower than those from alkaline fusion, and results of the open HCl-HNO3-HF-HClO4-H2SO4 acid digestion and the pressurized acid digestion essentially are as low as approximately 5%-15%. In summary, for ion adsorption-type rare earth ores, the the open HCl-HNO3-HF-HClO4-H2SO4 acid digestion and pressurized acid digestion could replace the traditional alkaline fusion, while for mineral lattice-type rare earth ores, the most suitable pretreatment method is still alkaline fusion.

Rare earth elements (REEs) in ore have many different forms, mainly ion adsorption and mineral lattice types. The occurrence state of rare earth elements has a great impact on accurate analysis. In this study, the effects of different pretreatment methods in REEs analysis are discussed from the perspective of REEs occurrence states in ore. Four pretreatment methods including HCl-HNO3-HF-HClO4 under normal pressure (the open acid digestion), HCl-HNO3-HF-HClO4-H2SO4 under normal pressure (the open acid digestion, adding sulfuric acid), HF-HNO3 in confining pressure (the pressurized acid digestion) as well as NaOH-Na2O2 alkali fusion were conducted for REEs ores. 15 rare earth elements were determined by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). The results of the open HCl-HNO3-HF-HClO4 acid digestion for the two National Standard Substances (GBW 07161, GBW 07188) which are ion adsorption-type rare earth ores, are significantly lower, mostly 10%-20% lower than certified values. Meanwhile, the results from the pressurized acid digestion, the open HCl-HNO3-HF-HClO4-H2SO4 acid digestion and alkaline fusion are in agreement with certified values. For the two Baiyun Ebo REEs ore samples (SS-1 and BY-1) which are mineral lattice-type, results from all three acid digestions are lower than those from alkaline fusion. The results of the open HCl-HNO3-HF-HClO4 acid digestion are the lowest, approximately 20% lower than those from alkaline fusion, and results of the open HCl-HNO3-HF-HClO4-H2SO4 acid digestion and the pressurized acid digestion essentially are as low as approximately 5%-15%. In summary, for ion adsorption-type rare earth ores, the the open HCl-HNO3-HF-HClO4-H2SO4 acid digestion and pressurized acid digestion could replace the traditional alkaline fusion, while for mineral lattice-type rare earth ores, the most suitable pretreatment method is still alkaline fusion.

Based on the analysis of traditional state maintenance strategy and big data-based state maintenance strategy, this paper builds a transformer state duration simulation model based on Monte Carlo method and builds an annual cost model based on the running state of the transformer. Finally, a typical case is selected to simulate a time series of 8760 hours of transformer operation under two operational inspection strategies, and the annual cost is calculated separately. The example shows that the annual cost of the transformer is lower under the big data-based inspection strategy.

The Large High Altitude Air Shower Observatory (LHAASO) is a new hybrid array for very high energy gamma ray astronomy and cosmic ray physics. The KM2A array, one of the main parts of LHAASO, covers an area of 1.3 km2 to observe gamma rays above 10 TeV up to 1 PeV for many sources. A prototype with 1% the size of the whole KM2A has been in stable operation for more than two years. A Monte Carlo simulation program named G4KM2A was developed; based on this work, the trigger rate, hit multiplicity, angular and core reconstruction are compared with KM2A prototype data. Finally, the moon shadow with -6.5 significance was obtained. The G4KM2A simulation results are consistent with KM2A prototype data and can be used for the whole KM2A array in future.

A two-species model with variable population interactions and harvesting on one of the species is studied. Existence and stability of equilibria and existence of periodic solutions are established, existence of some bifurcation phenomena are analytically and numerically studied, explicit threshold values are computed to determine the kind of interaction ( mutualism, competition, host-parasite) between the two species. A brief discussion on the influence of the harvesting function on the dynamics of the model is also included.

Abstract Background Grass carp (Ctenopharyngodon idella) is one of the most economically important freshwater fish, but its production is often affected by diseases that cause serious economic losses. To date, no good breeding varieties have been obtained using the oriented cultivation technique. The ability to identify disease resistance genes in grass carp is important to cultivate disease-resistant varieties of grass carp. Results In this study, we constructed a non-normalized cDNA library of head kidney in grass carp, and, after clustering and assembly, we obtained 3,027 high-quality unigenes. Solexa sequencing was used to generate sequence tags from the transcriptomes of the head kidney in grass carp before and after grass carp reovirus (GCRV) infection. After processing, we obtained 22,144 tags that were differentially expressed by more than 2-fold between the uninfected and infected groups. 679 of the differentially expressed tags (3.1%) mapped to 483 of the unigenes (16.0%). The up-regulated and down-regulated unigenes were annotated using gene ontology terms; 16 were annotated as immune-related and 42 were of unknown function having no matches to any of the sequences in the databases that were used in the similarity searches. Semi-quantitative RT-PCR revealed four unknown unigenes that showed significant responses to the viral infection. Based on domain structure predictions, one of these sequences was found to encode a protein that contained two transmembrane domains and, therefore, may be a transmembrane protein. Here, we proposed that this novel unigene may encode a virus receptor or a protein that mediates the immune signalling pathway at the cell surface. Conclusion This study enriches the molecular basis data of grass carp and further confirms that, based on fish tissue-specific EST databases, transcriptome analysis is an effective route to discover novel functional genes.

Abstract Background Recent studies have shown that disruption of circadian rhythms is one of the tumor promoting factors which contribute to mammalian cancer development and progression, but very little is known about the molecular changes of circadian genes in colorectal carcinoma (CRC). Thus, in this study, changes in the expression of human Period2 (hPer2), one of the key circadian clock regulators, in CRC and its correlation with prognosis were investigated. Methods Immunohistochemical (IHC) staining and real-time PCR for hPer2 were performed for 38 CRC cases. Results IHC analysis detected positive staining for hPer2 in 81.6% (31/38) of CRC tissues and 97.4% (37/38) of surrounding non-cancerous tissues (P < 0.05). Most colorectal cells in non-cancerous tissues were homogeneously stained. In contrast, in the paired cancerous tissues, a heterogeneous pattern was found with a significant portion of cancer cells displaying negative or weak hPer2 staining. In over 60% cases (24/38), the staining for hPer2 was much stronger in non-cancerous cells than in the paired cancerous cells. Well-differentiated cancer cells are more likely to maintain hPer2 expression than poorly-differentiated ones. Furthermore, associations of decreased hPer2 levels with patients' age, histological grade, TNM stage and expression of nucleus proliferation related antigen: Ki67 were also detected (P < 0.05). Expression of hPer2 did not correlate with that of either p53 or C-erB-2. Similar to hPer2 protein expression, quantitative RT-PCR for hPer2 also showed decreased mRNA expression in CRC. Conclusion These results suggest a role for hPer2 in normal colorectal cell function and the potential deregulation of hPer2 expression in the development, invasion, and metastasis of CRC.

Abstract Background Gastric cancer is one of the most common cancers affecting East Asians, and MLH1 could play a critical role during tumorigenesis in this condition. Methods Samples from 236 Chinese patients suffering from gastric cancer were screened for MLH1 germline mutations. Carrier frequencies of the mutations were compared between gastric cancer patients and 240 cancer-free controls. Bioinformatic analysis was used to predict the effect of these mutations on protein function and mRNA splicing. Results Six MLH1 sequence alterations were identified in gastric cancer patients including two promoter region substitutions, -93G>A and -28A>G, and four missense mutations 649C>T (R217C), 655A>G (I219V), 1151T>A (V384D) and 2101C>A (Q701K). Compared with the MLH1 2101CC genotype, the 2101CA genotype was associated with a risk of gastric cancer (OR = 8.42, 95% CI = 1.04-68.06) in males. Furthermore, the MLH1 2101C>A mutant was predicted by in silico analysis to affect exon splicing ability. Immunohistochemistry of one index patient carrying the MLH1 2101C>A mutation demonstrated a loss of MLH1 protein and normal expression of MSH2 and E-cadherin. No significant differences were demonstrated between cases and controls for the other five MLH1 variants but the data indicated an ethnic difference in the frequency of these variations between Eastern Asians and Western populations. Conclusions An ethnic-specific MLH1 mutation spectrum occurred in Chinese gastric cancer patients. The MLH1 2101C>A mutation could be a marker for susceptibility to gastric cancer, particularly in males.

Abstract Background The human MutY homolog (hMYH), a DNA glycolsylase involved in the excision repair of oxidative DNA damage, is currently studied in colorectal cancer (CRC). We previously demonstrated a haplotype variant c.53C>T/c.74G>A of hMYH (T/A) increasing the risk for gastric cancer in Chinese. However, most investigations on correlation between hMYH and CRC are conducted in Western countries and the underlying mechanism has been poorly understood. Methods To determine whether the haplotype T/A variant of hMYH was related to colorectal carcinogenesis, we performed a case-control study in 138 colorectal cancer (CRC) patients and 343 healthy controls in a Chinese population. Furthermore, the C/G for wild-type, C/A or T/G for single base variant and T/A for haplotype variant hMYH cDNAs with a flag epitope tag were cloned into pcDNA3.1+ vector and transfected into cos-7 cell line. Their subcellular localizations were determined by immunofluorescence assay. Results It was found that the frequency of haplotype variant allele was statistically higher in CRC patients than that in controls (P = 0.02, odds ratio = 5.06, 95% confidence interval = 1.26 – 20.4). Similarly, significant difference of heterozygote frequency was indicated between the two groups (P = 0.019), while no homozygote was found. In addition, immunofluorescence analysis showed that hMYH protein with haplotype T/A variation presented in both nucleus and mitochondria, in contrast to the wild-type protein only converging in mitochondria. However, neither of the single missense mutations alone changed the protein subcelluar localization. Conclusion Although preliminarily, these results suggest that: the haplotype variant allele of hMYH leads to a missense protein, which partly affects the protein mitochondrial transportation and results as nuclear localization. This observation might be responsible for the increased susceptibility to cancers, including CRC, in Chinese.

为拓宽我国植物油料的开发利用途径，测定了薄壳山核桃、油茶、香榧、核桃、花生、油菜等6种植物种子的含油率及其油脂的总酚、生育酚含量和脂肪酸组成，并采用加速氧化试验对其油脂的氧化稳定性进行评价，探究了各项品质指标与氧化稳定性指标的相关性。结果表明：薄壳山核桃仁的含油率最高（73.07%），且其油脂的总酚含量最高（12.6 mg/kg），香榧籽油的生育酚总量最高（114.90 mg/100 g）；6种植物油中有5种共同脂肪酸，分别为棕榈酸、硬脂酸、油酸、亚油酸和花生烯酸；6种植物油中，薄壳山核桃油的氧化稳定性最强，其酸值、过氧化值、共轭二烯值、共轭三烯值、羰基值的变化幅度均较小，氧化诱导时间（OSI值）处于最高水平，核桃油的变化幅度较大；加速氧化过程中6种植物油的油酸、亚油酸、不饱和脂肪酸、饱和脂肪酸含量均无明显变化；油脂的OSI值与油酸、生育酚、总酚含量呈显著正相关，与亚油酸、亚麻酸含量呈显著负相关。综上，薄壳山核桃含油率高，薄壳山核桃油含有较高的总酚含量和较好的氧化稳定性，是一种优质的食用油，可作为营养保健油开发利用。In order to broaden the development and utilization of vegetable oilseeds in China, the oil contents of six vegetable oilseeds, including Carya illinoinensis (Wangenh.) K. Koch, Camellia oleifera Abel. seed, Torreya grandis seed, walnut, peanut and rapeseed, as well as the total phenol content, the tocopherol content and the fatty acid composition of their oils were determined, the oxidation stability of their oils was evaluated by the accelerated oxidation test, and the correlation between the quality indexes and the oxidation stability indexes was explored. The results showed that Carya illinoinensis (Wangenh.) K. Koch kernel had the highest oil content (73.07%) and the highest total phenol content in its oil (12.6 mg/kg), and total tocopherol content in Torreya grandis seed oil (114.90 mg/100 g) was the highest. There were five common fatty acids in the six vegetable oils, which were palmitic acid, stearic acid, oleic acid, linoleic acid, and arachidonic acid; and among the six vegetable oils, Carya illinoinensis (Wangenh.) K. Koch oil had the strongest oxidative stability, with small changes in acid value, peroxide value, conjugated diene value, conjugated triene value and carbonyl value, and the oxidation induction time (OSI value) was at the highest level, and larger change was found in walnut oil. There was no significant change in the contents of oleic acid, linoleic acid, unsaturated fatty acid and saturated fatty acid of the six vegetable oils during accelerated oxidation. There was a significant positive correlation between the OSI value of the oils and the contents of oleic acid, tocopherol and total phenol, and a significant negative correlation with the content of linoleic acid and linolenic acid. In conclusion, Carya illinoinensis (Wangenh.) K. Koch has high oil content, its oil has high total phenol content and high oxidative stability, so Carya illinoiensis (Wangenh.) K. Koch oil is a high-quality edible oil and can be developed and utilized as a nutritional and health care oil.

为优化薄壳山核桃油水酶法提取工艺，以薄壳山核桃仁为原料，采用水酶法提取油脂，筛选出水酶法提油的适宜酶制剂。在单因素试验基础上，采用正交试验研究料液比、加酶量、酶解温度、酶解时间和酶解pH对薄壳山核桃油提取率的影响，并对比了水酶法、压榨法和溶剂浸提法3种方法制取的薄壳山核桃油的品质。结果表明：蛋白酶为适宜的酶制剂；水酶法提取薄壳山核桃油的最佳工艺条件为料液比1∶ 4、加酶量2.5％、酶解温度55 ℃、酶解时间2.0 h、酶解pH 8，在此条件下薄壳山核桃油提取率为68.44％；薄壳山核桃油中含有7种主要脂肪酸，分别是棕榈酸、硬脂酸、油酸、亚油酸、α-亚麻酸、花生酸和顺-11-二十碳烯酸，不饱和脂肪酸含量高达90%以上，且以油酸和亚油酸为主，油酸含量高达70%以上，亚油酸含量在15%以上。3种制油方法中，水酶法制取的薄壳山核桃油具有较高的油酸、生育酚、总酚、β-谷甾醇和角鲨烯含量，油脂品质最好。水酶法是一种较为理想的核桃油提取方法。In order to optimize the process of aqueous enzymatic extraction of pecan oil, with the pecan nut as the raw material,the oil was extracted by aqueous enzymatic method and suitable enzyme was selected. On the basis of single factor experiment, the effects of solid-liquid ratio, enzyme dosage, enzymatic hydrolysis temperature, enzymatic hydrolysis time and enzymatic hydrolysis pH on the extraction rate of pecan oil were studied by orthogonal experiment, and the qualities of pecan oils produced by aqueous enzymatic method, pressing method and solvent extraction method were compared. The results showed that protease was selected as the suitable enzyme. The optimal conditions of aqueous enzymatic extraction of pecan oil were obtained as follows: solid-liquid ratio 1∶ 4, enzyme dosage 25%, enzymatic hydrolysis temperature 55 ℃, enzymatic hydrolysis time 2.0 h, and enzymatic hydrolysis pH 8. Under these conditions, the extraction rate of pecan oil was 68.44%. There were seven main fatty acids in pecan oil including palmitic acid, stearic acid, oleic acid, linoleic acid, α-linolenic acid, arachidic acid and cis-11-eicosenoic acid. The content of unsaturated fatty acids was higher than 90%, mainly oleic acid and linoleic acid. Oleic acid and linoleic acid accounted for more than 70% and 15% respectively. Comparing the three oil producing methods, the quality of pecan oil extracted by aqueous enzymatic method was the best with higher contents of oleic acid, tocopherol, total phenols, β-phytosterol and squalene. Aqueous enzymatic method is an ideal method to extract pecan oil.