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1.
Chemical Characteristics and Fatty Acid Profile of Foxtail Millet Bran Oil   总被引:3,自引:0,他引:3  
Chemical characteristics of a sample of foxtail millet bran and its oil, focusing on the approximate composition of foxtail millet bran and the fatty acid profile, physicochemical properties and tocopherol composition of foxtail millet bran oil, are presented in this work. The results indicate that the millet bran constituted 9.39 ± 0.17% crude oil, 12.48 ± 0.41% crude protein, and 51.69 ± 2.14% crude fiber. The specific gravity, refractive index, saponification value, and unsaponifiable matter content of millet bran oil were 0.9185 ± 0.0003 g/cm3 ( d2020 ) \left( {d_{20}^{20} } \right) , 1.4676 ± 0.0002 ( nD40 ) \left( {n_{D}^{40} } \right) , 186.29 ± 0.51 mg KOH/g, and 3.62 ± 0.19 g/100 g, respectively. The tocopherol content was 64.83 ± 0.83 mg/100 g oil, which consisted mainly of γ-tocopherol (48.79 ± 0.46 mg/100 g oil) and α-tocopherol (15.53 ± 0.31 mg/100 g oil). The millet bran oil was rich in linoleic acid (66.5%) and oleic acid (13.0%). The saturated fatty acids included palmitic acid (6.4%) and stearic acid (6.3%). The major fatty acid in the sn-2 position of the millet oil was linoleic acid (71.2%). The dominant triacylglycerols, calculated according to the 1,3-random-2-random hypothesis, were trilinoleate (LLL, 29.3%) and dilinoleoyl-monoolein (LLO, 17.2%). This work might be useful for developing applications for millet bran and its oil.  相似文献   

2.
Sterculia foetida oil contains cyclopropene fatty acids namely 8,9-methylene-heptadec-8-enoic acid (malvalic) and 9,10-methylene-octadec-9-enoic acid (sterculic) to an extent of 50–55%. The present study reports the preparation of biodiesel from S. foetida oil using sodium hydroxide as catalyst. The resultant biodiesel was evaluated for physico-chemical properties namely iodine value (72.6), free fatty acids (0.17%), phosphorous content (0 ppm), flash point (179 °C), cloud point (3 °C), pour point (3 °C), viscosity at 40 °C (4.72 cSt), oxidative stability at 110 °C (3.42 h), density (0.850 g/cm3 at 15 °C), and trace metals (Group I metals 0.21 ppm). The properties were compared with that of sunflower, soybean and rapeseed oil-based biodiesels and found to be comparable except for the pour point.  相似文献   

3.
Mungbean is a widely consumed legume globally. This study was carried out for detailed characterization of oils from mungbean seeds from four indigenously cultivated varieties, as very little information is available on the oil composition of mungbean seeds and inter-varietal variation in oil composition. The oil content was relatively low (2.1–2.7%). The investigated physiochemical parameters included refractive indices (RI) at 40 °C (1.4673–1.4698), relative density (0.9580–0.9618), iodine value (IV) (111.4 –117.1), saponification value (SV) (173.1–181.7 mg KOH/g) and unsaponifiable matter (UM) (13.8–15.01%). Phospholipids and triglycerides were the dominant lipid fractions followed by monoglycerides. Linoleic acid and oleic acid were the dominant fatty acids (FA). Characterization was also made by TLC. Tocopherol analysis demonstrated highest content of γ-tocopherol among its isomers, while α-tocotrienol was present in highest amount in all studied cultivars, among its isomers. Results from most of the parameters revealed significant (P ≤ 0.05) differences among the cultivars. The findings of the study reveal mungbean [Vigna radiata (L.) wilczek], to be a potentially valuable legume crop with comparable nutritional quality oil among all the cultivars.  相似文献   

4.
Zizyphi spinosi semen (ZSS) has been widely used for treatment of insomnia in oriental countries. The aim of this study is to characterize the fatty oil of ZSS obtained by supercritical fluid extraction in terms of chemical composition and physicochemical properties. The chemical composition, including fatty acids and unsaponifiable constituents, was analyzed by gas chromatography–mass spectrometer (GC–MS). The results revealed that 9-octadecenoic acid (43.38 ± 0.03%) and 9,12-octadecadienoic acid (40.58 ± 0.03%) were the main fatty acids, and β-sitosterol (37.39 ± 0.02%) and squalene (30.79 ± 0.01%) were the key unsaponifiables. Furthermore, four indexes were assayed according to Chinese Pharmacopeia (2005) to reflect the physicochemical properties of ZSS oil, their values being determined as follows: acid value (10.3 ± 0.1 mg KOH/g), peroxide value (0.05 ± 0.01 g/100 g), saponification value (194.4 ± 0.5 mg KOH/g) and iodine value (109.7 ± 0.8 g I/100 g). The basic information obtained provides data support for quality evaluation and efficacy research of ZSS oil, and suggests its prospects for development in pharmaceutical and food industries.  相似文献   

5.
The objective of this study was to investigate and compare fatty acids, tocopherols and sterols of kenaf seed oil extracted by supercritical carbon dioxide and traditional solvent methods. Fatty acids, tocopherols and sterols were determined in the extracted oils as functions of the pressure (400 bar, 600 bar), temperature (40 °C, 80 °C) and CO2 flow rate (25 g/min) using a 1-L extraction vessel. Gas chromatography was used to characterize fatty acids and sterols of the obtained oils while tocopherols were quantified by HPLC. No differences were found in the fatty acid compositions of the various oil extracts and the main components were found to be linoleic (38%), oleic (35%), palmitic (20%) and stearic acid (3%). Extraction of tocopherols using high pressure (600 bar/40 °C, 600 bar/80 °C) gave higher total tocopherols (88.20 and 85.57 mg/100 g oil, respectively) when compared with hexane extraction which gave yield of 62.38 mg/100 g oil. Extraction of kenaf seed oil using supercritical fluid extraction at high temperature (80 °C) gave higher amounts of sterols when compared with hexane extraction.  相似文献   

6.
A novel continuous subcritical n‐butane extraction technique for Camellia seed oil was explored. The fatty acid composition, physicochemical properties, and benzo[a]pyrene content of Camellia seed oil extracted using this subcritical technique were analyzed. Orthogonal experiment design (L9(34)) was adopted to optimize extraction conditions. At a temperature of 45 °C, a pressure of 0.5 MPa, a time of 50 min and a bulk density of 0.7 kg/L, an extraction yield of 99.12 ± 0.20 % was obtained. The major components of Camellia seed oil are oleic acid (73.12 ± 0.40 %), palmitic acid (10.38 ± 0.05 %), and linoleic acid (9.15 ± 0.03 %). Unsaturated fatty acids represent 83.78 ± 0.03 % of the total fatty acids present. Eight physicochemical indexes were assayed, namely, iodine value (83.00 ± 0.21 g I/100 g), saponification value (154.81 ± 2.00 mg KOH/g), freezing‐point (?8.00 ± 0.10 °C), unsaponifiable matter (5.00 ± 0.40 g/kg), smoke point (215.00 ± 1.00 °C), acid value (1.24 ± 0.03 mg KOH/g), refrigeration test (transparent, at 0 °C for 5.5 h), and refractive index (1.46 ± 0.06, at 25 °C). Benzo[a]pyrene was not detected in Camellia seed oil extracted by continuous subcritical n‐butane extraction. In comparison, the benzo[a]pyrene levels of crude Camellia seed oil extracted by hot press extraction and refined Camellia seed oil were measured at 26.55 ± 0.70 and 5.69 ± 0.04 μg/kg respectively.  相似文献   

7.
Flaxseed oil (FO) containing crawfish (Procambarus clarkii) astaxanthin (FOA) was evaluated for lipid oxidation and astaxanthin degradation. The FOA was analyzed for astaxanthin content, free fatty acids (FFA), peroxide value (PV), fatty acid methyl esters (FAMEs) profile, and color. The amount of extractable astaxanthin in the crawfish byproducts was 3.02 mg/100 g of crawfish byproducts. FOA and FO had a similar alpha-linolenic acid (ALA) content (on a weight% basis). The FO was lighter and more yellow in color than FOA. The oxidation rate of FOA was lower than that of FO. When FO and FOA were heated to 30 °C, both oils exhibited minimal lipid oxidation with increasing heating time, whereas FO, when heated to 40, 50, 60 °C, had a higher lipid oxidation rate than FOA with increasing the heating time from 0 to 4 h. Astaxanthin was an effective antioxidant agent in FO when it was heated from 30 to 60 °C. The degradation of astaxanthin in FOA could be described by first order reaction kinetics. Astaxanthin was stable in flaxseed oil at 30 and 40 °C, while its stability decreased significantly at 50 and 60 °C. The rate of astaxanthin degradation in FOA was significantly influenced by temperature.  相似文献   

8.
Four common beans (black, kidney, great northern, and pinto) were extracted with hexane and found to contain about 2% triacylglycerols. The fatty acids in these bean oils were mainly linolenic (41.7–46 wt%), linoleic (24.1–33.4 wt%), palmitic (10.7–12.7 wt%) and oleic (5.2–9.5 wt%). Because of the high levels of polyunsaturated fatty acids, the bean oils had iodine values between 174 and 177 g/100 g (compared to 130 g/100 g for soybean oil). Yet, the bean oils exhibited high oxidative stability due to the presence of high amounts of tocopherols (2,670–2,970 ppm). The bean oils had lower pour points (−18 to −11 °C) compared to −9 °C for soybean oil. Among the four bean oils, kidney bean oil had the highest acid value (15.4 mg KOH/g) and kinematic viscosities over a wide range of temperatures.  相似文献   

9.
The paper describes a study on effects of thermal treatments (microwave heating and freezing) on fish lipids‐amylose starch interactions. Particular attention was paid to lipid availability (extractability from the system) and contribution of fatty acids to various groups of lipids after interactions produced by mixing, microwave heating and storage. Analyses were made on model systems containing fish lipids at different oxidation levels and gelatinised with 10% aqueous solution of amylose starch. The lipid:starch ratio was 1:1. The systems were assayed before and after mixing, microwave heating (4 min, 90 W), freezing (30 d, –18 °C), and heating followed by freezing. Lipid extractability (selective extraction), peroxide value (PV), anisidine value (AsV), fluorescence, and fatty acid profiles (GC/MS) were determined. Mixing of fish lipids with amylose was shown to result in lipid‐amylose interaction. The thermal treatments applied (microwave heating or freezing at –19 °C for 30 d) were observed to exert different, significant effects on fish lipids‐amylose starch interactions. The effects depended also on the extent of lipid oxidation. Fatty acids of the lipids were bound selectively, PUFA, and particularly DHA, were subjected to stronger binding and higher amounts of those acids were bound.  相似文献   

10.
The microbial lipids isolated from oleaginous yeasts are a potential alternative to tree borne oils. There is a need to optimize and enhance the production of lipid by various stress approaches. In the present study, yeasts are subjected to physico-chemical stresses, and growth, as well as lipid concentration at different time intervals are monitored. It is found that the nanoparticles (NP) such as Ag-NP and Zn-NP have an inhibitory effect on yeast growth. Most yeast strains show an increase in growth and lipid accumulation when ionic liquid (1-ethyl-3-methylimidazolium acetate) ([EMIM][OAc]) and table salt (NaCl) stress are applied. Lipid is chemically characterized using gas chromatography furnished with flame ionization detector (GC-FID), GC/MS, and NMR techniques. It contains a higher percentage of saturated fatty acids (SFA: 74.3%), monounsaturated fatty acids (19.1%) with low amounts of polyunsaturated fatty acids (1.9%). The thermo-stability study reveals that the lipid have higher volatility (380–410 °C) as closely compared with coconut oil, and much lower with respect to the winged bean oil (430–470 °C). The melting point of the lipids (37 °C) is determined through differential scanning calorimetry (DSC). The DSC and physico-chemical properties are supported that the yeast lipids may use as a cocoa-butter substitute. Production of lipid under NaCl stress (200 × 10−3 m ) is more than 60.4% higher as compared to the control. However, the combined stress effect of NaCl (200 × 10−3 m ) and 15 × 10−3 m of [EMIM][OAc] results in more than 96.4% yield of lipid. The exchange of inorganic and organic ions in combined treatment forces the microbial cells to accumulate more amounts of lipid, which may form a lipid-emulsion layer to protect the cell from osmosis. It is interestingly observed that the stress cells shift the flux to accumulate a significantly improved percentage of SFA, which could be provided better protection cover due to its expanded structure, less reactive characteristics, and completely insoluble nature in ionic-aqueous solvent. Practical applications: Oleaginous yeast is multiplied in a very limited space, and easily scalable for sustainable production of lipid to meet its commercial demand. This novel approach for enhancing the yield of lipid with the application of synergistic stress in between NaCl and the green solvent (ionic liquid) is being reported for the first time. This lipid has potential alternative applications as cocoa-butter.  相似文献   

11.
Oil from coffee silverskin (CS) is a potential source of fatty acids with promising applications in several industries. Thus, CS crude oil extraction processes were investigated for further enzymatic hydrolysis for fatty acids production. Firstly, Soxhlet (with 150 mL hexane for 8 hours at 70 °C) and ultrasound-assisted (three times in sequential with 50 mL of hexane for 30 min at 30 °C) extractions were carried out to extract CS oil (3.8% and 3.1%, respectively). The fatty acid profiles obtained by both extraction methods presented a similar composition, shows palmitic (16:0: 32.6–34.4%) and linoleic acids (18:2: 31.5–36.1%) as the main. Then, CS oil extracted by Soxhlet was used as the feedstock for fatty acids production by enzymatic hydrolysis using four commercial lipases. Among the lipases studied, Candida rugosa lipase (CRL) displayed a higher hydrolytic activity (1143.70 U g−1), with a maximum hydrolysis degree of 51.94% (acid value of the CS oil increased from 13.4 to 37.5 mg KOH g−1) after 180 min of reaction. Molecular docking analysis showed that interactions between the CRL active site (Ser209 and His449) and palmitic acid, the fatty acid of highest concentration in CS oil (≈35%), lead to higher hydrolytic activity. The integrated process developed is an advance in fatty acid production and valorization of coffee industry waste, since there is still a promising approach yet to be explored that aims at the utilization of residual CS oil.  相似文献   

12.
Cephalocroton cordofanus, a perennial much-branched shrub, is dominant in the eastern and western states of Sudan. The seeds of C. cordofanus sesame, groundnut, and cotton were compared for their oil and protein content as well as for fatty acids, tocopherols, and sterols. Fatty acids and sterols were analyzed by GC while tocopherols were analyzed by HPLC. The oil of C. cordofanus showed low levels of saturated fatty acids in comparison with the other three oils. The other reported fatty acids of C. cordofanus were 8.60 % oleic, 17.2% linoleic, 64.2% vernolic, and 2.0% coronaric acids. Neutral lipids, glycolipids, and phospholipids of C. cordofanus oil accounted for 77.5, 14.4, and 8.1% of the total lipid fraction, respectively. The oil of C. cordofanus showed higher levels of tocopherols (113.53 mg/100 g) in comparison to sesame, groundnut, and cottonseed oils, with 64.74, 27.96, and 77.83 mg/100 g, respectively. The primary tocopherol of C. cordofanus was γ-tocopherol (106.21 mg/100 g), which amounted to 93.8% of the total tocopherols. β- and δ-tocopherol were present at levels below 5.0 mg/100 g. In comparison to sesame, groundnut, and cottonseed oils, C. cordofanus oil contains more (304.4 mg/100 g) total sterols than ground nut (294.0 mg/100 g), but less than sesame (774.9 mg/100 g) and cotton seed (492.4) oils. Due to its high level of epoxy fatty acids, C. cordofanus oil is used for industrial rather than edible applications.  相似文献   

13.
Montmorency sour cherry (Prunus cerasus L.) pit oil (CPO) was extracted and characterized by various methods including: GC, LC–MS, NMR, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X‐ray powder diffraction (XRD). The oil gave an acid value of 1.45 mg KOH/g, saponification value of 193 mg KOH/g and unsaponifiable matter content of 0.72 %. The oil contained oleic (O) and linoleic (l ) acids as the major components with small concentrations of α‐eleostearic acid (El, 9Z,11E,13E‐octadecatrienoic acid) and saturated fatty acid palmitic (P) acid. The CPO contained six major triacyglycerols (TAG), OOO (16.83 %), OLO (16.64 %), LLO (13.20 %), OLP (7.25 %), OOP (6.49 %) and LElL (6.16 %) plus a number of other minor TAG. The TAG containing at least one saturated fatty acid constitute 33 % of the total. The polymorphic behavior of CPO as studied by DSC and XRD confirmed the presence of α, β′ and β crystal forms. The oxidative induction time of CPO was 30.3 min at 130 °C and the thermal decomposition temperature was 352 °C.  相似文献   

14.
Chopra R  Sambaiah K 《Lipids》2009,44(1):37-46
Lipase-catalyzed interesterification was used to prepare different structured lipids (SL) from rice bran oil (RBO) by replacing some of the fatty acids with α-linolenic acid (ALA) from linseed oil (LSO) and n-3 long chain polyunsaturated fatty acids (PUFA) from cod liver oil (CLO). In one SL, the ALA content was 20% whereas in another the long chain n-3 PUFA content was 10%. Most of the n-3 PUFA were incorporated into the sn-1 and sn-3 positions of triacylglycerol. The influence of SL with RBO rich in ALA and EPA + DHA was studied on various lipid parameters in experimental animals. Rats fed RBO showed a decrease in total serum cholesterol by 10% when compared to groundnut oil (GNO). Similarly structured lipids with CLO and LSO significantly decreased total serum cholesterol by 19 and 22% respectively compared to rice bran oil. The serum TAGs level of rats fed SLs and blended oils were also significantly decreased by 14 and 17% respectively compared to RBO. Feeding of an n-3 PUFA rich diet resulted in the accumulation of long chain n-3 PUFA in various tissues and a reduction in the long chain n-6 PUFA. These studies indicate that the incorporation of ALA and EPA + DHA into RBO can offer health benefits.  相似文献   

15.
Mycelia of arachidonic acid-producing fungi belonging to the genusMortierella were found to convert an oil containing α-linolenic acid to an oil containing 5,8,11,14,17-cis-eicosapentaenoic acid (EPA). This conversion was observed when they were grown in a medium containing the oil, glucose and yeast extract at 28 C. On the screening of various oils, linseed oil, in which α-linolenic acid amounts to about 60% of the total fatty acids, was found to be the most suitable for EPA production. Under the optimal culture conditions, a selected strain,Mortierella alpina 20-17, converted 5.1% of the α-linolenic acid in the added oil into EPA, the EPA production reaching 1.35 g/l of culture broth (41.5 mg/g dry mycelia). This value corresponded to 7.1% (by weight) of the total fatty acids in the extracted lipids. The lipid was also found to be rich in arachidonic acid (12.3%). Other major fatty acids in the lipid were palmitic acid (4.4%), stearic acid (3.2%), oleic acid (13.5%), linoleic acid (13.7%), α-linolenic acid (38.5%) and γ-linolenic acid (0.9%).  相似文献   

16.
Detergent fractionation (Lanza process) offers a valuable separation process for edible oils that contain varying amounts of saturated and unsaturated fatty acids. The rice bran oil fatty acid distillate (RBOFAD), obtained as a major byproduct of rice bran oil deacidification refining process, was fractionated by detergent solution into a fatty acid mixture as follows: low-melting (19.00 °C) fraction of fatty acids as olein fraction (44.50 g/100 g) and high-melting (49.00 °C) fatty acids as stearin fraction (37.15 g/100 g). A high amount of palmitic acid (42.75 wt%) is present in stearin fraction, while oleic acid is higher (48.21 wt%) in the olein fraction. The stearin and olein fractions of RBOFAD with very high content of free fatty acids are converted into neutral glycerides by autocatalytic esterification reaction with a theoretical amount of glycerol at high temperatures (130–230 °C) and at a reduced pressure (30 mmHg). Acid value, peroxide value, saponification value, and unsaponifiable matters are important analytical parameters to identity for quality assurance. These neutral glyceride-rich stearin and olein fractions, along with unsaponifiable matters, can be used as nutritionally and functionally superior quality food ingredients in margarine and in baked goods as shortenings.  相似文献   

17.
Watermelon seed oil characteristics were evaluated to determine whether this oil could be exploited as an edible oil. Hexane extraction of watermelon seeds produced yields of 50% (w/w) oil. The refractive index, saponification and iodine value were 1.4712 (at 25 °C), 200 mg KOH/g and 156 g I/100 g, respectively. The acid and peroxide values were 2.4 mg KOH/g and 3.24 mequiv/kg, respectively. The induction time of the oil was also 5.14 h at 110 °C, which was measured for the first time. Total unsaturation contents of the oil was 81.6%, with linoleic acid (18:2) being the dominant fatty acid (68.3%). Considering that the watermelon seed oil was highly unsaturated, the relatively high induction time might indicate the presence of natural antioxidants. In addition, the influence of extraction parameters on extraction of oil from watermelon seed with hexane as a solvent was studied at several temperatures (40, 50, and 60 °C), times (1, 2, and 3 h) and solvent/kernel ratios (1:1, 2:1, and 3:1). The oil yield was primarily affected by the solvent/kernel ratio and then time and temperature, respectively. The protein content of the oil-free residue was 47%.  相似文献   

18.
The heartwood or root of Dalbergia odorifera T. Chen is an important traditional medicine in Asia. The aim of the present study was to evaluate the physicochemical properties, chemical composition and antioxidant activity of Dalbergia odorifera T. Chen seed oil. Oil, protein, carbohydrate, moisture, ash and total phenolic contents were found to be 12.96, 26.86, 42.58, 13.70, 3.90 and 5.55%, respectively. Free fatty acids, iodine number, peroxide value, saponification number and unsaponifiable matter were 1.66%, 106.53 g/100 g, 5.07 meq O2/Kg, 196.78 mg KOH/g and 1.70%, respectively. The oil showed high absorbance in the UV-B and UV-C ranges with potential for use as a broad spectrum UV protectant. The major fatty acids were linoleic acid (60.03%), oleic acid (17.48%) and palmitic acid (16.72%). The total tocopherol, total phenolics and β-carotene were 511.9, 351.1 and 62.2 mg/kg oil, respectively. In addition, the methanol extract of seed oil showed significant in vitro antioxidant activity in four assays including DPPH radical scavenging activity, reducing power, linoleic acid peroxidation inhibition and chelating activity. This study suggests that Dalbergia odorifera T. Chen seed oil has the potential to be used in new products in the functional food, cosmetic or pharmaceutical industries.  相似文献   

19.
A two-step technique combining pre-esterification catalyzed by cation exchange resin with transesterification catalyzed by base alkali was developed to produce biodiesel from rapeseed oil deodorizer distillate (RDOD). The free fatty acids (FFAs) in the feedstock were converted to methyl esters in the pre-esterification step using a column reactor packed with cation exchange resin. The acid value of oil was reduced from the initial 97.60 mg-KOH g? 1 oil to 1.12 mg-KOH g? 1 oil under the conditions of cation exchange resin D002 catalyst packed dosage 18 wt.% (based on oil weight), oil to methanol molar ratio 1:9, reaction temperature 60 °C, and reaction time 4 h. The biodiesel yield by transesterification was 97.4% in 1.5 h using 0.8 wt.% KOH as catalyst and a molar ratio of oil to methanol 1:4 at 60 °C. The properties of RDOD biodiesel production in a packed column reactor followed by KOH catalyzed transesterification were measured up the standards of EN14214 and ASTM6751-03.  相似文献   

20.
Saprolegnia sp. 28YTF-1, isolated from a freshwater sample, is a potent producer of 5,8,11,14,17-cis-eicosapentaenoic acid (EPA). The fungus used various kinds of carbon sources, such as starch, dextrin, sucrose, glucose, and olive oil for growth, and olive oil was the best carbon source for EPA production. The EPA content reached 17 mg/g dry mycelium (0.25 mg/L) when the fungus was grown in a medium that contained 2.5% olive oil and 0.5% yeast extract, at pH 6.0 and 28°C for 6 d with shaking. Accompanying production of arachidonic acid (AA; 3.2 mg/g dry mycelia, EPA/AA = 5.1) and other ω6 polyunsaturated fatty acids was low. Both EPA content and EPA/AA ratio increased in parallel by lowering growth temperature. Triglyceride was the major mycelial lipid (ca. 84%), but EPA comprised only 2.2% of the total fatty acids of this lipid. About 40% of the EPA produced was found in polar lipids, such as phosphatidylethanolamine (EPA content, 28.2%), phosphatidylcholine (13.6%), and phosphatidylserine (21.2%).  相似文献   

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