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1.
Waste cooking oil (WCO) is a problematic waste product that contains free fatty acids (FFAs), preventing it from being valorized easily as biodiesel and poses an environmental hazard if incorrectly disposed. The use of WCO as a carbon source for Rhodosporidium toruloides (R. toruloides) using a two-phase culture system is developed. The normal growth of R. toruloides when cultured in WCO (OD600 52) reveals its ability to use a hydrophobic substrate as the carbon source compared to glucose (OD600 51.9). Interestingly, the extracellular lipase activity when R. toruloides is grown on WCO is 14.4 U mL−1 compared to when grown on glucose (2.4 U mL−1). Additionally, FFA levels in WCO are reduced from 2% to 0.2% at end of fermentation, suggesting that R. toruloides can consume FFA. Furthermore, higher yield of beneficial products: β-carotene (4.57 µg mL−1), torularhodin (4.2 µg mL−1), fatty acids (1 mg mL−1), and phenylalanine ammonia-lyase (PAL) enzyme (0.12 µmol mg−1) are produced when WCO is the carbon source, compared to glucose (4.1 µg mL−1 β-carotene, 3.0 µg mL−1 torularhodin, 1 mg mL−1 of fatty acids, and 0.096 µmol mg−1 PAL enzyme). This is a first study that shows R. toruloides can grow on hydrophobic carbon source.  相似文献   

2.
It has been well confirmed ox-LDL plays key roles in the development of atherosclerosis via binding to LOX-1 and inducing apoptosis in vascular endothelial cells. Recent studies have shown ox-LDL can suppress microRNA has-let-7g, which in turn inhibits the ox-LDL induced apoptosis. However, details need to be uncovered. To determine the anti-atherosclerosis effect of microRNA has-let-7g, and to evaluate the possibility of CASP3 as an anti-atherosclerotic drug target by has-let-7g, the present study determined the role of hsa-let-7g miRNA in ox-LDL induced apoptosis in the vascular endothelial cells. We found that miRNA has-let-7g was suppressed during the ox-LDL-induced apoptosis in EAhy926 endothelial cells. In addition, overexpression of has-let-7g negatively regulated apoptosis in the endothelial cells by targeting caspase-3 expression. Therefore, miRNA let-7g may play important role in endothelial apoptosis and atherosclerosis.  相似文献   

3.
The absolute concentration of phospholipids (PL) (μmol g?1, wet tissue) in five marine tissues was determined using quantitative phosphorous nuclear magnetic resonance spectroscopy (31P NMR). Hoki (Macruronus novaezelandiae) roe was identified as a “high‐PL” seafood, containing 15.97 ± 4.72 μmol g?1 (wet tissue) of these compounds. This was 2–4× higher than the concentration of PL in monkfish (Lophius spp.) fillets (4.26 ± 1.52), arrow squid (Nototodarus sloanii) mantle (8.95 ± 0.89), Greenshell? mussel (Perna canaliculus) (7.04 ± 0.87), or hoki liver (6.03 ± 0.76). The amount of PL extracted from these tissues was dependent on the extraction method used, with the Folch (1957) method consistently extracting more oil (and more PL) from all five tissues than the Bligh and Dyer (1959) and Jensen (2003) methods. The individual PL profiles of each tissue are also reported.  相似文献   

4.
The objectives of the study are to investigate the protective effects of eight phospholipids (PL) with different fatty acids or polar head groups on obesity-induced renal damage. Four kinds of phosphatidylcholine (PC) are exacted from egg york (Egg-PC), soybean (Soy-PC), squid roe (DHA-PC) and sea cucumber (EPA-PC). Furthermore, four kinds of phosphatidylethanolamine (PE) are enzymatically synthesized from PC, respectively. Male C57BL/6J mice are fed with standard diet, high-fat diet (Model) or high-fat diet containing 2% phospholipids for 8 weeks. Mice in the model group demonstrate severe renal injury. Different phospholipids improve renal dysfunction in high-fat diet mice to varying degrees, and EPA-PE shows the best effects on reducing serum Cr, chronic inflammation and renal lipid accumulation. A further mechanistic study reveals that the lipid-lower effect of phospholipids might be attributed to increased fatty acid β-oxidation and decreased fatty acid synthesis. Finally, it seemed that the influence of phospholipids on the PGC1α activation appear to be dependent on FA saturation, as DHA/EPA-PL increases the expression of PGC1α greater than Soy-PL, as well as Egg-PL. Practical Applications:Based on these findings, phospholipids are promising supplement for alleviation of obesity-induced renal dysfunction, and their different protective effects mainly due to the fatty acids composition.  相似文献   

5.
Tocher DR  Sargent JR 《Lipids》1984,19(7):492-499
Lipid class analyses and fatty acid analyses of neutral and polar lipids were carried out on ripe roes of herring, cod, haddock, whiting, saithe, sand eel and capelin. Total lipid was 10–26% of roe dry weight. The species with the highest total lipid, sand eel and capelin, also had the highest percentage of neutral lipid in total lipid, 77% and 49% respectively. In the other species, phospholipids accounted for 62–77% of roe total lipid. Both the neutral lipids, and especially the phospholipids, of all species were very unsaturated because of high concentrations of (n−3) polyunsaturated fatty acids (PUFA), frequently amounting to 50% of the total egg lipid. Phosphatidylcholine (PC) and phosphatidylethanolamine (PE) had similar fatty acid compositions in all species, with an average ratio (n−3)/(n−6) of ca. 20∶1. Phosphatidylinositol (PI) consistently had high concentrations of 18∶0 and 20∶4 (n−6) with an average ratio of (n−3)/(n−6) of 1.8∶1. Requirements for high levels of (n−3) PUFA in the embryonic and early larval development stages of marine fish are suggested as is a special role for the 20∶4(n−6) in PI.  相似文献   

6.
Consumers are becoming concerned about the impact of synthetic chemicals on human health and environments, and demanding natural compounds to reduce risk of antibiotic resistance of microorganisms. However, natural compounds are often less effective than synthetic antimicrobials. This challenge may be addressed with the development of bio-based antimicrobial agents. In this study, bio-based n-phenolic branched-chain fatty acids (n-phenolic-branched chain fatty acid [BCFA]) were synthesized from vegetable oil (soybean and safflower) fatty acids and four natural phenolics (phenol, thymol, carvacrol, and creosote), and tested against Listeria innocua. Results revealed that the newly synthesized products in crude form had minimum inhibitory concentrations (MIC) against L. innocua ranging from 3.6 to 116.4 μg mL−1, with phenol-BCFA products having the lowest MIC (3.6 μg mL−1) and minimum bactericidal concentration (MBC) (7.3 μg mL−1). The precursors (unsaturated free fatty acids and phenolics) and noncovalently bound mixture of free fatty acids and phenolics had MIC above 232.7 μg mL−1. After purification by molecular fractionation, n-phenolic-BCFA in the free fatty acid/monomer form were shown to be responsible for the anti-Listeria activity with MIC of 3.6–7.3 μg mL−1 and MBC of 7.3–29.1 μg mL−1. These promising results pave the road for further study of this new class of bio-based compounds, which may lead to their widespread use.  相似文献   

7.
Hybrid materials with enhanced antibacterial activity were prepared by incorporation of carbon nanotubes within gelatin-fluoroquinolones bioconjugates. Gelatin bioconjugates were characterized by UV-Vis, FT-IR, and calorimetric analyses, nanohybrids by morphological analyses. Biocompatibility was evaluated on human mesenchymal stem cells, and antibacterial performance against Klebsiella pneumoniae and Escherichia coli. Minimun inhibitory concentrations from 0.025 to 0.05 µg mL?1 and from 0.025 to 0.10 µg mL?1, and MBC from 0.025 to 0.10 µg mL?1 and from 0.05 to 0.20 µg mL?1 were detected for Escherichia coli and Klebsiella pneumoniae, respectively, showing that nanotubes increase antimicrobial activity comparing to both free and gelatin-conjugated drugs.  相似文献   

8.
Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were distributed mainly in the sn-1,3 positions of seal oil triglyceride and in the sn-2 position of squid oil triglyceride. Seal oil-rich or squid oil-rich fats having constant saturated/monounsaturated/polyunsaturated fatty acid (PUFA) and n−6/n−3 PUFA ratios were fed to exogenously hypercholesterolemic rats for 160 d. The control fat contained linoleic acid as the sole PUFA. Before starting the experimental diets, rats were orally treated with high doses of vitamin D for 4 d to accelerate atherogenesis. The percentage of arachidonic acid in phosphatidylcholine and phosphatidylethanolamine of liver, platelets, and aorta was lower in the marine oil groups than in the control group, seal oil being more effective than squid oil. Maximal platelet aggregation induced by collagen was significantly lower both marine oil groups. Platelet thromboxane (TX) A2 production induced by collagen or thrombin was markedly reduced by feeding seal or squid oils, the reduction being more pronounced in the seal oil than in the squid oil group. Aortic prostacyclin (PGI2) production was the same among the three groups. The ratio of the productions of aortic PGI2 and platelet TXA2 was significantly higher in the seal oil than in the control group. Although there was no difference in intimal thickness among the three groups, the aortic cholesterol content was significantly lower in the marine oil groups than in the control group. These results showed that the main effects in rats of the different intramolecular distributions of EPA and DHA in dietary fats were on arachidonic acid content in tissue phospholipids and on platelet TXA2 production.  相似文献   

9.
Corn gluten meal (CGM) is a protein-rich coproduct generated during corn wet milling. In this study, CGM was hydrolyzed using Neutrase protease for 1 and 3 hours, respectively, to obtain antioxidative corn gluten meal protein hydrolysates (CGMPH), which could be a potential antioxidant in various products to retard lipid oxidation. Our objective was to evaluate the emulsion properties and oxidation stability of oil-in-water emulsions containing different types (1-hour and 3-hour hydrolysates) and amounts of CGMPH. The results showed that the emulsions with CGMPH had significantly improved oxidative stability than the control based on both peroxide value and thiobarbituric acid reactive substance (TBARS) analysis. The emulsion with higher concentration of CGMPH (e.g., 5 mg mL−1) showed more effective inhibition on lipid oxidation. The emulsion turbidity of 1-hour CGMPH at 2.5 mg mL−1 had a lower value than that of other emulsions, and overall, the turbidity for 3-hour CGMPH had a slightly higher value than that with 1-hour CGMPH. Addition of CGMPM did not affect emulsion morphology and droplet sizes. Zeta potential analysis showed that emulsions with 1-hour hydrolysate had more negative charges with better emulsion stability than that with 3-hour hydrolysate at the same pH. In conclusion, the CGMPH were able to inhibit lipid oxidation in reducing the formation of hydroperoxides and TBARS, and could be a potential functional antioxidant for food emulsion applications.  相似文献   

10.
The full characterization of chitin obtained from squid, shrimp, prawn, lobsters, and king crab is reported. Elemental analysis, including metals such as Ca, Mg, Zn, Cd, Hg, Cr, Mn, Cu, and Pb, was performed, which is quite relevant because the skeleton composition is slightly different for each species. The morphology was studied by means of TEM and their compositions were determined by energy‐dispersive X‐ray analysis. 13C cross polarization/magic angle spinning NMR was applied to determine the chemical shift of all the carbons and the difference between them. Chitin was isolated by using chemical methods, alternating hydrochloric acid and sodium hydroxide. The α‐chitin from shrimp, prawn, lobsters, and king crabs showed two signals at 73.7 and 75.6 ppm. Meanwhile, the β‐chitin from squid exhibited one signal at 75.2 ppm. FTIR studies were used to analyze α‐chitin from shrimp and β‐chitin from squid. The α‐chitin exhibited amide I vibration modes at 1660 and 1627 cm?1, whereas the β‐chitin showed one band at 1656 cm?1. X‐ray diffraction showed that α‐chitin is orthorhombic (a = 4.74 Å, b = 18.86 Å, and c = 10.32 Å) and β‐chitin had a monoclinic dihydrated form (a = 4.80 Å, b = 10.40 Å, c = 11.10 Å, and β = 97°). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1876–1885, 2004  相似文献   

11.
Shrimp oil nanoliposomes (SONL) were fortified into skim milk at various levels (2–10%, v/v), followed by pasteurization at 63 °C for 30 min. Skim milk showed lowered whiteness but increased redness and yellowness as SONL levels added increased (P < 0.05). Viscosity of fortified samples was also augmented with increasing levels of SONL (P < 0.05). Sensory analysis indicated that fortified milk skim samples had no perceivable fishy odor and were organoleptically acceptable. When skim milk fortified with 10% SONL was stored up to 15 days at 4 °C, the microbial load was less than 2.54 log CFU mL−1. The pH and acidity values were also within the acceptable limits. As measured by peroxide value (PV) and thiobarbituric acid reactive substances (TBARS), shrimp oil in SONL did not undergo oxidation during the extended storage. The fatty acid profile of shrimp oil revealed no loss of polyunsaturated fatty acids taken place during the storage of fortified milk. Therefore, nanoliposomes could be an effective carrier for shrimp oil to be fortified in skim milk.  相似文献   

12.
The effects of feeds containing several food by-products on the fatty acid compositions of Hermetia illucens larvae were studied. Coconut, tomato, apple, and viscera by-products, as well as combinations of control feed containing carbohydrate-rich additives were assayed. Final live weight (mg) and daily growth coefficient (%/day) ranged from 41 and 0.548 (tomato) to 93 and 1.292 (coconut), respectively. Oils containing lauric acid were obtained from larvae-fed vegetable by-products, especially those fed feed containing apple, coconut, and tomato (65.3, 54.4 and 52.3% of total fatty acids, respectively). Feed containing apple and a 1:1 (w/w) mix of control feed and apple by-products yielded the highest proportion of fatty acids in the larvae (23.5 and 15.6 g fatty acids/100 g fresh larvae, respectively). The properties of biodiesel that could be produced from larvae fatty acids were calculated and the following values were obtained: cetane number (58.5–60.2), higher heating value (38.3–39.0 MJ·kg−1), density (0.869–0.873 g·cm−3), and induction period, an index of oxidation stability (8.4–150 hours). Such values were within the ranges specified by the ASTM D6751 and Europe EN 14214:2008 standards, while values for cold filter plugging point (−9.6 to 2.8 °C) were adequate for biodiesels intended for use in temperate climates. However, values for kinematic viscosity (2.93–3.58 mm2·s−1) were slightly below the requirements of EN 14214:2008 (3.5–5.0). Overall, larvae fed food by-products produced lauric acid-rich oils, and the calculated properties of the oils were largely suitable for biodiesel production.  相似文献   

13.
Unlike their terrestrial counterparts, marine myxobacteria are hardly investigated for their secondary metabolites. This study describes three new compounds ( 1 – 3 ), named salimyxins and enhygrolides, obtained from the obligate marine myxobacterium Enhygromyxa salina. These are the first natural products obtained from Enhygromyxa species. Their structures were elucidated by spectroscopic analysis, including NMR and CD spectroscopy. Enhygrolides are closely related to the nostoclides, which were initially isolated from a cyanobacterium of the genus Nostoc. The salimyxins, representing structurally most unusual degraded sterols, are close to identical to demethylincisterol from the sponge Homaxinella sp. Salimyxin B and enhygrolide A inhibit the growth of the Gram‐positive bacterium Arthrobacter cristallopoietes (MIC salimyxin B, 8 μg mL?1; enhygrolide A, 4 μg mL?1).  相似文献   

14.
Sodium alginate was hydrophobically modified with dodecenyl succinic anhydride in a neutral aqueous solution (pH = 6.8) at room temperature, forming an environmentally friendly amphiphile dodecenyl-modified alginate (DMA). Surface activity of DMA was assessed using surface tension and zeta-potential measurements. Hydrophobic compound-loading capacity as well as oil-in-water emulsion stability of DMA solutions were investigated to study the potential applications of DMA. The critical micelle concentration (CMC) of DMA aqueous solution was found to be 0.70 mg mL−1 with the surface tension being around 33.0 mN m−1. DMA solutions were able to solubilize hydrophobic compounds like Sudan IV and Clofazimine in aqueous medium. 10% peanut oil-in-water emulsions stabilized by 10 mg mL−1 DMA presented good stability during 7 days of storage and the interfacial tension between water and oil was lowered from 23.0 to 9.0 mN m−1. Results showed that DMA was an efficient surfactant and could work as a drug-delivery vehicle or a natural food emulsion stabilizer in the future.  相似文献   

15.
Lignocellulosic sisal fiber (LSF) and sisal pulp (SP) were electrospun at room temperature from solutions in trifluoroacetic acid (TFA) prepared at concentrations of 2 × 10−2 g mL−1 and 3 × 10−2 g mL−1, respectively. Scanning electron microscopy images of the electrospun LSF showed fibers with diameters ranging from 120 to 510 nm. The presence of defects decreased along with increasing the flow rate of the SP solution, which generated nanofibers and ultrathin fibers with diameters in the range of 40–60 (at 5.5 µL min−1) up to 90–200 nm (at 65.5 µL min−1). Despite the known ability of TFA to esterify the hydroxyl groups present in the starting materials, the Fourier transform infrared spectra indicated the absence of trifluoroacetyl groups in the electrospun samples. The thermal stability of the final materials proved suitable for many applications even though some differences were observed relative to the starting materials. This study demonstrated a feasible novel approach for producing nano/ultrathin fibers from lignocellulosic biomass or its main component, which allows for a wide range of applications for these materials. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41826.  相似文献   

16.
Striped mullet (Mugil cephalus) roe is used for the production of high nutritional and added-value delicacies. Its lipid fraction is rich in polyunsaturated fatty acids (PUFA) and bioactive compounds. This study examines scalable oil extraction methods for mullet roe oil extraction. Namely, solvent extraction (SE) using ethanol in two different temperatures, supercritical fluid extraction (SFE) using CO2-ethanol mixture (SFE-E) in two different temperatures, expeller oil press (EP) extraction, expeller oil press combined with ethanol extraction (EP-SE) and wet reduction (WR) are examined. The methods are evaluated with regard to the oil yield and recovery, the oil oxidation and the composition in fatty acids, and polar compounds and unsaponifiable matter. EP-SE and SE provide the highest oil recovery for tested extraction temperatures (76% and 65% respectively), followed by SFE-E (46%) and EP (36%). Extracted oils present high PUFA content (28.5–33.9%). The type of extraction process and the process variables affect oil oxidation as well as the concentration of polar compounds and unsaponifiable matter. In terms of oxidation levels, 85% of the extracted oil samples were within the limits set by the Codex Alimentarius Commission. The potential of the examined methods for industrial mullet roe oil production is discussed. Practical applications : Oil rich in polyunsaturated fatty acids was extracted from stripped mullet roe. The work proposes several scalable extraction methods using mild conditions which could be applied to obtain edible and high nutritional value mullet roe oil with high recovery reaching up to 76%. The same methods could be employed also for mullet roe by-products. The obtained results improve the knowledge regarding the potential of roe valorization for oil extraction as well as the effect of the extraction method on the oil yield, main composition features and the quality characteristics of oil extracted by mullet roe. This research could offer new opportunities for the food industry for fish roe valorization for high nutritional quality oil production.  相似文献   

17.
《Ceramics International》2023,49(19):31744-31751
Transferrin (TRF) is a type of glycoprotein present in blood plasma that plays a vital role in facilitating the absorption, storage, and movement of iron(III) ions within the circulatory system of multiple vertebrates. Herein, we report one-pot solvothermal synthesis of Copper Metal-Organic Framework nanosheets modified nickel foam (Cu-MOF/NF) for electrochemical detection of transferrin (TRF) in simulated human blood serum. The crystal structure of the Cu-MOF nanosheets was determined through X-ray diffraction (XRD), while Raman spectroscopy and Fourier-transform infrared spectroscopy (FTIR) analysis were employed to investigate the vibrational modes and the presence of surface OH groups, respectively. The nanosheet morphology of the Cu-MOF was observed and characterized using scanning electron microscopy (SEM) micrographs.The as-fabricated Cu-MOF/NF exhibits a sensitivity of 1.36 mA/x (x = mg.mL−1cm−2) for a linear range of concentrations from 1 mg mL−1 – 100 mg mL−1 with a low limit of detection (LOD) of 0.81 mg mL−1. The sensor exhibited good selectivity for TRF, even in the presence of interfering ions such as bovine serum albumin, ascorbic acid, uric acid, and urea, with concentrations 100-fold higher than TRF. The porous nickel foam with high conductivity, offers numerous active sites and pathways for ion transport, as well as pathways for electron transport during electrochemical catalytic reactions. This performance of the sensor is attributed to Cu 2+/Cu+ redox couple at the octahedral sites of the Cu-MOF facilitating the electro-oxidation of TRF and charge-carrier delocalization during the catalytic reaction. The as-fabricated sensor is successful in the determination of trace level TRF concentration the human blood serum with excellent recovery percentages of 108.33% This proves Cu-MOF/NF as a promising platform for various electrochemical analytical applications.  相似文献   

18.
Chitin from squid pen (Loligo sp.) and kiddi shrimp shell (Parapenaeopsis stylifera) were treated at room temperature (30 ± 2°C) with four different concentrations of sodium hydroxide: 20, 30, 40, and 50% w/w. With 50% sodium hydroxide solution, within 108 h, the chitin from squid pen was deacetylated to give chitosan. But it required 126 h at 40% and 144 h at 30% concentration of sodium hydroxide. In the case of chitin from Parapenaeopsis stylifera, complete deacetylation took place after 120 h and 168 h at 50 and 40% concentrations of sodium hydroxide, respectively. But shrimp shell on treatment with 20 and 30% sodium hydroxide solutions and squid pen kept at 20% sodium hydroxide were not sufficiently deacetylated even after 480 h. Properties like degree of deacetylation, viscosity and molecular weight of the prepared chitosan samples were studied. Minimum alkali concentration required for the formation of chitosan at room temperature was found to be 30% for squid chitin and 40% for shrimp chitin. With the increase in the time of deacetylation, decreases in molecular weight and viscosity were observed in chitosan from both sources. Maximum viscosity was recorded by chitosan prepared from squid pen using 30% sodium hydroxide solution at room temperature.  相似文献   

19.
Atherosclerosis is considered an inflammatory disease. However, clinically used anti-atherosclerotic drugs, such as simvastatin, have many side effects. Recently, several unique marine compounds have been isolated that possess a variety of bioactivities. In a previous study, we found a synthetic precursor of the marine compound (austrasulfone), which is dihydroaustrasulfone alcohol (WA-25), has anti-atherosclerotic effects in vivo. However, the detailed mechanisms remain unclear. Therefore, to clarify the mechanisms through which WA-25 exerts anti-atherosclerotic activity, we used RAW 264.7 macrophages as an in vitro model to evaluate the effects of WA-25. In lipopolysaccharide (LPS)-stimulated RAW 264.7 cells, WA-25 significantly inhibited expression of the pro-inflammatory proteins, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). In contrast, simvastatin increased the COX-2 expression compared to WA-25. In addition, WA-25 impedes foam cell formation and up-regulated the lysosomal and cyclic adenosine monophosphate (cAMP) signaling pathway. We also observed that transforming growth factor β1 (TGF-β1) was up-regulated by WA-25 and simvastatin in LPS-induced RAW 264.7 cells, and the promising anti-atherosclerosis effects of WA-25 were disrupted by blockade of TGF-β1 signaling. Besides, WA-25 might act through increasing lipolysis than through alteration of lipid export. Taken together, these data demonstrate that WA-25 may have potential as an anti-atherosclerotic drug with anti-inflammatory effects.  相似文献   

20.
The rise of antibiotic resistance, especially in Staphylococcus aureus, and the increasing death rate due to multiresistant bacteria have been well documented. The need for new chemical entities and/or the identification of novel targets for antibacterial drug development is high. Lipoteichoic acid (LTA), a membrane-attached anionic polymer, is important for the growth and virulence of many Gram-positive bacteria, and interest has been high in the discovery of LTA biosynthesis inhibitors. Thus far, only a handful of LTA biosynthesis inhibitors have been described with moderate (MIC=5.34 μg mL−1) to low (MIC=1024 μg mL−1) activities against S. aureus. Herein we describe the identification of novel compounds that potently inhibit LTA biosynthesis in S. aureus, displaying impressive antibacterial activities (MIC as low as 0.25 μg mL−1) against methicillin-resistant S. aureus (MRSA). Under similar in vitro assay conditions, these compounds are 4-fold more potent than vancomycin and 8-fold more potent than linezolid against MRSA.  相似文献   

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