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241.
Porous composite scaffold with Ligusticum wallichii polysaccharide and squid skin collagen was synthesized and characterized. The composite scaffold showed good phosphate buffer solution (PBS) retention ability, slow biodegradation rate, high mechanical strength, and superb cell proliferation promoting ability. The PBS content value increased from 433.40% to 571.05%; the weight lost in seven days decreased from 95.41% to 34.35%; the tensile strength of sample increased from 0.19 to 0.81 MPa; the seven-day relative growth rate of cell in composite (polysaccharide:collagen = 5:5) is twice of that in pure collagen. While with the polysaccharide portion increased, the elongation at break decreased from 93.09% to 9.60%.  相似文献   
242.
Factors influencing the oxidative stability of refined squid visceral oil after various purification treatments were evaluated. Squid visceral oil was treated by refining, steam deodorizing, molecular distillation, Sep-Pak cartridge extraction, alumina adsorption, EDTA solution washing, and column chromatography, and the treated oils were compared for oxidative stability. Sep-Pak cartridge extraction and alumina adsorption were designed to eliminate phenolic compounds, α-tocopherol, phospholipids, and metal ions from the oil. The oxidative stability was measured using PV and increase in weight. The refined oil and the deodorized oil were the most stable, and the highly purified oil was the least stable. However, alumina-adsorbed oil that had been washed with EDTA was more resistant to oxidation than highly purified oil. When refined oil was passed through an activated carbon-Celite chromatography column, it could be separated into hexane, ether, and ethanol fractions. The ethanol eluate contained more α-tocopherol and phospholipids than the ether eluate. The addition of the ethanol eluate extracted from squid visceral oil to the highly purified oil resulted in excellent stability.  相似文献   
243.
鱿鱼热泵-热风联合干燥节能研究   总被引:4,自引:0,他引:4  
以热泵干燥阶段的温度、分阶段干燥的水分转换点、后期热风干燥阶段的温度为影响因素,以单位能耗除湿值(SMER)和总挥发性盐基氮值(T—VBN)两者的综合指标Y为最终评价指标进行响应面优化分析,得出了联合干燥最佳工艺参数:热泵干燥温度(X1=54.3℃)、水分转换点(X2=32.3%)和热风干燥温度(X3=43.5℃)。在最优工艺条件下比较HPD、HPD+AD、AD三种干燥方式下的样品品质和耗能,联合干燥得到的鱿鱼干品质高于热风干燥,而且降低了干燥能耗38.67%。  相似文献   
244.
Jumbo squid ( Dosidicus gigas ), an abundant species in the Gulf of California, can have a great potential for production of gelled-emulsified type products. Thus, formulation, processing and physicochemical characteristics of frankfurter-type product from jumbo squid mantle muscle (JSF) was achieved. JSF were vacuum-packed and stored at 2–4 °C. Samples were analysed for physicochemical (colour, texture, TBARS, peroxide value, folding test, pH, and water content and holding capacity) and microbial changes at regular intervals during storage for up to 27 days. The sensory quality of the product was also evaluated. Shear force, cohesiveness and colour (hue angle and total colour difference) were the most affected ( P  <   0.05) parameters at day 27, changes most probably because of microbial growth as total aerobic counts increased to >2.7 × 105 CFU g−1 (day 21). Product showed acceptability. Results suggest a stable gelled-emulsified type product can be developed from jumbo squid mantle muscle opening a range of possibilities for product development.  相似文献   
245.
A protein concentrate from giant squid (Dosidicus gigas) was produced under acidic conditions and its functional–technological capability evaluated in terms of its gel-forming ability, water holding capacity and colour attributes. Technological functionality of the concentrate was compared with that of squid muscle and a neutral concentrate. Protein–protein aggregates insoluble at high ionic strength (I = 0.5 M), were detected in the acidic concentrate as result of processing with no preclusion of its gel-forming ability during the sol-to-gel thermal transition. Even though washing under acidic condition promoted autolysis of the myosin heavy chain, the acidic concentrate displayed an outstanding ability to gel giving samples with a gel strength of 455 and 1160 g cm at 75% and 90% compression respectively, and an AA folding test grade indicative of high gel strength, elasticity, and cohesiveness. The process proved to be a good alternative for obtaining a functional protein concentrate from giant squid muscle.  相似文献   
246.
ABSTRACT: The present study was designed to evaluate the effect of a new iron tonic (squid ink melanin‐Fe [SM‐Fe]) on remission of iron deficiency anemia (IDA) using a rat model of IDA. The rat IDA model was established with low‐iron diet feeding and caudal vein blooding. Then different dosages of SM‐Fe were given to the rats once a day by intragastric administration, with FeSO4 and FeCl3 as positive control. The content of Hemoglobin (Hb), red blood cell (RBC), hematocrit (HCT), and mean corpuscular volume (MCV) were analyzed in addition to the contents of serum iron (SI) and intracellular free erythrocyte protoporphyrin (FEP). The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH‐Px) in serum was also measured. The results showed that anemia caused by iron deficiency was established as a consequence of the low‐iron diets. SM‐Fe showed an effective restoration action by returning Hb, RBC, HCT, MCV, SI, and FEP in IDA animals to normal values. An antioxidant effect was also observed that reduced MDA level, enhanced the activities of SOD and GSH–Px in serum, and protected erythrocytes from the injury of reactive oxygen species as a consequence of SM‐Fe intake. In comparison with FeSO4 and FeCl3, higher bioavailability of iron and fewer side effects were also observed. In conclusion, SM‐Fe remitted iron deficiency anemia symptoms significantly, suggesting that SM‐Fe might contribute to improving hemopoietic function in IDA rats and might be exploited as a safe, efficient new iron tonic.  相似文献   
247.
BACKGROUND: Trimethylamine oxide (TMAO) in squid is demethylated to dimethylamine (DMA) and formaldehyde (FA) during storage and processing. This study examined the effects of thermal processing and various chemical substances on FA and DMA formation in squid. RESULTS: The thermal conversion of TMAO was assessed by analysing four squid and four gadoid fish species, which revealed that FA, DMA and trimethylamine (TMA) were gradually produced in squid, whereas TMA increased and FA decreased in gadoid fish. A significant increase in both FA and DMA levels was observed in the supernatant of jumbo squid with increased heating temperature and extended heating time at pH 6–7. Ferrous chloride combined with cysteine and/or ascorbate had a significantly positive effect on FA formation in the heated supernatant of jumbo squid. No significant difference was observed in the levels of Cu and Fe in squid and gadoid fish. The capability of Fe2+ to promote the formation of FA and DMA was not completely attributable to its reducing power in squid. CONCLUSION: Non‐enzymatic decomposition of TMAO was a key pathway during the thermal processing of jumbo squid, and Fe2+ was a crucial activator in the formation of FA and DMA. Copyright © 2012 Society of Chemical Industry  相似文献   
248.
iSCSI协议性能分析   总被引:2,自引:0,他引:2  
iSCSI协议实现了通过IP网络存取SCSI设备.SCSI命令描述块被封装成iSCSI协议数据单元通过TCP/IP协议传送.iSCSI协议开销相对较大,iSCSI的性能受到网络最大传输单元和iSCSI协议参数的限制.  相似文献   
249.
目的以废弃鱿鱼顶骨为原料,在温和条件下提取并制备高强度、高透明度的β-甲壳素纳米纤维薄膜。方法常温下利用温和提取法,从鱿鱼顶骨中提取β-甲壳素纳米纤维(β-ChNF);通过真空抽滤,制备β-甲壳素纳米纤维薄膜(β-ChNF/m)。并与以蟹壳为原料“高温提取”制备所得的α-甲壳素纳米纤维薄膜(α-ChNF/m)进行对比;通过力学性能、结晶结构、微观构造、表面化学特性及透光性分析,探索“温和条件”提取法对薄膜性能的影响规律。结果利用温和提取法,能最大程度保留β-ChNF在鱿鱼顶骨中的天然纳米形态与性能;与从蟹壳中提取所得α-甲壳素相比,研究制备所得β-ChNF/m比α-ChNF/m力学强度提高了近1.5倍,断裂伸长率提高了3倍,且具备优异的透光性,透光率为90%,雾度为4%。结论以鱿鱼顶骨为原料制备所得β-ChNF/m具有优异的透光性、力学性能,有望作为柔性电子标签基材应用于智慧包装、包装智能检测等研究领域。  相似文献   
250.
We show that Image-EELS is suitable for detecting relatively low phosphorus concentrations in very small axoplasmic structures of squid axons. Imaging plates and a CCD camera were used as electron sensors. From image series spanning a certain energy-loss range EELS (electron energy-loss spectra) were derived by averaging read-outs from many axoplasmic particles (APs). The ratio of these spectra to spectra of the background was plotted, showing the contrast modulation as a function of the energy loss. This new approach is called EELC (electron energy-loss-dependent contrast spectroscopy). A distinct phosphorus signal was found in APs of presynaptic terminals of the squid giant synapse, in the peripheral giant axon and, as controls, in ribosomes. Biochemical experiments supported this result. In neurofilament-enriched pellets a phosphorus signal could be directly detected by serial EELS and in electron spectroscopic micrographs. After dephosphorylation of either the pellets or the extruded axoplasm with alkaline phosphatase, phosphorus signals in electron spectroscopic micrographs were absent or much reduced in size and intensity. With Image-EELS inherent limitations of traditional element detection modes in energy filtering transmission electron microscopy can be overcome. Compared with serial EELS, the selective analysis of small areas with irregular shape is possible with greatly improved signal-to-noise ratio. The identification of the element-peak in Image-EEL spectra directly proves the presence of the element within the region of interest. For small peaks, the visualization is facilitated by the contrast presentation (EELC). However, the background subtraction modes used for elemental mapping in electron spectroscopic imaging are subject to uncertainties when elemental ionization edges like the PL2,3 edge are examined. Imaging plates are very sensitive electron sensors with a wide dynamic range. Unlike photographic emulsions, they allow acquisition of image series covering a large energy-loss range without normalization of exposure times, and direct extraction of EEL spectra. Thus, the combination of Image-EELS and imaging plates is proposed as an efficient new tool for analytical electron microscopy.  相似文献   
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