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1.
《中国海洋大学学报(自然科学版)》2016,(4)
虾青素具有极强的抗氧化、抗癌变和增强免疫力等功能,但由于虾青素水溶解性(分散性)的限制致使其生物利用度和应用范围有很大的局限性。本文以丁二酸酐和合成虾青素为原料(摩尔比为10∶1),以三乙胺为催化剂(与合成虾青素的摩尔比为3∶1),合成虾青素琥珀酸二酯;经硅胶柱层析,用氯仿-甲醇(90∶10,v/v)混合液进行洗脱纯化;用高效液相色谱对合成的虾青素琥珀酸二酯进行分析,测得其纯度达95%;经紫外光谱扫描,测得其最大吸收波长为487nm,与虾青素的最大吸收波长接近。薄层色谱结果显示,虾青素琥珀酸二酯的极性增大,LC-(APCI)MS/MS分析得到其分子量为796.5,从其裂解碎片中可得到虾青素的碎片离子m/z561.5和m/z579.5。通过1 H NMR和DEPTQ谱进行验证,合成产物为虾青素琥珀酸二酯。 相似文献
2.
柱前衍生-RP-HPLC方法测定水产品中生物胺 总被引：1，自引：0，他引：1
建立同时测定水产品中多种生物胺的丹磺酰氯柱前衍生反相高效液相色谱方法。用5%TCA提取样品中生物胺,正己烷脱脂,正丁醇/氯仿(1/1,v/v)萃取,以1,7二胺庚烷为内标,丹磺酰氯为衍生剂衍生后,采用CAPCELL PAK C18MG(4.6 mm I.D.×150 mm,5μm)色谱柱,以甲醇/水为流动相,进行梯度洗脱,流速1.5 mL/min。荧光检测器的激发波长(Ex)350 nm,发射波长(Em)520 nm。结果显示:色胺、苯乙胺、腐胺、尸胺、组胺、酪胺、精胺和亚精胺等8种生物胺在30 min内完全分离。在给定的浓度范围内,待测生物胺峰面积与内标峰面积之比同其相应浓度呈良好的线性相关(r>0.99)。仪器重复性良好(RSD<1.34%),方法重复性也在可接收范围内(RSD<10%)。除色胺(57.7%)外,其它7种生物胺的样品平均回收率均在94.2%~110.3%之间。结果表明生物胺的HPLC检测方法,分离度好,灵敏度高,可快捷、准确地对水产品中生物胺进行定性和定量检测。 相似文献
3.
海带中细胞激动素的纯化分离方法 总被引：1，自引：0，他引：1
海带样品于 2 0 0 1年采自青岛太平角海湾 ,用三种不同方法处理样品 ,通过对实验方法及条件的筛选 ,确立了提取、纯化和分离海带中细胞激动素的方法步骤和流程。结果表明 ,最佳方法的基本步骤为 :( 1 )用甲醇∶水∶醋酸 ( 70∶ 30∶ 3,V/V/V)从海带组织中提取出细胞激动素 ,再用PVPP柱去除提取液中的酚类和其他杂质 ;( 2 )将提取液通过连在一起的PVPP柱、DEAE柱和C1 8柱 ,以纯化样品并同时从自由基、核苷、核苷酸和葡糖苷型细胞激动素混合物中分离出核苷酸型细胞激动素 ;( 3)用接有氨基柱的正相液相色谱进一步将葡糖苷型细胞激动素分离出来 ;( 4 )用C1 8液相色谱柱分离其他各种细胞激动素 相似文献
4.
《中国海洋大学学报(自然科学版)》2016,(9)
利用高效液相色谱-四极杆-飞行时间串联质谱法(LC-Q-TOF)分析比较冰岛刺参(Cucumaria frondosa)和南非花刺参(Stichopus variegatus)脑苷脂的分子种组成。以氯仿-甲醇(2∶1,V/V)溶液提取,经皂化和SPE净化,在正离子模式下,通过自动二级(MS/MS)方式同时获取脑苷脂分子的一级和二级质谱图。筛取含180Da中性丢失碎片的分子,再结合二级质谱中的长链碱和脂肪酸碎片,确定每种脑苷脂分子的结构。研究表明:一次性从冰岛刺参中分析出56种脑苷脂分子,从南非花刺参中分析出109种脑苷脂分子;南非花刺参含长链碱种类较多,为15种,冰岛刺参含长链碱11种。冰岛刺参脑苷脂中鞘氨醇型长链碱占91.84%,南非花刺参脑苷脂中鞘氨醇型长链碱占85.97%;脂肪酸的组成均为17~25碳的饱和或单不饱和脂肪酸,且以24碳脂肪酸为主。冰岛刺参脑苷脂中2-羟基脂肪酸占总脂肪酸的33.50%,饱和脂肪酸∶单不饱和脂肪酸≈2∶3;南非花刺参脑苷脂中2-羟基脂肪酸占总脂肪酸的76.73%,饱和脂肪酸∶单不饱和脂肪酸≈2∶1。研究结果显示,在抑制肿瘤细胞增长、预防癌症方面南非花刺参脑苷脂较冰岛刺参脑苷脂可能具有更好的生物活性。本研究为不同海参脑苷脂的活性研究和营养评价提供了参考与借鉴。 相似文献
5.
高效液相色谱法测定食品中嘌呤含量 总被引：3，自引：0，他引：3
为测定食品中嘌呤含量,建立了食品中多组分嘌呤含量测定的反相离子对高效液相色谱(RP-IP-HPLC)分析方法,对几种主要食品中的腺嘌呤、鸟嘌呤、黄嘌呤、次黄嘌呤含量进行测定。结果表明,采用Agilent XDB-C18色谱柱,水-甲醇-冰乙酸-10%四丁基氢氧化铵(V/V/V/V,879/100/15/6)为流动相,检测波长为254nm,流速为1mL/min时4种嘌呤可完全分离。测得4种嘌呤物质的回收率在91.8%~108.7%之间,方法的相对标准偏差(RSD)为2.7%~6.5%。不同种类食品中嘌呤总含量由高到低依次为:动物肝脏、动物肌肉、果蔬、菌类和蛋类。 相似文献
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7.
超声波辅助提取RP-HPLC法测定浒苔中的叶绿素a、b 总被引：3，自引：0，他引：3
建立了一种反相高效液相色谱法(RP-HPLC)测定浒苔(Enteromorpha prolifera)中叶绿素a和b含量。采用的色谱条件:Diamonsil-C18(4.6mm×150mm)柱,流动相为甲醇(含0.2%的乙酸)和丙酮,梯度洗脱,流速为0.8mL/min,进样量10μL,检测波长430nm。在此条件下,叶绿素a和叶绿素b与浒苔中的其他化合物分离良好,叶绿素a、b质量浓度为0.50～500mg/L具有良好的线性关系(R2=0.9999),能对浒苔提取液中的叶绿素a、b进行准确定量。 相似文献
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9.
建立了聚合度2～10的壳寡糖的薄层层析分析(TLC)方法,在异丙醇∶水∶氨水=60∶30∶4的展开体系中,各壳寡糖可以得到很好的分离,各单体间比移值(Rf)差异明显,无拖尾现象。通过对比TLC法与高效液相色谱(HPLC)法分析壳寡糖单体的效果,得出TLC法具有快速、有效、方便的优点,可以作为定性分析壳寡糖单体纯度的方法。采用本实验室制备的壳聚糖酶对3种不同脱乙酰度的壳聚糖和DP2～6的壳寡糖进行水解,采用TLC法对水解产物进行分析。实验结果表明,随着壳聚糖脱乙酰度的降低,其酶水解产物的糖链延长。该壳聚糖酶不能水解DP2～4的壳寡糖,对DP5～6的壳寡糖水解速率缓慢。通过对该壳聚糖酶作用特点分析,表明该酶可作用于GlcN-GlcN糖苷键,而不能水解Glc-NAc-GlcNAc糖苷键。 相似文献
10.
螺旋藻单半乳糖二酰甘油酯脂肪酸分子组成分析 总被引：3，自引：0，他引：3
采用硅胶柱层析法，从螺旋藻总脂中分离提取出单半乳糖二酰甘油酯(MGDG)，通过高效液相色谱(HPLC)分离纯化得到7个主要组分。经酶解(Lipase XI,Rhizopus arrhizus)、酯化,通过气相色谱(GC)分析MGDG及7其个主要组分中脂肪酸含量和分子组成。结果表明，MGDG中主要含有16：0，18：3,18：2以及少量20：4和20：5。MGDG中Sn-2位80％多为饱和脂肪酸16：0，Sn-1位57％以上为18：3。根据HPLC分离纯化所得7种主要组分的百分含量和Sn-1和Sn-2位脂肪酸的分析计算可得。MGDG主要脂肪酸分子组成为43．6％(18：3，16：0)，13．9％(16：0,16：0)，9．9％(18：2，16：0)，8．9％(18：3，16：1)。 相似文献
11.
Chandralata Raghukumar G. Sheelu P. A. Loka Bharathi Shanta Nair C. Mohandass 《Marine Georesources & Geotechnology》2001,19(1):1-16
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance. 相似文献
12.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
13.
Derek V. Ellis 《Marine Georesources & Geotechnology》2001,19(1):51-63
This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested. 相似文献
14.
G. Parthiban 《Marine Georesources & Geotechnology》2000,18(3):223-235
Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement. 相似文献
15.
Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification
An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm. 相似文献
16.
海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。 相似文献
17.
The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments. 相似文献
18.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
19.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
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