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1.
本文讨论了用90%丙酮从海藻中提取叶绿素进行测定的三种提取方法(研磨法、浸泡提取法、超声波粉碎法)的最佳条件。并对三种提取方法的提取效率进行了比较。结果表明研磨法的提取效率较高,样品可立即测定,是一种较好的提取方法。本文还讨论了不同离心力对叶绿素测定的影响。实验表明使用离心力为2000g的LXJ-64-01型离心机可基本满足测定要求。  相似文献   

2.
采用Mini-Beadbeater组织研磨器破碎的方法进行了提取霞水母刺丝囊细胞毒素的研究。首先制备霞水母刺丝囊细胞,然后研究破碎频率、破碎时间对提取霞水母刺丝囊细胞毒素浓度的影响。结果表明,组织研磨器能够在2—3min内破碎约90%的霞水母刺丝囊细胞,从而提高水母毒素的提取效率。SDS-PAGE结果显示,提取的水母毒...  相似文献   

3.
朱乾坤  冯旗  尹中林  郑亲波  潘德炉 《台湾海峡》2001,20(4):420-425,T001
本文首先介绍了由中国科学院上海技术物理研究所最新研制的海洋多波段扫描仪(OMS)的性能和特色,并描述了1999年10月份在黄渤海典型海区进行航空校飞的实验的概况及校飞资料的处理过程。然后,针对不同海区的水色特点,着重探讨了通过最佳通道选择进行假彩色合成叶绿素的定性提取法和模式计算的定量提取法的原理和方法。最后,通过航空校飞、卫星遥感和实测三种准同步资料所得叶绿素浓度空间分布的趋势比较验证了两种叶绿素提取方法和可信度,同时也显示了在OMS基础上所研制的我国第一颗海洋水色卫星水色遥感器的应用前景。  相似文献   

4.
采用匀浆法、冻融温差法、超声波法、直接研磨法和低温研磨法等5种破壁方法,研究了雨生红球藻提取虾青素时破壁方法对虾青素提取率的影响。结果表明,对雨生红球藻进行破壁是必要的。其中匀浆法、冻融温差法、超声波法、直接研磨法和低温研磨法等的最佳破壁条件为:匀浆法破壁时间22min,水为介质;冻融温差法破壁温度为-70℃,时间为12h,冻融2次,水为介质;超声功率400W,每次超声时间5s,共超声25min;直接研磨法研磨时间1min;加液氮低温研磨法破壁2次,每次时间0·5min;虾青素的提取率依次为0·76%、0·93%、1·03%、1·51%和3·21%。匀浆法和超声波法破壁由于要使用溶剂或介质,对后续的虾青素提取和分离会有影响,而直接研磨法在破壁过程中产生高温,降低了虾青素的生理活性,所以它们都不是雨生红球藻破壁的最佳方法。加液氮低温研磨法在破壁过程中不添加化学试剂,不产生污染,能最大限度地保留虾青素的生理活性,是所选方法中最好的一种。  相似文献   

5.
一种新的叶绿素高效萃取剂及其应用方法   总被引:2,自引:0,他引:2  
叶绿素是海洋生态学调查中必不可少的检测项目,也是反映浮游植物生物量乃至初级生产力水平的最简便而有效的指标。叶绿素测定的关键环节在于将叶绿素从细胞中有效地提取出来,因而选择适当的萃取剂是致关重要的。以往报道的萃取剂有;乙醇、乙酸、两酮等。其中,以丙酮最为常用。这些萃取剂都存在一些缺点,如:提取时间长、提取过程中叶绿素a会降解、提取不完全,以及操作烦琐(如研磨、离心)等(Suzuki&Fujita,1986;Porra et al,,1989;Suzuki&Ishimaru,1990)。为找到一种更…  相似文献   

6.
鱼饲料着色剂-甲壳类下脚料类胡萝卜素的提取技术   总被引:6,自引:0,他引:6  
本文对近40年来甲壳类下脚料中类胡萝卜素的提取技术进行了综述,其提取技术流程主要包括:1.下脚料预处理。下脚料研磨后经2mm筛网去除几丁质残渣,或研磨后直接提取;2.热醋酸、盐酸的直接去钙化或酸青贮(有机酸及无机酸)去钙化;3.添加蛋白酶进行水解;4.类胡萝卜素的油提取及化学提取。三个阶段批逆流加工法及有机溶剂(丙酮、己烷、石油醚)提取类胡萝卜素5.类胡萝卜素稳定性控制。在整个处理工艺的某阶段添加  相似文献   

7.
邵慧敏  王聪  汪辉  刘天中 《海洋科学》2018,42(2):118-123
利用代谢物组学技术有助于更为深入地了解不分枝丝状微藻黄丝藻细胞的生物学特性。本研究比较了3种黄丝藻细胞破碎方法(冻融法、超声破碎法、液氮研磨法)以及基于气相色谱-质谱联用技术的3种黄丝藻代谢物提取系统(冷甲醇、热乙醇、甲醇/氯仿法),以期为黄丝藻细胞的代谢组学分析奠定基础。结果显示:液氮研磨法处理下的黄丝藻细胞破碎效果最佳;根据提取到的代谢物的种类角度出发,冷甲醇法的提取效果要明显优于其他2种提取方法。在黄丝藻细胞中共检测到40种代谢物,包括9种氨基酸、17种有机酸、12种糖类和2种醇类物质。  相似文献   

8.
黄、东海柱状沉积物中生物硅含量的分析   总被引:15,自引:0,他引:15  
对东、黄海2 0 0 0年10月和2 0 0 1年5月2个航次所获得的表层及柱状沉积物样品进行分析,在单点提取测定方法的基础上采用连续提取方法,利用斜率校正法扣除非生物硅的干扰,测定了东、黄海柱状沉积物中生物硅的含量。从整个东、黄海海域来看,沉积物中生物硅的含量<1% ,属于低含量海域;讨论了沉积物样品处理方法对分析结果的影响,在此基础上分析了不同海区柱状沉积物中生物硅的分布特征以及沉积物中叶绿素、水体中硅酸盐、叶绿素、N/P比值等生态要素与沉积物中生物硅分布的相关关系。  相似文献   

9.
南海中部叶绿素a分布和光合作用及其与环境因子的关系   总被引:2,自引:0,他引:2  
本文描述了1983年9月—1984年12月4个航次南海中部(12°—19°30′N,111°—118°E)综合调查期间有关叶绿素a和光合作用的测定结果,并对叶绿素a时空分布,光合作用及其与环境因子的关系进行了讨论。调查表明:次表高值层为叶绿素分布的一个特征,其深度在50—100m左右,含量范围多在0.1—0.6mg/m~3之间。叶绿素a的垂直变化与温、盐跃层,营养盐以及光的分布有关,而垂直积分的总量平面分布则与不同水团的消长有关。光合作用随深度的变化说明某些浮游植物适于低光下生长,而这些生物的活动也影响着亚硝酸盐和溶解氧的生成。  相似文献   

10.
底栖绿藻叶绿素的二甲基亚砜提取和测定法   总被引:3,自引:0,他引:3  
以缘管浒苔(Enteromorpha linza(L.)J.Ag.)、孔石莼(Ulva pertusa Kjellm)和袋礁膜(Monostroma angicava Kjellm)三种底栖绿藻为材料,用二甲基亚砜(DMSO)/80%。丙酮(1/2,v/v)作溶剂,提取和测定其叶绿素含量,并同广泛应用的以80%丙酮为溶剂的Arnon法作了比较,所得主要结果如下。1.等量色素的DMSO/80%丙酮溶液的叶绿素,其红光吸收峰略高于80%丙酮溶液的吸收峰。用作定量测定的三个波长,即663,652和645nm的吸光率分别比80%丙酮溶液高6,7和8%。2。在DMSO/80%丙酮和80%丙酮中,叶绿素的稳定性相同。3.用DMSO/80%丙酮混合溶剂提取底栖绿藻的叶绿素的优点是,可用藻体直接提取,而且提取速度比用80%丙酮时要快。  相似文献   

11.
研究不同提取方法对中国对虾肌肉提取物中含氮化合物组成和含量的影响。以TCA、PCA、SSA和AL法沉淀蛋白质后得到对虾肌肉提取物中总氮量分别为833、878、840和701mg·N/100g。前三种方法处理的提取物中游离氨基酸总量相近,而结合氨基酸含量相差甚大。TCA法和AL法对肌肉提取物中大分子化合物沉淀效果较好。提取对虾肌肉中的核着酸以TCA、SSA法较好。氧化三甲胺和甜菜碱含量分别为80~100mg/1009和300~320mg/100g之间,TCA、PCA、SSA三法比较接近,而AL法明显偏低。提取物中含氮化合物的分布为:游离和结合氨基酸氮占71~78%,核苷酸类氮占9~11%,甜菜碱氮占3~5%,氧化三甲胺占1~2%。  相似文献   

12.
海水溶解有机物(dissolvedorganicmatter,DOM)中含有的生物活性物质在海洋生态系统中作用巨大,但因缺乏适合的分离提取方法而严重阻碍了对其不同组分在生态系统中作用的探索。固相萃取法对富集提取海水DOM十分有效,在用其提取海水DOM时,海水pH对活性物质提取效果的影响很大,但目前针对海水的这种影响尚存在很大争议。本文以天然近海海水作为基质,探究不同pH条件下用亲水-疏水平衡(hydrophilic-lipophilicbalanced,HLB)固相萃取小柱萃取海水中活性分子的提取效率,并使用高效液相色谱-四极杆飞行时间质谱(HPLC-Q-TOF-MS)在负离子(ESI-)模式下检测解析提取物的组成。研究结果表明,当海水样品pH为中性和强酸性时都能获得较好的提取效率,随着pH的降低,提取物质谱的整体响应值降低,但可识别的谱峰数目增加,提取出有机物的分子量和性质差异都更广泛。分析提取物分子在范克雷维伦(van Krevelen)图和质荷比-氢碳比(m/z-H/C)图上的分布发现,中性条件适合提取饱和度较高的小分子化合物,而具有生物活性的带有不饱和基团的化合物及蛋白质、糖类等生物大分子在强酸性提取条件时提取效果和分辨率更好。综合提取效率、有效峰数目和分子组成特征考虑,用HLB固相萃取小柱提取近海海水中的小分子活性物质时,将海水样品pH调节为2较为适宜。  相似文献   

13.
本文建立了半透膜渗透装置(semi-permeable membrane device,SPMD)富集-超声萃取-凝胶渗透色谱净化-气相色谱法测定沉积物间隙水中多氯联苯(PCBs)的方法。比较了有机溶剂透析法与超声萃取法从膜袋内提取PCBs的回收率,发现超声萃取法在节省时间和溶剂方面有明显优势。应用凝胶渗透色谱分离与净化SPMD提取物,收集11—17min的流出液能达到最佳分离效果。基于此方法测定了大连湾沉积物间隙水中自由溶解态PCBs的含量(C_(W-SPMD)),同时又分析了沉积物中PCBs的总量(C_(SED))、间隙水中PCBs的含量(有机碳含量校正法,C_(W-SED))和间隙水中PCBs的总含量(离心法,C_(PW))。结果表明,C_(PW)值显著高于C_(W-SED)和C_(W-SPMD)值。因此,考虑到生物可利用性,无论采用沉积物中或者间隙水中的PCBs总量进行污染物生态风险评价均会造成风险被高估,建议采用间隙水中可溶解态含量。  相似文献   

14.
Existing methods for analyzing methylsulfonyl-PCBs in animal tissues require multiple laborious clean-up steps prior to quantitation. In this paper, we report a new, efficient method for the isolation and determination of methylsulfonyl-PCB metabolites in the blubber, liver, kidney, lung, and milk from mammals of marine origin using: solvent extraction, GPC fractionation, and clean-up on an adsorption chromatography column prior to analysis by gas chromatography-mass spectrometry. The method is rapid and can be completed in about half the analysis time required by most other reported methods. The method exhibits excellent analyte recoveries (89-95%), and good reproducibilities with CV's ranging from 3-12% depending on analyte concentration. Detection limits are approximately 1 ng/g lipid. The method is further validated by comparing its quantitative results to that of an independent reference analytical method for several different marine mammal blubber samples. Finally, the method is applied to profile the distribution of methylsulfones among the various tissue types studied for a single bottle-nose dolphin (Tursiops truncatus) sample. In addition, the extent of their transplacental transfer from mother to unborn fetus for several pilot whale (Globicephala melaena) mother-fetus pairs is examined.  相似文献   

15.
黄土中游离氧化铁是指示夏季风的替代性气候指标之一。使用经典的CBD法提取游离氧化铁实验过程烦琐,而且实验条件不同对浸提结果影响很大。本实验采用盐酸羟胺-盐酸体系在不同的温度下浸提黄土中的游离氧化铁。实验结果表明:温度对实验结果影响最大,盐酸浓度次之。与经典的CBD法进行对比,在一定的条件下可以代替CBD法,从而简化试验。  相似文献   

16.
The characterization of solid phase-associated transition metals is important in understanding solid—seawater interactions. This has proven to be a difficult problem because of the complex nature of most sediments and suspended particulate matter. Many chemical techniques have been proposed to describe sedimentary metal phases. Most rely on characterizing equivalent chemical reactivities from the various metal phases rather than the characterization of the actual physical phases with which the metals are associated. In this study, several of the most widely used trace metal extraction techniques are compared for many of the most commonly measured transition metals using a variety of naturally occurring major marine sediment types. All solid concentrations are normalized to total metal values as obtained by neutron activation and X-ray fluorescence analyses.One weak, four intermediate strength, and two strong metal extraction methods were studied individually. The weak method had the lowest degree of extraction efficiency, but dissolved all solid carbonate phases. Its probable inability to retain released metals quantitatively in solution is a major problem. Three of the four intermediate methods are similar. The other and simplest of the four methods (0.5 N HCl), released much lower amounts of most metals studied when compared to these other three. It cannot be classified as a weak method, however, as it does attack some moderately resistant solid phases. Only one of the other three intermediate methods (a reducing acetic acid solution), was relatively free from analytical difficulties and it is preferred for this reason. The two strong extraction methods are quite similar, with neither yielding total metal concentrations.A five-step sequential extraction scheme was also evaluated. The results were generally quite good, both with regard to metal phase fractionation and overall total extraction of available metals. Based on the results of this study, a sequential extraction scheme is a useful method for characterizing solid phase-associated transition metals.  相似文献   

17.
微藻总脂含量测定方法概述   总被引:1,自引:0,他引:1  
概述微藻总脂含量测定方法的研究现状并比较各方法的优缺点:(1)有机溶剂提取法使用较普遍、易操作、成本低,缺点是所需样品量大、所得总脂含量较低、溶剂有毒易污染环境、操作耗时费力;(2)索氏提取法测定微藻总脂含量较准确,缺点是所需试剂和样品量大,提取时间长;(3)荧光染料测定法、傅里叶变换红外光谱法、磷酸香草醛法、铜试剂法、苏丹黑染色法以及核磁共振法所需样品量少、所用时间短,但测定的总脂含量均为相对值.其中,荧光染料测定法不需要提取油脂且灵敏度高,但其易受各种因子影响;傅里叶变换红外光谱法和核磁共振法对样品无损伤,无需或仅需很少的预处理,后者重复性很好;磷酸香草醛法较稳定;铜试剂法成本低,但对其报道极少;苏丹黑染色法操作简单,不需要对藻细胞破碎及化学抽提,但不适用于不均匀样品的测定;(4)超临界CO2提取法和离子液体提取法提取效率高,所得总脂含量较高,但测定成本较高.  相似文献   

18.
Problems with biogenic silica measurement in marginal seas   总被引:5,自引:0,他引:5  
Surface sediment samples from the Bohai, Yellow Sea, and the Pacific were used to assess biogenic silica (BSi) content and to study uncertainties in BSi measurements. The contents of BSi in the Bohai and Yellow Sea are all less than 1%. The dissolution of BSi in sediments from the Bohai and Yellow Sea is very important to maintain high levels of silicate in the water column. The non-biogenic silica from clay minerals has an obvious effect on BSi of sediment samples in the Bohai and Yellow Sea with low BSi and high clay minerals. The solid to solution ratio was found to have a great influence on BSi measurement, which can induce uncertainties up to 75%. The effect of loss by sorption and centrifugation is negligible. Interlaboratory comparison of techniques for BSi measurement by the wet alkaline extraction technique of Mortlock and Froelich [Deep-Sea Res. 36 (1989) 1415-1426] with clay correction was suggested to give no significant differences. However, differences in sediment compositions and reagent to sample ratio may limit the application of the wet alkaline extraction method.  相似文献   

19.
Knowing the metal extraction capacity of a digestion method is crucial for a better environmental interpretation of metal concentrations determined in sediments. One of the main problems at the present is the lack of harmonization of information obtained by two of the most popular sediment partial digestion methods: ISO 11466.3 (aqua regia) and EPA 3050B (HNO?--H?O?--HCl). In the present work, the amount of Cu, Ni and Pb leached by using both methods was compared with the total content of those elements in marine sediments collected, as an example, from the Cienfuegos Bay, Cuba. Similar amounts of Cu were extracted by both methods; while leaching of Ni and Pb were different. Generally, the EPA method extracted more Ni than the ISO method. In contrast, Pb was extracted in a larger amount by the ISO method. Some explanations are given for the observed results. X-ray Diffraction, X-ray Fluorescence, Particle Induced X-ray Emission Spectrometry and Energy Dispersive X-ray coupled to Scanning Electron Microscopy were employed for this purpose. On the other hand, none of the methods studied extracted simultaneously the fraction of all the metals, probably provided by human activity (Theoretical Anthropogenic Fraction) in both sediments studied. The use of ISO 11466.3 or EPA 3050B is recommended since the analytical performance parameters of both, in combination with Flame Atomic Absorption Spectrometry, are adequate. For a better environmental interpretation of the analytical results, information on the extraction efficiency of the selected method for specific elements and sediments under study should also be provided, together with the determined concentrations.  相似文献   

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