低盐度突变对中国对虾仔虾存活率的影响   总被引：5，自引：0，他引：5  

马英杰  张志峰  马爱军  廖承义  孙谧 《海洋与湖沼》1999,30(2):134-138

１９９６年３－４月在山东日照市代家村对虾育苗场采集中国对虾仔虾,采用实验室培养的方法,研究中国对虾仔虾对不同低盐度突变的幅度及速率的适应能力,并对在不同盐度突变后仍能存活的仔虾体内的１８种氨基酸、１４种脂肪酸及５种维生素的含量作了分析比较。结果表明,当降盐的工范围为３／ｄ－５／ｄ时,部分仔虾可在盐度为零的淡水中存活数天。盐度的变化对仔虾体内氨基酸,脂肪酸和维生素的含量均有一定影响。  相似文献   

黑海参脂肪酸的气相色谱／质谱法分析          下载免费PDF全文

楼乔明  王玉明  薛长湖  徐杰  杨文鸽  李国云 《海洋科学》2011,35(6):35-38

黑海参（Holothuria atra）体壁经Folch法提取总脂,用HCl-甲醇进行甲酯化处理,以气相色谱／质谱法分析总脂中的脂肪酸组成。从黑海参中共分析出28种化合物,包括25种脂肪酸甲酯和3种脂肪醛二甲基缩醛。黑海参体壁中的饱和脂肪酸含量为22．93％,以C16：0（5．49％）和C18：0（4．38％）为主;不...  相似文献   

超声波对湛江等鞭金藻生长和脂肪酸组成的影响   总被引：5，自引：0，他引：5  

李文权  王宪  陈清花  张元标  翁蓁洲 《海洋学报》2002,24(3):94-100

设计了一个超声频率、超声功率和处理时间三因素四水平的正交实验,研究了超声波对湛江等鞭金藻的生物学效应.实验结果表明,超声频率对湛江等鞭金藻的生物学效应显著,而超声功率和处理时间的影响相对较小.对于提高湛江等鞭金藻生长速率常数,最佳超声条件为20kHz,6W,10s3次;对于提高其脂肪酸不饱和度和主要不饱和脂肪酸百分比,最佳超声条件为20kHz,4～6W,30s.在最佳超声条件下,湛江等鞭金藻生长速率常数最高可达0.630d,是对照组的2.02倍,其脂肪酸不饱和度最高可达79.6%,比对照组提高7.8%,其中主要不饱和脂肪酸的百分含量均得到不同程度的提高.  相似文献   

中国黄、渤海常见大型海藻的脂肪酸组成   总被引：8，自引：3，他引：8  

李宪璀  范晓  韩丽君  严小军  娄清香 《海洋与湖沼》2002,33(2):215-224

对中国黄、渤海沿岸的17种红藻、12种褐藻、7种绿藻的脂肪酸组成进行了分析研究，结果表明，黄海和渤海的绝大多数红都富含二十碳高度不饱和脂肪酸（主要是二十碳五烯酸，EPA和二十碳四烯酸，AA），一般都占总脂肪酸的40％以上；仙菜目的松节藻、细枝软骨藻，隐丝藻目的亮管藻、海萝、海膜、蜈蚣藻中的EPA含量均超过40％，其中海萝达到58％；杉藻目扁江蓠中EPA含量很低，但花生四烯酸含量达到58％。裸藻中16：0、18：1（n-9)、20：4（n-6)和20：5（n-3)含量占绝对优势，十八碳高度不饱和脂肪酸（PUFAs)和二十碳PUFAs是主要的脂肪酸。在每种褐藻中还含有一定量的14：0、18：2（n-6)和18：4（n-3)。褐藻中的十八碳PUFAs含量比红藻高，而二十碳PUFAs比红藻低。绿藻中的主要脂肪酸是16：0、十六碳高度不饱和脂肪酸（主要是：16：4（n-3)和16：3（n-3)、18：1以及C18PUFAs（主要包括18：2（n-6),18:3(n-3)和18：4（n-3)，绿藻的C16、C18PUFAs含量较高。  相似文献   

脂类分析在海洋微藻化学分类学上的研究进展   总被引：8，自引：0，他引：8  

徐继林  严小军 《海洋通报》2004,23(2):65-72

总结了目前脂类研究在海洋微藻化学分类学上的研究进展。所有的海洋微藻脂类都含一定的脂肪酸和甾醇,而不同种类的海洋微藻都有其特殊的脂肪酸和甾醇组成特征,我们可以运用这些特性来判别微藻可能所处的化学分类学地位：如果运用从某些藻类中发现的部分罕见脂类成分,还有可能对微藻的个别种类进行确定。随着对微藻中脂类物质分离,提取、纯化技术研究的不断深入,加上质谱、核磁共振等结构分析手段和脂类衍生化技术的日益完善,可以构建海洋微藻脂类物质组成结构快速查询信息库,并使其成为微藻化学分类的一个重要辅助手段。  相似文献   

Soldier crab (Dotilla myctiroides) distribution,food resources and subsequent role in organic matter fate in Ao Tang Khen,Phuket, Thailand     

Kimberly K. Takagi  Phaothep Cherdsukjai  Izumi Mimura  Yuka Yano  Kanjana Adulyanukosol  Makoto Tsuchiya 《Estuarine, Coastal and Shelf Science》2010

This study aimed to elucidate Dotilla myctiroides (H. Milne-Edwards) food resources and how the soldier crab influences the organic matter composition on the intertidal flat. A preliminary assessment of D. myctiroides size, sex, and population distribution was conducted to clarify the characteristics of the inhabiting population. Overall, D. myctiroides size and abundance was normal across the tidal flat area. Comparison of different sediment types from the soldier crab habitat (surface sediments, igloos, burrow lining, burrow pellets, feeding pellets, and feces) using the fatty acid (FA) analysis technique revealed D. myctiroides removes organic matter via the significantly lower contributions of polyunsaturated FAs, essential FAs, and dinoflagellates in the feeding pellets. Dotilla myctiroides tissue analysis of the hepatopancreas and hindgut in individuals that had been starved for 24 h confirmed not only the consumption of dinoflagellates, but diatoms and macroalgae as well. In addition, the FA metabolism within the digestive system implied the ability of the soldier crab to synthesize highly unsaturated FAs (HUFAs) such as 20:4n–6, 20:5n–3 and 22:6n–3.  相似文献   

LMWOA (low molecular weight organic acid) exudation by salt marsh plants: Natural variation and response to Cu contamination     

Ana P. Mucha  C. Marisa R. Almeida  Adriano A. Bordalo  M. Teresa S.D. Vasconcelos 《Estuarine, Coastal and Shelf Science》2010

This work aimed to evaluate, in vitro, the capability of roots of two salt marsh plants to release low molecular weight organic acids (LMWOAs) and to ascertain whether Cu contamination would stimulate or not organic acids exudation. The sea rush Juncus maritimus and the sea-club rush Scirpus maritimus, both from the lower Douro river estuary (NW Portugal), were used. Plants were collected seasonally, four times a year in 2004, during low tide. After sampling, plant roots were washed for removal of adherent particles and immersed for 2 h in a solution that matched salinity (3) and pH (7.5) of the pore water from the same location to obtain plant exudates. In one of the seasons, similar experiments were carried out but spiking the solution with different amounts of Cu in order to embrace the range between 0 and 1600 nM. In the final solutions as well as in sediment pore water LMWOAs were determined by high performance liquid chromatography. Plants were able to release, in a short period of time, relatively high amounts of LMWOAs (oxalate, citrate, malate, malonate, and succinate). In the sediment pore water oxalate, succinate and acetate were also detected. Therefore, plant roots probably contributed to the presence of some of these organic compounds in pore water. Exudation differed between the plant species and also showed some seasonally variation, particularly for S. maritimus. The release of oxalate by J. maritimus increased with Cu increase in the media. However, exudation of the other LMWOAs did not seem to be stimulated by Cu contamination in the media. This fact is compatible with the existence of alternative internal mechanisms for Cu detoxification, as denoted by the fact that in media contaminated with Cu both plant species accumulated relatively high amounts (29–83%) of the initially dissolved Cu. This study expands our knowledge on the contribution of globally dominant salt marsh plants to the release of LMWOAs into the environment.  相似文献   

冷冻牡蛎贮存过程中脂溶性有毒物质的变化研究     

张宁  林洪  隋涛  钟响  张艺兵  刘峰 《中国海洋大学学报(自然科学版)》2010,40(1)

牡蛎是我国出口量较大的水产品之一,由于产品本身的特殊性,在生长过程中易产生腹泻性贝毒(DSP).本实验中原料牡蛎DSP生物法检测结果为阴性,冷冻贮存4个月后检测结果即为阳性.本研究以分析这一变化原因为目的,采用LC-MS法对DSP生物检测的阳性样品进行确认,结果表明,生物法DSP检测的结果为假阳性,造成生物法DSP检测中小白鼠死亡的是牡蛎在贮藏过程中产生的脂溶性有毒物质.进一步分析确定该有毒物质为牡蛎脂肪水解物--游离脂肪酸.同时本研究对牡蛎在不同贮存温度和贮存时间下产生的游离脂肪酸含量进行了测定,在-10 ℃贮存温度下,贮存0,2,4,6,8,10个月,游离脂肪酸的变化范围为5.2～788.6 mg/kg;在-10 ℃,-18 ℃,-25 ℃贮存温度下,贮存4个月,游离脂肪酸的变化范围为92.5～389 mg/kg.  相似文献   

The molecular composition of ambers     

J.O. Grimalt  B.R.T. Simoneit  P.G. Hatcher  A. Nissenbaum 《Organic Geochemistry》1988,13(4-6)

Bulk (elemental composition, IR, CP/MAS ¹³C NMR) and molecular (GC-MS) analyses have been performed on a series of ambers and resins derived from different locations (Dominican Republic, Philippines, Canada, Israel, New Zealand, Chile) having diverse botanical affinities (Araucariaceae, Hymenaea) and variable age (from Holocene to Early Cretaceous). No major differences have been observed from the elemental composition and the spectroscopic data; however, the molecular analyses of the solvent extractable fraction show that a specific mixture of components is present in each sample. These are mainly diterpenoid products that in general are also found abundantly in the higher plants from which the ambers and resins originate. Nevertheless, a direct relationship between major terpenoid constituents in fossil resins and precursor plant materials can only be established for the younger samples.Irrespective of the geographical or botanical origin of the ambers and resins, several common age-dependent molecular transformation trends can be recognized: (1) progressive loss of olefinic bonds (especially those located in exocyclic positions), (2) decrease of functionalized products, and (3) increasing proportion of aromatized components. However, even in the samples of older age (Cretaceous) the degree of aromatization is very low when compared with that of other higher-plant related materials such as fossilized woods or low rank coals. This indicates that maturation must involve essentially olefin polymerization processes instead of extensive aromatization.  相似文献   

Amino acid nitrogen in atmospheric aerosols: Occurrence,sources and photochemical modification   总被引：2，自引：0，他引：2  

Peter J. Milne  Rod G. Zika 《Journal of Atmospheric Chemistry》1993,16(4):361-398

The presence of amino acids in atmospheric precipitation and aerosols has been noted for many years, yet relatively little is known about these or other nitrogen containing organic compounds in the atmosphere. Marine and continental rainwater analyses indicate that atmospheric aerosols, and subsequently atmospheric precipitation, may contain substantial levels of free and combined amino acids. The most likely source of amino N in the remote marine atmosphere appears to be the injection of proteinaceous material through the action of bursting bubbles at the sea-air interface or the long range transport from terrestrial sources. The capacity of these substrates to undergo photooxidation and photodegradation in the atmosphere to simpler species, such as ammonium ions, carboxylic acids, and for the S containing amino acids, oxidized forms of sulfur, has received little attention from atmospheric chemists. The photochemistry of covalently bound amino groups, particularly as found in peptides and amino acids, is discussed here with the purpose of summarizing what is known of their occurrence and their possible importance to atmospheric chemistry.  相似文献