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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
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
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Franois Gelin Ilco Boogers Anna A. M. Noordeloos Jaap S. Sinninghe Damste Roel Riegman Jan W. De Leeuw 《Organic Geochemistry》1997,26(11-12)
Non-hydrolysable macromolecular constituents (i.e. algaenans) were isolated from two out of seven marine microalgae investigated. Nannochloropsis salina and Nannochloropsis sp. from the class of Eustigmatophyceae produce highly aliphatic algaenans. Flash pyrolysis and chemical degradations with HI and RuO4 allowed for the identification of their chemical structure, which is mainly composed of polyether-linked long-chain (up to C36) n-alkyl units. The building blocks of this polymer were also recognized in lipid fractions. The green microalgae (Chlorophyceae) Chlorella spaerckii, Chlorococcum sp. and Nannochloris sp. were earlier thought to biosynthesize algaenans comprising aliphatic and/or aromatic moieties. However, a new isolation method utilizing trifluoroacetic acid (TFA) prior to the other hydrolyses revealed that the macromolecular material isolated from these three chlorophytes was either hydrolysable with TFA or artefacts from the former method. Similar to algaenans from fresh water green microalgae, the aliphatic eustigmatophyte algaenans are likely to be selectively preserved in depositional environments and might ultimately serve as source rock organic matter of marine crude oils. Furthermore, they may play an important role in the cycling of carbon. 相似文献
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Abstract. The interrelationships between the main phytobenthic groups of Chlorophyceae, Phaeophyceae, and Rhodophyceae around Milos Island, Central Aegean Sea, were studied using standard ecological and mathematical methods. The analysis was based on seasonal sampling of 114 different macrophytobenthic species.
The employed ecological indices revealed that the sampling areas located on the north, south, and east side of Milos Island show similar annual fluctuations in abundance and species diversity. The resemblance was particularly high between all stations in October-February, between south and east stations during May, and between north and east stations during July.
Additionally, an annual cycle of group interaction with regard to species diversity and abundance exists between the Chlorophyceae, Rhodophyceae, and Phaeophyceae. The Rhodophyceae are the most abundant and dominant group throughout the year, showing percentages in the samples higher than 70% in all sampling areas. 相似文献
The employed ecological indices revealed that the sampling areas located on the north, south, and east side of Milos Island show similar annual fluctuations in abundance and species diversity. The resemblance was particularly high between all stations in October-February, between south and east stations during May, and between north and east stations during July.
Additionally, an annual cycle of group interaction with regard to species diversity and abundance exists between the Chlorophyceae, Rhodophyceae, and Phaeophyceae. The Rhodophyceae are the most abundant and dominant group throughout the year, showing percentages in the samples higher than 70% in all sampling areas. 相似文献
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Lake Baikal, an ancient pristine lake in Siberia, has accumulated sediment deposits that span 25 million years. These deposits
have the potential to provide a long-term record of climate changes and their interaction with the ecology of the lake. In
order to investigate whether sedimentary phytoplankton pigments could be used to reconstruct past changes in total phytoplankton
abundance and productivity, we compared the spatial variability in sedimentary pigment distributions in Holocene cores from
three separate regions of the lake; Vidrino in the south, Posolski on Selenga Delta and Continent Ridge in the north. Furthermore,
we present the first continuous sedimentary pigment and organic carbon sequence of the Kazantsevo interglacial (roughly a
time equivalent to the European Eemian, and Marine Isotopic Stage MIS5e) at a resolution of approximately 150 years. Results
of the spatial study showed marked differences in the sediment pigment deposition. Lowest chlorophyll a plus its degradation products versus organic carbon ratios (Chlas/TOC) indicating lowest production, but highest variability with time (indicating strongest climatic oscillations) were found
at Continent Ridge. The study of sedimentary pigments deposited during the last two interglacial periods at Continent Ridge
showed Chlas/TOC ratios 50–1000 times higher during the Kazantsevo Interglacial compared to the glacial periods, whereas the TOC content
was only five times higher, thus indicating the significance of the Chlas/TOC ratio for the reconstruction of the phytoplankton abundance and productivity. Strong oscillations occurred during the
Kazantsevo Interglacial within centennial time scales. Chlorophyllb plus its degradation products provided additional information on the past development of Chlorophyceae. Highest Chlas/TOC ratios were found during the early Holocene at approximately 9 kyr BP. Indications of short phytoplankton production
maxima were also found during the late Atlantic (6 kyr BP) and at the Subboreal/Subatlantic transition (3 kyr BP). From this
we conclude that sedimentary chlorophyll a is a reliable indicator of phytoplanktonic response to climate changes and may serve for␣validation of future climate scenarios
in continental regions. 相似文献
5.
In the eustigmatophycean Nannochloropsis limnetica the content of polyunsaturated fatty acids (PUFA) is extremely high in comparison to different planktonic green algal taxa in freshwater ecosystems. The sums of n-6 and n-3 fatty acids in N. limnetica were ten-fold higher than in the other picoplankton Choricystis minor and Pseudodictyosphaerium jurisii, and higher than in the nanoplanktonic green algae Chlorella vulgaris, Monoraphidium neglectum and Scenedesmus obtusiusculus. The content of fatty acids in N. limnetica was highly variable under different culture conditions. The highest concentrations of PUFA in N. limnetica were found in non-aerated suspension cultures, with a high content of phosphate (40 mg l−1 K2HPO4) in the culture medium: linoleic acid 22.19 mg g−1 DW, arachidonic acid 10.52 mg g−1 DW, and eicosapentaenoic acid 55.56 mg g−1 DW. N. limnetica represent a high-quality food resource in freshwater food chains. Furthermore, cultures of this eustigmatophycean alga have a high potential for use in biotechnology and aquaculture. 相似文献
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