2014 Fiscal Year Final Research Report
Estimation of Organic Carbon Content of the Cyanobacterium by Soft X-ray Microscopy
Project/Area Number |
24510039
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Environmental impact assessment/Environmental policy
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Research Institution | Kansai Medical University |
Principal Investigator |
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Co-Investigator(Renkei-kenkyūsha) |
YAMAMOTO Akitsugu 長浜バイオ大学, バイオサイエンス学部, 教授 (30174775)
IKEGAYA Hisato 兵庫県立大学, 理学部, 客員研究員 (30531579)
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Research Collaborator |
ICHISE Satoshi 滋賀県琵琶湖環境科学研究センター, 環境監視部門, 専門員
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Project Period (FY) |
2012-04-01 – 2015-03-31
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Keywords | 軟X線顕微鏡 / 微細シアノバクテリア / 細胞外代謝産物(EPS) / Synechococcus sp. / 有機物量評価 / X線マイクロCT |
Outline of Final Research Achievements |
Phytoplankton typically produces large amounts of extracellular polysaccharides (EPS), which is mainly composed of macromolecular heteropolysaccharides. As EPS contains large quantities of organic matter, it may be a major contributor to the increased COD in Lake Biwa. To confirm this speculation, a method for the accurate evaluation of the organic carbon (OC) content of phytoplankton by soft X-ray microscopy (XM) was developed and applied to Synechococcus sp. Soft XM is a non-destructive imaging technique that generates images based on differences in X-ray absorption by light elements, such as, carbon, oxygen, and nitrogen. Based on the X-ray absorption coefficients and gray levels of the XM images, the OC content of EPS-covered cells (0.39-0.47 pg/cell) was found to be 2.0-2.4 times larger than that of EPS-removed cells (0.20 pg/cell). These findings suggest that soft XM could be a useful tool for evaluating the OC content of picophytoplankton and EPS without pretreatment steps.
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Free Research Field |
X線顕微鏡学
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