1997 Fiscal Year Final Research Report Summary
Development of utilization of lipid containing polyunsaturated fatty acids produced by microbes.
| Project/Area Number |
08455384
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
生物・生体工学
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| Research Institution | HIROSHIMA UNIVERSITY |
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Principal Investigator |
SUZUKI Osamu Hiroshima University, Faculty of Engineering, Professor, 工学部, 教授 (00274126)
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| Co-Investigator(Kenkyū-buntansha) |
AKI Tsunehiro Hiroshima University, Faculty of Engineering, Research Associate, 工学部, 助手 (80284165)
SHIGETA Seiko Hiroshima University, Faculty of Engineering, Associate Professor, 工学部, 助教授 (10034381)
ONO Kazuhisa Hiroshima University, Faculty of Engineering, Professor, 工学部, 教授 (10144883)
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| Project Period (FY) |
1996 – 1997
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| Keywords | Polyunsaturated fatty acid / Docosahexaenoic acid / Arachidonic acid / DELTA6 Desaturase / Allergy / Lipid |
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| Research Abstract |
An isolated fungus Mortierella alliacea YN-15 had a capable of producing 3.9 g/L of arachidonic acid in a flask and 5.0 g/L in a jar fermentor. This strain could metabolize soluble starch as well as glucose. We isolated another arachidonic acid producing microbe Achlya sp.ma-2801 which also contained a significant amout of eicosapentaenoic acid in the cell. Eight stains of microbes producing docosahexaenoic acid were isolated from the sea and one of them, by cultivation in a jar fermentor, appeared to contain high amount of phospholipids consisted of docosahexaenoic acid. A mutant strain MS14-13 that produced higher level of docosahexaenoic acid was isolated from a strain Schizochytrium sp.SR21. The mutant showed higher content of docosahexaenoic acid in total fatty acid than of wild type strain. A gene encoding delta-6 desaturase has been cloned from blue algae and expressed functionally in yeast resulting a successful conversion of exogenious linoleic acid into gamma-linolenic acid.
We found, in analyzes of serum fatty acid compositions of allergic patients, RAST value of indivisual patients had a positive correlation with linoleic acid content in their plasma lipid, suggesting the depressed activity of delta-6 desaturase in allergic patients.
It is considered that the manipulation of multi-enzyme system of fatty acid desaturation and chain elongation is neccessary for breeding of microbes producing polyunsaturated fatty acids. Isolation of mutants defective in desaturase enzymes and/or cloning of genes coding for such enzymes would be indispensable.
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