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Shimizu Sakayu Akimoto Kengo Kawashima Hiroshi Shinmen Yoshifumi Yamada Hideaki 《Journal of the American Oil Chemists' Society》1989,66(2):237-241
The mycelial dihomo-γ-linolenic acid content of an arachidonic acid-producing fungus,Mortierella alpina 1S-4, was found to increase, with an accompanying marked decrease in its arachidonic acid content, on cultivation with sesame
oil. The resultant mycelia were found to be a rich source of dihomo-γ-linolenic acid. This unique phenomenon was suggested
to be due to specific repression of the conversion of dihomo-γ-linolenic acid to arachidonic acid by the oil. After fractionation
of the oil with acetone into oil and non-oil fractions, it was found that the effective factor(s) was present in the non-oil
fraction. In a study on optimization of the culture conditions for the production of dihomo-γ-linolenic acid byM. alpina 1S-4, a medium containing glucose, yeast extract and the non-oil fraction was found to be suitable for the production. Under
the optimal conditions in a 50-1 fermentor, the fungus produced 107 mg of dihomo-γ-linolenic acid/g dry mycelia (2.17 g/l
of culture broth). This value accounted for 23.1% of the total fatty acids in the lipids extracted from the mycelia. The mycelia
were also rich in arachidonic acid (53.5 mg/g dry mycelia, 11.2%). Other major fatty acids in the lipids were palmitic acid
(24.1%), stearic acid (7.0), oleic acid (20.1), linoleic acid (6.6) and γ-linolenic acid (4.1).
On leave from Suntory Ltd. 相似文献
2.
Sakayu Shimizu Kengo Akimoto Yoshifumi Shinmen Hiroshi Kawashima Michihiro Sugano Hideaki Yamada 《Lipids》1991,26(7):512-516
Incubation with sesame oil increases the mycelial dihomo-γ-linolenic acid content of an arachidonic acid-producing fungus,Mortierella alpina, but decreases its arachidonic acid content [Shimizu, S., K. Akimoto, H. Kawashima, Y. Shinmen and H. Yamada (1989)J. Am. Oil Chem. Soc. 66, 237–241]. The factor causing these effects was isolated and identified to be (+)-sesamin. The results obtained in experiments
with both a cell-free extract of the fungus and with rat liver microsomes demonstrated that (+)-sesamin specifically inhibits
Δ5 desaturase at low concentrations, but does not inhibit Δ6, Δ9 and Δ12 desaturases. Kinetic analysis showed that (+)-sesamin
is a noncompetitive inhibitor (Ki for rat liver Δ5 desaturase, 155 μM). (+)-Sesamolin, (+)-sesaminol and (+)-episesamin, also inhibited only Δ5 desaturases
of the fungus and liver. These results demonstrate that (+)-sesamin and related lignan compounds present in sesame seeds or
its oil are specific inhibitors of Δ5 desaturase in polyunsaturated fatty acid biosynthesis in both microorganisms and animals.
On leave from Suntory Ltd. 相似文献
3.
M Yasui J Kohmoto K Ota K Shinmen H Tanaka H Nogami 《Canadian Metallurgical Quarterly》1998,50(8):767-772
Histological findings and metal contents in the liver were studied in a patient with neurologic type of Wilson's disease. Copper and aluminum contents in the biopsied liver of the patient with Wilson's disease were measured simultaneously by neutron activation analysis at Research Reactor Institute, Kyoto University. Four cases of adult cirrhosis were selected as the control for cirrhosis and five cases of adult liver as the control for neurologically normal. The biopsied liver showed markedly increase in the copper content (814.4 micrograms/g: dry weight) and extremely high content of aluminum (479.4 micrograms/g: dry weight), compared to those of the controls. On the other hand, macroscopically no cirrhosis was observed and the characteristic appearances of macronodular cirrhosis failed to detect histologically. Interestingly the fibrosis or inflammation of the liver was seen faintly. It is likely that toxic metals in the liver such as aluminum, copper and manganese might be implicated in the pathogenesis of neurologic type of Wilson's disease. 相似文献
4.
Ikuo Ikeda Jun Murakami Takayuki Oka Michihiro Sugano Hideaki Yamada Sakayu Shimizu Hiroshi Kawashima Yoshifumi Shinmen Teruo Amachi 《Lipids》1991,26(1):27-30
The effects of perfused oleic (18∶1n−9), arachidonic (20∶4n−6) and 5,8,11,14-nonadecatetraenoic (19∶4n−5) acids on triglyceride
and cholesterol secretion and ketone body production were studied in isolated rat liver. As compared to oleic and 19∶4n−5
acids, both ketone body production and triglyceride secretion were significantly lowered when arachidonic acid was perfused.
The concentration of triglyceride in the post-perfused liver was lower upon perfusion with arachidonic acid than upon perfusion
with oleic acid or 19∶4n−5 acid. Cholesterol secretion in the liver perfused with arachidonic acid or 19∶4n−5 acid was significantly
higher than with oleic acid. The concentration of cholesterol in the post-perfused liver was slightly but significantly higher
with 19∶4n−5 acid than with the other fatty acids. The results suggest that 19∶4n−5 acid when compared with arachidonic acid
affects lipid metabolism in liver differently. 相似文献
5.
Sakayu Shimizu Hiroshi Kawashima Kengo Akimoto Yoshifumi Shinmen Hideaki Yamada 《Journal of the American Oil Chemists' Society》1989,66(3):342-347
Mycelia of arachidonic acid-producing fungi belonging to the genusMortierella were found to convert an oil containing α-linolenic acid to an oil containing 5,8,11,14,17-cis-eicosapentaenoic acid (EPA). This conversion was observed when they were grown in a medium containing the oil, glucose and
yeast extract at 28 C. On the screening of various oils, linseed oil, in which α-linolenic acid amounts to about 60% of the
total fatty acids, was found to be the most suitable for EPA production. Under the optimal culture conditions, a selected
strain,Mortierella alpina 20-17, converted 5.1% of the α-linolenic acid in the added oil into EPA, the EPA production reaching 1.35 g/l of culture
broth (41.5 mg/g dry mycelia). This value corresponded to 7.1% (by weight) of the total fatty acids in the extracted lipids.
The lipid was also found to be rich in arachidonic acid (12.3%). Other major fatty acids in the lipid were palmitic acid (4.4%),
stearic acid (3.2%), oleic acid (13.5%), linoleic acid (13.7%), α-linolenic acid (38.5%) and γ-linolenic acid (0.9%). 相似文献
6.
Sakayu Shimiziu Hiroshi Kawashima Yoshifumi Shinmen Kengo Akimoto Hideaki Yamada 《Journal of the American Oil Chemists' Society》1988,65(9):1455-1459
Mycelia of arachidonic acid-producing fungi belonging to the genusMortierella were found to be rich sources of 5,8,11,14,17-cis-eicosapentaenoic acid (EPA). Production of EPA by these fungi was observed
only when they were grown at low temperature (6–16 C). EPA comprised 5–20% of the total extractable mycelial fatty acids in
most strains tested. No significant accumulation of EPA was observed on incubation at high temperature (20–28 C), at which
the other major mycelial C-20 fatty acid, arachidonic acid, was still efficiently produced. In a study on the optimization
of the culture conditions for EPA production by a selected fungiM. alpina 20–17, a medium containing glucose and yeast extract as major carbon and nitrogen sources, respectively, was found to be
suitable. Periodic feeding of glucose during growth of the fungus and cultivation at high temperature (20 C) during the early
growth phase followed by temperature shift to 12 C were found to be effective at increasing mycelial yield and reducing cultural
period, respectively. Under the optimal culture conditions, the EPA production reached 0.49 mg/ml of culture broth (29 mg/g
dry mycelia). This value accounted for 13.5% of the total fatty acids in the extracted lipids. Other major fatty acids in
the lipids were palmitic acid (6.0%, by weight), stearic acid (5.3), oleic acid (6.2), linoleic acid (3.0), γ-linolenic acid
(3.5) and arachidonic acid (60.0).
On leave from Suntory Ltd. 相似文献
7.
Sakayu Shimizu Hiroshi Kawashima Kengo Akimoto Yoshifumi Shinmen Hideaki Yamada 《Journal of the American Oil Chemists' Society》1991,68(4):254-258
A soil isolate,Mortierella alpina 1S-4, was found to show high production of odd chain polyunsaturated fatty acids (PUFAs) among various arachidonic acid-producingMortierella strains tested. The fungus mainly accumulated 5,8,11,M-cis-nonadecatetraenoic acid. With 5%n-hepta-decane and 1% yeast extract as growth substrates, the amount of C19:4:4 acid accumulated reached 44.4 mg/g dry mycelia (0.68 mg/mL of culture broth). This value accounted for 11.2% of the total
fatty acids in the extracted lipids from mycelia, and odd chain fatty acids comprised over 95% of the total mycelial fatty
acids. The addition of sesamin, a specific inhibitor of A5 desaturation, caused an increase in C19:3 acid and an accompanying decrease in C19:4 acid. On the other hand, species ofMortierella that could not produce C-20 PUFAs accumulated C-17 acids, but no C-19 PUFAs, when grown with fatty substrates with an odd
chain skeleton. The odd chain PUFAs were distributed in both neutral and polar lipids. The biosynthetic route to C19:4 acid was presumed to mimic the n-6 route to arachidonic acid as follows: C17:0 → C17:1→ C17:2→ C17:3 → C19:3 → C19:4 acids.
On leave from Suntory Ltd. 相似文献
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