著者
新村 寿夫 鈴木 隆雄 佐橋 佳一
出版者
公益社団法人 日本ビタミン学会
雑誌
ビタミン (ISSN:0006386X)
巻号頁・発行日
vol.26, no.1, pp.38-42, 1962

Biosynthesis of biotin from DL-desthiobiotin by washed cells of Saccharomyces cerevisiae was investigated. It was found to be the best condition for biosynthesis of biotin that the cells, which were cultured in a liquid medium containing a suboptimal amount (20 mμg per 100ml) of DL-desthiobiotin during one to three days, were incubated in the reaction mixture containing DL-desthiobiotin (2×10^<-7>M) and glucose at 37℃ without shaking. The addition of several sulfur compounds did not increase the production of biotin. Therefore, sulfur source on biosynthesis of biotin by washed cells was supplied with the sulfur compounds present in the cell. The synthesized biotin was practically restricted intracellulary under this condition and 87 per cent of the biotin was present in a esterified form.
著者
山田 良平
出版者
公益社団法人 日本ビタミン学会
雑誌
ビタミン (ISSN:0006386X)
巻号頁・発行日
vol.62, no.3, pp.117-127, 1988-03-25 (Released:2018-03-16)

Administration of isoniazid to mice induced a remarkable inhibition of liver cytosolic aspartate aminotransferase. Experimental findings indicated that the inhibitor was not isoniazid itself but probably its metabolite. DL-Hydrazinosuccinate, a model compound of the metabolite, was synthesized since the metabolite was not successfully isolated. The compound was found to be even more inhibitory. The inhibition by the compound proceeded time-dependently and was not readily released. D- and L-Hydrazinosuccinate were synthesized, respectively, for further analyses of the inhibition mechanisms. D-Hydrazinosuccinate was found to behave as a slow-binding inhibitor via a single-step reaction mechanism and gave Ki of approx. 3 nM. L-Hydrazinosuccinate was a more powerful inhibitor with Ki of approx. 0.2 nM, and was found to be a slow, tight-binding inhibitor and interact with the enzyme through consecutive reversible steps. Administration of L-hydrazinosuccinate to mice produced in vivo a potent and long lasting inhibition of cytosolic aspartate aminotransferase in the liver and kidney in a relatively specific manner. The administration of this compound also caused a remarkable accumulation of citrulline in the liver and plasma, which was explained as a result of both specific and non-specific effects of the inhibitor.
著者
佐藤(三戸) 夏子 瀧本 秀美
出版者
公益社団法人 日本ビタミン学会
雑誌
ビタミン (ISSN:0006386X)
巻号頁・発行日
vol.82, no.1, pp.19-23, 2008-01-25 (Released:2017-10-10)
参考文献数
45

Folate is a water-soluble vitamin, which is one of vitamin B group, and is involved in DNA synthesis cycle and methylamine cycle. It is known that folate deficiency is associated with pernicious anemia. Folate is also an important nutrient for an embryo, because recent many studies reveal an association between maternal folate status and fetal neural tube defects (NTDs). In 2002, Japanese government recommended that all women planning a pregnancy should consume an additional 400μg/day of supplementary folate to reduce risk of NTDs, referring to scientific evidence and recommendations in the other countries. It is also reported that folate is an important nutrient for not only the prevention of NTDs but also health of mother and fetus. As the prevalence of NTDs was low in Japan compared with other countries in the past, folate status in Japanese has not been fully investigated. Folate has been recently added to the Dietary Reference Intake for Japanese and Standard Table of Food Composition in Japan since 2000.
著者
福井 浩二 高津 博勝 浦野 四郎
出版者
公益社団法人 日本ビタミン学会
雑誌
ビタミン (ISSN:0006386X)
巻号頁・発行日
vol.85, no.10, pp.531-537, 2011-10-25 (Released:2017-10-10)
参考文献数
19
被引用文献数
1

Reactive oxygen species (ROS) may attack several types of living tissues and induce neuronal apoptosis in the brain. In our previous study, we examined about the relationship between ROS-induced neuronal cell death and cognitive dysfunction during aging. In order to verify, an early signs of neuronal change by ROS prior to induction of cell death, we examined the neurite condition after treatment of neurons with low concentrations of hydrogen peroxide. Treatment of neurons with low concentrations of hydrogen peroxide induced neurite degeneration, and treatment with tocopherol or tocotrienols significantly inhibited these changes in neuronal cells. The neuroprotective effect of tocotrienols was stronger than that of tocopherol. Furthermore, treatment with tocotrienols prevented degeneration of a specific protein present in neurite by hydrogen peroxide. These results suggest that neurite degeneration may be one of the early events of hydrogen peroxide-induced neuronal degeneration, and that tocotrienols may protect neurite function from oxidative damage through their neuroprotective function.
著者
原 登久子 美濃 真
出版者
公益社団法人 日本ビタミン学会
雑誌
ビタミン (ISSN:0006386X)
巻号頁・発行日
vol.71, no.10, pp.475-479, 1997
参考文献数
27
被引用文献数
2

平成6年の国民栄養調査を基に、大阪府民のEとPUFA摂取量を詳しく調べ、日本人のE所要量の考察を行った。1)大阪府民のE摂取量はα-トコフェロールとして一人一日あたり8.3mgであった。2)大阪府民の一人一日あたりの脂肪、飽和脂肪酸、一価不飽和脂肪酸、多価不飽和脂肪酸はそれぞれ59.8g, 17.0g, 20.9g, 15.1gであった。3)E/PUFA比は0.55であったがPUFAすべてをリノール酸に換算した場合E/PUFA比は0.39となった。
著者
山本 格
出版者
公益社団法人 日本ビタミン学会
雑誌
ビタミン (ISSN:0006386X)
巻号頁・発行日
vol.77, no.7, pp.383-395, 2003-07-25 (Released:2017-12-26)
参考文献数
44
被引用文献数
1

In 1989, we have developed a novel vitamin C derivative, 2-O-α-D-glucopyranosyl-L-ascorbic acid (AA-2G), which is highly stable to heat and oxidative stress. This stable form of ascorbate, of which hydroxy moiety at the C-2 position is regiospecifically substituted with glucose, was enzymatically synthesizes with mammalian intestinal and rice seed α-glucosidase, and cyclodextrin glucanotans-ferase from Bachillus stearothermophylus. In 1999, we have also reported a series of 6-acylated forms of AA-2G, 6-Acyl-AA-2Gs, of which hydroxy moiety at the C-6 position of AA-2G is substituted with fatty acids having a different length of carbon chains. Exposure both of AA-2G and 6-Acyl-AA-2G to the mammalian biomembrance results in the formation of active vitamin C by α-glucosidase and/or esterase. AA-2G has been admitted as a medicinal additive for whitening and is widely used in domestic and foreign countries for years. Our of the various acylated derivatives, 6-O-dodecanoyl-2-O-α-D-glucopyranosyl-L-ascorbic acid is considered to be the most expected candidate in application for medicinal use, for examples, preservation solution for the grafts, whitening ingredient, food additives and medicines, because it is the most prominent one in terms of the stability, effectiveness and skin permeability. The two types of ascorbate derivatives are very useful vitamin C source, especially in the tissue culture experiments and contribute the finding of unknown physiological action, and to the clarification of the mode of action of ascorbate. It has been found that vitamin C stimulates the cytokine generation and enhances the cytokine-induced biological activity in immune and neurological responses, although ascorbate alone is without effect. These findings suggest that AA-2G and 6-Acyl-AA-2G not only may serve as useful agents for the medicinal and cosmetic use, but also contributes to shed some light on a new aspect of the biological activity of ascorbate.