- 著者
- Ippei SUZUKI Yasuhito KUMAI Machiko KITAGAWA Yuka KISHIMOTO Keizo UMEGAKI Tsuyoshi CHIBA Jun TAKEBAYASHI
- 出版者
- The Japan Society for Analytical Chemistry
- 雑誌
- Analytical Sciences (ISSN:09106340)
- 巻号頁・発行日
- vol.35, no.11, pp.1269-1274, 2019-11-10 (Released:2019-11-10)
- 参考文献数
- 11
- 被引用文献数
- 3
In HPLC analyses of soluble dietary fiber, desalting processes using open, mixed-bed ion-exchange columns are time-consuming and labor-intensive. We developed and validated a simple desalting method using tandem cation/anion exchange SPE cartridges. We found that combining Bond Elut Jr SCX (upstream) and Bond Elut PSA (downstream) cartridges provided adequate desalting of test solutions. The developed method was then validated in an inter-laboratory study. Five test samples were prepared by mixing food matrixes with purified soluble dietary fiber and treated to generate solutions to test the desalting process. These solutions were then analyzed by eight different laboratories. The results demonstrated that the developed method is simple and reliable for desalting samples containing 140 to 945 mg/100 mL of soluble dietary fiber in preparation for HPLC analysis of soluble dietary fiber.
- 著者
- Yasuyuki Sadzuka Chieko Inoue Saho Hirooka Tomomi Sugiyama Keizo Umegaki Takashi Sonobe
- 出版者
- The Pharmaceutical Society of Japan
- 雑誌
- Biological and Pharmaceutical Bulletin (ISSN:09186158)
- 巻号頁・発行日
- vol.28, no.9, pp.1702-1706, 2005 (Released:2005-09-01)
- 参考文献数
- 42
- 被引用文献数
- 19 19
We previously showed that theanine, is a major amino acid in green tea, enhanced doxorubicin (DOX) induced antitumor activity. Besides, theanine induced the elevation of glutathione (GSH) level attributable to the increase of glutamate in the liver of mice, namely theanine would reduce the adverse reaction of DOX. Consequently, theanine was thought to be effective against the tissue changes with GSH level reduction. On the other hand, it is suggested excessive uptake of alcohol causes a production of free radicals, a decrease of GSH level, and an increase in the amount of lipid peroxide (LPO) in liver, and shifting to an alcoholic liver injury. Then, aiming at the prevention and medical treatment of a hepatic toxicity by the food components with little toxicity, we have studied the effect of theanine (i.p.) on ethanol metabolism and hepatic toxicity using ethanol (p.o.) single-administered mice. On the 1st hour after ethanol administration, the ethanol concentrations in blood of the theanine combined groups decreased compared with the ethanol-alone group. The alcohol dehydrogenase and aldehyde dehydrogenase activities in the liver increased by combined theanine. Since the elevation of cytochrome P450 (CYP) 2E1 activity was controlled in the theanine-combined groups, it was considered that these disorders attributable to CYP2E1 in ethanol long-term uptake might be avoidable by theanine. Although LPO increased in 3 h after by single-administration of ethanol, the increase was controlled by theanine-administration and was improved until the normal level. In conclusion, it was indicated that theanine was effective against alcoholic liver injury.
- 著者
- Yuko Taki Yuko Yamazaki Fumio Shimura Shizuo Yamada Keizo Umegaki
- 出版者
- The Japanese Pharmacological Society
- 雑誌
- Journal of Pharmacological Sciences (ISSN:13478613)
- 巻号頁・発行日
- vol.109, no.3, pp.459-462, 2009 (Released:2009-03-20)
- 参考文献数
- 14
- 被引用文献数
- 13 20
A single dose by gavage of bilobalide (30 mg/kg) was found to produce a time-dependent induction of hepatic cytochrome P450 (CYP) enzyme activity and protein expression in rats. An RT-PCR study further showed that mRNA expression of CYP2B was maximal at 6 h. Plasma and liver bilobalide concentration in rats following administration of Ginkgo biloba extract equivalent to bilobalide of approximately 40 mg/kg showed a similar response to that exhibited by mRNA expression. These findings suggest that bilobalide markedly induced hepatic CYPs, but the induction could be mitigated due to rapid elimination from the liver.