- 著者
- Orie YOSHINARI Hideyo SATO Kiharu IGARASHI
- 出版者
- (社)日本農芸化学会
- 雑誌
- Bioscience, Biotechnology, and Biochemistry (ISSN:09168451)
- 巻号頁・発行日
- vol.73, no.5, pp.1033-1041, 2009-05-23 (Released:2009-05-23)
- 参考文献数
- 43
- 被引用文献数
- 89
The effects of a pumpkin paste concentrate and its components on oral glucose tolerance and serum lipid levels were determined in non-obese type 2 diabetic Goto-Kakizaki (GK) rats. In the oral glucose tolerance test, the pumpkin paste concentrate-fed group maintained a lower glucose level than the control group between 15 and 60 min. The compounds considered to be effective in improving glucose tolerance and contained in the methanol extract of the pumpkin in relatively abundant amounts were isolated and identified as trigonelline (TRG) and nicotinic acid (NA).Feeding a diet containing TRG and NA respectively improved and tended to improve glucose tolerance. The insulin level increased after 15 min in the TRG-fed GK rats and then gradually decreased over the next 120 min. In contrast, a gradual increase was seen in the insulin level over 120 min in the control GK rats not fed with TRG, suggesting that TRG could improve the insulin resistance. The serum and liver triglyceride (TG) levels in the TRG- and NA-fed GK rats were lower than those in the control GK rats. Lower activity of liver fatty acid synthase (FAS), and higher activity of liver carnitine palmitoyl transferase (CPT) and glucokinase (GLK) in the TRG- and NA-fed GK rats than in the control GK rats were observed. This suggests that the regulation of these enzyme activities by TRG and NA was closely related to the suppression of both TG accumulation and the progression of diabetes.
- 著者
- Tetuya SUGAWARA Kiharu IGARASHI
- 出版者
- Japanese Society for Food Science and Technology
- 雑誌
- Food Science and Technology Research (ISSN:13446606)
- 巻号頁・発行日
- vol.15, no.5, pp.499-506, 2009 (Released:2009-12-22)
- 参考文献数
- 14
- 被引用文献数
- 29 36
Major flavonoids contained in petals of edible chrysanthemum flowers (Chrysanthemum×morifolium Ramat. forma esculentum Makino, c.v Kotobuki) were identified, and their chemical compounds in relation to their radical scavenging activities and preventive effects against liver injury were compared. Based on retention times and UV spectra, three peaks on the HPLC chromatogram of the polyphenol fraction of edible chrysanthemum flowers confirmed the presence of luteolin 7-O-glucoside, apigenin 7-O-glucoside, and luteolin. Spectroscopic analysis determined the chemical structure of the three newly isolated compounds to be luteolin 7-O-(6''-O-malonyl)-glucoside, apigenin 7-O-(6''-O-malonyl)-glucoside, and acacetin 7-O-(6''-O-malonyl)-glucoside. Increases in plasma aspartate aminotransferase and alanine aminotransferase activities in mice (induced with liver injury by injection of carbon tetrachloride) were strongly suppressed by oral administration of luteolin and luteolin 7-O-(6''-O-malonyl)-glucoside, which have stronger radical scavenging activity than other compounds. Thus, it is suggested that compounds with chemical structures such as luteolin and luteoin 7-O-glucoside, which have maolonic acid on its glucosyl moiety, appear to readily available for mitigation of liver injury.