文章基本信息

标题：膵リパーゼ活性におよぼす胆汁酸塩の影響
本地全文：下载
作者：石原英子
期刊名称：Journal of Health Science
印刷版ISSN：1344-9702
电子版ISSN：1347-5207
出版年度：1975
卷号：21
期号：6
页码：348-355
DOI：10.1248/jhs1956.21.348
出版社：The Pharmaceutical Society of Japan
摘要：Effect of bile acid salts on lipolysis catalyzed by porcine pancreatic lipase was examined by kinetic treatment using pH-stat. 1) The shift of the wavelength of maximum absorption of a dye, Rhodamin 6G, was used to determine the critical micelle concentration of seven bile salts ; sodium cholate, taurocholate, deoxycholate, chenodeoxycholate, ursodeoxycholate, glycoursodeoxycholate and tauroursodeoxycholate. No data are available on the melting point, optical rotation, critical micelle concentration, and effect on lipase activity of the last two bile salts. 2) In this experiment, available surface area of oil droplets was estimated from turbidity, which was proportional to oil-water interface area. By using this method, reproducible data were obtained. This method may enable generalization of available surface area. 3) When tributyrin emulsion was used as a substrate, at the concentration higher than 1 mM, all of these bile salts inhibited lipase activity. In the presence of bile salts, the apparent Km increased, but Vm was not affected, except for chenodeoxycholate. Among the bile salts used, taurocholate was the most and cholate was the least inhibitory at 1 mM for lipase activity, judging from the values of Vm/Km. 4) When olive oil emulsified by polyvinyl alcohol was used as a substrate, effect of bile salts on lipase differed from the use of tributyrin. In the presence of bile salts, the apparent Km and Vm increased. In the presence of 1 mM taurocholate, Vm/Km increased 2-fold of that in the absence of bile salts. As a stabilizing emulsifier, arabic gum was not favorable for estimating the effect of bile salts.