Docosahexaenoic acid (DHA) was isolated from cellular membranes at the sn-2 position of phospholipids (PLs). Using conformation modeling computer software, data were obtained indicating DHA in PLs to possibly be tightly and regularly packed in the acyl chain array in cellular membranes under certain conditions. PLs containing DHA had stereospecific conformations, which may possibly be the reason for the important physiological functions of this lipid. PLs containing DHA express difference induction and inhibited 5-lipoxygenase and lecithin-cholesterol acyltransferase activity. They were found essential to integrated brain functions such as learning ability and the inducement of paradoxical sleep.
Examination was made of the synergistic antioxidant effects of various components in coffee beans with tocopherols (Toc) on cookies by storage tests at 40°C for 12 months. The components were 2-carboxy-3, 4, 5-trihydroxycyclohexyl 3, 4-dihydroxycinnamate (chlorogenic acid, Chl), 3', 4'-dihydroxycinnamic acid (caffeic acid, Caf), a powder of roasted coffee beans (CP) and its extract (EE) obtained by ethanol treatment. A mixed tocopherol-concentrate (m-Toc) served as the antioxidant. The components were added to the cookies at 100 ppm for m-Toc, 100 and 200 ppm for Chl and Caf, 2 % for EE and 10 % for CP. Each cookie sample was periodically analyzed for peroxide value (POV) in the lipid fraction and residual Toc during storage. (1) In cookies without m-Toc, Chl and Caf slightly suppressed increase in POV, while EE and CP did so markedly. The synergistic effect of Caf in cookies with m-Toc was clearly evident but could be hardly detected in EE or CP, the antioxidant effect of EE or CP being much greater than that of m-Toc in cookies containing no antioxidative substances. (2) Caf, EE and CP, prevented the decomposition of Toc in cookies during storage, but Chl had such effect only weakly. (3) The sensory evaluation indicated Caf, EE and CP to delay the onset of rancid odor in cookies during storage.
Examination was made of the acylation reactions of Δ2-carene (1) and Δ3-carene (2) with acid anhydrides (acetic anhydride and propionic anhydride) in the presence of synthetic zeolites. The following results were obtained : In acetic anhydride and propionic anhydride with Y Type zeolites, the acylation of (1) gave 2-acetyl-3-carene (3) and 2-propionyl-3-carene (4) respectivery. In Y type Zeolites, 4-acetyl-2-carene (5) and 4-propionyl-2-carene (6) were obtained from (2) as the main products, respectively.
A new method was developed for preparing liposomes using an instananeous vacuum-dried lipid mixture. White lipid powder for preparing liposomes was easily obtained by spraying an organic solution of lipids into a vacuum at a temperature exceeding the boiling point of the organic solvent. The lipid mixture thus obtained could be quite easily hydrated and converted to liposomes possessing excellent trapping efficiency and trapped volume. The liposomes thus obtained was superior to that prepared by the freeze-dry or spray-dry method. The present method showed thus be readily applicable to industrial-scale production of liposomes.