The adsorption of water onto Fe2O3 and Al2O2 was investigated after mixing Fe2O3 powder and Al2O3 powder in the safflower oil with the water. The amount of adsorbed water was directly proportional to that of the Fe2O3 and increased exponentially with the amount of Al2O3 in the oil. The selective adsorption of structural water, unsymmetrically hydrogen bonded water and free water onto Fe2O3 and Al2O3 in this oil was measured by Near Infrared Spectrometry. Unsymmetrically hydrogen bonded water was adsorbed preferentially onto Fe2O3 and structural water with difficulty. Structural water easily adsorbed onto Al2O3 but free water did so with difficulty. The adsorption of structural, unsymmetrically hydrogen bonded and free water onto Fe2O3 was more selective than that onto Al2O3.
The main oxidized products of methyl linolenate such as a polymer, methyl linolenate monohydroperoxides (MLnHPO), and degraded products considerably effected the activation of trypsinogen. The polymer inhibited the activation of trypsinogen more than MLnHPO, whereas, the degraded products accelarated the activation. The inhibitory action of the polymer depended on the production of insoluble trypsinogen during the reaction of trypsinogen with the polymer. This substance contained a trypsinogen monomer but not trypsinogen polymerized by the intermolecular cross-linking of trypsinogen. 1.7 to 3.9 mol of the polymer were found to be bound covalently to 1 mol of trypsinogen as a complex in the insoluble substance.
In this paper, an attempt is made to solve the overlap problem of PUFA concentrated fish oil methyl ester peaks using a DEGS packed column. The components of the peaks were examined by GC-MS (reconstracted ion chromatogram and QM+ of a methyl silicone capillary column GC-MS) and a Carbowax 20 M capillary column GC. A comparison was made of the % area of concentrated PUFA-fish oil methyl ester, as determined by the DEGS packed column and Carbowax 20 M capillary column. Hexadecatetraenoic acid (C16 : 4) was found in the linoleic acid (C18 : 2) peak, and henicosapentaenoic acid (C21 : 5) in the peak found between those for icosapentaenoic acid (C20 : 5) and docosapentaenoic acid (C22 : 5). The peak of hexadecatetraenoic acid shifted according to the polarity change in the liquid phases in the DEGS packed column.
4-Oxoaldehydes, which are important intermediates for the syntheses of terpenoids and jasmonoids, are prepared from the reaction of nitroalkane with acrolein catalyzed by tertiary-phosphine as tributylphosphine, tricyclohexylphosphine or triphenylphosphine, followed by Nef reaction of the resulting 4-nitro aldehyde ethylene acetals. The Michael reaction of nitroethane (1 a) with acrolein was carried out using a variety of tertiary-phosphines as catalysts in benzene at room temperature. Acetalization in situ gave 1, 1-ethylenedioxy-4-nitropentane (2a) in 68% yields. In the reaction of nitroalkane (1 b) (1g) with acrolein, 4-nitro ethylene acetals (2b) (2g) were obtained in 62-70% yields. 4-Nitroethylene acetals (2e), (2f) were subjected to an electrochemical oxidative Nef reaction to give 4-oxoaldehydes (4e), (4f). These compounds were converted respectively to 4-oxononanal and 2- hydroxy-5-pentyltetrahydrofuran, the latter being an essential oil found in watermelon. Dihydro- and cis-methyl jasmonate (7) were prepared from 4-oxoaldehydes (4).
The antioxidative activity of α-and γ-tocotrienols in methyl linoleate was tested by weighing method at 60°C and was compared with that of α- and γ-tocopherols. Tocotrienols showed slightly superior or equal antioxidative activity to the corresponding tocopherols. To confirm the activity of the isopentenoid side chains of tocopherols, α-tocotrienyl acetate and squalene were tested. Neither substance showed any particular antioxidative or prooxidative activity.
The synergistic antioxidant effects of tocopherol (Toc) and L-ascorbyl stearate or riboflavine tetrabutyrate on lard and palm oil were investigated by the oven and AOM tests. The antioxidant effects of these esters were also studied in the same manner. The addition of monoglyceride in the test on L-ascorbyl stearate was examined so as to make a comparison with the results of the test on L-ascorbic acid reported previously [Yukagaku, 33, 361 (1984)]. 1) On lard, L-ascorbyl stearate showed little antioxidant effect, but improved slightly the antioxidant effect of Toc. 2) On palm oil, L-ascorbyl stearate had a stronger antioxidant effect than L-ascorbic acid. In particular, the period to attain POV 100 tended to increase with ester concentration. However, no synergistic effects with Toc were found. 3) The addition of monoglyceride improved the antioxidant effect of L-ascorbyl stearate and its synergistic effect with Toc on lard. These effects were almost comparable to those of L-ascorbic acid reported previously. 4) Riboflavine tetrabutyrate showed no antioxidant effects nor improved the antioxidant effect of Toc on fat, in vitro.
The solubilities of 1-hexanol, 1-octanol, 1-decanol, and 1-dodecanol in 1-propanol-water mixtures were measured. Solubility increased with rise in temperature and increasing concentration of 1-propanol. The slope of a plot of -1n (solubility) against 1/T became large as the 1-propanol concentration decreased. The dependence of solubility on the 1-propanol concentration increased in proportion to solute size.