This paper deals systematic investigation of the operational conditions for the rapid gas-liquid chromatography (GLC) of fatty acids, which utilizes in situ methylation of these acids by the pyrolysis of their tetramethyl ammonium salts (TMA salts) in the injection port of gas chromatograph. The optimum condition for practical rapid GLC was obtained from the investigation of the following parameters : (1) Kind of solvents used and their water content for obtaining complete dissolution of TMA salts. (2) Excess of tetramethyl ammonium hydroxide, drying time of TMA salt solution, and temperature of injection port for obtaining the complete methylation of fatty acids. (3) Applicability of this method for polyunsaturated fatty acids by modifying the pH of TMA salt solution.
As a part of studies on a method to prevent low-temperature deterioration of hardened coconut oil series, examinations were made on the addition of various surfactants as a means of preventing such phenomenon and it was found that these agents were classified into kinds, i.e., those that are really effective, those that have no effect and those that rather promote deterioration. 1) Addition of 0.52% of monostearin, monopalmitin or monolaurin, irrespective of the kind of glyceride and the amount added, showed increase in A.V. in the same degree as well the control samples of without addition, indicating that they have practically no effect of preventing deterioration. Uneven surface of the crystals was almost the same as that of the control samples. 2) Addition of 0.51% of sorbitan mono-fatty acid ester, polyoxyethylene sorbitan mono-fatty acid ester or lecithin indicated no increase of A.V. even when allowed to stand at 15°C for 6 months. The crystal surface, though with some difference according to the agent used, was composed of fine crystals, some being almost amorphous and the surface was smooth. Consequently, addition of a small amount of this kind of surfactants will be able to prevent deterioration completely. 3) Addition of sucrose fatty acid ester was almost in effective in preventing deterioration, although A.V. increase remained small in some. The crystal surface was indefinite but well grown and uneven. 4) Addition of malic acid monoglyceride ester resulted in a more marked increase of A.V. than the control sample. A large single crystal was formed on the surface which was highly uneven, showing that this agent rather promoted deterioration.
Mixtures of glycerides prepared by glycerolysis or direct esterification were fractionated in homogeneous phase by urea adduct method. Urea was added in each fractional stage. The weight of urea and solvent to be added, the solubility of urea in solvents and a forming tendency of urea adducts were examined. The experimental results were summarized as follows : 1) It is better for monolaurin and dilaurin to dissolve in methanol and also for trilaurin in methanol-benzene. 2) The ratios of urea and the solvent, 5 : 50 and 5 : 100 by weight, were the best for monolaurin and dilaurin respectively when 5g of the sample was used. 3) In case urea was added to the sample dissolved in methanol-benzene, a great deal of trilaurin could not form urea adduct, but crystallized more rapidly than 1, 3-dilaurin adduct. 4) In the above experimental conditions, pure 1-monolaurin, 1, 3-dilaurin and trilaurin were isolated. 5) On the tendency which glycerides are fractionated, the following results were obtained. Trilaurin>1.3-dilaurin >1.2-dilaurin>1-monolaurin> 2-monolaurin.
Thermally oxidized oils (TO) prepared by heating linseed and soybean oils at 275°C for 12 hours with air bubbling were directly fractionated by silicid acid column chromatography without derivatizing into their esters. By successive elution with 15%, 60% isopropyl ether in hexane and diethyl ether, the TO was separable into three fractions : the apolar fraction (fr. I) consisting of monomer of glycerides, slightly polar fraction (fr.II), and polar fraction (fr.III) comprising di- and polymer of glycerides. Subsequent feeding experiments by using mice revealed that the fraction III contained the toxic components, while the fraction I showed little difference from fresh oil in the nutritive value and fraction II is entirely non-toxic.
In order to make clear the mechanism of solubilization of water in nonaqueous solutions of dodecylammonium carboxylates, the vapor pressure of water solubilized by dodecylammonium propionate, butyrate, valerate, and caproate and the temperature dependence of the vapor pressure were measured, especially noting the initial stage of solubilization. The heat of solubilization (ΔHs) calculated from the measurement of the temperature dependence showed smaller values than the heat of condensation of water (ΔHw) in the initial stage of solubilization. ΔHs increased and exceeded ΔHw with addition of water. The solvent dependence of the ΔHs by dodecylammonium butyrate was observed in the initial stage of solubilization. The change of ΔHs with the amount of added water was explained with reference to the results of the NMR measurement of the carbon tetrachloride solution and water-solubilizing solution of dodecylammonium butyrate reported by Yan etal.
The soil removal efficiencies have been studied from the view of hydrophilic or oleophilic nature of surfactants, soil, and fabrics. In the case of washing by the detergent that is mainly formulated with LAS, the detergency depends on water hardness. The water hardness dependencies on the detergency for the hydrophilic fabrics such as cotton and nylon are comparatively small, but are great for the oleophilic fabrics such as wool, and consequently the maximum detergency is observed at a some water hardness. The water hardnesses corresponding to the maximum detergency depend on the polarity of soils adhered on fabric and increase with the increase of the polarity of soil. In the case of washing by the detergents that are mainly formulated with non-ionic surfactants, the dependency of detergency on the HLB of the surfactants is little for the hydrophilic fabrics such as cotton, but is great for the oleophilic fabrics such as wool.
The lipid of Hiratake (Pleurotus ostreatus Quel) was investigated on its general properties, the fatty acid compositions and the charactristics of unsaponifiable matter, comparing with those of Ventricosa and Akahatsu studied by author. The mashroom was dried and extracted with ether. The mixed fatty acid was esterified to methyl ester with methanol and p-toluen sulfonic acid. The fatty acid compositions determined by GLC were as follows, C14 : 0 1.1, C16 : 0 23.0, C16 : 1 10.4, C18 : 0 2.1, C18 : 1 36.2, C18 : 2 27.2 (%). The unsaponifiable matter was a light yellow soft solid. The sterol percentage in unsaponifiable matter was 20.7% and Δ5, 7-sterol 18.8%. The sterol was treated with TMSE and sterol compositions were determined by GLC. The main sterol was considered as ergosterol (70.0%).
Carboxylic acid type ion exchange resins, Amberlite IRC-84 show little damage of the beads in the conversion to the peracid type resins with hydrogen peroxide-sulfonic acid reagent. Soaking of the beads in the alkali solution gives splittings on the surface of the beads even at room temperature, which causes severe damage of the beads afterwards. The particle size of the beads did not show significant influence on the rate in the epoxidation of α-olefin.