Reactions of N-succinimidyl arylacetates (1) with aliphatic primary amines (2) giving the corresponding N- (arylacetyl) amines were studied kinetically in aqueous solution (7.0≤pH≤9.0) at 25°C. The N-arylacetylation of (2) by (1) was competitive with the decomposition of (1) and the rate could be expressed as V= (kd+k2 ) , where kd and k2 are the rate constants of decomposition and N-arylacetylation, respectively. The rate of N-arylacetylation was influenced by inductive and steric effects of the alkyl group in (2) and by the substituent in (1). Plots of log k2vs. pH (pH profile) showed a good linear relationship with a slope of unity. The rates of meta- and para-substituted (1) correlated with the Hammett σ value, and gave positive ρ values. The rate ratios, 10-3k2/kd, increased with pH and exceeded unity for straight chains and isobutyl amines at pH≥8.0. Based on the results presented above, the reaction mechanism is considered to possibly involve a nucleophilic attack of the free amino group in (2) on the ester carbonyl carbon in (1). Compound (1) was revealed to function as an N-arylacetylation reagent of amino compounds in aqueous solution.
Five groups of weanling male rats were maintained on diets containing 20% fish oils with different degrees of hardening supplemented with the minimal linoleate requirement as safflower oil for 28 days. The effects of these fats on liver weight and fatty acid profiles of tissue and fecal lipids were examined. The fats used were an unhardened oil (FO) mainly consisting of sardine oil and four kinds of hardened fats (HFO) obtained stepwise during the hardening process of FO. 1) A transit increase in relative liver weight was observed in both the HFO and the FO groups, and was proportional to the amounts of n-3 polyunsaturated fatty acids in dietary fats. 2) The results of fatty acid analysis of liver and heart lipids indicated the incorporation of n-6 and n-3 polyunsaturated fatty acids in tissue lipids to possibly occur competitively. 3) From analysis of fatty acid compositions of liver, heart and fecal lipids the preferential fecal dischargement of trans-fatty acids, particularly long chain trans-isomers was evident and resumption of the tissue levels of linoleic acid and n-3 polyunsaturated fatty acids was noted to occur easily. The present results agree essentially with those reported previously.
Discriminatory and qualitative evaluation of natural waxes was made by thermogravimetry (TG) under a stream of air. A simple method for detecting paraffin wax adulterated in other waxes was also devised by the same means. 1) The pattern of weight reduction on the TG curve differed according to the kind of natural wax. Weight reduction in waxes was initiated at 179°C and the lowest for Japan wax, and highest for carnauba wax at 252°C. The rate of weight reduction from the initial temperature to 300°C was highest for candelilla wax and bees wax of more than 20%. The rate of weight reduction from 300 to 350°C was highest for carnauba wax and bees wax, and the rate from 350450°C was higher for rice bran wax and Japan wax. 2) According to TG analysis of components fractionated from the waxes by silica gel column chromatography, each component showed characteristic pyrolysis behavior. However, little difference was observed in the behavior of the same components from different waxes. This indicates that the pattern of weight reduction on TG curve of natural wax is dependent on composition and component content. 3) The initial temperature of weight reduction on TG curve was closely correlated to the melting point for natural wax. 4) Paraffin waxes adulterated to natural wax could be detected by the initial temperature of weight reduction on the TG curve when present at more than 5% in those with lower melting point and 20% in those with higher melting point. Paraffin wax with lower melting point could be also detected by the rate of weight reduction from the initial temperature to 300°C.
The reaction of 1-phenylethanol with alcohols, thiols and carboxylic acids in the presence of the montmorillonite K-10 was found to give the corresponding ethers, sulfides and esters. And diphenylmethanol and triphenylmethanol were also allowed to react with some nucleophiles using K-10 clay to give the substituted products.
In the system of 8wt% CaCl2 aq./C12H25OCH2CH2SO4Ca0.5/i-C8H17OCH2CH (OH) CH2OH/decane with only 3wt% of total amphiphiles, it was possible to obtain only one phase region of microemulsion whose solvents swelled by 97wt% (water+oil). The composition of water and oil varied over the entire range with slight changes in the amphiphile ratio from 0.380.42. The self-diffusion measurements indicated the microemulsion microstructure to change from O/W, a hydrophilic conditions to W/O, a lipophilic condition via bi (tri) continuous with change hydrophile-lipophile balance of the amphiphiles. From a comparison of these results with change in temperature in a nonionic surfactant system, it is evident that the change in the ratio of hydrophilic amphiphile and lipophilic amphiphile, from 0.38 to 0.42 in the present study has the same effect as that in HLB by making the temperature 30°C in the nonionic surfactant system.
The antioxidative and antimicrobial activities of sesamol (5-hydroxy-1, 3-dioxaindan) are considered due to the phenolic hydroxyl group in its molecule. 2, 2-Dialkyl-1, 3-dioxaindans were found to have slight antioxidative activity, although they possess no phenolic hydroxyl group. Alkyl groups at the 2-position were found responsible to some extent for the antioxidative activity of 2, 2-dialkyl-1, 3-dioxaindans. In the present study, the synthesis of various 2-alkyl-2-methyl-1, 3-dioxaindans was conducted and their antioxidative activity toward lard antioxidation determined. The antioxidative activity of 2-alkyl-2-methyl-1, 3-dioxaindans was noted to bear some relationship to alkyl groups at the 2-position.
Preparation of O/W/O-type multiple emulsions was examined by applying conditions previously used for obtaining W/O/W emulsions. Main aim of the study is to confirm whether two different types of multiple emulsions would be formed around the phase inversion region of a ternary system of oil, water and emulsifier. The used samples were comprised of different combinations of components, such as liquid paraffin systems emulsified with Span 80 and Tween 80 and an olive oil system stabilized by TGCR (tetraglyceryl condensed ricinolate). The results for the liquid paraffin system indicated about twice or less Span 80 than Tween 80 to be necessary for obtaining 70% or higher yields of O/W/O emulsions, in contrast to W/O/W emulsions. O/W/O-type dispersion in the olive oil system occurred prior to phase inversion of the W/O emulsion, leading to formation of W/O/W emulsions. The two different types of multiple emulsions both containing the same components, thus to actually be formed about the phase inversion region of the ternary system.
The fatty acid compositions and physical characteristics of recently produced bakery margarines were determined for each of 5 brands of margarines for bread, cake, pie or pastry, chou puff and whipped cream. Melting points were measured by 4 methods using 2 types of automatic apparatus, and solid fat content (SFC), hardness index by cone-penetration, oil-off and creaming values were also determined. An attempt was made to determine if these parameters were correlated to fatty acid compositions. 1) Long chain fatty acids having 20 or more carbons were detected in relatively high proportions from 14 brands, indicating the blending of hardened marine oil, but shorter chain acids with less than 12 carbons were not found in any of the brands examined, indicating no blending of laurin oils. Trans-isomers of unsaturated fatty acids, mainly t-18 : 1, were detected in all brands, at levels averaging 7.2% for t-18 : 1, 3.1% for t-20 : 1 and 1.6% for t-22 : 1, all below the levels expected. Fatty acid compositions indicated no characteristic features. 2) From measurements of the above physical parameters, the margarines for pie or pastry were hardest, followed by those for chou puff, while those for whipped cream were the softest. Softer types tended to shed their oil-off more easily. However, the type for pie or pastry showed somewhat less SFC than that for chou puff at a temperature lower than 30°C. 3) The hardness index was correlated with SFC for bakery margarines but neither of these values was correlated with the oil-off value. Also, SFC and the hardness index at 20°C were not correlated to the total % of unsaturated fatty acids except trans-isomers, and not correlated to a total % of polyunsaturated fatty acids (18 : 2+18 : 3). although these correlations have been considered to exist in the case of household margarines [J. Jpn. Oil Chem. Soc., Yukagaku, 36, 594 (1987)].
The fatty acid composition of body oil extracted from lamprey, Entosphenus japonicas Martens, in spring (Apr.May) and autumn (Aug.Dec.) was determined by GLC and GC-MS. 1) The major (>10%) n-3 fatty acids of lamprey body oil were C20 : 5 and C22 : 6. 2) The ratio of fatty acids, C14 : 0/C16 : 0/C16 : 1/C18 : 1/C20 : 5/C22 : 6 in lamprey body oil was approximately 1 : 2 : 2 : 3.8 : 2 : 2.