Recent studies on mixed surfactant systems were systematically overviewed, paying special attention to synergism observed in micellization as well as adsorbed film formation upon mixing of a few nonionic surfactants with a variety of surfactants (such as anionics including bile salts and a hybrid type surfactant, cationics including a Gemini type surfactant, different types of nonionics and a zwitterionic surfactant used as a membrane solubilizer) in addition to various combinations of anionics. Through the text, it was shown for each given binary mixed system composed of surfactants 1 and 2 how to estimate not only the composition of mixed micelles (Y₂) equilibrated with singly dispersed surfactant species in bulk solution phase, where the mole fraction of 2 in the surfactant mixture is denoted as X₂, but also the composition of adsorbed film phase (Z₂). Almost all combinations were discussed in terms of the respective interaction parameters, ω_R and ω_A, in mixed micelles (3-D phase) and in mixed adsorbed film (2-D phase), respectively, surface excess concentration (Γ), partial molecular area (PMA), minimum surface Gibbs energy (G^(S)_min), and such defined measures as pC₂₀, CMC/C₂₀ etc. for evaluation of synergism.

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2,3-Dihydro-1H-imidazo[1,2-a]pyridine-4-ylium derivatives with UV absorption at 350 nm were formed by reaction of one molar of any sugar except 2-deoxysugars with two molar of phosphatidylethanolamines involving a new pseudo Maillard rearrangement reaction. To elucidate the reaction mechanism, 2-aminoethyl dihydrogenphosphate, which had a partially similar structural moiety to PE, was reacted with D-galactose. Though the UV absorption at 365 nm was not observed and the four pyridinium derivatives were also not formed in the reactant solution, the UV absorption at 286 nm and browning of the reactant solution were observed. From this reactant solution, two compounds with λmax at 283 nm and 297 nm were isolated and former was determined as 5-(hydroxymethyl)furfural (HMF) and later did as phosphoric acid mono{2-[2-formyl-5-(hydroxymethyl)-1H-pyrrol-1-yl]ethyl}ester (PMPEE), which is a new compound, respectively. Because reaction of PMPEE with PE leads to form the pyridinium derivatives, we concluded that a compound like PMPEE was one of intermediates in this new reaction.

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In previous studies, statistical method using distribution of detergent power and that of resistance of soil against washing was applied to analyze detergency of oily soil and solid particle soil. In this paper, this method was applied to an analysis of detergency of mixed soil. Artificially soiled cloth prepared by aqueous dispersion method was used as a mixed soil sample. Four-time consecutive washing tests were conducted under the same washing condition in Terg-O-Tometer using two kinds of detergent solution and distilled water. Change of removal efficiencies due to repetitive washing was used to determine the two distributions. Result shows that detergent power can be expressed as cumulative distribution function. In washing simulation using the cumulative distribution functions, the predicted removal efficiencies corresponded with experimental values. Moreover, the effect of soil aging on distribution of soil resistance against washing was found to move the distribution curve toward high resistance. These results show that the method using two statistical distributions can be applied to the detergency of mixed soil.

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The synthesis and physiological activity of thiophenes and furans with methoxyacetophenone derivatives were examined. 3-Methoxyacetophenone (1) and 4-methoxyacetophenone (2) were converted, respectively, to the oximes (3) and (4) by oximation with hydroxylamine hydrochloride, and to the primary amines (5) and (6) by reduction with LiAlH₄. The primary amine derivatives were further converted into the thiophene and furan compounds (5a)∼(5h) and (6a)∼(6h), respectively. Bioassay of these compounds (5a)∼(5h) and (6a)∼(6h) on the germination of lettuce(Lactuca satiba) seeds showed that compound (5b) exhibits growthpromoting activity.

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It has been reported that saliva may play an important role in the prevention and development of enamel caries and that both lipids and protein contents in saliva may be relevant to this role. This study examined the lipid and protein levels in saliva from individuals differing in caries experience. Female subjects (20 to 21 years old) were used divided equally into two groups, caries-susceptible group (CSG) and caries-resistant group (CRG). Stimulated parotid saliva and stimulated whole saliva were collected from the subjects. After centrifugation, each saliva sample was analyzed for the concentrations of lipids and proteins and for the compositions of lipids and fatty acids. The lipid and protein contents in parotid saliva increased in proportion to increase of the flow rate. The lipid content was slightly correlated with the protein one (r = 0.33). Total lipid and protein concentrations were higher in the samples from CSG than those from CRG. The lipid composition was similar in the samples from the two groups; more than half in total lipids was neutral lipids, followed by glycolipids and phospholipids. Neutral lipids and free fatty acid and triacylglyceride concentrations were significantly higher in the samples from CSG than those from CRG (p<0.01 for each). Also stearic, linoleic and docosahexaenoic acids were significantly higher in the former group than the latter one (p<0.05 and p<0.01). In summary, the lipid concentrations in parotid saliva from caries susceptible subjects were higher than those from caries resistant ones, and the difference in fatty acid composition was detected between them. The variations in the lipid levels and fatty acid composition may be associated with those in caries development.

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A basidiomycetous yeast, Pseudozyma graminicola CBS 10092, was found to accumulate a large amount of glycolipids in the cultured medium when grown on soybean oil as the sole carbon source. Based on thin layer chromatography, the extracellular glycolipids gave spots corresponding to those of mannosylerythritol lipids (MELs), which are highly functional and promising biosurfactants. From the structural characterization by ¹H and ¹³C NMR, the main product was identified as 4-O-[(4′-mono-O-acetyl-2′, 3′-di-O-alka(e)noyl)-β-D-mannopyranosyl]-D-erythritol, which is a highly hydrophilic derivative of MELs known as MEL-C. According to high-performance liquid chromatography analysis, the main product, MEL-C, comprised approximately 85% of all the MELs, and the total amount reached approximately 10 g/L for 7 days. The fatty acids of the present MEL-C consisted of mainly C₆, C₈ and C₁₄ acids, considerably different from those of MEL-C produced by other Pseudozyma strains such as P. antarctica and P. shanxiensis. The observed critical micelle concentration (CMC) and the surface-tension at CMC of the MEL-C were 4.0 × 10^-6 M and 24.2 mN/m, respectively, while those of MEL-A, the most intensively studied MEL, were 2.7 × 10^-6 M and 28.4 mN/m, respectively. This implied that the MEL-C has higher hydrophilicity than conventional MELs hitherto reported. In addition, on a water-penetration scan, the MEL-C efficiently formed the lamella phase (L_α) at a wide range of concentrations, indicating its excellent self-assembling properties. From these results, the newly identified MELs produced by P. graminicola are likely to have great potential for use in oil-in-water type emulsifiers and/or washing detergents, and would thus facilitate a broad range of applications for the promising yeast biosurfactants.

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The effects of ferulic acid (FA) and γ-oryzanol (OZ) supplementation on cultured red sea bream were examined. Commercial brown fish meal diets supplemented with FA (0.01-0.5%) or OZ (0.05-0.5%) were given to zero-year, cultured red sea bream for 98 days. After the experiment, the brightness of the integument color (“L” value) of FA- and OZ-administrated fish was higher than that of control fish. Furthermore, 2-Thiobarbituric acid reactive substances (TBARS) in the liver of FA- and OZ-administrated fish was lower than in control fish. These results indicate that FA and OZ suppressed not only dark-color pigmentation but also oxidative stress in cultured red sea bream.

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