Two major methods currently used in Japan for determining lipase hydrolytic activity, i.e., surfactant [poly (vinly alcohol), PVA] addition and surfactant non-addition, were compared under experimental conditions made the same as much as possible. PVA inhibited the olive oil hydrolytic activity of all three lipases tested (lipases produced by Candida cylindracea, Pseudomonas fluorescens and Rhizopus japonicus). The degree of inhibition depended on the lipase. There was some indication as to which olive oil would be suitable as a substrate and the application limit of each method. Advantages and disadvantages of both method are comparatively discussed.

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Tertiary amines with three different substituents were prepared. N, N Disubstituted ethanolamines readily and quantitatively reacted with alkyl halides to give quaternary 2-hydroxyl-ammonium halides. The quaternary salts, when treated with a small excess of potassium hydroxide at 120°C, afforded tertiary amines in high yields, accompanied by the evolution of ethylene oxide. N, N-Dimethylalkylamines were prepared quantitatively in a one-pot reaction procedure from N, N-dimethyl-ethanolamine and alkyl halides.

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A study was made of how cultural conditions [incubation temperature, incubation pH and quantity of nitrogen source (C/N ratio)] influence the amounts of lipids produced from glucose in the bath culture fermentation of Mortierella isabellina. Cell growth and lipid content were found to be influenced by incubation pH and the quantity of available nitrogen. In incubation of low pH, lipid accumulation increased, but the rate of cell growth decreased. On using ammonium sulfate as the source of nitrogen at a C/N ratio of 62.9 the maximum accumulation of lipids in the mycelium was 5.49 g/L. Lipid accumulation of M. isabellina was increased from 19.0% to 66.6 % on increasing the C/N ratio from 7.9 to 62.9.

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A washing method was developed to import beneficial mechanical effects to sheets of soiled cotton fabric, fabric deformation clash of the fabric against wire gauze and penetration of a liquid flow through the fabric. This method consists in pulsating flows of through the fabric placed between two wire gauzes set in a cylinder.
Detergency was shown by this method to be about two times that possible by a commercial washing machine. The detersive efficiency was correlated to the product, (clash pressure) (frequency). Only half the amount of detergent was necessary to obtain the same degree of detergency as that by a commercial washing machine. Analysis of the experimental data clarified the effects fabric deformation fabric, its clash against the wire gauze and penetration of a liquid flow through the fabric on total detergency.

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The rate of capillary wetting in fibrous assemblies was measured using newly developed apparatus. The change in electric conductivity with time was measured using a plug of fiber, fabric, or filter paper in a cylinderical Teflon cell 10 mm in inner radius and 3 mm or 7 mm in height. The electrodes were platinum disks 16 mm in diameter with 37 holes each with a radius of 0.5 mm. They were placed at the top and bottom of the plug. The head of the wetting liquid was adjusted to the bottom level of the plug and the liquid rose by capillarity. The traveling time in the shortest capillary in the fibrous assembly, t₀, is detected as the yield value in the electric conductivity versus time curves, and the initial slope of the curves, S, were used as parameters of the wetting rate. The increase in t₀ and decrease in S was indication of decrease in the capillary wetting rate for the plug. Measurement of capillary wetting rate by this apparatus was successfully carried out using plugs of cellulose filter paper, polyester fabric, and nylon fiber.

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The solution properties of mixed amphoteric-nonionic surfactant systems in aqueous solutions were studied in terms of Krafft points and surface tension. The systems examined were N^α, N^α-dimethyl-N^ε-acyllysine (DMLL) -alkyl poly (oxyethylene) ethers (C_mPOE₂₀; m=12, 14, 16 and 18). The Krafft point of DMLL decreased with increasing molar ratio of C_mPOE₂₀, becoming less than 0°C at a certain molar ratio. The Krafft point of DMLL mixed with a nonionic surfactant possessing a long alkyl chain was lower than that mixed with nonionic surfactant with a short alkyl chain. The surface tension of each mixed surfactant solution decreased with increasing concentration of DMLL. The cmc values of the mixed systems decreased with increasing to alkyl chain length of C_mPOE₂₀. These properties attributed to increased molecular interaction between DMLL and C_mPOE₂₀ in mixed micelles with increasing alkyl chain length in nonionic surfactants.

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The isomerization reactions of styrene oxide (1) and other reactions of (1) with acetone catalyzed by mineral acids (HNO₃, H₂SO₄, H₃PO₄, HCl) -treated activated carbon were investigated.
The following results were obtained : Phenylacetaldehyde was quantitatively obtained (yield 94%) by the isomerization of (1) catalyzed by 2 N HNO₃-treated activated carbon in ethyl acetate at 75°C.
2, 2-Dimethyl-4-phenyl-1, 3-dioxolane was synthesize in high yield (81%) by a simple reaction (1) with acetone catalyzed by 2 N H₂SO₄-treated activated carbon at 55°C.

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The reactions of amino groups in amino acids and proteins with sodium 2, 4, 6-trinitrobenzenesulfonate (TNBS·Na) in the presence of sodium sulfite (Na₂SO₃) were studied at pH 10.1. Determination of the amino groups was performed by following the absorbance A (420 nm) of the Meisenheimer complex. A good linear relationship between A and the concentrations of amino compounds was observed. The reactions in a cuvette showed good agreement with those in the dark. Based on these observations, a modified method for determining amino groups by TNBS·Na in the presence of Na₂SO₃ is proposed, and several comments are described.

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