The authors focus on tuna shavings as a natural resource which hither to has been unused, they contain a high concentration of phospholipids including docosahexaenoic acid (DHA-PL) and are a by-product of factory processed tuna. Supercritical carbon dioxide (SC-CO₂) although a suitable substance in the extraction of non-polar substances (triacylglycerides), has not proven effective in the extraction of polar substances. The efficient use of SC-CO₂/ethanol to extract and fractionate phospholipids from tuna shavings was therefore investigated. Extraction was performed at low pressure and temperature (17.7 MPa and 33°C) to avoid oxidation of polyunsaturated fatty acids. Phospholipids were extracted and fractionated with more than 5%-ethanol in SC-CO₂. To reduce the amount of consumed ethanol is an important problem to overcome in extracting on an industrial scale. The tuna shavings were soaked in the same volume of ethanol before extraction with neat SC-CO₂. For performance on an industrial scale, the extracting conditions were evaluated using a 10 mL-laboratory scale reactor. 182.8 kg of soaked tuna shavings was finally extracted and 4.2 kg of DHA-PL (DHA content = 29%) was obtained in a series of industrial processes.

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Study was made to clarify the decoloration mechanism of Orange II in the presence of horseradish peroxidase (HRP)-hydrogen peroxide (H₂O₂) in organic solvents/water systems. The decoloration rate constant of Orange II decreased in the presence of organic solvents. The highest decoloration rate constant was noted for the methanol/water system. The decoloration reaction of Orange II was found to proceed even at high concentrations of methanol, while this was not the case for alcohols solvents. Reaction of the HRP system was examined by following the changes in HRP oxidation states using the methanol, ethanol and 2-propanol/water systems. An intermediate - Compound III - was formed in the HRP oxidation cycle of ethanol/water and 2-propanol/water systems but did not in the methanol/water system. HRP oxidation states and reaction cycle are importantly involved in the decoloration mechanism of Orange II.

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Solvent isotope effects on the micellization behavior of fluorosurfactants have been investigated. The critical micelle concentration and the micelle ionization degree for 2-hydroxy-1,1,2,3,3-pentahydropefluoroundecyldiethylammonium halides in D₂O were lower than those in H₂O. The stronger hydrogen bonding in D₂O enhanced the micelle growth accompanying counterion binding.

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Methanol extract from Arctium lappa L. showed an inhibitory activity of α-glucosidase. The methanol extract was re-extracted with ethyl acetate and water. The ethyl acetate extract showed inhibitory activity. The inhibitory compound was isolated from the ethyl acetate extract and identified as sitosterol-β -D-glucopyranoside (1) by EI-MS, FAB-MS, IR, ¹H and ¹³C NMR spectroscopy. Compound 1 inhibited 97.3% of α-glucosidase activity at a concentration of 200.0 μ mol/mL, and the ID₅₀ (50% inhibition dose) value was 30 μ mol/mL. In addition, the inhibitory compounds from the ethyl acetate extract were also identified as methyl palmitate (2), methyl linoleate (3) and methyl linoleneate (4) by GC-MS analysis. Compound 2-4 inhibited 73.4%, 66.5% and 68.5% of α-glucosidase activity at a concentration of 200 μ mol/mL, and the ID₅₀ values were 52.8, 47.5 and 46.7 μ mol/mL. To research the structure-activity relationship, methyl steareate (5), methyl oleate (6), palmitic acid (7), linoleic acid (8), linolenic acid (9), stearic acid (10) and oleic acid (11) were also assayed.

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We investigated the bacteriolytic activity of alkaline protease BYA, a detergent protease, from Bacillus sp. Y. Protease BYA effectively lysed gram-negative bacteria and some gram-positive bacteria like Staphylococcus aureus and Staphylococcus epidermidis. The optimum pH of protease BYA was 8-9, and it was most active at 60°C, a temperature at which Deozyme, a commercial bacteriolytic enzyme, had lost most of its activity. The bacteriolytic activity and protease activities of protease BYA would be useful for removing bacteria from worn garments and production facilities.

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A novel alkyl ester of Vitamin C derivative, originated in a stable ascorbate derivative, sodium L-ascorbic acid 2-phosphate (VCP-Na), was chemically synthesized. The thermal stability, surface tension, distribution between organic and water phase, and in vitro skin permeability were evaluated. This monoalkyl ester derivative was identified as sodium isostearyl 2-O-L-ascorbyl phosphate (VCP-IS-Na) by UV spectra, infrared spectra, mass spectra, and nuclear magnetic resonance spectroscopy. The reaction afforded VCP-IS-Na in a high yield (60%). VCP-IS-Na exhibited satisfactory stability in neutral solution comparable to that of a typical stable derivative, VCP-Na. Increased skin permeability was superior to those of VCP-Na and ascorbic acid (VC). VCP-IS-Na that is susceptible to the enzymatic hydrolysis by tissue esterase and/or phosphatase released VC in the skin tissues. Thus, these characteristics indicate that the novel Vitamin C derivative presented here, VCP-IS-Na, may be effective pro-Vitamin C for skin care application.

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The compositions of the essential oil from woods of Prunus mume Sieb. et Zucc. (ume), have been investigated by capillary GC and GC/MS. The oil was found to contain 97 components, representing 92.41% of the total oil. The main constituents were 6,10,14-trimethyl-2-pentadecanone (15.83%), α-acorenol (9.36%), (Z)-α-bisabolene (7.49%), benzaldehyde (3.87%), isopropyltiglate (3.84%), terpinen-4-ol (3.41%).

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