We aerobic organisms are continuously exposed to an oxidative stress induced by active oxygen species and free radicals generated in vivo and in vitro. Recent experimental, clinical and epidemiological studies show that the free radical-mediated oxidations of lipids, proteins and DNA are involved in a variety of diseases, cancer and aging. We are protected against such oxidative stress by an array of defense systems composed of preventive antioxidants, radical-scavenging antioxidants, and repair and de novo antioxidants. Furthermore, the appropriate antioxidants are generated and transferred to the right site at the right time and in the right concentration. The actions of radical scavenging antioxidants are discussed, especially on vitamin E and nitric oxide in some detail.

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Regioselectively synthesized 6-O-acylsucroses as well as commercial sucrose esters were hydrolyzed by enzymatic cleavage of invertase to obtain 6-O-acylglucoses and an acylglucose fraction, respectively. 6-O-Octanoylglucose was prepared in 51% yield from 6-O-octanoylsucrose. Products were isolated and purified by column chromatography and characterized by TLC, ¹³C NMR and FAB/MS analyses. Surface active properties of the acylglucose fraction indicated particularly better capacity for lowering surface and interfacial tension, and foam stabilizing actions compared to the sucrose esters. The decrease in surface tension brought about by 6-O-acylglucose exceeded that by 6-O-acylsucrose. Water solubility of the former was less than that of the latter.

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Bleaching efficiency, amount adsorbed, κ-value and equilibrium amount adsorbed were measured to determine maximum adsorption capacity of adsorbent for the removal of chlorophyll (Chl) derivatives. Cosmetic-grade attapulgite (A5) was equivalent to standard activated clay (SAC) in optimum clay dose for bleaching alkali-refined rapeseed and soybean oils. The dose was 2.0% wt/wt for rapeseed and 1.5% wt/wt for soybean. Adsorption capacity should be evaluated based on the equilibrium amount adsorbed from the adsorption isotherm but not on the bleaching efficiency, amount adsorbed or κ-value. A5 was the same as SAC in equilibrium amounts of pheophytins (Phy) a/b adsorbed at low and high residual concentrations. A5 is thus useful for the adsorption removal of Chl and Phy as well as SAC.

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Amides of amino acids were hydrolyzed using hexose, pentose, and tetrose type glycolipids. They had a thiazolidine ring as the connecting group between a hydrophilic sugar moiety and a hydrophobic moiety (indirect type glycolipids) or did not have (direct type glycolipids). The former type glycolipid, in general, was more active than the latter type, and the activities, such as for substrate recognition and the hydrolyzing activity, were found to relate to the configuration of hydroxyl groups on C-2 and C-3 positions of the sugar moiety. That is, the L-threo type glycolipids showed the highest activities in both characteristics, and the D-threo type showed the lowest activities. The erythro type glycolipids exhibited moderate activities.

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Glycolipids classified into two categories were synthesized and applied, as hydrolase models, to the hydrolyses of p-nitro-anilides of amino acids ; one had a sugar group at the end (hydrophilic part) of a glycolipid molecule and the other had a histidine group bonded to ω-position of the sugar moiety. Both types of glycolipids could recognize the kinds of amino acids like α-chymotrypsin, but the combination system of both categories of glycolipids only recognized them in different modes. The combination system, however, distinguished the D, L-configuration of amino acids better than other glycolipids. In particular, it distinguished D, L-alanines perfectly like an enzyme. The recognition mechanism is discussed.

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Two strains of yeasts : Rhodotorula gracilis 2 and Trichosporon cutaneum 1 were selected from ten strains for use in the present study. After preliminary culturing on the Wickerham [W] synthetic medium the strains were considered maximally oleaginous. The waste carrot juice remaining after production of β-carotene was used for the culture of oleaginous yeasts.
The lipids obtained from the cultured yeast biomass were examined for acylglycerols, free fatty acids, phospholipids, sterols and nucleic acids content.

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Quality and quantity of lipids biosynthesized by the two yeast strains : Rhodotorula gracilis 2 and Trichosporon cutaneum 1 were compared.
The yeasts were cultured on the synthetic Wickerham [W] medium and media based on the carrot juice for 72, 96, and 120 h.
Fractions of diacylglycerols, triacylglycerols as well as fatty acids, free fatty acids, phospholipids, sterols occurring in them, and compounds constituting sterols, were quantitatively determined.

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Anionic surfactants each containing two tail-chains with a ferrocenyl group at either end, the sodium salt of bis (11-ferrocenyl undecyl) sulfosuccinate and the sodium salt of bis (5-ferrocenylpentyl) sulfosuccinate, were prepared in six reaction steps using ω-bromoalkanoic acid as the starting material. The intermediates and the products were characterized by IR, ¹H NMR, Mass spectra, and elemental analysis. Krafft point, surface tension and electrochemical property were also determined.

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