The phase behavior of mixed solutions of (11-ferrocenyl)undecyltrimethyl-ammonium bromide (FTMA⁺), a redox-active cationic surfactant, and sodium dodecylbenzenesulfonate (SDBS), an anionic surfactant, was investigated in detail, and the mechanisms of spontaneous vesicle formation and the control of reversible formation of vesicles through the redox reaction of FTMA⁺ in the mixed system were also examined. Differential interference optical microscopic observations, particle size measurements, and trapping efficiency measurements revealed that various types of aggregates including mixed micelles, vesicles, and liquid crystals are formed in the system depending on the mixing ratio of FTMA⁺ and SDBS. Ultracentrifugal measurements showed that the composition of bimolecular membranes composed of FTMA⁺ and SDBS differs from the initial surfactant mixing ratio and changes depending on the initial mixing ratio. Surface tension measurements indicated an important contribution of the formation of a pseudo-double chain-type complex through the electrostatic interaction between FTMA⁺ and SDBS to spontaneous vesicle formation. In addition, the existence of a benzyl group in the anionic surfactant was suggested to be important for the pseudo-double chain-type surfactant to take the orientation favorable to vesicle formation.

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Examination was made of the properties of aqueous solutions of cationic fluorosurfactants based on data for the fluorescence quenching of quinoline and acridine derivatives. The fluorosurfactant possessing a chloride counterion gave higher CMC and micellar counterion dissociation compared with those containing bromide. Micellar counterion dissociation was noted to slightly decreased with increase in NaCl but significantly to do so to less than 30 and 75 mM NaCl for C₈F₁₇CH₂CH(OH)CH₂NH(C₂H₅)₂Cl and C₈F₁₇CH₂CH₂NC₅H₅ Cl, respectively. Change in 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ) fluorescence spectra with hydrogenation served as basis for determining the site of solubilization in micellar solution. Dissolved SPQ in water bulk phase underwent instant reduction with the addition of NaBH₄, though SPQ in fluorosurfactant systems showed virtually no reduction owing to solubilization of SPQ in vesicles.

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We performed a clinical study using healthy male and female subjects who had slightly elevated cholesterol levels in their serum to examine the effects of food tablets containing apple polyphenols (Applephenon^®), which are effective for improving serum cholesterol concentrations in rats, on lipid metabolism in humans. The total period of this study was four weeks and we obtained blood samples at week 0 and week 4. Total cholesterol levels of the intervention groups decreased significantly and dose-dependently compared with that of the control group. We also found LDL-cholesterol decreased significantly and HDL-cholesterol increased. No abnormalities were detected in biochemical examinations of any of the subjects during the test period. We concluded that the study product is useful as a food additive that improves serum cholesterol concentrations. Such improvement is expected to decrease the risk of atherosclerosis for people with a slightly elevated total cholesterol level.

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We assessed the protective effect of the dietary antioxidants, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) against acetaminophen (APAP)-induced hepatotoxicity. After giving diets containing BHA (0.5%), BHT (0.5%) to male Wistar rats for 7 days, they were fasted for 16 h and then intraperitoneally injected with APAP (0.5g/kg). The severity of the hepatic injury was inferred from the plasma alanine aminotransferase and aspartate aminotransaferase levels 24 h later. The results indicated that BHA and BHT significantly protected the rats against APAP hepatotoxicity. Upon investigating the mechanism of the protective action of BHA and BHT, the hepatic glutathione (GSH) levels decreased to the same degree in the APAP, BHA + APAP, and BHT + APAP groups 2 h after the injection of APAP, while the GSH levels started to recover in all groups at 6 h, but increasing faster in the BHA + APAP and BHT + APAP groups than in the APAP group. As compared with the control group, the hepatic cytochrome P450 (CYP) 2E1 levels tended to be about 20% higher in the BHA + APAP group from 2 to 24 h, and about 30% higher in the BHT + APAP group only at 24 h. These results suggest that the protection against APAP-induced hepatotoxicity provided by BHA and BHT is partly due to rapid recovery of the hepatic glutathione levels but does not involve changes in the CYP2E1 levels.

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Positional distribution of fatty acids in triacyl-sn-glycerols (TAG) has been investigated for Artemia franciscana nauplii used in marine fish larviculture as an important live food. For enhancement of essential highly unsaturated fatty acids, the nauplii were enriched for 4 to 24 h with two emulsions containing fish roe polar lipids (PL), (i) a mixture of bonito head oil TAG and salmon roe PL concentrate (88:12, wt/wt) and (ii) an unmixed salmon roe PL concentrate. In TAG isolated from all enriched Artemia nauplii, docosahexaenoic acid (DHA) was preferentially esterified in the sn-3 position (0.7-22.9 mol%) followed in sequence by the sn-2 (0.1-7.5 mol%) and sn-1 (0.0-4.6 mol%) positions. This distribution pattern was the same as previously observed for enrichment with bonito head oil TAG free from salmon roe PL. Addition of fish roe PL to DHA-rich fish oil enricher does not seem to practically affect the distribution pattern of DHA characteristic of Artemia nauplii.

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Nine sulfate-type hybrid surfactants with an ethylene spacer in their molecule, C_mF_2m+1C₂H₄CH(OSO₃Na)C_nH_2n+1 (FmEHnOS: m = 4, 6, 8; n = 3, 5, 7), were synthesized. FmEHnOS were obtained in a yield higher than those for the hybrid surfactants previously synthesized. While FmEHnOS were hardly susceptible to hydrolysis in aqueous weakly acidic through strongly alkaline media, these surfactants were hydrolyzed in highly acidic media to give alcohol derivatives, FmEHnA. They were highly water-soluble and highly surface-active. Their critical micelle concentrations (cmc) determined by surface tension measurements were about 3.5 times higher than those of sulfate-type hybrid surfactants with a benzene ring spacer, C_mF_2m+1C₆H₄CH(OSO₃Na)C_nH_2n+1 (FmPHnOS: C₆H₄ = p-phenylene), and the cmcs were found to obey the Klevens’ rule. Changes in the chemical shifts of ω-CF₃ and ω-CH₃ groups in the NMR spectra of the newly synthesized surfactants at different concentrations suggested that the fluorocarbon and hydrocarbon chains in F4EH3OS micelles undergo an intramicellar phase separation. Thermoresponsive surfactant gel formation was observed for 10 wt% F8EH3OS solution.

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New troponoid liquid crystals with bis(tropon-2-yl)-4,4’-azobisbenzoate core were prepared. Compound (1) had enantiotropic nematic and/or smectic C phase. The crystals of 1a had intermolecular π-π interactions between azobenzene planes and between tropone rings. The nematic liquid crystal (1a) did not form any layer structure in crystal state. X-ray diffraction studies revealed that 1c and 1d formed the tilted layers in the smectic C phase.

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Seven glycosides were isolated from African dietary leaves, Hibiscus sabdariffa. Their structures were determined based on UV, MS, ¹H-NMR and ¹³C-NMR spectroscopic data as kaempferol 3-O-rutinoside [1], kaempferol 3-O-glucopyranoside [2], quercetin 3-O-rutinoside [3], citrusin C [4], 2,3-dihydro-2-(4′-hydroxy-3′-methoxyphenyl)-3-β-D-glucopyranosylmethyl-7-hydroxy-5-benzofuranpropanol [5], corchoionoside C [6], and trans-carveol 6-O-β-glucopyranoside [7]. In the bioassay with superoxide scavenging activity, 1-BuOH extract, acidic components, neutral components, compound 3 and aglycone of 3 (3a) showed strong activity. And in the tyrosinase inhibitory activity, aglycone of 1 (1a) and aglycone of 3 (3a) showed good inhibition. As a result, we considered that Hibiscus sabdariffa may be related to the longevity, and their 1-BuOH extract was found promising as a cosmetic agent. The presence of compounds 4-7 in the leaves of Hibiscus sabdariffa is reported here for the first time.

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