Abstracts of J. Oleo Science Vol. 50, No, 3

REVIEW

Microcapsules: Their Science and Technology, Part III. Industrial, Medical, and Pharmaceutical Applications,
Tamotsu KONDO, Professor Emeritus, Ph.D.,
Science University of Tokyo, Present address: 2-17-16 Midori-cho, Tanashi-shi, Tokyo 188-0002, JAPAN.
Industrial, medical, and pharmaceutical applications of microcapsules are described. Pressure-sensitive copying paper is a typical example of their industrial applications while sustained drug release devices are a representative example of their medical and pharmaceutical applications.
J. Oleo Sci. Vol. 50, 143-152 (2001).

REGULAR PAPERS

Analytical Method for Routine Quantitative Analysis of Plant Stanols in Stanol Ester Spread,
Kenneth B. SHAPIRO¹, Li LI¹, Candyce A. SECOR¹ and Michihiro SUGANO²,
¹: McNeil Consumer Healthcare, Research and Development Laboratories, 7050 Camp Hill Road, Fort Washington, PA 19034, USA and ²: Laboratory of Food Functionality, Faculty Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, 3-1-100 Tsukide Kumamoto-shi, Kumamoto 862-8502, JAPAN.
Clinical studies on foods containing plant stanol ester repeatedly demonstrate 10-14% reduction in serum LDL-cholesterol. Since plant stanols are the agents responsible for the cholesterol-lowering activity of stanol ester, an analytical method was developed for quantitative and routine analysis of plant stanol content in spreads containing clinically-effective levels of plant stanol ester. Analysis of plant stanols in stanol ester spread is achieved using direct saponification in which stanol ester spread is saponified directly with ethanolic potassium hydroxide without prior separation of the lipid fraction. Plant stanols are then extracted with hexane and derivatized to trimethylsilyl ethers. Plant stanols are analyzed by Gas Chromatography and quantified against cholestanol as the Internal Standard. Analysis of sitostanol, campestanol and total stanol content in spreads supplemented with stanol ester was found to be linear (r²>0.999), accurate (99-102% recovery), precise (RSD<2.0%) and rugged between laboratories. These results demonstrate that the analytical methods for plant stanol determination are validated for routine quantitative analysis of spreads containing plant stanol ester.
J. Oleo Sci. Vol. 50, 153-158 (2001).

Preparation and Surface-Active Properties of Complexane-type Trimeric Surfactants from Tris(2-aminoethyl)amine,
Emika ONITSUKA¹, Tomokazu YOSHIMURA¹, Yoshifumi KOIDE¹, Hideto SHOSENJI¹ and Kunio ESUMI²,
¹: Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kumamoto University, 2-39-1, Kurokami, Kumamoto-shi, Kumamoto 860-8555, JAPAN and ²: Department of Applied Chemistry, Institute of Colloid and Interface Science, Science University of Tokyo, 1-3, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, JAPAN.
Complexane-type trimeric surfactants of tris(1-carboxyalkyl-2-aminoethyl)amine (3R_ntata ; n means alkyl chain length, n=6-14) having three alkyl chains and three hydrophilic groups were prepared by the reaction of tris(2-aminoethyl)amine and 2-bromoalkanoic acid and examined for surface activities such as surface tension, emulsification and interfacial tension. Critical micelle concentration (cmc) of 3R_ntata shifted to lower concentration with increasing alkyl chain length. The cmcs of 3R_ntata with n of 10-14 were lower by about 1-2 orders of magnitude than those of complexane-type monomeric surfactant of 2-aminoalkanoic acid (R_nNAc) and dimeric surfactant of N, N"-bis(1-carboxyalkyl)diethylenetriamine 2R_ndtda) with the same alkyl groups. In the case of R₁₂, 3R_ntata gave about twice cmc of trimeric surfactant of (N-1-carboxyalkyl-2-aminoethyl)alkyllamine (3R_ndtda) having three alkyl chains and two hydrophilic groups. Surface tension at each cmcs of 3R₁₀tata, 3R₁₂tata and 3R₁₄tata was 33.0, 26.9 and 29.6 mN m^-1, respectively. 3R₁₂tata and 3R₁₄tata gave more efficient in lowering the surface tension than R_nNAc and 2R_ndtda. The values of cross-sectional molecular area (A) of 3R_ntata with n of 10-14 were 42-75 Ų. They were extremely small in comparison with three times of A of R_nNAc. The aqueous solutions of 3R_ntata were emulsified by shaking with toluene. Highly stable oil-in-water type emulsion was formed by using 3R_ntata with n of 10-14 and the degree of emulsification was kept 60% after 20 h. Interface between the aqueous solutions of 3R₁₀tata, 3R₁₂tata and 3R₁₄tata and toluene gave the interfacial tension of 1, 1 and 6 mN m^-1, respectively.
J. Oleo Sci. Vol. 50, 159-164 (2001).

Synthesis and Characterizations of a Porphyrin Dimer Having a 2,6-diacylpyridyl Group as a Spacer between Two Porphyrin Units,
Yasuhiro SUGA, Takashi ARIMURA, Seiji IDE, Hideki SUGIWARA, Shigeo MURATA and Masanori TACHIYA,
National Institute of Materials and Chemical Research, COE laboratory, Higashi 1-1, Tsukuba, Ibaraki 305-8565, JAPAN.
The synthesis of a porphyrin dimer with a 2,6-diacylpyridyl group as a recognition site was accomplished by the coupling of 2,6-diaminopyridine and two porphyrins with a 4'-ethoxycarbonylbiphenyl substituent at a meso-position of the porphyrin ring. By comparing the absorption spectrum of the obtained porphyrin dimer in CH₂Cl₂ with that of the corresponding porphyrin monomer, no remarkable interaction between two zinc porphyrin units was indicated. ¹H NMR studies revealed that hydrogen bonding interactions of the 2,6-diacylpyridyl group in the porphyrin dimer serve to form a novel supramolecular assembly in the presence of naphthalenediimide compound.
J. Oleo Sci. Vol. 50, 165-171 (2001).

Surface Tension Measurements with High Accuracy: Investigation of Accuracy for Automatic Measurements by the Drop Volume Method,
Hitoshi MATSUKI¹, Yuji YAMASHITA² and Shoji KANESHINA¹,
¹: Department of Biological Science and Technology, Faculty of Engineering, The University of Tokushima, 2-1 Minamijosanjima-cho, Tokushima 770-8506, JAPAN and ²: Yamashita Technology System Limited Company, 551-4 Kagasuno, Kawauchi-cho, Tokushima 770-0130, JAPAN.
Surface tension is difficult to measure with high accuracy. This parameter was measured for pure water to determine conditions that would permit high accuracy. Sources of error in assessing stability, variance, reproducibility and time-dependency of surface tension were sought. The glass syringe, differences in inner and outer temperatures of the cell and its inner pressure, etc. were found to affect this parameter. With attention to these factors, greater accuracy was achieved. Use of a glass syringe and holder with exact control of temperature led to maximum elimination of error. The surface tension of pure water, surfactant solutions and volatile organic liquids were measured and compared with previous values. There was less variation and the results were much more reproducible. High accuracy is thus possible with elimination of sources of error. Significant interfacial phenomena such as phase transition in adsorbed film, not observed by usual surface tension measurement apparatus, may thus be effectively studied through use of surface tension obtained with the present apparatus.
J. Oleo Sci. Vol. 50, 173-183 (2001).

Sterol Content Determination in Buckwheat,
Takashi TANAKA, Yasuhisa HAYASHI and Suguru TAKATSUTO,
Department of Chemistry, Joetsu University of Education, 1 Yamayashiki-machi, Joetsu-shi, Niigata 943-8512, JAPAN.
Sterol content in tartary buckwheat (Fagopyrum tataricum Gaertner) achenes (n=3) and common buckwheat (Fagopyrum esculentum Moench) achenes (n=11) were examined by GC-MS. All cultivars were found to have essentially the same major sterol content (campesterol, stigmasterol, sitosterol and isofucosterol) and regional variation was small for either achene. Sitosterol was most abundant at 70%-80% of bulk sterols and other bulk sterols in the achenes were campesterol, stigmasterol and isofucosterol. Trace amount of sterols were present in each achene. Besides four major sterols, 13 sterols from an ester and 9 free sterols were detected in tartary buckwheat. 9 sterols from an ester and 11 free sterols were confirmed present in common buckwheat.
Bulk sterol content in both 'free' and 'bound' lipids of achenes, leaves and stems of plants was determined by GC. Sterol content of tartary buckwheat achene was 82.5 mg/100 g achene (average, n=3), while that of common buckwheat achene 100.2 mg/100 g achene (average, n=3). Sterol content of leaves was twice as much and that in stems, basically the same as in the achenes. Sterol content was found here for the first time to be high not only in 'free lipid', but 'bound lipid' as well of leaves and stems of buckwheat.
J. Oleo Sci. Vol. 50, 185-190 (2001).

Synthesis and Biodegradability of Monoalkylated Caprolactone Copolymers,
Hiroyuki SHIRAHAMA¹, Naoya KANAMORI² and Hajime YASUDA²,
¹: Center for Technology Research & Development, Hiroshima University, 3-10-31 Kagamiyama, Higashi-Hiroshima, 739-0046, JAPAN and ²: Department of Applied Chemistry, Faculty of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima, 739-8527, JAPAN.
The authors first synthesized 4-alkylated caprolactones (4ACLs) from 4-alkylcyclohexanones via Baeyer-Villiger reaction. The 4ACLs obtained from 4-methyl-, 4-ethyl-, and 4-t-butylcyclohexanone were abbreviated as 4MCL, 4ECL, and 4BCL, respectively. Copolymers of L-lactide (L-LA) with 4ACL or e-caprolactone (CL) and homopolymers of the monomers were prepared using tin (II) octylate as catalyst. Thermal and NMR analyses of the polymers indicated poly(L-LA) and poly(CL) to be crystalline, while poly(4ACLs) to be noncrystalline polymers, and L-LA/4ACL copolymers to be crystalline or noncrystalline polymers depending on composition and to have random sequences. Flexibility (elongation at break) of the copolymers was much improved compared to poly(L-LA), with melting temperature and mechanical properties of poly(L-LA) maintained as much as possible. The biodegradability of the polymers by enzymes (Proteinase K, lipoprotein lipase) and in seawater was examined. Enzymatic degradation of copolymers followed the order, copoly(L-LA/CL)>copoly(L-LA/4MCL)>copoly(L-LA/4ECL)>copoly(L-LA/4BCL), suggesting that the greater steric hindrance of alkyl side chains of 4ACL, the less was degradability. ¹H NMR spectra of water-soluble degraded products of L-LA/4MCL copolymer indicated that Proteinase K ultimately degraded the copolymer into hydroxy acids (viz., L-lactic acid and 6-hydroxy-4-methylcaproic acid) of its constitutive units.
J. Oleo Sci. Vol. 50, 191-200 (2001).

NOTES

Sterol Content Determination in Wheat Flour,
Takashi TANAKA, Nahoko KOSUGA and Suguru TAKATSUTO,
Department of Chemistry, Joetsu University of Education, 1 Yamayashiki-machi, Joetsu-shi, Niigata-ken 943-8512, JAPAN.
Determination was made of sterol content in wheat flour. Based on direct GC-MS comparison with authentic samples and mass spectral data, fifteen 4-desmethylsterols, four 4-monomethylsterols and two 4,4-dimethylsterols, were confirmed present in the flour, along with three terpene alcohols, and the amount of each was computed. The content of each of five major 4-desmethylsterols (campesterol, campestanol, stigmasterol, sitosterol and sitostanol) in the flour and wheat seeds was determined by GC.
J. Oleo Sci. Vol. 50, 201-205 (2001).

Surface Active Agent-Catalysed Conversion of Saccharides to Furfural Derivatives,
Kazuhiko HAMADA¹, Hiroshi YOSHIHARA² and Gohfu SUZUKAMO³,
¹: Organic Synthesis Laboratory, Sumitomo Chemical Co. Ltd., 2-10-1, Tsukahara, Takatsuki-shi 569-1093, JAPAN, Current address : Central Research Laboratory, Pias Corporation, 3-1,1-chome, Murotani, Nishi-ku, Kobe 651-2241, JAPAN, ²: Organic Synthesis Laboratory, Sumitomo Chemical Co. Ltd., 2-10-1, Tsukahara, Takatsuki-shi 569-1093, JAPAN, Current address: Oita Branch, Sumika Technoservice Corporation, 2200, Oaza-Tsurusaki, Oita-shi 870-0106, JAPAN and ³: Organic Synthesis Laboratory, Sumitomo Chemical Co. Ltd., 2-10-1, Tsukahara, Takatsuki-shi 569-1093, JAPAN.
This paper presents a method for the industrial preparation of 5-substituted furfurals, potential as agricultural chemicals, dehydrating saccharides with hydrochloric acid in the presence of catalytic amounts of surface active agents.
J. Oleo Sci. Vol. 50, 207-209 (2001).