LB films composed of polymer compounds are of interest as potential sources of new materials. Various factors influencing the formation of stable polymer monolayer are reviewed from a difference from low molecular weight monolayers. As a new type of polymer LB films, fluorinated polymer LB films with excellent surface properties such as water repellency and lubricant, and polymer LB films containing organic magnetic functionality are discussed.

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High resolution nuclear magnetic resonance (NMR) spectroscopy is an effective means for the determination of trans fatty acid content in hydrogenated vegetable oils. The trans fatty acid content is calculated from the number of trans double bonded carbons and average molecular weight derived directly from the spectrum of ¹³C-NMR and ¹H-NMR, respectively. Allylic carbons were used to estimate the absolute number of trans double bonded carbons. NMR results of hydrogenated oils were compared with those obtained by IR method. Correlation coefficient of the data between ordinary IR method and NMR method was r²=0.995, and the regression equation was Y=0.986X+1.37, where X was the IR results. The trans fatty acid measured by NMR was ±6% of error, when corrected with proposed regression equation, except for two samples in which trans fatty acid contents were below 6%.

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The time parameter for saturated triacylglycerol was determined by reversed-phase high performance liquid chromatography using a light scattering detector and acetonitrile/dichloromethane or acetonitrile/acetone mixture solvent as the mobile phase. The relationship between carbon number in a triacylglycerol molecule acyl chains and the retention time was accurately derived from the quadratic curve on a log-linear graph.
The retention times of species of unsaturated triacylglycerols were then examined under the same conditions. The equivalent carbon number (ECN) of the each unsaturated triacylglycerol was calculated and the manner in which the retention time was related to the three acyl chains in a triacylglycerol molecule was determined. The relationship between the mixing ratio of elution solvents and retention time was also examined.

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Commercially available butters, cheeses from cow, goat, ewe and water buffalo milk, fermented milk, condensed milk, creams and ice creams in Japan were collected from October to December, 1995 for determination of trans fatty acid.
1) In 34 domestic butters, mean total trans fatty acid was 4.1% (range, 3.0% to 5.7%) of total fatty acid, which is consistent with the previously reported value for domestic cow milk.
2) In 88 cow natural cheeses (32 domestic and 56 imported), mean total trans fatty acid was 5.7% (range, 4.0% to 8.9%) of total fatty acid. In imported cow natural cheeses, total trans fatty acid of products from the United Kingdom (6.1%), Australia (6.4%) and New Zealand (6.8%) exceeded that from the United States (4.9%) and Canada (4.3%).
3) In imported 28 brands of goat cheeses, 24 brands of ewe cheeses and 3 brands of water buffalo cheeses, mean total trans fatty acid was 4.3%, 6.2% and 6.4% of total fatty acid, respectively.
4) Mean total trans fatty acid of fermented milk (12 samples), condensed milk (3) and creams (16) was essentially the same in all cases (range, 4.5% to 4.9% of total fatty acid). Mean total trans fatty acid of domestic (9) and imported (12) ice creams was 4.4% and 6.4% respectively, the difference between these products being significant.

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Docosahexaenoic acid ethyl ester (DHA-E) was refined by Supercritical Fluid Chromatography (SFC) using silver-loaded spherical clay material [SC(Ag)] in the stationary phase. High purity DHA-E (99%) could thus be recovered to a greater degree by using the oil with high DHA-E content, and by enlarging the preparative column. This DHA-E was found to have reagent grade purity, and purification was not attended with deterioration. The time required for purification could be shortened by changing the purity of DHA-E from 99% to 95%, and more DHA-E per day of higher purity could thus be obtained by this new method.

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Gas chromatography-microwave-induced plasma atomic emission spectrometry (GC-MIP-AES) was shown an effective means for determining the empirical formulae of fatty acid (FA), monoacylglycerol (MG) and diacylglycerol (DG) trimethylsilyl (TMS) ester (or ether) derivatives. Negative interference by silicon was demonstrated on an oxygen emission chromatogram. Negative interference and positive oxygen emission intensity decreased with increase in the rate of helium make-up gas flow. At optimal helium make-up gas flow (160mL/min), the oxygen number of the empirical formulae of FA, MG and DG-TMS derivatives were determined within ±0.3 atoms of theoretical formulae, and relative standard deviation (%) was less than 3.1% for FA-TMS, 4.1% for MG-TMS and 4.5% for DG-TMS.

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This study was conducted to examine the long-term effects of dietary diacylglycerols (DG) on body fat in man. The fatty acid composition of DG used in this study was similar to that of triacylglycerols (TG). Healthy male subjects (27-49 years) were supplied their usual diet with 50g TG (15g for breakfast, 15g for lunch and 20g for dinner) a day. After a 4-week TG diet period, the subjects were divided into two groups to be supplied their usual breakfast with either 10g lipids of DG or TG. Every 4 weeks, the subjects visited the clinic for blood sampling, and had abdominal fats and liver fat determined by computed tomography (CT). In the DG diet group, body weight, body mass index and waist hip ratio decreased significantly after 12 week ingestion compared to the TG diet group. Fat in the abdominal region at the end of the DG diet decreased more than the end of the TG diet. The results for the liver CT/spleen CT ratio which is an indicator of liver fat content showed that fat in the liver had decreased significantly 8 and 12 week after ingestion in the DG diet group. A decreasing effect of DG on the amount of lipid of the liver in the DG diet group was clearly observed in the subjects with a greater reduction in free fatty acid in the serum. On the other hand, the amount of ketone body in the DG diet group was inclined to be higher than that in the TG diet group. Glucose and insulin in the serum increased significantly after the TG diet, but it did not increased during the period of examination in the DG diet group. These results showed that the DG diet improved insulin sensitivity and reduced visceral and liver fat by increasing β-oxidation in the liver. It can be considered that DG is an ideal source of energy, assuring less fat accumulation by decreasing serum insulin and fatty acids compared to TG.

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Campholene derivatives obtained by the crossed aldol condensation of Campholene aldehyde (2) with ketones, are quite useful for the synthesis of perfumes. (2) was prepared by the isomerization of α-Pinene oxide (1) in the presence of a solid acid catalyst.
The synthesis of 5-(2, 2, 3-trimethyl-3-cyclopenten-1-yl)-3-penten-2-one (3) was conducted by a one-pot procedure in a flask containing (1), acetone, solvent, solid acid catalyst and solid base catalyst.
A method for the facile synthesis of (3) was developed using KF/H-Y330 as a solid acid catalyst and Sr(OH)₂·8H₂O as a solid base catalyst. Other ketones (2-butanone, 3-pentanone, cyclopentanone) could also be used for synthesizing various campholene derivatives with these catalysts.

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