The chemistry of the metal complexes with long alkyl side chains is briefly reviewed. The introduction of long alkyl side chains to the metal complexes appends some new properties, such as extremely high solubility towards organic solvents, tendency to aggregate, ability to form liquid crystals, etc. The methods to introduce long alkyl side chains to the metal complexes together with the methods to characterize these complexes are briefly described.

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The cytoplasmic membranes (CM) and thylakoid membranes (TM) were isolated from the thermophilic cyanobacterium Synechococcus elongatus. These membranes contained similar rates of polarlipid classes; monogalactosyldiacylglycerol (MGDG) (ca. 58 %), digalactosyldiacylglycerol (DGDG) (ca. 16 %), sulfoquinovosyldiacylglycerol (SQDG) (ca. 11 %) and phosphatidylglycerol (PG) (ca. 8 %). In either membranes, about 50 % of the total lipid consisted of pigments, of which about two thirds was chlorophyll-a in TM, while in CM chlorophyll-a was at a trace amount. The remains of the pigmentswere supposed to be carotenoids in either membranes. Of the fatty acids of the lipids in either membranes, palmitic acid (16 : 0) comprised more than 50 %, oleic acid (18 : 1) about 20 %, cis-9-hexadecenoic acid (palmitoleic acid; 16 : 1) about 15 %, stearic acid (18 : 0) about 10 %. Comparing with mesophilic cyanobacteria, the Synechococcus membranes contained more pigments, less PG and more saturated fatty acids, and showed simpler profiles of fatty acid compositions.

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An improved microscale procedure for determining phospholipid composition by two-dimensional thin-layer chromatography (TLC) in conjunction with phosphorus analysis was established. For the quantitative determination of lipid phosphorus, an organic phosphate is converted to an inorganic phosphate by perchloric-nitrate digestion, which then made into an ammonium phosphomolybdate complex.Absorbance of the complex extracted with ethyl acetate/butyl acetate (9 : 1, vol/vol) was determined at 310 nm. A liner relationship between 0.051.00μg of phosphorus and absorbance was found.
This two-dimensional TLC method was carried out using synthesized P, P'-bis (1, 2-dihexadecylether-sn-glycerol-3-) -pyrophosphate as the internal standard. It was possible to analyze the phospholipid composition of soybean lecithin by this method using only 50μg of crude lipid extract.

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The influence of butylhydroxylanisol (BHA) on the thermotropic behavior of phsopholipids was studied by differential scanning calorimetry (DSC). It was found to differ according to the polar headgroup of phospholipid. In the presence of dipalmitoylphosphatidylcholine (DPPC), BHA decreased the transition temperature (Tm), broadened the peak, and decreased the enthalpy of the transition. It caused the elimination of subtransition and pre-transition. With dipalmitoylphosphatidylethanolamine (DPPE), BHAdecreased Tm and broadened the peak, and two new subtransitions appeared. With dipalmitoylphosphatidylglycerol (DPPG), BHA had no influence on the profile. With a DPPC/DPPE mixture, BHA induced phase separation and the formation of a DPPC-rich domain. With a DPPC/DPPE mixture and the phospholipids of Escherichia coli, BHA had greater influence on the more fluid phospholipid species. BHA would thus appear to interact with a phospholipid near its polar head group, thereby affecting lipid packing.

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Methyl laurate used in this study as an original fatty ester) was easily converted to a 1 molar SO₃ adduct (first intermediate) by adding SO₃ at-20°C. This intermediate was found to be in equilibrium with the original ester. The energy of addition of SO₃ to form the intermediate was about 14 kcal/mol based on exchange rates of the equilibrium.
Sulfonation of the α-position of an ester occurred not on the original ester but on the first intermediate to give a 2-molar SO₃ adduct (second intermediate). The α-sulfonation followed kinetically the second order for the first intermediate and had an activation energy of about 25 kcal/mol.
The rate of the final reaction to the α-sulfofatty acid methyl ester (α SFM) from the second intermediate depended on the amount of co-existing ester.
According to the experimental results, the sulfonation mechanism for α SFM is proposed.

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We describe a new method for determination of phosphatidylcholine and lysophosphatidylcholine in partial hydrolyzed phospholipids. The method consists of fractionation of cholinecontaining phospholipid by preparative TLC and enzymatic determination based on the cholineoxidase-phenol method. The method affords better specificity and shorter time than the conventional two-dimensional TLC method are possible. Reproducibility (CV<3 %) and good agreement with those of two-dimensional TLC method were confirmed. This method is thus applicable to the determination of lysophosphatidylcholine and phosphatidylcholine in partially hydrolyzed phospholipids.

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The degree of lytic action due to interactions between nonionic surfactants and liposomes was determined in terms of affinity for lipid membranes. The solubilization potential of some surfactants toward liposome membranes was estimated based on physicochemical measurements such as fluorometry to detect the release of fluorescent markers (calcein) from liposomes, turbidimetry in suspensions and surface tensiometry. The lytic action of the alkyl poly (oxyethylene) ether (POE) toward lipid membranes was greatest when the alkyl and ethylene oxide chain lengths were 12 and 8, respectively. The lytic action of nonionic surfactants with various hydrophobic portions (hydrogenated caster oil POE ethers, cholesteryl POE ethers, nonylphenyl POE ethers and POE stearate) was found to depend on structure. Maximum activity in each homologous series was 1.2 I.O.B. (Inorganic Organic Balance).
The critical micelle concentrations (cmc) of dodecyl POE (5) and POE (10) ether in the absence and presence of liposomes were determined using a surface tension meter. Addition of liposomes caused cmc of the surfactants to increase. Dodecyl POE (5) ether causes marker release at lower concentration than cmc without change in turbidity. Dodecyl POE (5) ether concentration increase further, marker release from liposomes greatly increase minor change in turbidity. For dodecyl POE (10) ether, marker release started from cmc with decrease in turbidity. The lytic action of nonionic surfactants on liposomes would thus appear related to their capacity formixed micelle formation with phospholipids.

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Several surfactants were derived from highly branched carboxylic acids, prepared by the carbonylation of isobutylene oligomers. Surface and forming properties, and wetting ability toward a felt chip were examined. Ionic surfactants such as sodium sulfonate, sodium sulfates, quaternary ammonium salts, and the betaine derivative showed good ability for lowering surface tension and excellent wetting ability. Micelle forming properties were relatively poor compared to the corresponding linear analogs. To characterize the highly branched structure of hydrophobic group in surfactants several connecting groups between the hydrophilic group and the highly branched moiety were investigated for series of sodium sulfate derivatives. Micelle forming properties improved by increase in the hydrophobicity of the connecting chains without decrease in water solubility. The esters of carboxylic acid and the poly (ethylene glycol), a nonionic surfactant, could be easily prepared and were found to have the qualities mentioned above due to their highly branched structures.

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Capillary gas liquid chromatography (GLC) was conducted to determine fatty acid methyl ester and TMS sterol content in four different vegetable oils : soybean, cottonseed, sunflower, and grapeseed oils. GLC was efficient not only for attaining high resolution but also in detecting minor constituents of the oils. Each oil could be distinguished from the others by comparing fatty acid and sterol patterns. When there was case of similarity, the relative ratio of as the ratio of polyunsaturates % to total saturates % as well as the ratio of β-sitosterol to the sum of campesterol and stigmasterol could be used to accurately evaluate the authenticity of each oil.

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The influence of the heating method on the deterioration of frying oil was examined using three commercial fryers with different methods of heating : the electromagnetic heating system (M), electroric heating system (E), and a heating system with gas burner (G).
Soybean oil was heated at 180°C in the three fryers for 49 h (every day 7 h). The degree of oil deterioration was determined and expressed in terms of viscosity, carbonyl and acid content, and optical density. The rate of deterioration was found to increase in the order of M, E and G. The temperature of the surface of heating tube would thus appear to influence the rate of deterioration.
In the case of a small thermal load, the rate of oil deterioration was essentially the same for all three heating methods.

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