Mielkes Oil World Journal of West Germany published the special issue “Oil World 19582007” at the end of 1988. This report introduced the trend of oilseeds, oilmeals and oils and fats in the world according to the special issue. The review covered the fundamental factors affecting the oil and fat resources, the trend of crucial countries and the market situation on livestock, 12 oilmeals, 17 oils and fats and 10 oilseeds in the aspect of the long term trend from the past 30 years to the future 20 years. Recent information on plant breeding of major plant oil reseurces was also reviewed.

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The thermally oxidative deterioration of soybean oil was assessed during cooking typical of that in a Japanese home. A large quantity of fresh soybean oil was heated in a steel pan at 180±2°C for 30h, and an aliquot of the oil was withdrawn periodically and then heated as a thin layer in a frying pan at 180±2°C for 5 or 10min. Polymers and polar material content was determined by gel permeation high performance liquid chromatography using a differential refractometer as a detector, and thin-layer chromatography with a hydrogen-flame ionization detector. Chemical characteristics (acid, peroxide, carbonyl, and iodine values), color tone, and fatty acid composition were also measured.
Polar polymerized material content was found to increase linearly with time and constituted the major thermally oxidation products. Thus, both polymerized products and polar material possibly prove quite useful for assessing deterioration of heated oils. However, parameters such as carbonyl and acid values also increased with heating.
The main components in polymerization products from heat oils were found to be dimers. Most of the polymers were polar and there was thus a fairly good correlation between polymer and polar material content with a correlation coefficient larger than 0.95. Oil deterioration progressed much more rapidly during pan-frying than deepfat frying.

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Autoxidation of 1-isopropylazulene at 115±5°C in DMF or HMPA yielded 9 separable products. Each was a substitution product of an extra formyl group and its oxidation gave either a dimeric or trimeric product containing an extranuclear carbon unit and azulenylbenzofulvenes. Their structures were established or presumed on the basis of spectroscopic (NMR, UV, IR, and MS) data.
Possible reaction pathways are suggested for the formation of such a wide variety of interesting products.

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The antioxidative activity of α-tocotrienol (α-Toc 3) and its derivative was studied in the 2, 2'-azobis (2-amidinopropane) dihydrochloride (AAPH) initiated oxidation of dilinoleoylphosphatidylcholine (DLPC) lipo-somes. Two DLPC concentrations, 1.93×10-3M for total aqueous dispersion (condition-I) and around 0.3×10-3M for total aqueous dispersion (condition-II), were used, keeping the molar concentrations of antioxidants or initiator for DLPC constant. A kinetic study indicated that in DLPC bilayers, α-Toc 3 had the same anti-oxidative activity as α-tocopherol (α-Toc) at both concentrations. However, α-Toc 3 showed higher antioxidative activity than α-Toc when was added after liposome formation. The synthesized water-soluble derivative of α-Toc 3 added after DLPC liposome formation under condition-II, as well as water-soluble carboxy-2, 5, 7, 8-tetramethyl-6-chromanol, showed about the same antioxidative activity as α-Toc 3 mixed with DLPC prior to liposome formation under condition-II. Solubility in water was a factor determining the antioxidative activity of the water-soluble antioxidant under condition-II. It would thus appear that α-Toc3 shows higher antioxidative activity than α-Toc in vitro in the synthetic liposome system, and that this can be explained on the basis of the distribution of α-Toc 3 in, or in the vicinity of the DLPC bilayers.

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The effects of carotenoids on the oxidation of refined edible oils, especially the prooxidant effect, were examined. To study the roles of carotenoids in the oxidation of oils, , β-carotene (β-car) and its decomposition or oxidation products were added to test oils [methyl linoleate, soybean triglyceride or refined rapeseed oil] and allowed to oxidize with exposure to light or darkness. In the autoxidation of test oils with β-car the prooxidant effect of, β-car, was frequently observed, especially when the test oils were highly oxidized before the addition of β-car. The addition of, β-car usually improved the stability of test oils against photooxidation. The prooxidant effect of β-car was considered to arise not from β-car itself or the highly oxidized decomposition products of β-car, but rather from intermediate compounds during its oxidation. These compounds function as initiators for chain reactions of lipid oxidation. However, carotenoids may possibly not exert marked prooxidant effect on ordinary edible plant oils since considerably greater amounts of tocopherols than carotenoids are pre-sent and tocopherols have strong antioxidant effect on edible oils and residual carotenoids.

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Four kinds of chitin derivatives, 6-O (2-hydroxyethyl) chitin, 6-O- [2- (2-hydroxyethoxy) ethyl] chitin, 6-O- (2, 3-dihydroxypropyl) chitin and 6-O- (carboxymethyl) chitin, eight kinds of monocarboxylated chitosan derivatives, N- (carboxymethoxyacetyl) chitosan, N- (3-carboxy-propanoyl) chitosan, N- (3-carboxypropanoyl) chitosan, N- (carboxymethyl) chitosan, 6-O- (carboxymethyl) chitosan, N- (carboxymethoxyacetyl) -6-O- (2-hydroxyethyl) chitosan, N- (3-carboxypropanoyl) chitosan and N- (carboxymethyl) -6-O- (2-hydroxyethyl) chitosan, and two kinds of dicarboxylated chitosan derivatives, N- (carboxymethoxyacetyl) -6-O- (carboxy-methyl) chitosan and N- (2-carboxypropanoyl) -6-O- (carboxymethyl) chitosan were prepared and their moisture-absorption and moisture-release properties were examined and compared with those of hyaluronic acid.
The moisture-absorption and moisture release properties of 6-O- (carboxymethyl) chitosan, N- (carboxymethoxyacetyl) -6-O- (carboxymethyl) chitosan and N- (3-carboxypropanoyl) -6-O- (carboxymethyl) chitosan were found quite similar to those of hyaluronic acid. The introduction of carboxyl groups into chitin and chitosan improved their water retention capacity which was also considerably influenced by their positions of substituents and degree of substitution.

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The desorption rates of dodecyl sulfate ions from nylon particles in aqueous solutions were determined using newly developed apparatus in the electric conductivity stopped-flow method. The temperature dependence of the desorption rate in the early stage of process was investigated and the activation energy of desorption was calculated from Arrhenius plots of the experimental results as 65.5kJ/mol. This value was almost equal to the enthalpy of adsorption that was pre-viously estimated in the same system. It shows that there is no activation energy of adsorption in the early stage of the process.

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The structural characteristics of a water molecule on the membrane properties of L-α-phosphatidylcholines of different chain lengths were investigated by a differential scanning calorimeter (DSC) and small angle X-ray scattering machine (SAXS). Ten water molecules per L-α-phosphatidylcholine were interposed between the bilayers of lipid molecules in the coagel phase and were independent of n-alkyl chain length. On adding urea to L-α-phosphatid-ylcholine-water systems, some of the interlamella water was converted to free water, and the apparent amount of interlamella water decreased with urea content. Furthermore, urea had effect only on the coagel-to-gel transition (Tgel), and not the gel-to-lamella liquid crystalline transition (Tc).
The thickness of L-α-phosphatidylcholine (d1-dw) and interlamella distance (dw) of-L-α-phospatidylcholine bilayer decreased with increase in water and urea content. The radial distribution functions showed some lamella structural periodisity, which lessened on increasing water and urea content. It is thus evident that the structural characteristics of water molecules significantly determine the properties of the L-α-phosphatidylcholine bilayer.

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