Marine toxins occurring in lipid fractions are responsible for three types of seafood poisoning : diarrhetic shellfish poisoning (DSP), neurotoxic shellfish poisoning (NSP), and ciguatera fish poisoning. The major toxins in DSP, okadaic acid and its derivatives, originate from the dinoflagellates Dinophysis spp. The toxins inhibit protein phosphatase 2 A and are potent tumor promotors. Brevetoxins implicated in NSP are produced by the dinoflagellate Gymnodinium breve. The toxins are characterized by contiguous ether rings arranged in a laddershape. Ciguatoxins responsible for ciguatera originating from the dinoflagellate Gambierdiscus toxicus are also bear a ladder-shaped cyclic ether skeleton. Both brevetoxins and ciguatoxins potentiate voltage gated Na channels. All these toxins are highly oxygenated, extremely toxic, and possess high molecular weights. Chemical and biochemical methods for determining the toxins are described.

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Glycolipid GM3 increases with cell density of cell growth. GM3 of the plasma membrane is an important modulator of cellular functions of growth. Partial turnover of GM3 is regulated by the presence of the terminal sialic acid moiety. The activities of GM3-metabolizing enzymes i.e. sialidase or sialyltransferase change in the dividing cells. Both enzymes function in the growth control of cells with GM3-mediated inhibition of epidermal growth factor receptor phosphorylation. 2-Deoxy-2, 3-dehydro-N-acetylneuraminic acid (NeuAc2en) is a potent GM3 sialidase inhibitor, which resultantly shows the cell-growth inhibitory effect. Rational, computer-assisted drug design of NeuAc2en derivatives (strong inhibitors) was applied in the development of a new therapeutic treatment for influenza virus infection. CMP-NeuAc is known to produce NeuAc2en spontaneously in the physiological condition. Resultant NeuAc2en might regulate cellular sialidase activity. To further clarify cellular functions of GM3 sialidase or sialyltransferase, it is necessary to design new type of NeuAc2en or CMP-NeuAc derivatives, targeted on the subcellular site of the enzymes.

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Apoptosis is a mechanism for eliminating unwanted cells from the cell community in multicelluler organisms. Abnormalities in the regulation of apoptosis may play a part in the etiology of cancer, autoimmune diseases, AIDS and degenerative nerve diseases. About one-half neuronal cells undergo apoptosis during embryogenesis. Developing neurons compete for the specific tropic factors that support neuronal growth and differentiation by suppressing the pathway of apoptosis. However, the question of which molecules function as survival and maintenance factors for neurons remains open. Neurons are known to be highly enriched in lipids long-chain unsaturated fatty acids, especially docosahexaenoic acid (DHA). We examined here the effect of DHA on neuronal survival in cultured B50 cells, which are differentiated to neuronal cells by dibutyryl-cyclic AMP treatment. The results indicate that DHA acts as a survival/maintenance factor for neurons.

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The signaling roles of ceramide and sphingosine produced through the degrading processes of membrane sphingolipids are receiving hot attention in the recent biochemical and biomedical research fields. For these 9 years at the Biomembrane Institute (director, Prof. S. Hakomori), Seattle, we have studied functional roles of various sphingolipids such as ceramide, sphingosine, methylsphingosines, and sphingosine 1-phosphate in a variety of biomedical systems. First, the recent conceptual development on sphingolipid signaling pathways is outlined and critically analyzed. Next, our studies and findings on the involvement of sphingosine in apoptosis induction of neutrophils and leukemic HL-60 cells are described. Based upon these studies, the perspective of future sphingosine research (sphingology) with an eye towards the 21 st century is briefly mentioned.

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The functional studies of glycosphingolipids in hematology and immunology fields have been discussed in this review. First, (1) Glycolipid antigens known as cell surface differentiation antigens of human leukocytes, (2) glycosphingolipids that determine the differentiation direction of human myelogenous leukemia cell line HL-60 cells, (3) their expression control mechanism, and (4) the control mechanism of cell differentiation by the glycolipids are summarized. Subsequently, (5) sugar chain expression control mechanism of selectin ligands in human B lymphoid cell lines, (6) cytokine (IL-3) -associated and autonomous growth-associated ganglioside GD1a in mouse myelogenousleukemia cell line NFS60 cells, (7) its expression mechanism, and (8) its transcription and cell growth control mechanism through STATS are described.

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The studies of analysis of triacylglycerol (TG) compositions were reviewed and the oxidation method was illustrated to determine TG compositions sensitively by inexpensive TLC-FID apparatus. The data analysis in this method are very simple, since numerous TG species are summarized four TG compositions, S₃, S₂U, SU₂ and U₃. Therefore, edible fats of any physical properties may be easily prepared based on the TG compositions. Further, TG species of plastic fats determined by the combined use of TLC-FID and GLC are nearly equal to those by high resolution HPLC or GLC.

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Biomedical modulation effect on lipid compounds such as phytosterol (sitosterol), γ-oryzanol (β-sitosterol ferulic acid ester), sitostanol fatty acid ester, phosphatidylcholine, sn-1-oleoyl-sn-2-docosahexaenoyl phosphatidylcholine and primary fatty acid amid reviwed.
Phytosterol, γ-oryzanol and sitostanol fatty acid ester improved serum lipid metabolism. Especially, γ-oryzanol has a good effect on central nervous system.
Lipid compounds, phosphatidylcholine, sn-1-oleoyl-sn-2-docosahexaenoyl phosphatidylcholine and primary fatty acid amid induced natural REM sleep.

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Maillard reaction is one of the most important reactions in chemical changes of food components during storage and processing of foods. The reaction is known to proceed nonenzymatically, progressing also in vivo as well as soil. The Maillard reaction can be classified by mechanisms involving oxidative and non-oxidative reactions. The oxidative reaction leads to the generation of advanced glycation end products (AGEs) via precursors by the autoxidation of glucose and subsequent glycoxidation with the formation of active oxygen species. Deoxyosones such as 3-deoxyglucosone (3DG) are thought to be formed by the non-oxidative reaction followed by the formation of AGEs.On the other hand, melanoidins, one of AGEs, have a strong scavenging activity against active oxygen species, e.g. hydroxyl radicals, hydrogen peroxides and superoxides. The scavenging of active oxygen species by melanoidins seems to be significant for explanation of the appearance of the antioxidative and desmutagenic activities.

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To investigate the deterioration of fats and oils by hot plate heating, several experiments were carrid out. Lard (2g, 10g) and /or vegetable oils (2g, 10g) kept in beaker (500mL) were heated using hot plate for 10min at 200°C. Lard and vegetable oils with or without silicone oil (5 ppm) were also heated using the same way. The effect of some antioxidants such as tocopherol, silicone oil and lecithin on the thermal deterioration was compared. To prevent the deterioration of lard during heating, adding a mixture of tocopherol (0.1%), soybean lecithin (0.5%) and silicone oil (5ppm) showed better effect than adding them separately. Addition of silicone oil (5ppm) alone could supperss the deterioration of fats and oils by heating, residual tocopherol increased. Silicone oil effectively suppress the thermal deterioration, but no such effect was noticed on autoxidation of oils. Commercially available cooking oils with lecithin showed preventive effect on deterioration of oils by heating. The degree of thermal decomposition of tocopherol in heated oils at 200°C was found to much more high levels of oleic acid in sufflower oil (HOSO) than high levels of linoleic acid in safflower oil (HLSO). Deterioration of oils was affected remarkably to the specific surface area and heating temperature.

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Lipid peroxidation mediated by free radicals is believed to be one of the important causes of membrane and cell damage. So the measurement of lipid peroxide is useful to know the mechanism of oxidation in various diseases. For example, we have been investigated that the lipid peroxide caused by the stress in gastric mucosa is suggested to cause gastric lesions. The same findings are seen in other diseases like as diabetes mellitus, liver diseases, and so on. The analysis of lipidperoxide is usually done by thiobarbituric acid (TBA) or MCDP method clinically. We have also established the analytic system of lipid hydroperoxide by high performance liquid chromatography (HPLC) using chemiluminescense which could separate unsaturated fatty acid and lipid hydroperoxide simultaneously. The water immersion restraint stress of rat induced significant rise of anti-oxidant capability as an adaptive reaction. So the measurement of anti-oxidant capability is also an important way to know the pathophysiology of diseases induced by oxidant stress.

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With increasing evidence which shows the involvement of oxygen radicals in a variety of pathological events, cancer and aging, the role of antioxidants has received much attention. In order to develop a novel potent radical-scavenging antioxidant, the ideal structure of phenolic compound was designed considering the factors that determine antioxidant potency. 2, 3-Dihydro-5-hydroxy-2, 2-dipentyl-4, 6-di-t-butylbenzofuran (BO-653) was thus synthesized and its antioxidant activity was evaluated against lipid peroxidations in vitro. The electron spin resonance study showed that the phenoxyl radical derived from BO-653 was more resonance-stabilized than α-tocopheroxyl radical and BO-653 reduced α-tocopheroxyl radical rapidly. Although the chemical reactivity of BO-653 toward peroxyl radical was smaller than that of α-tocopherol, its antioxidant potency against lipid peroxidation in phosphatidylcholine liposomal membranes an low density lipoprotein (LDL) was superior to that of α-tocopherol. Ascorbic acid reduced the phenoxyl radical derived from BO-653 in the homogeneous solution, but it did not spare BO-653 in the oxidation of liposomal membranes or LDL. It was concluded that BO-653 is a potent novel radical-scavenging antioxidant.

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Microbial transformation of various monoterpenoids was reviewed. Developmental studies on application of plant parasitic fungus as biocatalysis, techniques for selective transformation and better yields of desired products are highlighted. The reaction types and stereochemistry in the biotransformation are described in 97 monoterpenoids. Various monoterpenoid substrates, their metabilities and the micro-organisms used for the transformations are compiled covering the literature for the period late 1980-1997.

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The mortality of heart disease in Japan remains very low compared with that in the United States, France and the United Kingdom.
Genetic factors presumably play a large part in this difference but lifestyle, together with recent efforts in understanding dietary contributions through clinical nutrition research also plays an important role.
Many studies have confirmed that while saturated fatty acids increase serum cholesterol levels, polyunsaturated fatty acids, especially n-6 fatty acids decrease serum cholesterol levels.
However, the biological down-side of increasing n-6 fatty acid levels is an increase in sus-ceptibility of LDL to oxidation : when associated with oxidative changes to PUFA-rich LDL, the result is that an increased atherogenesity of this lipoprotein intake is an increased susceptibility of LDL to oxidation.
With this in mind, an analysis of the current Japanese fat intake suggests that the present levels of consumption regarding both quantity and quality of fat are ideal for preventing the current low levels of atherosclerosis in this country.

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Bacteria in the large intestine produce short-chain fatty acids such as acetic, propionic and butyric acids. Major factors that influence the production of these acids are composition and entry rate of substrates, and transit time in the proximal large intestine. Short-chain fatty acids are major energy substrate for colonocytes and contribute to systemic energy budget. Short-chain fatty acids affects water/solute absorption and mucosal blood flow in the large intestine, intestinal epithelial proliferation, intestinal motility and pancreatic exocrine secretion. Such effects often involves local transmission mechanism and sometimes systemic mediatory mechanism such as autonomic nerve system.

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Glucosylceramide (cerebroside), the representative plant sphingolipid, has been reported to be located in plasma membranes and tonoplasts as a mojor lipid class. In general, sphingolipids are known to possess the function which is structural and providing increased rigidity to membranes, but the high proportions of cerebroside in plant membranes might effect negatively on the regulation of fluidity and induce the local gel-to-liquid crystalline phase transition under the low temperature condition. Intensive research, therefore, has focussed upon the roles of the plant sphingolipids in relation to chilling- (and/or freezing-) injury.
In this review, we describe structural information on plant sphingolipids, which is quite different with that of animal sphingolipids, including molecular species diversity of cerebrosides separated from chilling-sensitive and chilling-resistant plants, thermotrophic properties of corebroside species determined using DSC, and prominent changes in the cerebroside composition as the response to the low temperature stress. Our recent studies on metabolism of plant sphingolipids are also presented.

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Studies on liquefaction of biomass in the presence of phenols or alcohols with or without acid catalyst has been developing. Successive liquefaction apparatuses have been developed very recently. By using these apparatus, wood can be liquefied within five to fifteen min. The liquefied wooden products can be converted easily to adhesives, three-dimensionally cured molded materials, foams, carbon fibers and others. Even injection molding is adoptable. Most of these molded materials have been proved to be biodegradable. On the other hand, after analyses of these liquefaction products it has been found that the liquefactions without catalyst at an elevated temperature of 250°C proceed mainly through homolysis, while in the presence of strong acids and under the temperature of 150°C the reactions proceed through heterolytic solvolysis.

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Dietary lipid is received by mucosal cells in the gastrointestinal tract before absorption from the small intestine, and the lipid enhances the secretion of various gut hormones, cholecystokinin, secretin, entroglucagon, PYY and glucose-dependent insulinotropic peptide, and stimulates enteric nervous system. Gut hormones and the nervous systems are interact each other and regulate gastrointestinal functions, exocrine secretion, gastric acid secretion, gastric emptying and mucosal growth of the small intestine. Also, properties of dietary fat, especially content of n-3 and n-6 fatty acids, influence colonic mucosal growth through production of icosanoids by mucosal cells. These are involved in inflammatory bowel disease and colon cancer.

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Many kinds of effective compounds are contained in vegetables. Particularly, lipid is a necessary substance for plants and animals to keep in satisfactory condition to sustain their lives. In general, plants biosynthesize many kinds of effective fatty acids and sterols as lipid, compared with animals. This paper can be summarized as follows ; (1) The content of palmitic acid, linolic acid, sitosterol, campesterol and cholesterol in seed oils of cacti are correlated with evolution of cacti. Especially, it was detected that the content of cholesterol in Cactoideae is less than that of Opuntioideae. (2) Two unusual fatty acids ; cis-9, trans-11, trans-13, cis-15-octadecatetraenoic acid (α-parinaric acid) and cis-9, trans-14, octadecadien-, 12-ynoic acid (dehydrocrepenic acid) were detected in the fatty acid components of C. cristata. In the seeds of I. balsamina large amount of α-parinaric acid is contained. It is the first discovery of α-parinaric acid detected from fungi. While dehydrocrepenic acid is contained in Clavulinaceae and Cantharellaceae, it is not contained in Ramariaceae and Gomphaceae. In addition, brassicasterol was detected in common as a sterol component of Ascomycetes. In general, Brassicaceae contains a large amount of brassicasterol, it was not detected in fungi. It is the first discovery ofbrassicasterol detected from fungi. These results suggest that dehydrocrepenic acid and brassica-sterol are applied for classification of fungi because their forms are similar to each other. (3) The seed oils detected from Lamiaceae contains a large amount of α-linolenic acid. For example P. frutescens oil contains it about 60%, and O. basilicum oil about 50%. This result suggests that the seeds of Lamiaceae are expected to be used as a souce of α-linolenic acid.

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In the tropics, the fruit of coconut palm is the most useful fruit. Coconut oil is produced from endosperm of the fruit and the production is a large quantities in Southeast Asia. 61% of the world production in 1996 was produced in Philippines and Indonesia and 87% of the world export in 1996 were exported from these countries. Also, the production capacity of alcohol from coconut oil is 99 thousand tons per annum in Philippines. A factory is using 60 thousand tons of coconut oil per annum for oleochemicals in Indonesia.
The future aspects of coconut oil about the increased yield through the plantation of the recommended hybrids, the development of wet method on oil separation process and the multiple utilization of the whole coconut fruit are described.

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Recently some books about “A FOOD CRISIS” are published. How about recent situation of edible oils and fats ? We can't say anything about recent situation of edible oils and fats without situation of China and palm oil. The world market of oils and fats is affected by purchase from China very much and price level was moved to higher level when China purchased big volume of palm oil.
World consumption of oils and fats has been increasing and much quantity of oils and fats will be required in the future. Conversely harvested area can't be increased so much.
If we want to achieve production which satisfy consumption of all people in the world, biotechnology is indispensable in order to enable oilseeds with higher yield.

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Recent studies on the polyunsaturated fatty acid (PUFA) production by microorganisms and unicellular algae are reviewed. Lately, microbial lipid production, especially production of PUFA, difficult to obtain from plant or animal oils, has attracted general interest. However, not many researches on lipid production by microorganisms have been carried out. Industrial production of γ-linolenic acid from the Mortierella was already begun in Japan, as the first industrial application of “Single Cell Oil”. Production of arachidonic acid and the other C₂₀- PUFAs were reported using Mortierella alpina and its mutants. Microbial production of docosahexaenoic acid (DHA) has been found in, Labyrinthulea, unicellular algae, and bacteria of marine origin, their growth rate or productivity were generally low. We isolated a new strain of marine fungi, Schizochytrium sp. that contained high levels of DHA and n-6 docosapentaenoic acid. High DHA productivity was due to high growth rate, and high lipid content of the strain. This strain is a promising resource for microbial DHA production as well as study on PUFA syntheses.

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Gene transformation technology has been developed to increase food production and improve food quality as one of the most important tools to overcome the future food dificiency in the world. The first group of transgenic oil seed crops is for agronomic improvement. The second group is for the changes in fatty acids in oil seed crops to meet with the consumer's needs and/or oil processors' needs. In the first group, there are herbicide tolerant crops and insect resistant crops today. In the second group, high laurate canola is the only one example at this moment, but many research works have been being made in this area. It is expected that some of the improved oil seed crops are in the market around 2000. This paper also covers food safetyof transgenic crops with RoundupReady® soybean as an example.

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The Recombinant DNA (rDNA) technique is expected to bring about a great progress in the improvement of breeding technology and the development of new plant varieties showing high quality and high yield, such as those with excellent pest and disease resistances, those with environmental stress tolerance, etc. In the USA, a late ripening tomato variety which was developed through the rDNA technology was commercialized as the world's first recombinant food in 1994. Seven transgenic crop plants, such as herbicide tolerant soybean and canola, insect resistant corn and potato, were complied the all safety assessments with the guidelines required and they are marketable in Japan.
General public, however, are not familiar with rDNA technology, and some seem to feel uncomfortable with biotechnology. It is caused by the difficulty of the technology, and lacking of sufficient information. In order to promote agricultural biotechnology, it is important to give precise information about rDNA technology to general public so that they can comfortably accept the products. Because, the rDNA technique is the most important technology to improve world's food supply and global environment in the next century.

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Fat replacers consist of carbohydrate-based fat mimetics, protein-based fat mimetics, structured lipids and synthesized fat mimetics. Carbohydrate-based and protein-based fat mimetics are now used in many kinds of products prepared under low or room temperature. These fat mimetics can decrease calorie levels of products when compared to products containing regular fat, because these fat mimetics have only 4 kcal/g compared to 9 kcal/g in regular fat. However, these fat mimetics can not be used in fried foods and chocolates. On the other hand, structured lipids and synthesized fat mimetics are used in chocolates, baked products and snacks. Synthesized fat mimetics do not have fat structures and are hard to be digested in the small intestine. As a result, these mimetics become 0 or almost 0 kcal/g. Products using structured lipids are already available on the Japanese market, but synthesized fat mimetics are not allowed in Japan yet.

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