Adipose tissue is a source of passively stored excess energy. Adipose tissue has been found to secrete various biologically active adipocytokines such as leptin, plasminogen activator inhibitor (PAI) -1 and tumor necrosis factor (TNF) α, which affect homeostasis throughout the body. Plasma adipocytokines increase in obesity and the accumulation of fat, especially visceral fat, may serve to create greater insulin resistance or thrombotic tendency in obesity, through enhanced secretion of the above compounds.
In search for genes expressed in adipose tissue, novel adipose-specific genes, adiponectin and aquaporin adipose were isolated in the present study. Adiponectin had a collagen-like sequence and was secreted into blood. Plasma adiponectin paradoxically decreased in obesity, but was expressed exclusively in adipose tissue. Aquaporin adipose is also highly expressed in adipose tissue. This new water channel transports glycerol as well as water, suggesting aquaporin adipose to possibly be essential to glycerol metabolism in adipocytes.
The finding of genes specifically expressed in visceral fat and new adipocytokines should facilitate clarification of the mechanism for the development and complications of visceral fat accumulation.

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The nutritive values of fats and oils have been usually discussed on their fatty acid composition. However, the arrangement of fatty acids on the glycerol backbone of triacylglycerols of natural fats have been indicated to be responsible for not only absorbability of fatty acids but also specific effects on lipid metabolism. The structured lipids which have been restructured to change position of fatty acids and modified to change fatty acid composition from native state have been developed to deliver specific fatty acids that can ameliorate some of disease states. The typical structured lipids are triacylglycerols containing mixtures of medium chain and long chain fatty acids in the same glycerol molecule in order to exhibit their maximum potency.

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Conjugated linoleic acid is a mixture of geometrical and positional isomers of linoleic acid. Extensive animal studies indicate conjugated linoleic acid to function as powerful anticarcinogen. Conjugated linoleic acid has antiatherogenic, antidiabetic and antiallergic potential, reduces body fat and influences bone formation. Conjugated linoleic acid may be obtained from linoleic acid by bacterial interactions in the rumen. Meat and dairy products from ruminant animals contain 2-5mg conjugated linoleic acid per g fat. No toxicity of conjugated linoleic acid has been reported in animal feeding studies. Although more information on toxicity in humans should be made available, conjugated linoleic acid ought to be usable as a component of functional foods.Key words : conjugated linoleic acid, anticarcinogen, functional foods.

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In fat cells there are lipogenic and lipolytic pathways. In the lipogenic pathway, blood glucose is incorporated into fat cells by insulin and converted to triglyceride through α-glycerophosphate and citrate. Human fat cells contain ATP-citrate lyase which changes citrate to acetylcoA and oxaloacetic acid. The triglyceride portion of chylomicron or VLDL is hydrolyzed by lipoprotein lipase to glycerol and fatty acids which are then incorporated into fat cells and converted to triglyceride with α-glycerophosphate derived from glucose. Triglyceride thus synthesized in fat cells, has the form of lipid droplets whose surface are covered with phospholipids including lecithin and proteins.
Lipolysis induced by catecholamines and ACTH may possibly be mediated by the cyclic AMP cascade. Lipolytic hormones activate adenylate cyclase, to increase cyclic AMP formation. Cyclic AMP promotes lipolytic activity by elevating cyclic AMP-dependent protein kinase activity which in turn activates hormone-sensitive lipase (HSL) through phosphorylation, resulting in the hydrolysis of stored triglyceride to glycerol and free fatty acids. However, this theory is attended with some problems. For instance, it was found that norepinephrine induced lipolysis in fat cells without a concomitant increase in HSL activity. Neither ACTH-induced lipolysis in fat cells nor its inhibition by insulin was accompanied by matching fluctuations in HSL activity. Thus, another mechanism of lipolysis than the cyclic AMP cascade is proposed.

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The adjustment function of human's energy metabolizing has been examined and it has been clarified that this adjustment function disorder exist in the obesity person. Especially, an essential decrease of diet induced thermogenesis (DIT) and resting metabolic rate (RMR) has been seen by the obesity person and the gap of the setpoint of the energy metabolizing has been thought as cause of obesity. And also meal and the nutrient take part in such an energy metabolicdisorder have been examined. It has been understood that an excessive intake of fat, undernourished of the breakfast and excessive intake of supper and the midnight snack promote the body fat.

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Dietary fats and oils are essential for maintaining health. The chemical characteristics and physiological effects of fats and oils differ. And the various fatty acids present in fats and oils have different functions in human nutrition, and thus a well-balanced intake is desirable. Not only the quantity of fat but also the quality of fat or fatty acids are recommended for maintaining good health in the Recommended Dietary Allowances for Japanese.
In 1946 daily average intake of dietary fat by Japanese was 14.7g, and fat energy ratio was 7.0%. By 1997, the intake of fat had increased to 59.3g, with cooking fats and oils accounting for 17.0g. The increase in fat intake was due not only to vegetable oil consumption but much more so to a marked increase in dietary animal fat.
Yearly changes in fatty acid intake from 1952 through 1997 by Japanese were determined based on the National Nutrition Survey. The n-6/n-3 and other fatty acid intake data were calculated.
The relation between colon and breast cancer mortality and dietary fatty acid intake was discussed. A significant increase in mortality was found with increased fat intake, and it is suggested that as a preventive measure fat intake should not exceed designated levels.

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Fish oil is rich in n-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA) and cicosapentaenoic acid (EPA). These fatty acids are generally recognized as biologically important lipids that play a significant role in protecting against cardiovascular disease, cancer, and inflammation. Moreover, many studies demonstrate that intake of fish oil, especially DHA, influences brain development, learning and memory, and visual function. Recently, the preventative and remedial effects of DHA oil on dementia and mental disorders have been reported. In this review, the health benefits of fish oil are summarized, and new data on the effects of DHA oil on intelligence score and visual acuity in the elderly are presented.

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Breast milk is the best source of nutrition for infant growth and development. Breast feeding an infant is not always possible because have insufficient in quantity of breast milk or social conditions. In such a case, infant formula sufficient for growth and development must be used. Large amounts of polyunsaturated fatty acids (PUFA), i.e., linoleic acid, arachidonic acid, alfa-liolenic acid, eicosapentaenoic acid and docosahexaenoic acid (DHA) are present in breast milk. Infant formula well-balanced in essential fatty acids was produced subsequent to demonstrating the need for alfa-liolenic acid.
DHA-fortified infant formula was recently been developed to provide DHA equivalent to that in Japanese human milk, because DHA is essential to development of the neonatal brain and retina. Visual acuity and/or visual evoked potential assessed the significance of PUFA for term infants. The results were compared with the learning ability of rats.

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Neuronal dysfunction with aging is thought to stem from impaired synaptic functions. Brain function impairment is reflected by memory loss with synaptic reduced transmission as the underlying mechanism. Synaptic hypofunction in relation to lipids may be explained by age-related alterations in the lipid composition and physical properties of synaptic plasma membranes. Cholesterol/phospholipid (C/P) ratio and lipid asymmetry in membranes are supposed to play important roles in the regulation of receptor function and subsequent signaling.
The effects of dietary lipids on synaptic and neural functions are discussed in terms of lipid nutrition, with attention to lipid quantities and quality, and the physiological effects of saturated and polyunsaturated fatty acids, especially of n-6 and n-3 series. Those in some cases are interpreted by molecular mechanisms considered applicable. Pharmacological approaches using complex lipids to neural pathology such as Alzheimer's and Parkinson's diseases are briefly presented.

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Lignans arc one of the major phytochemicals which have many biological activity.In sesame seeds, unique lipid-soluble antioxidative lignans such as sesamolin, pinoresinol and sesaminol together with two major lignans (sesamin and sesamolin). Recently, functional activities of these lignans have been extensively examined and found to exhibit many type of biological activities. Addition of these lipid-soluble lignans, novel type of water-soluble lignan glucosides were also found in defatted sesame seeds, and sesaminol can be produced both during the purification process of sesame salad oil and also by the hydrolysis of sesaminol glucosides by intestinal bacteria. By using in vitro assay system, sesaminol was found to show the strong protective role from LDL oxidation induced by Cu ion and AMVN by evaluation using immunochemical methods. In order to evaluate the protection against atherosclerosis in vivo using rabbits, addition of 10% defatted sesame flour to 1% cholesterol diets protected the formation of atherosclerosis. Addition of 0.2% of the isolated sesaminolglucoside has also been found to significantly reduced the development of atherosclerosis in LDL receptor deficient rabbits (WHHL).

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About 200 natural substances are known to be phytoestrogens which are derived from plants with estrogenicity. Among them, isoflavones are the most potent, and coumestrol, genistein and daidzein show greater estrogenicity than other phytoestrogens. Estrogenicity of phytoestrogens is discussed in terms of endocrine disruption, since Japanese consume large quantities of phytoestrogens present in soy products, apparently having greater estrogenicity (in vitro assay) and daily intake as compared with general chemicals (such as Bisphenol A or 4-nonylphenol) frequently cited as estrogenic compounds. On the other hand, isoflavones are considered effective for preventing osteoporosis, breast cancer and prostate cancer and reducing blood cholesterol. The mode of action of phytoestrogens on the molecular level should be clarified so as to estimate risks and benefits of phytoestrogens.

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The antimutagenicity and anticarcinogenicity of terpenoids were examined in the present our study with attention to applications of the umu test for detecting antimutagenicity. Studies on antimutagenicity, anticarcinogenicity and mutagenicity of 87 terpenoids have appeared in the past 10 years. Various terpenoid substrates, mutagens, tests, antimutagenicity, anticarcinogenicity and mutagenicity in the literature from 19891999 are reviewed.

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The order of antioxidant activity of vitamin E homologues in vitro and in vivo has long been a matter under investigation. Examination of the metabolic fate of vitamin E has indicated that biodiscrimination caused by α-tocopherol transfer protein against non-α-tocopherols makes α-tocopherol vastly superior to other homologues. This has provided some clarification of the relative biopotency of vitamin E homologues in food chemistry.
Vitamin E exerts biological activity through interactions with various biological reducing agents. An antioxidant network in vivo including vitamin E should thus provide some indication of the source of synergists. Attention is presently being focused on how repair of the tocopheroxyl radical is a potent tool to find out excellent synergists in food chemistry.
Latest applications of vitamin E in food are discussed.

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Dietary carotenoids are absorbed from the digestive tract and distributed in tissues and fluids in the body. However, little is yet known on their physiological function, except for provitamin A activity. Antioxidant activity of carotenoids, including free radical scavenging and singlet oxygen quenching, has been well documented. Nevertheless, it is unclear whether or not this activity significantly contributes to the antioxidative defense system in vivo. Alternatively, the inhibition of cell proliferation and the induction of cell differentiation explain antitumorigenic effect of carotenoids in animal study. Enhancement of gap junctional communication may be also included in the effect of carotenoids. For the estimation of physiological function of dietary carotenoids, it is essential to understand their absorption and metabolism. 15, 15'-Dioxygenase activity responsible for vitamin A activity is widely distributed in tissues and the absorption of carotenoids from digestive tract is significantly affected by diet factors. Finally their metabolic pathway is obscure although oxidative process is recently suggested.

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Many foods, such as red wine, contain trace amounts of proanthocyanidins that are polyphenols, whose functions are little understood. Antioxidative and related functions and disease preventive action were examined. Uses, methods of manufacture and products of grape seed extract comprising proanthocyanidins as principle components are discussed in detail.

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Recent development in edible oils and fat analysis for determining of composition of what and characterization are presented.
A method for analyzing the trans fatty acids in for oils and fats by infrared spectroscopy (IR) and gas liquid chromatography (GLC) was established along with practical method for determining triacylglycerol composition and stereospecific data by high performance liquid chromatography (HPLC). Presently available method for estimating sterol, iodine, acid, anisidine, color and food additives are discussed.

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Various steps in the processing of soybean and canola into finished oil and meal products are reviewed. The presence of nonhydratable phospholipids (NHP) in crude oil reduces the efficiency of degumming and makes necessary additional acid treatment, with consequent loss of neutral oil. Recent heat treatment of seeds or flakes before extraction using ALCON, Expander or Super Expro is explained in detail.
Enzymatic degumming and spent clay disposal are briefly explained.
Topics on flavor reversion of edible soybean oil are introduced.

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Facilities and operation conditions of the deodorization process were reviewed. Quality of edible oil products depends on choice of the deodorization condition, therefore the effects of the deodorization condition on quality of refined oils were also described.
In proportion as consumer's favors on edible oils diversified, differentiated products to meet the demand for nutritional values, special taste and flavor, or for minimizing odor and dirt in kitchens, have increased in number in the edible oil market. Assessment of polymerized materials and odor for quality evaluation of edible oils was discussed.

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Major flavor components in edible fats and oils are aldehyde, ketone, alcohol, acid, and hydrocarbon produced from fatty acid hydroperoxides. Sulfur-and nitrogen-containing compounds are potent flavor components in sesame and olive oils. Gas liquid chromatography is quite useful, although sensory evaluation, colorimetry, odor sensor and chromatography may also be used for analytical methods of flavor components. Temperature, oxygen, moisture, light, acidic compounds and mionor components such as antioxidant, photosensitizer and metals can affect the production of flavor components in edible fats and oils as well as fatty acid composition.

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The hydrogenation of edible oil is a basic means for converting liquid oils into plastic fats at oil and fat companies.
Fundamental hydrogenation and current continuous reactor using a fixed-bed catalyst and supercritical process are discussed. New types of nickel and precious metal catalysts and current developments in reactors are presented.

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Interesterification is a fundamental modification widely used in the fats and oils industry on a commercial scale. This process involves rearrangement of fatty acid chains within and between triacylglycerol molecules, with consequent improvement of the physical properties of fats and oils.
A recently, developed enzymatic process makes possible regiospecific reactions. This paper outlines interesterification and introduces future applications.

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Soybean lecithin, the most important surface active agent in food systems and industrial use, is derived from soybean through the extraction of crude oil, hydration of crude oil, separation of wet gum and drying. The problems in obteining high quality lecithin are discussed and a new processing procedure of fluid lecithin by direct filtration of crude lecithin is presented. The processing of newly developed and commercialized lecithin, oil-free lecithin, fractionated lecithin, enzymatically decomposed lecithin and chemically modified lecithin including hydrogenated and hydroxylated lecithin is also discussed, along with the characteristics of each lecithin. By the new processing procedure, lecithin with good physiological function should find more uses not only in food, but cosmetic, pharmaceutical and medicinal feilds as well.

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Docosahexaenoic acid ethyl ester (DHA-E) could be refined by a pilot-scale Supercritical Fluid Chromatography (SFC) using silver-loaded spherical clay material [SC (Ag)] in a new chromatographic stationary phase. High purity DHA-E (99%) could thus be recovered to a greater degree by using the fish 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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Emulsification techniques, that involve active agents, are widely in use today. Emulsification techniques for milk and milk products, as well as new emulsification methods such as membrane emulsification system, high pressure emulsification system and highly purified polyglycerol fatty acid ester are discussed.
The agglomeration of fat globules is promoted during whipping and freezing in cream and ice cream. To create fat globule structure and maintain stability of air cells, production conditions which control the rate of fat globule agglomeration are essential.
The new technique for membrane emulsification, allows control of dispersed droplet size. And uniform dispersed emulsion size is possible. High pressure emulsification runs continuously and require efficient, stable emulsification. Using a highly purified polyglycerol fatty acid ester, oil soluble flavor substances color and vitamins can be made transparent.

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Recent progress in the crystallization of fats, particularly cocoa butter and related triacylglycerols (TAGs) is reviewed. Polymorphism of POP, POS and SOS is compared with that of cocoa butter and polymorphic transformation in tempering in chocolate manufacturing is discussed based on the results of crystallization kinetics obtained by pure TAGs. In place of tempering, a newly developed seeding technique, using BOB (β₂) crystal powder and a method for preventing fat blooming at high temperature are discussed. Intermolecular compounds made with SOS and OSO in equal weight were applied to cocoa butter, and unique physical properties of chocolate involving OSO are discussed.

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