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Japanese people consume crop bran, which contains relatively high amounts of gamma-oryzanol (ORZ), as foodstuffs and food materials. We have recently confirmed that ORZ inhibits NF-κB activation, activates peroxisome proliferator-activated receptor gamma (PPARγ), and increases plasma adiponectin levels. ORZ is therefore expected to improve lipid and carbohydrate metabolisms and various inflammatory diseases, i.e., metabolic syndrome including type 2 diabetes. ORZ administration also allowed fish, such as rainbow trout, yellowtail, and red sea bream, to accumulate protein through enhancement of lipid and carbohydrate metabolisms. In the present study, we have investigated ORZ accumulation levels in mouse and rainbow trout administered ORZ-containing feed. Although mouse muscle and liver hardly contained ORZ, muscle tissues of every fish species accumulated higher amounts of ORZ. These findings suggest that rainbow trout, red sea bream, and yellowtail accumulate ORZ in muscle.

We developed a novel flow injection assay for cortisol based on competitive immunologic reactions, magnetic separation, and electrochemical measurement. The proposed flow assay system was composed ...

A novel immunologic method using antigen-antibody reactions and electrochemical measurement to monitor the oocyte maturation-inducing hormone 17, 20β-dihydroxy-4-pregnen-3-one (DHP) in fish was dev...

The oxidization of fatty acids generates many volatile compounds forming an aroma, but little is known whether mammals use gustatory sense to detect the oxidized products as a taste or only use olfactory sense to detect as an aroma. We examined in this study the effect of aqueous extracts of the compounds from autoxidized arachidonic acid (AA) ethyl ester or hexanal which is the predominant component generated from oxidized AA by the anosmic mouse licking performance to a tastant. The addition of the water extract from oxidized AA or hexanal to a quinine hydrochloride (QHCl) solution decreased the anosmic mice licking frequency at several concentrations of QHCl. Hexanal also reduced the licking frequency of anosmic mice conditioned to avoid MSG at several concentrations of monosodium glutamate (MSG). These results suggest that hexanal would affect mouse taste perception to QHCl and MSG via the gustatory sensation.

Replacement of fishmeal with plant ingredients will introduce not only plant oil and protein but also phytosterol to the fish diet. Mammals strictly restrict the uptake of phytosterol at intestinal epithelial cells by regulating the gene expressions of sterol uptake and excretion proteins; however, phytosterol is found in the fish muscle and other organs. In order to assess the ability of phytosterol uptake by the intestinal epithelial cells of fish, no-sterol diet, cholesterol-, and β-sitosterol-containing diet was separately administered to zebrafish, and the relative mRNA expressions related to sterol uptake and excretion were evaluated. Gene expression of Niemann-Pick C1-like protein 1 in the sitosterol-fed group was significantly higher than that of the cholesterol-fed group (p < 0.05). The expression of apolipoprotein A-I gene was also higher in the sitosterol-fed group than that in the no-sterol and cholesterol-fed groups. The expressions of ATP-binding cassette, sub-family G, member 5 and 8, were significantly higher in the sitosterol-fed group, compared to the no-sterol group. Regarding the gene expression of ATP-binding cassette sub-family A, member 1, the sitosterol-fed group showed higher expression level compared to the other groups (p < 0.01). These results suggest that fish should be tolerant to phytosterols in contrast to mammals.

The antimelanosic and antioxidative properties of a hot water extract prepared from the fruiting body of the edible mushroom (Flammulina velutipes) were evaluated by dietary supplementation in Kuruma shrimp (Marsupenaeus japonicus) for possible aquaculture application. The extract contained ergothioneine (ERT) at a level of 2.05 mg/mL. A commercial standard of l-ergothioneine (l-ERT) and the mushroom extract showed inhibitory activity against mushroom polyphenoloxidase (PPO). Feeding of the extract had no adverse effects on the immune systems of the shrimp under the present experimental conditions. Supplementation of the extract in the diet significantly suppressed PPO activities in the hemolymphs of the shrimp. Expression of the prophenoloxidase (proPO) gene decreased in the hemocyte of the Kuruma shrimp fed with the mushroom extract. Consequently, development of melanosis was significantly suppressed in the supplement fed shrimp during ice storage. Lipid oxidation was also effectively controlled in the supplement fed group throughout the storage period. In vitro experiments showed that l-ERT effectively inhibited the activation of proPO in the hemocyte lysate supernatant (HLS). The transcript of the proPO gene in the hemocyte showed lower expression in the l-ERT-treated HLS. It was concluded that dietary supplementation of the mushroom extract in shrimp could be a promising approach to control post mortem development of melanosis and lipid oxidation in shrimp muscles.

The ability of a hydrophilic extract prepared from edible mushroom (Flammulina velutipes) to stabilize fresh color of bigeye tuna (Thunnus obesus) meat was evaluated to compare it with certain other antioxidants. The fresh color shelf life of bigeye tuna meats, to which were added as 1, 3, or 5 mL of mushroom extract to 100 g of minced bigeye tuna meat, prolonged duration of ice storage by more than 2, 4, and 6 d, respectively, in comparison with the control tuna meat without mushroom extract. The addition of 5 mL of mushroom extract to 100 g of minced bigeye tuna meat was more effective than adding ascorbic acid sodium salt (500 ppm) or α-tocopherol (500 ppm) with regard to oxidation of lipid in the tuna meat. The color changes significantly correlated with lipid oxidation as well as metmyoglobin formation in the tuna meat. These results clearly show that the mushroom extract is a potential antioxidant, which has the ability to stabilize fresh color of tuna meat during ice storage.

Some of the pharmacological properties of phytosteryl ferulates may be linked to their antioxidant potential. In this study, 2,2-diphenyl-1-picrylhydrazyl (DPPH), electron spin resonance (ESR), and thiobarbituric acid–reactive substances (TBARS) assays demonstrated that phytosteryl ferulates such as cycloartenyl ferulate (CAF), 24-methylenecycloartanyl ferulate (24-mCAF), and β-sitosteryl ferulate (β-SF) and ferulic acid (FA) each exerted strong free radical scavenging and antioxidation of lipid membrane, which were comparable to α-tocopherol. However, the sterol moiety alone, such as cycloartenol (CA), had neither activity. Since, the reactive oxygen species (ROS) production in the cell complex defense mechanism cannot be ruled out with the cell free system, we measured ROS production in NIH 3T3 fibroblast cells induced by H2O2. CAF and ethyl ferulate (eFA) greatly decreased the ROS level in this system. CA also significantly inhibited the ROS level, suggesting that CA could inhibit ROS production in living cells. Besides these, CAF, 24-mCAF, β-SF, as well as eFA and CA, all these chemicals significantly inhibited the NF-κB activity as analyzed by measuring translocation of NF-κB p65 in LPS-stimulated RAW 264.7 macrophages. These observations revealed that phytosteryl ferulates are responsible for the antioxidant and anti-inflammatory activity via ROS scavenging and inhibition of ROS production. Keywords:: phytosteryl ferulate, cycloartenyl ferulate, NF-κB, antioxidant, reactive oxygen species (ROS)

The antioxidative property of a hydrophilic extract prepared from the fruiting body of edible mushroom ( Flammulina velutipes) was evaluated. The mushroom extract contained ergothioneine (ERT) at a level of 3.03 +/- 0.07 mg/mL, showed higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, and suppressed lipid oxidation of bigeye tuna meat more effectively than authentic L-ERT added at the same concentration. The authentic L-ERT had stronger total reducing power than the mushroom extract and inhibited the formation of metmyoglobin (metMb) more significantly in bigeye tuna meat. Lipid oxidation in beef and fish meats to which the mushroom extract had been added was "virtually" controlled during storage on ice. Ground beef and bigeye tuna meat with the extract added kept their natural colors unchanged for longer than 12 and 7 days of ice storage, respectively. Contrary to this, browning in meat color was observed in the control samples without the extract after 6 and 2 days of storage, respectively, when stored under similar conditions. There was significant correlation between meat color and chemical parameters, including total lipid hydroperoxides, thiobarbituric acid reactive substances, and metMb. However, there was no significant correlation between pH value and meat discoloration. These results suggest that ERT in the hydrophilic extract of F. velutipes plays an important role as a color stabilizer of meats.

Background and purpose: We have recently reported that phytosteryl ferulates isolated from rice bran inhibit nuclear factor-κB (NF-κB) activity in macrophages. In the present study, we investigated the effect of γ-oryzanol (γ-ORZ), a mixture of phytosteryl ferulates, cycloartenyl ferulate (CAF), one of the components of γ-ORZ, and ferulic acid (FA), a possible metabolite of γ-ORZ in vivo, on a model of colitis in mice.

Bacterial cold water disease, caused by Flavobacterium psychrophilum, is a serious problem in the aquaculture industry worldwide. Several methods to prevent and treat cold water disease have been studied. Although detection at the early stage of F. psychrophilum infection is very important for the prevention and treatment of cold water disease, an effective detection method has not yet been developed. The use of flow cytometry (FCM) for the rapid determination of bacterial cell numbers with high sensitivity is beginning to attract attention. Immunomagnetic separation (IMS) has also been used to detect F. psychrophilum. The purpose of the present study was to develop a method to quickly determine the number of bacterial cells by combining the FCM and IMS methods. Because samples can be more effectively concentrated using smaller magnetic beads and stronger magnetism, we used carbonyl iron powder as the magnetic beads for the IMS. The detection level of F. psychrophilum using FCM combined with IMS was 5 orders lower than that using FCM without IMS. The values determined using FCM combined with IMS strongly correlated with those obtained using the colony-counting method, in the range of approximately 10-10(8) colony-forming units per milliliter. One FCM assay could be completed within 60 s and the total assay time, including sample preparation, was less than 2 h. The combined method of FCM with IMS developed in this study can be used reliably for the rapid detection of F. psychrophilum.

Tropomyosin, a myofibrillar protein of 35-38 kDa, represents a major and cross-reactive allergen in decapod crustaceans. This study was initiated to clarify whether decapod-allergic patients also recognize tropomyosins of barnacles, crustaceans phylogenetically remote from decapods, which are locally consumed as a delicacy. On SDS-PAGE, a 37 kDa protein was observed in all the heated extracts prepared from two species of decapods (American lobster Homarus americanus and black tiger prawn Penaeus monodon) and two species of barnacles (acorn barnacle Balanus rostratus and goose barnacle Capitulum mitella). In immunoblotting, the 37 kDa protein was found to react with monoclonal antibodies against American lobster tropomyosin and hence identified as tropomyosin. The patient sera reacted to tropomyosins from both decapods and barnacles and the reactivity was abolished by preincubation with American lobster tropomyosin, demonstrating that barnacle tropomyosins are allergens cross-reactive with decapod tropomyosins. However, the amino acid sequence of acorn barnacle tropomyosin, deduced by cDNA cloning experiments, shares higher sequence identity with abalone tropomyosins than with decapod tropomyosins. In accordance with this, the phylogenetic tree made for tropomyosins from various animals showed that the acorn barnacle tropomyosin is evolutionally classified not into the decapod tropomyosin family but into the molluscan tropomyosin family.

NF-{kappa}B family of transcription factors are involved in numerous cellular processes, including differentiation, proliferation, and inflammation. It was reported that hydroxycinnamic acid derivatives (HADs) are inhibitors of NF-{kappa}B activation. Rice bran oil contains a lot of phytosteryl ferulates, one of HADs. We have investigated effects of phytosteryl ferulates on NF-{kappa}B activation in macrophage. Cycloartenyl ferulate (CAF), one of phytosteryl ferulates, significantly reduced lipopolysaccharide (LPS)-induced NO production and mRNA expression of inducible NO synthase and cyclooxygenese-2 but upregulated SOD activity. Electrophoresis mobility shift assay revealed that CAF inhibited DNA-binding of NF-{kappa}B. CAF and phytosteryl ferulates probably have potentially anti-inflammatory properties.

The present study investigated the effects of bleeding treatment and perfusion of antioxidant compounds on lipid oxidation in ordinary and dark muscles of yellowtail in the early stage of ice storage. The lipid hydroperoxide contents of dark muscles obtained from yellowtails with and without bleeding treatment were higher and increased more rapidly than those of ordinary muscles. There were no significant differences in the rates of change of the lipid hydroperoxide content (up to 48 h), fatty acid composition and metmyoglobin formation between dark muscles with and without bleeding treatment. Physiological saline containing ascorbic acid or 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox®) was perfused into live yellowtail or added to minced dark muscle. Trolox® significantly (P

Two types of murine monoclonal antibodies (MAbs) against American lobster ( Homarus americanus ) were generated and characterized. Three purified MAbs were characterized to be specific to the shellfish major allergen tropomyosin. MAbs 5G5E1 and 1A3A7 were reactive to tropomyosin from crustacean species only, whereas MAb 2A7H6 was reactive to both crustacean and mollusk tropomyosins. None of the antibodies reacted to vertebrate tropomyosins. Competitive ELISA indicated that the antigenic epitopes recognized by the two types of MAbs were different from each other. In addition, competitive immunoblot results showed that the binding of shellfish-allergic patient IgEs to lobster tropomyosin was inhibited by the MAb 2A7H6 only. This finding suggests that the antigenic epitope for the 2A7H6 antibody might be similar or close to the allergenic epitope shared by crustaceans and mollusks. Consequently, the MAbs recognizing the different common antigenic epiotopes obtained in the present study would not only facilitate the allergen characterization of shellfish, but may also be useful for the development of specific and sensitive immunoassays for allergen quantification or epitope mapping.

ブラックタイガー由来精製トロポミオシンを免疫原として，甲殻類トロポミオシンに特異的に反応するモノクローナル抗体を作製し，甲殻類トロポミオシン測定用のサンドイッチELISA法を確立した．本法では，甲殻類に分類されるえび類，かに類，やどかり類，おきあみ類のトロポミオシンとは交差率82～102％と全般的に反応したが，軟体動物に分類されるいか類，たこ類，貝類トロポミオシンとの交差率は0.1％未満であった．また，食品全般においても甲殻類以外で反応は認められなかった．検出感度は甲殻類由来総タンパク質として0.16ppmであり，食品表示に求められる数ppmレベルの測定に十分な感度であった．再現性もCV値10％未満であったことから，精度よく測定できると考えられた．さらに，食品由来成分の存在下においてもマトリックスの影響を受けないこと，加熱により変性を受けた場合にも測定可能なことを確認した．したがって，本法は甲殻類由来トロポミオシンに対して特異的であり，加工食品における甲殻類検知法として使用可能であると考えられた．

Summary It is well known that ayu (Plecoglossus altivelis) die after spawning. Their lifespan is known to be only 1 year; possibly one contributing factor to post-spawning mortality in ayu is the enhanced oxidative stress, probably inducing DNA damage and subsequent DNA repair systems (i.e. phosphorylated p53), which in turn may cause apoptosis and a shortened lifespan. To examine this possibility, we surveyed p53 and its phosphorylation state, oxidative DNA damage by measuring the levels of 8-hydroxy-2′-deoxyguanosine, and the induction of apoptosis by measuring levels of caspase-3, -9/6 in the brain at different stages. Accumulation of oxidative stress in brain DNA was accompanied by caspase-3, -9/6, and stimulates p53 through the phosphorylation of this p53 (specifically residue Ser 15) in ayu brain with aging.

By conducing organoleptic analysis, the authors investigated the effect of oil droplet size on human preference to the taste of oil-in-water (o/w) emulsions to which several tastants were added. Two singly dispersed o/w emulsions, different in oil droplet sizes, consisting of 10% triacilglycerol purified from tuna, sardine or soybean oil, 0.5% emulsifier and water were prepared by ceramic membrane filtration. Organoleptic analysis showed that the impressions of sweetness, bitterness and umami, which were developed by addition of certain taste substances, were different between o/w emulsions with different oil droplet sizes. The results of two-bottle choice tests, which were carried out using olfactory-blocked mice, showed that o/w emulsions with 1.00-μm droplets, with added sweet or bitter substances, were preferred to emulsion with 5.50-μm droplets. These results suggest that the droplet size of o/w emulsion remarkably influences certain taste impressions created by added taste substances.

Squid skin color is one of many important factors to evaluate market values. The effects of chilling and hypoxia treatments on skin color of Japanese common squid Todarodes pacificus and spear squid Loligo bleekeri were investigated to prevent highly fresh squids from abnormal fading skin color with inappropriate commercial value losses. Skin color of the squids gradually faded away during ice-cold storage. Measurements of chromato-phores expansion showed that skin color can be maintained well after death by keeping the bodies well-oxygenated and avoiding direct contact with ice.

A fluorescent image analysis method was developed to evaluate lipid hydroperoxide formation in fish muscle. The lipid hydroperoxides generated in white and dark fish muscles during storage at 5–6°C oxidized 3-perylene diphenylphosphine located in the tissue to yield the fluorescent derivative, 3-perylene diphenylphosphine oxide (3-PeDPPO). 3-PeDPPO thus obtained was determined by digital fluorescent image analysis. The 3-PeDPPO fluorescence intensity of white and dark muscle increased during low-temperature storage (0–24 h) and was clearly correlated with total lipid hydroperoxide levels in muscle extracts, which were determined by using HPLC based on a triphenylphosphine oxidation method (R 2=0.954). These results suggest that 3-PeDPPO fluorescence, coupled with fluorescent image analysis, is a novel tool for direct determination of lipid hydroperoxides in fish muscle without a need for extraction of lipid.

Changes in triacylglycerols (TAG) and phospholipids (PL) compositions of cooked Japanese sardine meats as such or with prior addition of ethylene diaminetetracetic acid (EDTA) or a combination of nitrite and ascorbate were evaluated during chilled storage using gas chromatography and selected ion monitoring gas chromatography/mass spectrometry. The TAG molecular species compositions remained unchanged, while certain species of PL molecular species changed during storage at 2 °C for 14 days. The PL containing polyunsaturated fatty acids were highly susceptible to autoxidation. The PL fractions play an important role in oxidative rancidity and development of off-flavor in cooked sardine meat, while TAG fraction plays a minor role in the oxidative deterioration of the meat. Changes in peroxide and thiobarbituric acid values were also monitored. Added EDTA was not effective in controlling the decomposition of lipid hydroperoxide throughout the storage period. However, a combination of NaNO 2 and ascorbate not only suppressed the formation but also the decomposition of the primary oxidation products.

To elucidate the effects of EDTA and a combined use of nitrite and ascorbate on oxidative rancidity of cooked Japanese sardine ( Sardinops melanostictus ) stored at refrigeration temperature (2 °C), changes in peroxide values (PV), thiobarbituric acid (TBA) value and fatty acid composition were monitored. The PV and TBA values of the meat with and without EDTA (250 mg/100 g meat) increased gradually, while they remained unchanged when a mixture of sodium nitrite (10 mg NO 2 /100 g meat) and sodium ascorbate (200 mg/100 g meat) was added. Total polyenoic acids in the nitrite and ascorbate mixture-treated meat decreased at a slower rate than in the control group. These changes in PUFA composition were due to differences in oxidative stability between the meats containing different antioxidants. In conclusion, a combined use of nitrite and ascorbate showed a greater antioxidativity in terms of the lower PV and TBA values than did EDTA and resulted in preventing the development of warmed-over flavour in cooked sardine during of 14 day refrigerated storage.

We investigated the role of lipid oxidation in the development of a rancid off-odor in the early stage of ice storage in both ordinary and dark muscles of cultured yellowtail (Seriola quinqueradiata). The total lipid hydroperoxide content and thiobarbituric acid-reactive substances (TBARS) of the dark muscle were significantly higher (P < 0.01) than those of the ordinary muscle during 2 d of ice storage. The increase in the metmyoglobin content of the dark muscle was accompanied by gradual darkening of the muscle color during ice storage. To distinguish the changes in odor characteristics of the muscles, sensory evaluation was carried out. Slight changes in the intensity of 7 different odors were noted in the ordinary muscles, and there was a significant increase in the overall, fishy, spoiled, and rancid smells of the dark muscle during 2 d of ice storage. No correlation was found between the total content of lipid hydroperoxide and the odor intensities in ordinary muscle; however, there was a significant correlation between the total lipid hydroperoxide content and rancid off-odor and overall smell intensities in the dark muscle. The rate of lipid oxidation of the yellowtail dark muscle was significantly faster than that of the ordinary muscle. Lipid oxidation of the dark muscle was closely related to meat darkening and development of the rancid off-odor during the early stage of ice storage.

Effects of twelve commercially available synthetic food colorants, including tartrazine, rose bengal, brilliant blue FCF, new coccin, amaranth, erythrosine B, phloxine B, indigo carmine, acid red, fast green FCF, allura red AC and sunset yellow FCF, on photosensitized oxidation of methyl linoleate (MeLe) were investigated. Rose bengal, erythrosine B and phloxine B accelerated oxidation of MeLe under light exposure and their pro-oxidative effects were concentration-dependent. Light exposure of MeLe with added colorants induced generation of hydroperoxide isomers, including 10-cis,trans- and 12-cis,trans-MeLe hydroperoxide, suggesting that the food colorants served as photosensitizers under the present conditions. The addition of α-tocopherol or β-carotene effectively suppressed the oxidation of MeLe, and their antioxidative effects were concentration-dependent. Neither α-tocopherol nor β-carotene altered the distributions of hydroperoxide isomers of MeLe. This study showed that the food colorants containing a xanthene skeleton increased their potential as photosensitizers with increase in both the number and atomic mass of halogen substituents on the xanthene skeleton.

Caloric restriction (CR) is the only established intervention that extends life span in mammals, insects and nematodes. One of the hypotheses suggested that most of the effects of CR on aging may be due to reduced oxidative stress at the cellular level. It was known that ayu (Plecoglossus altivelis) produced ROS higher than other fish and that the life span of ayu is only one year. The present study attempts to quantify age-associated changes of the degree of attenuation on oxidative damage and hormonal homeostases in CR. The levels of 8-OHdG as the oxidative DNA damage level and the caspase-9/6, -3-like activities as the induction factors of apoptosis with aging in brain and liver were surveyed. Caspase-like activities in brain and liver were reduced by CR, while CR had no influence on DNA damage level. However, life span of ayu was not prolonged by CR. These results suggested that there would be factors determining life span of ayu other than CR and apoptosis.

Volatile compounds formed by photosensitized oxidation and autoxidation of cod liver oil were compared. A 5-mL portion of oil-in-water emulsion (10% oil, 1% Tween 20 and 0.1 mM of rose bengal or 0.1 mM of ferrous chloride) was sealed into a 50-mL crimp top vial. The vial with added rose bengal was exposed to a 100-watt tungsten bulb (6000 lux) in an oven at 40°C, while the vial with added ferrous chloride was wrapped in aluminum foil to shield light and kept in the same oven. Volatiles in the headspace of the vials were collected by solid phase microextraction technique and analyzed with a gas chromatography-flame ionization detector and a gas chromatography — mass spectrometry. Approximately 51 kinds of volatiles were identified from oxidation of cod liver oil. All the volatiles identified in the sample with added rose bengal were identified in the sample with added ferrous chloride, however, tremendous differences of their relative ratios were found, which probably is useful to explain the flavor differences between sun-dried seafood and mechanical-dried seafood. The formation mechanisms of certain volatiles were proposed.

Food colorants including rose bengal, erythrosine B, phloxine B and cochineal extracts were added to Alaska pollack Theragra chalcogramma surimi which was previously added with methyl linoleate (MeLe) or ethyl eicosapentaenoate (EPA Et). All the surimi were exposed to a 100-watt light tungsten bulb (4500 lux) in a cold room at 5°C. Four isomeric hydroperoxides, including 13-cis, trans-, 13-trans, trans-, 9-trans,cis- and 9-trans,trans-MeLe hydroperoxides, were generated by oxidation of MeLe added to surimi with and without cochineal extracts after exposure to light for several hours. For the surimi containing rose bengal, erythrosine B and phloxine B, extracted lipids contained not only the above four hydroperoxide isomers but also 12-cis,trans-as well as 10-trans,cis- MeLe hydroperoxides. EPA Et added to surimi which contained rose bengal, erythrosine B and phloxine B generated characteristic isomeric hydroperoxides, including 6-cis,trans- and 17-cis,trans-EPA Et hydroperoxides due to 1O2 mediated oxidation. The pro-oxidative potentials of four food colorants in surimi against added EPA Et or MeLe increased as the order of cochineal extracts < phloxine B

The isomeric hydroperoxide distribution and the composition of volatiles generated by oxidation of all-cis-7,10,13,16,19-docosapentaenoic acid ethyl ester (DPA Et) were determined. DPA Et was prepared by using seal blubber oils as raw material and purified by urea complexation and reverse-phase high-performance liquid chromatography (HPLC). The DPA Et of over 96% purity thus obtained was dissolved in methanol and subsequently divided into two portions. One portion was added with methylene blue and exposed to a tungsten bulb light at 5 °C for photosensitized oxidation. The other portion was added with 2,2'-azobis (2,4-dimethylvaleronitrile) as an azo-radical initiator and kept in the dark at room temperature for autoxidation. Positional isomers of hydroperoxides generated by autoxidation or photosensitized oxidation of DPA Et were separated by normal-phase HPLC and detected by a fluorescence detection system as well as UV absorption. The peak components were identified by gas chromatography-mass spectrometry (GC-MS). Eight isomeric hydroperoxides, including certain amounts of 7-, 10-, 11-, 13-, 14-, 16-, 17-, and 20-hydroperoxy docosapentaenoate, were generated by autoxidation of DPA Et. The photosensitized oxidation of DPA Et yielded not only the above eight hydroperoxide isomers but also two additional isomeric hydroperoxides, 8- and 19-hydroperoxy docosapentaenoate, which are characteristic hydroperoxide isomers generated by singlet oxygen-mediated oxidation. Volatiles formed by autoxidation of DPA Et at 50 °C were collected and analyzed by solid-phase micro-extraction and GC/GC-MS. A number of aldehydes, ketones, alcohols, acids, furans and hydrocarbons were identified. The formation mechanisms of certain volatiles are discussed.

Seafood allergy is a common and major cause of food allergy in aduits. In recent years, seafood allergy has become a serious problem with the increase of seafood consumption. To develop a rapid allergen detection method based on the affinity of antigen-antibody interaction, fish major allergen, parvalbumin, was used for kinetic analysis by a surface plasmon resonance (SPR) biosensor. Anti-parvalbumin murine monoclonal antibody (MAb) EGB was immobilized onto s carboxymethyl dextran (CMD) surface. By the injection of various concentrations of purified carp parvalibumin (GPa), a standard curve and the affinity consiants (K n and k ag ) for the MAb EGB-CPa model system were determined. In addition, kinetic data were also obtained by the injection of serial dilutions of extracts from seafood products: sardine fish cake (tsumire) and dried skipjack tuna (katsuonut). Sardine tsumire and katsuonst contained 0.11 mg/kg and 0.39 mg/kg parvalbumins, respectively, where affinity constants K s and k xes were almost similar among parvalbomins from different sources. In the SPR system, the allergen can be detected only for 5 min according to the allergen-MAb binding interaction. Consequently, by the use of a SPR biosensor, kinetic analysis based an the allergen specific MAb would be a rapid and powerful tool for allergen detection and quantification.

The differences in distribution of geometric isomers of unsaturated PC hydroperoxides generated by free radical oxidation were compared, as corresponding hydroxy analogs, in heterogeneous liposomes and in a homogeneous methanol solution by using HPLC with UV detection due to the presence of conjugated dienes. Identification of fractionated peak components was carried out by GC-MS. When the oxidation of 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine, PC(16:0/18:2), was initiated in liposomes by a hydrophilic azo radical initiator, and in a methanol solution by a hydrophobic azo radical initiator, there was no significant difference in the relative percentages of 1-palmitoyl-2-(9-hydroxy-trans-10,trans-12-octadecadienoyl)-sn-glycero-3-phosphocholine (9-t,t-OH PC) and 1-palmitoyl-2-(13-hydroxy-trans-9,trans-11-octadecadienoyl)-sn-glycero-3-phosphocholine (13-t,t-OH PC) between the PC oxidized in liposomes and in the methanol solution. For the oxidation of 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine, PC(16:0/20:4), the relative percentage of 1-palmitoyl-2-(5-hydroxy-trans-6,cis-8,11,14-eicosatetraenoyl)-sn-glycero-3-phosphocholine (5-OH PC) was significantly higher (P0.01) than that of 1-palmitoyl-2-(15-hydroxy-cis-5,8,11,trans-13-eicosatetraenoyl)-sn-glycero-3-phosphocholine (15-OH PC) in liposomes. For the homogeneous methanol solution of PC(16:0/20:4), the relative percentage of 5-OH PC was close to that of 15-OH PC. For the PC(16:0/20:4) oxidized in bulk with added pentamethylchromanol, the individual amount of 15-OH PC, 1-palmitoyl-2-(11-hydroxy-cis-5,8,trans-12,cis-14-eicosatetraenoyl)-sn-glycero-3-phosphocholine (11-OH PC), 1-palmitoyl-2-(12-hydroxy-cis-5,8,trans-10,cis-14-eicosatetraenoyl)-sn-glycero-3-phosphocholine (12-OH PC), 1-palmitoyl-2-(8-hydroxy-cis-5,trans-9,cis-11,14-eicosatetraenoyl)-sn-glycero-3-phosphocholine (8-OH PC), 1-palmitoyl-2-(9-hydroxy-cis-5,trans-7,cis-11,14-eicosatetraenoyl)-sn-glycero-3-phosphocholine (9-OH PC), and 5-OH PC were close to each other compared to the corresponding values in liposomes and in methanol solution. The results obtained by gel permeation chromatography of the PC liposomes containing hydrophilic 2,2'-azobis-2-amidinopropane) dihydrochloride (AAPH) suggest that the AAPH added to the liposomes of PC(16:0/20:4) was partitioned into the water phase and out of the hydrophobic region of the fatty acyl moieties of the PC. These results confirm that the distance that exists in the bis-allylic carbons of the unsaturated fatty acyl moieties of PC from the interface between the hydrophilic region of PC and the water phases played an important role in influencing hydrogen abstraction to form a symmetrical distribution of hydroperoxide isomers in both the heterogeneous liposomes and the homogeneous methanol solution.

‘Enokitake’ mushroom ( Flammulina velutipes ) extracts were prepared by three different solvents: 70 mL/100 mL acetone, 70 mL/100 mL ethanol as well as hot water. Effects of the extracts on mushroom tyrosinase activity and browning of apple were investigated. Mushroom tyrosinase activities assayed spectrophotometrically and by oxygen uptake were found to be inhibited significantly by all three extracts. Lyophilized ‘enokitake’ fruit body powder inhibited the browning of fresh apple. Immersing sliced apple into the acetone extract was found to prevent effectively the browning development. Freshly squeezed apple juice with added hot-water extract showed the concentration-dependent inhibition of browning. No browning was observed on the apple juice when mixed with the extract containing 1.0 g wet ‘enokitake’/mL in a mixture. Under the same conditions, no significant changes in color in terms of a* and b* values of the mixture were observed for up to 6 h. These observations suggested that ‘enokitake’ mushroom contained certain compounds which inhibited mushroom tyrosinase activity and the development of browning induced by the catalytic oxidation due to polyphenol oxidase.

1998年の3月から12月に水揚げされた紋別産ホタテガイについて,貝柱成分の季節変化を調べた。貝柱重量とグリコーゲン量は,春から夏にかけて増加し,冬に減少した,タンパク質量は10月に最大となったが,一個当たりのタンパク質量は8月に最大となった。グリコーゲンとタンパク質の無水物量は負の相関関係を示した。ATPおよび関連化合物量と遊離アミノ酸量はそれぞれ7月と6月に最も高くなった。グルタミン酸量は産卵後の5月に顕著に高い値であったが,グリシン,アラニン,アルギニン,プロリン量は夏季に多い傾向を示した。これら貝柱成分の季節変動から,この地域のホタテガイの旬は夏季と考えられた。

The present novel approach consists of two stages: in the first stage the many-electron states of a CuO6 octahedron or a CuO5 pyramid are calculated by the first-principles variational method, by taking into account the local distortions of a CuO6 octahedron or a CuO5 pyramid. In the second stage a metallic state is constructed in the presence of the local AF ordering constructed by the localized spins. In this metallic state the local distortions are treated in the mean field approximation, so that a “pseudopolaronic effect” is taken into account. Based on this approach, the hole-concentration dependence of Tc and the isotope effect are calculated for LSCO, and compared with experimental results. This approach leads to d-wave pairing mechanism.

As a widely distributed and natural existing antioxidant, ferulic acid and its functions have been extensively studied in recent decades. In the present study, hypertrophic growth of fast skeletal myofibers was observed in adult zebrafish after ferulic acid administration for 30 days, being reflected in increased body weight, body mass index (BMI), and muscle mass, along with an enlarged cross-sectional area of myofibers. qRT-PCR analyses demonstrated the up-regulation of relative mRNA expression levels of myogenic transcriptional factors (MyoD, myogenin and serum response factor (SRF)) and their target genes encoding sarcomeric unit proteins involved in muscular hypertrophy (skeletal alpha-actin, myosin heavy chain, tropomyosin, and troponin I). Western blot analyses detected a higher phosphorylated level of zTOR (zebrafish target of rapamycin), p70S6K, and 4E-BP1, which suggests an enhanced translation efficiency and protein synthesis capacity of fast skeletal muscle myofibers. These changes in transcription and translation finally converge and lead to higher protein contents in myofibers, as confirmed by elevated levels of myosin heavy chain (MyHC), and an increased muscle mass. To the best of our knowledge, these findings have been reported for the first time in vivo and suggest potential applications of ferulic acid as functional food additives and dietary supplements owing to its ability to promote muscle growth.

γ-オリザノールのアスタキサンチン含有飼料によるブリの肉変色抑制作用に及ぼす影響について検討を加えた。2 ヵ月間アスタキサンチンあるいはアスタキサンチンと γ-オリザノールを投与し，水揚げ後，切り身を 4°C で 48 時間貯蔵して血合筋の色調の変化を解析した。その結果，γ-オリザノールとアスタキサンチンの同時投与で，魚肉変色抑制効果が最も高いことが明らかとなった。

Pufferfish accumulate tetrodotoxin (TTX) mainly in the liver and ovary. This study aims at investigating the effect of TTX accumulation in the liver of cultured specimens of torafugu Takifugu rubripes on the hepatic gene expression by microarray analysis on Day 5 after the intramuscular administration of 0.25 mg TTX/kg body weight into the caudal muscle. TTX was detected in the liver, skin and ovary in the TTX-administered individuals. The total amount of TTX accumulated in the body was 67 ± 8% of the administered dose on Day 5. Compared with the buffer-administered control group, a total of 59 genes were significantly upregulated more than two-fold in the TTX-administered group, including those encoding chymotrypsin-like elastase family member 2A, transmembrane protein 168 and Rho GTP-activating protein 29. In contrast, a total of 427 genes were downregulated by TTX administration, including those encoding elongation factor G2, R-spondin-3, nuclear receptor activator 2 and fatty acyl-CoA hydrolase precursor. In conclusion, our results demonstrate that the intramuscular administration of TTX changes the expression of hepatic genes involved in various signaling pathways.

We analyzed differences in some physicochemical parameters of proteins in shoulder rose (M. Cutaneous-omo brachialis) muscle as a result of beef processing to produce pastirma. Samples from processed muscles showed significantly increased concentrations of extracted proteins, especially of H2O P-ex and Guba-Straub–adenosine triphosphate solution (P < 0.01), as a result of the salting–curing process. The salt-curing process was likely to have an important effect on the extractability of muscle proteins such as myosin heavy chain (MHC) and water-soluble proteins, possibly as a result of releasing some proteins from each other and cleaving the structures between certain proteins. The fluorescence intensities of processed samples were higher than those of the control samples at all guanidine hydrochloride concentrations. The hydrophobicity also increased on account of new compounds that were created during the pastirma-making process. Since the process of making pastirma lasts about 4 weeks (drying), the metmyoglobin content was greatly increased in pastirma samples compared with the unprocessed samples (by as much as 57 %). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis results conceived that during processing of pastirma products, MHC and other muscle proteins degraded into polypeptides with smaller molecular weight lower than 15-kDa. The results of this study demonstrated that meat processing promoted the enzymatic digestion of some proteins, and the differences in composition between the control and pastirma samples were thus likely to be owing to protein degradation. The traditional pastirma-making process hence has no negative impact on the structure of the muscle and produces a firmer-textured.

Rice is one of the world's most important food crops, and more than half the people in the world eat rice as the main part of their diet. Rice bran is a component of raw rice that is obtained when it is removed from the starchy endosperm in the rice milling process. Antioxidants in rice bran have professed health benefits, as well as antioxidant characteristics for improving the storage ability of food additives for further health benefits. These antioxidants possess promising health-related benefits in the prevention of various diseases, including cancer, inflammatory bowel disease, hyperlipidemia, fatty liver, hypercalciuria, kidney stones, gastrointestinal ulcers, rheumatism, and heart disease, and also in postmenopausal syndrome, etc. In addition, extract from rice bran increases adiponectin secretion, which indicates its potential use for treatment of atherosclerosis and type 2 diabetes. Moreover, γ-oryzanol is widely used as an anabolic drug by bodybuilding athletes.

Sweet smelt Plecoglossus altivelis (Temminck et Schlegel) were fed with diets containing 0.01% or 1% α-tocopherol for 14 weeks to investigate whether an excess dose of α-tocopherol effected several biological functions of fish. The different concentrations of α-tocopherol in fish diets did not affect fish body weight or length, or fatty acid composition of fish blood. However, the accumulation of hydroperoxides in plasma and erythrocytes of fish fed 1% α-tocopherol was significantly higher than those of fish fed 0.01% α-tocopherol. The osmotic fragility of fish erythrocytes showed the opposite result. These results suggest that an excess dose of dietary α-tocopherol promoted lipid peroxidation, increasing the accumulation of hydroperoxides in fish blood but reducing the erythrocyte osmotic fragility.

A brief review on the Kamimura–Suwa (K–S) model is first given. Then it is shown that an observed peculiar doping dependence of electronic entropy is explained by the K–S model successfully. Further it is shown on the basis of the K–S model that the phonon-mediated d-wave superconductivity is possible in LSCO.

Sweet smelt was reared at two fishery experimental stations for 5 months from June to October. Every 2 weeks blood was collected from the caudal vessels and, subsequently, the phosphatidylcholine hydroperoxide contents and the fatty acid compositions in the blood were determined by high-performance liquid chromatography and gas chromatography, respectively. The seasonal variation of the contents of accumulated hydroperoxides and fatty acids in the sweet smelt blood were observed in both experimental stations. Sweet smelt started performance of cucumber-like or watermelon-like aroma in the middle of July and the aroma was enhanced in August. The content of phosphatidylcholine hydroperoxides and the amount of total fatty acid in the fish blood, in terms of possible precursors of volatile compounds, were also extremely high in the same period. According to lipid peroxidation mechanisms, the strong characteristic aroma of sweet smelt during July to August might be due to the high contents of accumulated lipid hydroperoxides and polyunsaturated fatty acids in their tissues.

A nonylphenol-assimilating bacterium isolated at a sewage-treatment plant in Tokyo was studied phenotypically, genotypically and phylogenetically. Analysis of the 16S rDNA sequence, the G+C content of the DNA (63 mol%) and the isoprenoid quinone composition, as well as the presence of sphingoglycolipid and the whole-cell fatty acid profile, revealed that the isolate is a member of the genus Sphingomonas. However, the sequence similarity of the 16S rDNA with that of known Sphingomonas spp. was found to be at most 96%, implying that the isolate is distinctive. Furthermore, the results of DNA-DNA hybridization experiments and its physiological characteristics clearly indicated that the isolate represents a new Sphingomonas species, for which the name Sphingomonas cloacae is proposed; strain S-3T (= JCM 10874T = IAM 14885) is the type strain.

Hydroxy fatty acid isomers derived from phosphatidylcholine hydroperoxides (PC-OOH) in the livers of three fish species, including sweet smelt, yellowtail and rainbow trout, were determined by selected ion monitoring of gas chromatography/mass spectrometry. Total molar amounts of all hydroxy fatty acids determined in the present study coincided well with those of PC-OOH reported previously, suggesting that hydroxy fatty acid composition reflects hydroperoxide composition. The total amount of hydroperoxide isomers accumulated in the livers of sweet smelt was much higher than those of yellowtail and rainbow trout. The amounts of certain isomers, including 10-hydroperoxy octadecanoic acid, 12-hydroperoxy eicosanoic acid and 14-hydroperoxy docosanoic acid, were significantly higher than those of rainbow trout and yellowtail. These results suggest that differences in the contents and compositions of certain hydroperoxide isomers, which are possible precursors of a watermelon-like or cucumber-like aroma, result in differences of fresh fish aroma between aromatic fish and non-aromatic fish.

1997年6月, 9月, 11月及び1998年4月に水揚げされたホタテガイの貝柱について, 0℃貯蔵中の硬化発生率, ATP関連物質, L-アルギニンおよびオクトピンの変化を調べた。9月のホタテガイでは, 4月のものに比べてATPとpHの低下, 硬化の発現, オクトピンの蓄積が著しく速かった。ホタテガイ貝柱は水揚げする時期によって, 硬化による品質低下が異なることが明らかとなった。ホタテガイ水揚げ時の海水温度は, 9月では18.8℃, 4月では4.4℃であった。このため, ホタテガイの棲息海水温度と貯蔵温度との差が貝柱の硬化に大きく影響していたと推定される。

In this paper we will show that the microscopic origins of the "high-energy" pseudogap and of the peculiar hole-concentration dependence of the electronic entropy correspond to a phase change between a phase consisting of the small Fermi surfaces and a phase with a large Fermi surface. In real materials, however, the phase change is not sharp due to the finite spin-correlation length for local antiferromagnetic ordering. Further we will show that the dopant hole carriers in cuprates behave like heavy fermions.

Nonylphenol (NP) is an important intermediate in the production of various commercial and industrial materials, but is also known as a ubiquitous pollutant in urban aquatic environments. We recently studied the NP-degrading activities of microflora in several aquatic environments, and found a notable degrading activity for wastewater from a sewage treatment plant in Tokyo. This result led us to isolate NP-degrading microbes and identify biodegradation products. Using conventional plate culture techniques and molecular biological methods, Pseudomonas and Sphingomonas species, which are known for their degradation activities of many aromatic compounds, have been isolated. But it has also been found that Sphingomonas sp. (S-strain) is necessary and sufficient for the degradation of NP. Although the role of Pseudomonas sp. (P-strain) remains unclear, P-strain seems to provide some co-nutrients for the growth of S-strain. The degradation products were analyzed by GC/MS and NMR. More than 95% of NP was degraded within 10 days and aromatic compounds other than NP were not found, suggesting that the phenolic part of NP was completely degraded. We also examined the potential of S-strain for bioremedial applications. S-strain cells immobilized on chitosan or alginate beads retain their NP-degrading activity in flask-scale experiments. Furthermore, the chitosan-bound cells in a lab-scale bioreactor have been found to be persistent for repeated use, suggesting that S-strain is applicable to the treatment of NP-contaminated wastewater.

In this paper the energy difference between the phase consisting of the small Fermi surface and that of a large Fermi surface is calculated as a function of the hole concentration on the basis of the Kamimura-Suwa model. The calculated results are compared with “high energy pseudogap” data.

SUMMARY: Levels of phosphatidylcholine hydroperoxide (PC-OOH) in plasma, red blood cell (RBC), and livers of cultured and commercially available marine and freshwater fish were determined quantitatively by normal phase high-performance liquid chromatography (HPLC) equipped with a post-column detection system, using diphenyl-1-pyrenyl phosphine as a fluorescence reagent. The levels of plasma PC-OOH in non-aromatic fish, including yellowtail, amberjack, the Japanese flounder, sea bream, and rainbow trout ranged between 1.2 and 5.1 nmol/mL plasma. In contrast, the levels of PC-OOH in the plasma of aromatic fish, including the Japanese smelt, rainbow smelt, shishamo smelt, and sweet smelt were extremely high. The sweet smelt plasma contained the highest amount of hydroperoxide, amounting to 29.4 nmol/mL plasma. The levels of PC-OOH in non-aromatic fish RBC were low, ranging between 23.4 and 25.2 fmol/105 RBC. In contrast, a large amount of PC-OOH accumulated in all of the aromatic fish RBC used in the present study, ranging between 122 and 419 fmol/105 RBC. The PC-OOH levels in the sweet smelt and the Japanese smelt RBC were markedly high. The sweet smelt liver also contained a large amount of PC-OOH, amounting to 670 nmol/g tissue. This value was five times higher than those of some non-aromatic fish. Any marked difference in the contents of phospholipids and polyunsaturated fatty acids in the blood of sweet smelt and rainbow trout was not recognized. These results suggest that biogeneration of lipid hydroperoxide is an initial step in the development of certain volatile compounds in the aromatic fish.