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Traditional Japanese koji-fermented tofu (tofuyo) processing was simulated to make fermented seafood. The koji fermentation process at room temperature was applied to steamed surimi and kamaboko to develop new types of food, extend their shelf life and improve their health-promoting effects. Extractive nitrogen and sugar contents, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, copper-reducing activities, and angiotensin-converting enzyme (ACE) inhibitory activity significantly increased after fermentation. These increases were the highest in kamaboko. Kamaboko fermented for 6 months had the highest DPPH radical scavenging, copper-reducing activities, and ACE inhibition. Kamaboko fermented for 6 months showed statistically the same copper-reducing power and ACE inhibition to tofuyo, but significantly higher DPPH radical scavenging activity. Size-exclusion chromatography showed the same peak(s) analyzed as Lowry-reactive substances, ninhydrin-reactive substances, sugar, and DPPH radical scavenging activity. The most antioxidative fraction had a molecular weight of 900–1300 and a sugar and amino acid structure(s). There was no specific ACE inhibitory fraction(s). The koji fermentation process at room temperature did not need additional energy, led to different foods with a sweet and a umami-rich taste and a soft texture. Additionally, koji fermented steamed surimi and kamaboko effectively prolonged best-before periods of up to 6 months.

To utilise Atlantic salmon, Coho salmon, Alaska pollack, and southern blue whiting as components of neutraceutical food and to clarify the potential physiological function of those fishes, their muscles were hydrolysed with pepsin, pancreatin or thermolysin. Methanolic extracts of fish muscle and their hydrolysates were prepared for analysis of angiotensin converting enzyme (ACE) inhibitory and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities. Pepsin hydrolysates of all the fish samples did not increase degree of hydrolysis, extractive nitrogen content and bioactivities. Pancreatin and thermolysin improved the ACE inhibitory activity, and the activity was expressed following the peak of size exclusion chromatography (SEC). The DPPH radical scavenging activity was increased following pancreatin and thermolysin hydrolysis, but this activity was not related to the SEC result. Except for the lower DPPH radical scavenging activity of Alaska pollack pancreatin hydrolysate than those of the others, there was no significant difference in the ACE inhibitory and DPPH radical scavenging activities by fish species.

Surimi is stabilized minced fish meat that is washed with water and blended with cryoprotectants. In this study, surimi from southern blue whiting (Micromesistius australis), surimi not subjected to washing entailing several changes of cryoprotectants following Patent WO/2003/013280 (hereafter termed unwashed surimi), heated surimi samples, and their hydrolysates were prepared to compare their compositions and bioactivities. Methanolic extracts of surimi and their hydrolysates were prepared for further analysis. The heated surimi samples showed different characteristics from the raw materials and released amino acids with enzymatic treatment. Unwashed surimi showed a significantly stronger 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity than surimi, and its effect on radical scavenging was compatible with that of southern blue whiting muscle. There was no significant difference in angiotensin converting enzyme inhibitory activity between unwashed and washed surimi. Soybean lipoxygenase was inhibited by heated unwashed surimi, indicating that unwashed surimi can be used for soymilk and its products.

生あごを塩干しした干しあごと焼き干しした焼きあごについてエキス成分を比較した。干しあごでは天日乾燥により生あごよりもIMPが減少し, また, 生あごに大量に含まれた遊離Hisも一部減少したが, 他の遊離および結合アミノ酸は増加し, とくにGlu, Asp, Ala, Lys, Argなどうま味に富む遊離アミノ酸類が著しく増加した。多量に残存するHisも他のアミノ酸と共存するときうま味を与え, 多量の乳酸, NaClも呈味に関与すると思われるが, 結局干しあごの呈味にはおもに多量に増加した遊離アミノ酸系の成分と水分の減少による濃厚化が大きく寄与している。焼きあごは製造の際, 最初の焼く工程でIMPが著しく増加し, クレアチニンも増加したが, 遊離アミノ酸類は減少し, 酵素の失活により乾燥工程ではほとんどアミノ酸類は増加しなかった。焼きあごエキスには多量のIMPが含まれ, カツオ節と共通した呈味成分を多くもつ良好な出しのもとである。

Cross-talk between G protein-coupled receptor (GPCR) signaling pathways serves to fine tune cellular responsiveness by neurohumoral factors. Accumulating evidence has implicated nitric oxide (NO)-based signaling downstream of GPCRs, but the molecular details are unknown. Here, we show that adenosine triphosphate (ATP) decreases angiotensin type 1 receptor (AT 1 R) density through NO-mediated S-nitrosylation of nuclear factor κB (NF-κB) in rat cardiac fibroblasts. Stimulation of purinergic P2Y 2 receptor by ATP increased expression of inducible NO synthase (iNOS) through activation of nuclear factor of activated T cells, NFATc1 and NFATc3. The ATP-induced iNOS interacted with p65 subunit of NF-κB in the cytosol through flavin-binding domain, which was indispensable for the locally generated NO-mediated S-nitrosylation of p65 at Cys38. β-Arrestins anchored the formation of p65/IκBα/β-arrestins/iNOS quaternary complex. The S-nitrosylated p65 resulted in decreases in NF-κB transcriptional activity and AT 1 R density. In pressure-overloaded mouse hearts, ATP released from cardiomyocytes led to decrease in AT 1 R density through iNOS-mediated S-nitrosylation of p65. These results show a unique regulatory mechanism of heterologous regulation of GPCRs in which cysteine modification of transcriptional factor rather than protein phosphorylation plays essential roles.

ギンナンを長期間室温に貯蔵するとき起こる品質の劣化と, その成分変化との関連を調べるために, ギンナンを低温 (5℃), 室温 (20～35℃), 高温 (37℃) の三つの条件の下で, それぞれ5月初旬から10月下旬まで6カ月間貯蔵し, その間2カ月ごとに一部を取り出して水分, フィチン酸量, ペクチン量, 総脂質量, 脂質中の脂肪酸組成の変化を調べた。