Naoyuki Maeda

鶏挽肉に食塩，米麹，水および酵素剤を混合後，加熱タイプと非加熱タイプ（UCW）のチーズホエイ（CW）と醤油用酵母（SSY）接種の有無が異なる計8 種類のもろみを調製し，35°Cで24 週間発酵させた．発酵中のもろみと火入れ・ろ過後の最終製品の物理化学的性状，最終製品の呈味成分および味覚センサによる呈味性の評価（MTS）を行った．その結果，CWを利用した鶏肉発酵調味料（CW-CFS）では発酵中にもろみのL*値やpH 値は低下し，b*値や全窒素分は増加した．これらの傾向はUCW 使用区で顕著であった．遊離アミノ酸や有機酸総量はうま味と正の相関が認められた．MTS データの主成分分析バイプロットからCW発酵調味料（CWFS），CFS，CW-CFSでの味の識別が可能となった．SSY接種により，試料間でうま味，原料由来の苦み，酸味および塩味に差異を生じた．

The hepatitis E virus (HEV) causes a common infectious disease that infects pigs, wild boars, deer, and humans. In most cases, humans are infected by eating raw meat. Some essential oils have been reported to exhibit antiviral activities. In this study, in order to investigate the anti‐HEV properties of essential oils, the immunoreactivities of HEV antigen proteins against the relevant antibodies were analyzed after the HEV antigens underwent treatment with various essential oils. The essential oils extracted from the tea tree, which was previously reported to exhibit antiviral activity, lavender, and lemon had strongly reduced activity. We found that treatment with the essential oil prepared from Sakhalin spruce was associated with the strongest reduction in immunoreactivity of HEV antigen protein(s) among the tested substances. The main volatile constituents of Sakhalin spruce essential oil were found to be bornyl acetate (32.30 %), α‐pinene (16.66 %), camphene (11.14 %), camphor (5.52 %), β‐phellandrene (9.09 %), borneol (4.77 %), and limonene (4.57 %). The anti‐HEV properties of the various components of the essential oils were examined: treatment with bornyl acetate, the main component of Sakhalin spruce oil, α‐pinene, the main component of tea tree oil, and limonene, the main component of lemon oil, resulted in a strong reduction in HEV antigen immunoreactivity. These results indicate that each main component of the essential oils plays an important role in the reduction of the immunoreactivity of HEV antigen protein(s); they also suggest that Sakhalin spruce essential oil exhibits anti‐HEV activity. In a formulation with the potential to eliminate the infectivity of HEV in foodborne infections, this essential oil can be applied as an inactivating agent for meat processing and cooking utensils, such as knives and chopping boards.

This study investigated the development of fermented meat sauce from pig kidneys (PKs) to promote the use of underutilized livestock byproducts. To this end, we examined the effect of ureter removal and soy sauce yeast (SSY) inoculation on the physicochemical characteristics of the PK sauce mashes (moromis) and the quality of the final products. Ureter removal resulted in a decrease in the L* value of the moromis and an increase in the a* and b* values during the fermentation process. In contrast, SSY inoculation caused the opposite effect in CIE Lab color parameters. A principal component analysis with taste sensor data from the final products after heat treatment and filtration showed that the differences in taste among the four final products were distinguishable. The umami and bitterness tastes were derived from the fermentation of pig kidney sauce and enhanced with SSY inoculation and ureter removal, respectively.

Diethylstilbestrol (DES) is a synthetic oestrogen known to disrupt the endocrine system and to cause reproductive toxicity mediated via the hypothalamic‐pituitary‐adrenal axis; however, its molecular mechanism of action is poorly understood. In the present study, we found that, after only 1 week of exposure to DES, blood testosterone dramatically decreased and that this decrease was associated with a strong induction of prolactin (PRL). Even with the increase in PRL, the luteinising hormone and follicle‐stimulating hormone mRNAs slightly decreased. Our results show that, after 48 hours of a single dose of DES, there was a six‐fold increase in PRL expression. After exploring the upstream mechanisms, we determined that dopamine, which inhibits PRL secretion in male rats, did not decrease in the pituitary gland of DES‐treated rats, whereas vasoactive intestinal peptide (VIP), which mediates the acute release of PRL, was elevated. Serotonin (5‐HT) increased in the brain of male rats 24 hours after a single DES treatment; however, PRL, VIP or 5‐HT was not induced by DES in female rats. Our results indicate that DES induces the expression of pituitary PRL in male rats by stimulating VIP in the hypothalamus and 5‐HT in the central nervous system.