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101.
Takaya Y Furukawa T Miura S Akutagawa T Hotta Y Ishikawa N Niwa M 《Journal of agricultural and food chemistry》2007,55(1):75-79
Constituents in a distillation residue of Awamori (millet spirits) and their antioxidant activity are investigated in this study. The supernatant of the distillation residue obtained by centrifugation was partitioned with n-hexane, chloroform, ethyl acetate, and n-butanol against water to afford the corresponding solubles. Among them, n-hexane and chloroform solubles showed higher antioxidant potency than l-ascorbic acid by the bleomycin-Fe method. In chloroform solubles, seven cyclic dipeptides were identified along with ethyl 2-pyrrolidione-5-carboxylate, tyrosol, and ethyl p-hydoroxyphenyllactate. Antioxidant activity of ethyl p-hydoroxyphenyllactate was 4.2 times that of l-ascorbic acid, whereas cyclic dipeptides showed activity 0.89-1.29 times as strong as that of l-ascorbic acid. On the other hand, scavenging effect of cyclic dipeptides against O(2)(-.) and OH(.) by using electron spin resonance was also investigated. In the results, cyclo(l-Ile-l-Pro) showed significantly strong inhibitory effect against OH(.) (95.4% at 2.5 x 10-3 M) and cyclo(l-Phe-l-Pro), cyclo(l-Pro-l-Val), and cyclo(l-Leu-l-Pro) inhibited OH(.) 64.9, 54.1, and 51.0%, respectively, whereas alpha-tocopherol showed 37.7% inhibition, though only a few cyclic dipeptides weakly inhibited O(2)(-.). 相似文献
102.
Fujii H Nakagawa T Nishioka H Sato E Hirose A Ueno Y Sun B Yokozawa T Nonaka G 《Journal of agricultural and food chemistry》2007,55(4):1525-1531
Controlled acid-catalyzed degradation of proanthocyanidin polymers in grape seeds together with L-cysteine led to oligomeric proanthocyanidin-L-cysteine complexes along with monomeric flavan-3-ol derivatives being isolated, and their structures were confirmed on the basis of spectroscopic data and by chemical means. In addition, comparative studies on the antioxidative and survival effects of oligomeric proanthocyanidin-L-cysteine complexes and proanthocyanidin polymers were performed. The oligomeric proanthocyanidin-L-cysteine complexes showed higher bioavailability and antioxidant capacity and enhanced survival time in the animal test groups. In addition, it is suggested that the oligomeric complexes may help to prevent oxidative stress and may reduce free radical production. 相似文献
103.
Taguchi H Watanabe S Hirao T Akiyama H Sakai S Watanabe T Matsuda R Urisu A Maitani T 《Journal of agricultural and food chemistry》2007,55(5):1649-1655
Kiwifruit (Actinidia deliciosa and Actinidia chinensis) is allergenic to sensitive patients, and, under Japanese regulations, it is one of the food items that are recommended to be declared on food labeling as much as possible. To develop PCR-based methods for the detection of trace amounts of kiwifruit in foods, two primer pairs targeting the ITS-1 region of the Actinidia spp. were designed using PCR simulation software. On the basis of the known distribution of a major kiwifruit allergen (actinidin) within the Actinidia spp., as well as of reports on clinical and immunological cross-reactivities, one of the primer pairs was designed to detect all Actinidia spp. and the other to detect commercially grown Actinidia spp. (i.e., kiwifruit, Actinidia arguta, and their interspecific hybrids) except for Actinidia polygama. The specificity of the developed methods using the designed primer pairs was verified by performing PCR experiments on 8 Actinidia spp. and 26 other plants including fruits. The methods were considered to be specific enough to yield target-size products only from the target Actinidia spp. and to detect no target-size products from nontarget species. The methods were sensitive enough to detect 5-50 fg of Actinidia spp. DNA spiked in 50 ng of salmon testis DNA used as a carrier (1-10 ppm of kiwifruit DNA) and 1700 ppm (w/w) of fresh kiwifruit puree spiked in a commercial plain yogurt (corresponding to ca. 10 ppm of kiwifruit protein). These methods would be expected to be useful in the detection of hidden kiwifruit and its related species in processed foods. 相似文献
104.
Kodama S Yamamoto A Sato A Suzuki K Yamashita T Kemmei T Taga A Hayakawa K 《Journal of agricultural and food chemistry》2007,55(16):6547-6552
Chiral resolution of isoxanthohumol (IX) in beer samples was performed by hydroxypropyl-gamma-cyclodextrin-modified micellar electrokinetic chromatography. The optimum running conditions were found to be 20 mM phosphate buffer (pH 7.0) containing 45 mM hydroxypropyl-gamma-cyclodextrin and 100 mM sodium dodecyl sulfate with an effective voltage of +20 kV at 20 degrees C using direct detection at 210, 295, and 370 nm. IX was detected in 12 beer samples and the total levels of (+)- and (-)-IX ranged from 0.15 to 1.4 mg/L. But the amount of xanthohumol (XN) was below the detection limit (0.017 mg/L). Each level of (-)-IX was almost the same as that of (+)-IX, suggesting that IX was a racemic mixture in these beer samples. The racemization of IX in beer could be attributed to the production of a racemic mixture from XN during boiling and to the fact that IX enantiomers were easily interconverted. 相似文献
105.
ABSTRACT Barley has two flowering types, chasmogamous (open-flowering) and cleistogamous (closed-flowering). We examined the effect of the timing of Fusarium graminearum infection on Fusarium head blight (FHB) and mycotoxin accumulation in barley cultivars with different flowering types using greenhouse experiments. In the first experiment, 13 cultivars were spray inoculated at two different developmental stages, and the severity of FHB was evaluated. The effect of the timing of infection differed among cultivars. Cleistogamous cultivars were resistant at anthesis but susceptible at 10 days after anthesis, whereas chasmogamous cultivars were already susceptible at anthesis. In the second experiment, five cultivars were inoculated at three different developmental stages and the concentrations of deoxynivalenol (DON) and nivalenol (NIV) in mature grain were analyzed. Cleistogamous cultivars accumulated more mycotoxins (DON and NIV) when inoculated 10 or 20 days after anthesis than when inoculated at anthesis, whereas chasmogamous cultivars accumulated more mycotoxins when inoculated at anthesis. Thus, the most critical time for F. graminearum infection and mycotoxin accumulation in barley differs with cultivar, and likely is associated with the flowering type. Late infection, even without accompanied FHB symptoms, was also significant in terms of the risk of mycotoxin contamination. 相似文献
106.
Noboru KUDO Chieko OTA Fumiko SAKA Yae IKEDA Yusuke TOMIHISA Yasunaga ITOI Takashi OYAMADA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(12):1651-1654
Seven laboratory mammal and
bird species were orally inoculated with 200–1,000 encysted Metagonimus
hakubaensis metacercariae that had been isolated from naturally infected
lampreys (Lethenteron reissneri) captured in Aomori Prefecture. At 8 and
15 days post-infection, adult flukes were recovered from all of the laboratory animals
tested, and therefore, hamster, rat, mouse, dog, cat, chicken and quail were considered as
final hosts of M. hakubaensis. Recovery rates of the fluke were higher in
dogs and hamsters than in cats, rats, mice, chickens and quails. The flukes recovered from
dogs and hamsters showed increased body length and higher fecundity than those recovered
from the other hosts. These results indicate that the suitability of dogs and hamsters for
M. hakubaensis infection is higher than that of the other laboratory
animals. 相似文献
107.
108.
109.
110.
Kei ISHII Mito KANATSU-SHINOHARA Takashi SHINOHARA 《The Journal of reproduction and development》2014,60(1):37-46
Spermatogonial stem cells (SSCs) migrate to the niche upon introduction into the
seminiferous tubules of the testis of infertile animals. However, only 5–10% of the
transplanted cells colonize recipient testes. In this study, we analyzed the impact of
cell cycle on spermatogonial transplantation. We used fluorescent ubiquitination-based
cell cycle indicator transgenic mice to examine the influence of cell cycle on SSC
activity of mouse germline stem (GS) cells, a population of cultured spermatogonia
enriched for SSCs. GS cells in the G1 phase are more efficient than those in the S/G2-M
phase in colonizing the seminiferous tubules of adult mice. Cells in the G1 phase not only
showed higher expression levels of GFRA1, a component of the GDNF self-renewal factor
receptor, but also adhered more efficiently to laminin-coated plates. Furthermore, this
cell cycle-dependency was not observed when cells were transplanted into immature pup
recipients, which do not have the blood-testis barrier (BTB) between Sertoli cells,
suggesting that cells in the G1 phase may passage through the BTB more readily than cells
in the S/G2-M phase. Thus cell cycle status is an important factor in regulating SSC
migration to the niche. 相似文献