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排序方式: 共有395条查询结果,搜索用时 31 毫秒
21.
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
22.
S Ishikawa R Machida K Hiraga Y Hiradate Y Suda K Tanemura 《Reproduction in domestic animals》2014,49(2):e26-e30
We analysed the effect of three antioxidants that have different functional mechanisms on the in vitro maturation (IVM) of porcine oocytes. Single oocyte monoculture using the hanging drop (HD) system has some advantages such as improving analysis efficiency brought by the smaller number of samples than the number of oocytes cultured in one drop. Direct effects of ligands on single oocytes could also be detected without considering the effects of paracrine factors from other oocytes. After 22 h of pre‐culture, denuded oocytes were cultured for 22 h with 0.01 and 0.1 μg/ml of L‐carnitine (LC), lactoferrin (LF) or sulforaphane (SF) in the presence/non‐presence of oxidant stress induced by H2O2 supplementation to evaluate the reducing effects against oxidative stress on nuclear maturation. As a result, compared with LC and SF, LF showed effective reduction in oxidative stress at a lower concentration (0.01 μg/ml), suggesting that LF is a more effective antioxidant in porcine oocyte IVM. Additionally, LF also increased maturation rate even in culture without H2O2. Our results clearly suggest that the HD monoculture system is useful for screening the substances that affect porcine oocyte culture. 相似文献
23.
24.
Shin-Ichi Teshima Shunsuke Koshio Manabu Ishikawa Md. Shah Alam Luis Hector Hernandez Hernandez 《Journal of the World Aquaculture Society》2006,37(2):145-153
The dietary protein requirement of the freshwater prawn Macrobrachium rosenbergii to obtain the maximum body protein retention was assessed by the estimated protein needed daily for maintenance (M) and body protein increment (G). The body protein increment was estimated by quantifying body nitrogen increments when the prawn was fed high‐protein diets composed primarily of casein. The protein required for maintenance was estimated by regressing weight gains in feeding experiments using graded dietary levels of casein. The true daily retention (R) or increase in body protein of the prawn corresponds to the sum of M and G. The values of M, G, and R determined in the present study were 3.86, 0.24, and 4.10 g/kg body weight/d, respectively. On the basis of the daily body protein increment and the net protein utilization of casein (58%), dietary protein requirement of the juvenile M. rosenbergii for maximum body protein retention was suggested to be about 7.1 g/kg body weight/d. 相似文献
25.
T. Tokumoto M. Tokumoto M. Ishimatsu R. Horiguchi Y. Nagahama K. Ishikawa 《Fish physiology and biochemistry》2003,28(1-4):371-371
Destruction of cyclin B is required for exit from mitosis and meiosis. A cyclin-specific ubiquitinating system, including anaphase-promoting complex/cyclosome (APC/C) is thought to be responsible for cyclin B destruction. To learn more about the molecular mechanism of cyclin B degradation, a molecular study of the ubiquitinating system in goldfish has been undertaken. For biochemical preparation of APC/C, we first conducted the cloning, sequencing and expression analysis of goldfish, Carassius auratus, cdc27 that encodes a subunit of APC/C from goldfish ovary. The deduced amino acid sequence is highly homologous to cdc27 from other species. Then recombinant goldfish Cdc27CT (C-terminal half of Cdc27) was expressed in Escherichia coli, and an antibody was raised against purified recombinant protein. Polyclonal antiserum cross-reactive with Cdc27 was obtained. By the assay using the antibody, APC/C was purified by column chromatographs. 相似文献
26.
Summary Mitochondrial DNA (mtDNA) diversity has been determined in apple landraces and cultivars, based upon restriction fragment length polymorphisms (RFLPs) for several mitochondrial genes. Our analysis includes three cultivars, Golden Delicious, McIntosh and Delicious, which represent the various patterns of mtDNA polymorphisms previously described (Ishikawa et al., 1992). A total of five RFLPs were detected, allowing classification of the apple genotypes into four cytoplasmic groups: GroupI, Golden Delicious-type; GroupII, McIntosh-type; GroupIII, Delicious-type; and Group IV, Dolgo Crab-type. European landraces and cultivars were assigned to Groups I, II, and III, while chinese crab apples were placed in either Group III or IV. 相似文献
27.
Chhourn Orn Rieko Shishido Masahiro Akimoto Ryo Ishikawa Than Myint Htun Ken-Ichi Nonomura Yohei Koide Men Sarom Seng Vang Sakhan Sophany Ouk Makara Takashige Ishii 《Breeding Science》2015,65(5):430-437
A total of 448 samples in five natural populations of wild rice (Oryza rufipogon) were collected in Cambodia. They were examined using 12 SSR and two chloroplast markers to evaluate the degree of variation among populations and the genetic structure within populations. In the two annual populations, the number of plants with homozygous alleles at all 12 SSR loci were high (66.3% and 79.5%), suggesting that these plants propagate mainly through self-pollination. In the three perennial populations, no individuals had all homozygous genotypes, but redundant genotypes resulted from clonal propagation were observed. Percentages of the redundant genotypes were highly varied (3.6%, 29.2% and 86.0%). This may be due to the different stable levels of environmental conditions. As for chloroplast genome, most of the wild plants showed the same chloroplast types as most Indica-type cultivars have. However, plants with different chloroplast types were maintained, even in the same population. In tropical Asian countries, many wild rice populations were observed under similar ecological conditions examined in this study. Therefore, the present results concerning population structure will be important to further elucidate genetic features of wild rice, and will also give strong clues to utilize and conserve wild natural genetic resources. 相似文献
28.
Zhi-Shan Lin Zhi-Fu Cui Xiang-Yan Zeng You-Zhi Ma Zeng-Yan Zhang Toshiki Nakamura Goro Ishikawa Kazuhiro Nakamura Hisashi Yoshida Zhi-Yong Xin 《Euphytica》2007,158(1-2):109-118
Chromosome compositions of seven lines, derived from hybrids between a wheat cultivar and the wheat-Thinopyrum intermedium addition line Z6, with barley yellow dwarf virus (BYDV) resistance, were determined by genomic in situ hybridization, cytogenetic and SSR assays. The results showed that
line N522 was a disomic addition line, lines N420 and N439 were 2Ai-2(2B) chromosome substitution lines, lines N431 and N452
were 2Ai-2(2D) chromosome substitution lines, line N523 was a 2Ai-2S(2D) ditelosomic substitution line, and line N530 was
a double ditelosomic line with the mitotic chromosome number of 2n = 40 + 4t. One pair of telosomes in line N530 lacked several proximal SSR markers of chromosome 2AS, but possessed certain
terminal markers, which were consistent with an acrocentric structure, and the other pair of chromosome arms were presumably
2Ai-2S telosomes with BYDV-resistance. These wheat-Th. intermedium lines provide useful genetic resources for developing alien chromosome translocation lines. 相似文献
29.
Three apple (Malus×domestica) cultivars and 11 Malus accessions have been investigated by the probe hybridization method on their mitochondrial DNA (mtDNA). The gene probes used were: coxI, coxII, atpA, atp6, and atp9. Our results revealed enough variation to characterize ten mtDNA haplotypes among the Malus genotypes examined. The taxonomic and phylogenetic implications of mtDNA polymorphism are also discussed. 相似文献
30.
Tian-Xiao Meng Shoko Furuta Sayaka Fukamizu Ryoko Yamamoto Hiroya Ishikawa Enos Tangke Arung Kuniyoshi Shimizu Shoji Ohga Ryuichiro Kondo 《Journal of Wood Science》2011,57(5):452-458
Pleurotus citrinopileatus Singer has recently become a popular delicacy in East Asian countries. We prepared a methanol extract, soluble fractions
from the methanol extract, and a hot water extract of the fruiting bodies of P. citrinopileatus. The biological activities such as melanin biosynthesis inhibition, tyrosinase inhibition, antioxidant activities [1,1-diphenyl-2-picrylhydrazyl
(DPPH) radical scavenging, oxygen radical absorbance capacity (ORAC), and superoxide dismutase (SOD)-like activity], antibacterial
activities, and antihyaluronidase activities of these extracts were evaluated. We found that the n-hexanesoluble, diethyl ether-soluble, and ethyl acetate-soluble fractions exhibited melanin biosynthesis inhibition in B16
melanoma cells, as well as antioxidant (ORAC) and antibacterial activities. However, the n-butanol-soluble and water-soluble fractions and the methanol and hot water extracts exhibited antioxidant (DPPH radical scavenging,
SOD-like activity) and antihyaluronidase activities. These results indicate that the fruiting bodies of P. citrinopileatus have the potential to be used as an ingredient in skin cosmetics. 相似文献