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921.
922.
Vibrational circular dichroism (VCD) spectra were obtained for the assignments of the absolute configurations of diastereomeric 4,7-bis(methoxycarbonyl)-12,15-dimethoxy-[2.2]paracyclophanes (1 and 2), and density functional theory (DFT) calculations were performed at the B3LYP/6-31G(d) level for all possible conformations of both 1 and 2 to give the theoretical VCD spectra. Comparisons of the experimental and theoretical VCD spectra obtained unambiguously established the absolute configurations of the dextrorotatory (+)-enantiomers as (4S(p);12S(p))-1 and (4S(p);12R(p))-2, respectively. 相似文献
923.
Changes in soybean phytate content as a result of field growing conditions and influence on tofu texture 总被引:2,自引:0,他引:2
Ishiguro T Ono T Wada T Tsukamoto C Kono Y 《Bioscience, biotechnology, and biochemistry》2006,70(4):874-880
It is known that tofu quality tends to vary among soybeans even of the same variety. Cultivation environments can affect the contents of the soybeans. Twenty-seven soybean varieties were grown in a drained paddy field and an upland field, and then their protein and phytate contents were determined using the Fourier transfer infrared spectroscopy (FT-IR) method. The phytate contents of 12 varieties were higher in the drained paddy field than in the upland field. On the other hand, the environmental factor had little effect on the protein contents. In order to determine whether the difference in phytate content affected tofu texture, the hardness of the tofu made from phytate-added soymilk was measured. The tofu texture having more phytate became softer in the range of the common coagulant concentration. We concluded that the difference in the phytate content of the soybeans among the environmental conditions is a factor that causes fluctuation in tofu quality. 相似文献
924.
Effects of storage temperature on the contents of sugars and free amino acids in tubers from different potato cultivars and acrylamide in chips 总被引:1,自引:0,他引:1
Matsuura-Endo C Ohara-Takada A Chuda Y Ono H Yada H Yoshida M Kobayashi A Tsuda S Takigawa S Noda T Yamauchi H Mori M 《Bioscience, biotechnology, and biochemistry》2006,70(5):1173-1180
To clarify the effects of storage temperature on potato components and acrylamide in chips, tubers from five cultivars were stored at various temperatures (2, 6, 8, 10, and 18 degrees C) for 18 weeks, and the contents of sugars, free amino acids in tubers, and acrylamide in chips after frying were analyzed. At temperatures lower than 8 degrees C, the contents of reducing sugars increased markedly in all cultivars, with similar increases in the acrylamide level and dark brown chip color. Free amino acids showed little change at the storage temperatures tested and varied within certain ranges characteristic of each cultivar. The contents of reducing sugars correlated well with the acrylamide level when the fructose/asparagine molar ratio in the tubers was <2. When the fructose/asparagine ratio was >2 by low-temperature storage, the asparagine content, rather than the reducing sugar content, was found to be the limiting factor for acrylamide formation. 相似文献
925.
926.
Ito H Yuto S Motoi H Yagishita T Takeya K Sugiyama K Kiriyama S Morita T 《Bioscience, biotechnology, and biochemistry》2006,70(10):2429-2436
We examined in rats whether or not the prolonged ingestion of recrystallized amylose (RCA) would prevent the development of insulin resistance. Rats were fed on a diet containing waxy cornstarch (WCS) as carbohydrate or a diet containing 30% RCA in place of WCS for 18 wk. Glucose tolerance test (GTT) was conducted at every four weeks. On wk 16, the plasma insulin response as assessed by the area under the curve was lower in the RCA diet group than in the WCS diet group. The fasting plasma insulin level tended to increase over time in both groups, but was lower in the RCA diet group on wk 16. An autopsy revealed that the adipose tissue mass and serum free fatty acid concentrations were significantly higher in the WCS diet group. The results suggest that prolonged ingestion of RCA had the effect of slowing the development of insulin resistance through a lower concentration of serum free fatty acids, presumably due to the prevention of adipocyte hypertrophy. 相似文献
927.
928.
Ohyama T Mohamed OA Taketo MM Dufort D Groves AK 《Development (Cambridge, England)》2006,133(5):865-875
929.
Shinozuka T Shimada K Matsui S Yamane T Ama M Fukuda T Taki M Naito S 《Bioorganic & medicinal chemistry letters》2006,16(6):1502-1505
We have designed and synthesized a novel series of 3-biphenylamino acid amides as cathepsin K inhibitors based on compound I. In these inhibitors, we have discovered 4-aminophenoxyacetic acids 43 and 47 with good IC(50) values, although lipophilic groups are favorable for the hydrophobic S1' pocket. 相似文献
930.
Takahiro Yamagishi Taizo Motomura Chikako Nagasato Hiroshi Kawai 《Journal of phycology》2009,45(5):1110-1115
Two‐dimensional (2‐D) protein analysis of the mastigoneme fraction of the chromophyte alga Ochromonas danica E. G. Pringsh. showed the presence of several component proteins of the tubular mastigoneme. Adding to the reported gene Ocm1, three new genes (Ocm2, Ocm3, and Ocm4) belonging to the Ocm gene family were isolated using degenerate primers designed from predicted Ocm1 amino acid sequences. The predicted polypeptides encoded by Ocm2, Ocm3, and Ocm4 were smaller in size than Ocm1. However, they shared four highly conserved, cysteine‐rich, epithelial growth factor (EGF)‐like motifs, potentially involved in protein–protein interaction. In addition, Ocm2, Ocm3, and Ocm4 showed homology to the SIG protein family in the centric diatom Thalassiosira weissflogii (Grunow) Fryxell et Hasle, which is up‐regulated during early stages of sexual reproduction. Immunofluorescence analysis with a polyclonal antibody against the partial amino acid sequences of Ocm2, Ocm3, and Ocm4 showed that Ocm2 and Ocm3 were located in the basal segment region of mastigonemes attached on the surface of the anterior flagellum, and that Ocm4 was located within the tubular shaft portion similar to Ocm1. 相似文献