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961.
In a previous paper it has been described that α-amylase formation in Aspergillus oryzae is stimulated by soluble starch, glycogen and maltose, whereas it is inhibited by glucose, which is added into a growing medium or a secondary incubation medium as the carbon source. The present paper reports that isomaltose and panose are the most effective inducers among a large number of sugars examined here, and suggests the importance of transglucosidase action demonstrated in view of α-amylase formation. The initial action of inducers in this system is also discussed.  相似文献   
962.
During the course of investigation on organophosphorus insecticides, many organophosphorus compounds having methyl-, methyl-chloro-, methyl-nitro-, methyl-cyano-, methyl-thiocyano-, methoxy-nitro-, acyloxy-nitro-, and chloro-cyano-phenyl groups were prepared and their biological activities tested. As the results of these studies, two compounds were found as new low toxic organophosphorus insecticides, namely, O,O-dimethyl-O- (3-methyl-4-nitro-phenyl) and O,O-dimethyl-O- (4-cyanophenyl) phosphorothioates.  相似文献   
963.
Effects of pH and some chemical agents (1) on the solubilization of insoluble pectin bound to suspended particles, (2) on the viscosity decrease of native soluble pectin, (3) on the flocculation of suspended particles and (4) on the over-all clarification of apple juice have been studied Optimum pH ranges were: (1), 3.2~4.0; (2), 3.6~4.1; (3), lower than 3.0; (4), 3.2~3.8. Gelatin had no effect on (1) and (2) but stimulated (3) and (4). NaCl had no detectable effect on (2) and (3) but slightly stimulated (1) and (4). CaCl2 strongly inhibited (1), (2) and (3). SnCl4 stimulated (3) but strongly inhibited (1), (2) and (4). EDTA (ethylenediamineteraacetic acid) accelerated (1) and (4), and had no detectable effect on (2) and (3).  相似文献   
964.
It is well known that biotin has a marked effect on l-glutamic acid fermentation.

The authors have intended to find strains which are independent of the amounts of biotin in the culture medium. As a result, oleic acid-requiring mutants were obtained from a strain of Brevibacterium thiogenitalis which is an auxotroph for biotin. The growth of the mutant was remarkably stimulated by Tween 20, 40, 60, Ca ions and a small amount of corn steep liquor. And also, the mutant was found to have lost its requirement for biotin and showed growth response only to oleic acid or unsaturated fatty acids.

The effect of biotin, oleic acid and other unsaturated fatty acids on the production of l-glutamic acid was investigated by using an oleic acid-requiring mutant of Brevibacterium thiogenitalis No. 653. The results described in the present paper showed that the oleic acid-requiring mutant D-248 produced a large amount of l-glutamic acid in the excess biotin-contaming media, and that oleic acid seemed to be completely replaced by other unsaturated fatty acids such as palmitoleic acid and linoleic acid.  相似文献   
965.
Basic flavor components were isolated from various types of miso and determined qualitatively and quantitatively by gas chromatography and mass spectrometry. 12 pyrazines, 3 pyridines, N-methylpyrrolidone, 2-acethylpyrrole and benzothiazole were identified. All but tetramethylpyrazine had not been reported previously for their presence in miso. Concentrations of the basic components, except for pyridines, varied considerably, depending on the type of miso. The factors which influenced the levels of these components were primarily a soy bean cooking condition and a koji ratio. The flavor contribution of alkylpyrazines to each type of miso is also discussed on the basis of the additivity of odorous mixture. Alkylpyrazines were judged to contribute to miso flavor, particularly in the soy bean miso.  相似文献   
966.
An alkalophilic bacterium, strain No. 150–1, which had NAD-dependent sugar dehydrogenase activities on maltose (NAD-MalDH) and d-glucose (NAD-GlcDH), was isolated from soil. This microorganism was identificd to be in a strain of the genus Corynebacterium. The bacterium grew to similar degrees at Na2CO3 concentrations from 0 to 0.5%. NAD-MalDH and NAD-GlcDH were not inducible types. Soybean casein was the most effective nitrogen source for enzyme production. Activity staining of these two dehydrogense on polyacrylamide gel showed that these activities were derived from two different proteins. The cell free extract did not contain NADP-dependent maltose dehydrogenase.  相似文献   
967.
A variety of 6-substituted-3-pyridazinyl phosphorothioates were synthesized by the reaction of O,O-dialkyl phosphorothiochloridates with corresponding 3 (2H)pyridazinones. In certain cases, N-alkylated pyridazinones were formed along with the desired phosphorothioates. The optimal condition for the phosphorylation and the mechanism of the N-alkylation were investigated.  相似文献   
968.
This paper describes the synthesis and biological evaluation of styrylbenzimidazole (SBIM) derivatives as agents for imaging neurofibrillary tangles (NFT) in patients with Alzheimer’s disease (AD). SBIM derivatives were prepared with 4-iodobenzene-1,2-diamine and substituted cinnamaldehydes. In binding experiments using recombinant tau and Aβ1–42 aggregates, SBIM-3 showed higher affinity for the tau aggregates than Aβ1–42 aggregates (ratio of Kd values was 2.73). In in vitro autoradiography and fluorescent staining, [125I]SBIM-3 (or SBIM-3) bound NFT in sections of AD brain tissue. In biodistribution experiments using normal mice, all [125I]SBIM derivatives showed high initial uptake into (3.20–4.11%ID/g at 2 min after the injection) and rapid clearance from (0.12–0.33%ID/g at 60 min after the injection) the brain. In conclusion, appropriate structural modifications of SBIM derivatives could lead to more useful agents for the in vivo imaging of NFT in AD brains.  相似文献   
969.
The prevalence of obesity is increasing globally, and obesity is a major risk factor for type 2 diabetes and cardiovascular disease. We investigated the effects of coffee polyphenols (CPP), which are abundant in coffee and consumed worldwide, on diet-induced body fat accumulation. C57BL/6J mice were fed either a control diet, a high-fat diet, or a high-fat diet supplemented with 0.5 to 1.0% CPP for 2-15 wk. Supplementation with CPP significantly reduced body weight gain, abdominal and liver fat accumulation, and infiltration of macrophages into adipose tissues. Energy expenditure evaluated by indirect calorimetry was significantly increased in CPP-fed mice. The mRNA levels of sterol regulatory element-binding protein (SREBP)-1c, acetyl-CoA carboxylase-1 and -2, stearoyl-CoA desaturase-1, and pyruvate dehydrogenase kinase-4 in the liver were significantly lower in CPP-fed mice than in high-fat control mice. Similarly, CPP suppressed the expression of these molecules in Hepa 1-6 cells, concomitant with an increase in microRNA-122. Structure-activity relationship studies of nine quinic acid derivatives isolated from CPP in Hepa 1-6 cells suggested that mono- or di-caffeoyl quinic acids (CQA) are active substances in the beneficial effects of CPP. Furthermore, CPP and 5-CQA decreased the nuclear active form of SREBP-1, acetyl-CoA carboxylase activity, and cellular malonyl-CoA levels. These findings indicate that CPP enhances energy metabolism and reduces lipogenesis by downregulating SREBP-1c and related molecules, which leads to the suppression of body fat accumulation.  相似文献   
970.
Angiogenesis plays an important role in the progression of astrocytic tumors and its evaluation is a major prognostic factor. Although the form of proliferating vessels ranges from fine capillaries to well-developed vascular structures with a smooth muscle layer, the characteristics of vascular smooth muscle cells (SMCs) are not understood in detail. We therefore examined the density, size and shape of tumor vessels, as well as CD34-immunoreactive (CD34-Vs) or α-smooth muscle actin-immunoreactive (SMA-Vs) vessels in 46 primary astrocytomas (grade II diffuse astrocytomas, n=11, grade III anaplastic astrocytomas, n=15, grade IV glioblastomas, n=20) and in normal brain tissues from 10 autopsies. We also examined the expression of high molecular weight caldesmon (h-CD, a marker of the contractile phenotype of smooth muscle) and of platelet-derived growth factor receptor β (PDGFR-β). The SMA-Vs were significantly more dense and larger in grade IV than grade III, whereas those of CD34-Vs did not differ between grade III and IV. Changes in the shape of CD34-Vs and SMA-Vs correlated with histological grading. The expression of h-CD was reduced, whereas that of PFGFR-β was increased in high grade-astrocytomas. Kaplan-Meier analysis indicated that the density of SMA-Vs, the size of both CD34 and SMA-Vs and PDGFR-β expression were significant prognostic factors. These findings suggest that SMA-Vs are significantly associated with the progression of astrocytomas and that these vessels provide useful information for the histological diagnosis and survival of patients with these types of brain tumors.  相似文献   
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