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91.
Phenylalanine ammonia-lyase, trans-cinnamate 4-monooxygenase, and capsaicinoid synthetase [Agric. Biol. Chem., 44, 2907 (1980)] activities were investigated in the subcellular fractions from protoplasts of placenta of Capsicum fruits. The subcellular distribution of intermediates of the capsaicinoid biosynthesis, trans-cinnamic acid and trans-p-coumaric acid, and capsaicinoid were also investigated. The activity of trans-cinnamate 4-monooxygenase and capsaicinoid synthetase was in the vacuole fraction. While the activity of phenylalanine ammonia-lyase was in the cytosol fraction. After feeding l-[U-14C]phenylalanine to the protoplast, the newly synthesized trans-p-coumaric acid and capsaicinoid were found in the vacuole fraction, while trans-cinnamic acid was not in the vacuole fraction. The possible role of the vacuole on the biosynthesis of capsaicinoid is also discussed.  相似文献   
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Guanosine triphosphate cyclohydrolase (EC 3.5.4.16) was previously shown to exist in two forms (GTP cyclohydrolase D-I and D-II) in Serratia indica IFO 3759, and they were homogeneously isolated. The present study deals with the characterization of their reaction products. A fluorescent product formed from guanosine triphosphate by GTP cyclohydrolase D-II was identified as 7,8-dihydroneopterin triphosphate by its absorption spectra, phosphate analysis and gas chromatography-mass spectrometry of the dephosphorylated trimethylsilyl derivative. After oxidation and dephosphorylation, the d-erythro configuration of the side chain was made clear by the elution profile on ECTEOLA-cellulose chromatography, Rf values on thin-layer chromatography and by biological activity to Crithidia fasciculata ATCC 12857. The fluorescent products from GTP cyclohydrolase D-I and D-II were indistinguishable.  相似文献   
94.
Previous structural studies of less-polar dimers in autoxidized methyl linoleate (ML) have been extended to polar dimers. After isolation by successive silicic acid and gel permeation chromatography, the dimeric fraction of linoleate was separated into two major fractions, A1 and A2, according to their polarities. The polar dimers (A1) were further fractionated by HPLC either directly or after reduction with triphenyl phosphine on a micro silica column. Isolated subfractions were characterized by UV, IR, GC-MS and FD-MS after suitable derivatizations. FD-MS of all these dimers showed a molecular ion peak which corresponds to 2 × ML + 6 × O and the reduction of each subfraction with stannous chloride gave equimolar amounts of 9 and 13-hydroxy octadecadienoate, and 9, 10, 13 and/or 9, 12, 13-trihydroxy octadecenoate. These results combined with others show that the A1 dimers are composed of isomeric mixtures containing a peroxide bridge linking a methyl octadecadienoate and a 9, 12 and/or 10, 13-dihydroperoxy octadecenoate across C-9 and/or 13 on each of them.  相似文献   
95.
Pungent principles (Capsaicinoid(s)) were found to be produced in fruits of sweet pepper, Capsicum annuum L. var. grossum, during post-harvest ripening under continuous light. The initial formation was observed after 4 days’ ripening. After 7 days’ ripening, the capsaicinoids content in placenta increased to 12.9 μg per fruit, which was 2.5-fold of that in pericarp. No pungent principles were detected in fruits during ripening in the dark and in seeds under continuous light. In placenta, the formation of dihydrocapsaicin and nordihydrocapsaicin which are the vanillylamides of saturated branched fatty acids was higher than that of capsaicin which is the vanillylamide of an unsaturated one. Remarkable formation and accumulation of carotenoid were also observed during post-harvest ripening under continuous light.  相似文献   
96.
Taxonomic and some other properties of a yeast strain, Candida sp. 36, which characteristically assimilates n-alkanes, were described. Identification of coenzyme Q, NMR spectroscopy of cell wall polysaccharides, determination of G+C content of DNA and some DNA-DNA hybridization experiments were carried out, in addition to the morphological and physiological observations. All the data were consistent with the suggestion that Candida cloacae Komagata, Nakase and Katsuya and Candida subtropicalis Nakase, Fukazawa and Tsuchiya are the synonyms of Candida maltosa Komagata, Nakase and Katsuya. Candida sp. 36 was identified as C. maltosa, too. The yeast was found to grow most abundantly on n-hexadecane and on n-octadecane in the presence of biotin.  相似文献   
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ABSTRACT

Bilberry has been reported to have anti-oxidant and anti-inflammatory properties. We studied the effect of bilberry (Vaccinium myrtillus L.) fruits extracts (BEs) on the pathogenesis caused by lipid accumulation in fatty liver and non-alcoholic steatohepatitis (NASH). 5 μg/ml of BEs was enough to suppress lipid accumulation in the fatty liver model of the mouse hepatic AML12 cells. BEs increased cell viability and anti-oxidant capacity, presumably by activating (phosphorylating) Akt/STAT3 and inducing MnSOD/catalase. BEs also significantly reduced Rubicon and induced p62/SQSTM1, possibly contributing to reduce cellular lipids (lipophagy). When the mice were fed supplemented with BEs (5% or 10%, w/w), hepatic steatosis, injury, and hypercholesterolemia/hyperglycemia were significantly improved. Furthermore, histological and cytokine studies indicated that BEs possibly suppress hepatic inflammation (hepatitis) and fibrosis. Therefore, BEs improved liver steatosis and injury, and potentially suppress fibrosis by suppressing inflammatory response, which therefore may prevent the progression of fatty liver to NASH.  相似文献   
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BackgroundAlthough several computer-aided computed tomography (CT) analysis methods have been reported to objectively assess the disease severity and progression of idiopathic pulmonary fibrosis (IPF), it is unclear which method is most practical. A universal severity classification system has not yet been adopted for IPF.ObjectiveThe purpose of this study was to test the correlation between quantitative-CT indices and lung physiology variables and to determine the ability of such indices to predict disease severity in IPF.MethodsA total of 27 IPF patients showing radiological UIP pattern on high-resolution (HR) CT were retrospectively enrolled. Staging of IPF was performed according to two classification systems: the Japanese and GAP (gender, age, and physiology) staging systems. CT images were assessed using a commercially available CT imaging analysis workstation, and the whole-lung mean CT value (MCT), the normally attenuated lung volume as defined from −950 HU to −701 Hounsfield unit (NL), the volume of the whole lung (WL), and the percentage of NL to WL (NL%), were calculated.ResultsCT indices (MCT, WL, and NL) closely correlated with lung physiology variables. Among them, NL strongly correlated with forced vital capacity (FVC) (r = 0.92, P <0.0001). NL% showed a large area under the receiver operating characteristic curve for detecting patients in the moderate or advanced stages of IPF. Multivariable logistic regression analyses showed that NL% is significantly more useful than the percentages of predicted FVC and predicted diffusing capacity of the lungs for carbon monoxide (Japanese stage II/III/IV [odds ratio, 0.73; 95% confidence intervals (CI), 0.48 to 0.92; P < 0.01]; III/IV [odds ratio. 0.80; 95% CI 0.59 to 0.96; P < 0.01]; GAP stage II/III [odds ratio, 0.79; 95% CI, 0.56 to 0.97; P < 0.05]).ConclusionThe measurement of NL% by threshold-based volumetric CT analysis may help improve IPF staging.  相似文献   
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