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Nuttha Thongchul Surapong Navankasattusas Shang-Tian Yang 《Bioprocess and biosystems engineering》2010,33(3):407-416
Cassava pulp was hydrolyzed with acids or enzymes. A high glucose concentration (>100 g/L) was obtained from the hydrolysis
with 1 N HCl at 121 °C, 15 min or with cellulase and amylases. While a high glucose yield (>0.85 g/g dry pulp) was obtained
from the hydrolysis with HCl, enzymatic hydrolysis yielded only 0.4 g glucose/g dry pulp. These hydrolysates were used as
the carbon source in fermentation by Rhizopus oryzae NRRL395. R. oryzae could not grow in media containing the hydrolysates treated with 1.5 N H2SO4 or 2 N H3PO4, but no significant growth inhibition was found with the hydrolysates from HCl (1 N) and enzyme treatments. Higher ethanol
yield and productivity were observed from fermentation with the hydrolysates when compared with those from fermentation with
glucose in which lactic acid was the main product. This was because the extra organic nitrogen in the hydrolysates promoted
cell growth and ethanol production. 相似文献
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NTAL (non-T cell activation linker)/LAB (linker for activation of B cells) is a LAT (linker for activation of T cells)-like molecule that is expressed in B cells, mast cells, natural killer cells, and monocytes. Upon engagement of the B cell receptor or Fc receptors, it is phosphorylated and interacts with Grb2. LAB is capable of rescuing thymocyte development in LAT(-/-) mice. In this study, we utilized various LAB Tyr to Phe mutants to map the phosphorylation and Grb2-binding sites of LAB. We also examined the function of these mutants by investigating their ability to rescue signaling defects in LAT-deficient Jurkat cells and thymocyte development in LAT(-/-) mice. Our results indicated that human LAB was primarily phosphorylated on three membrane-distal tyrosines, Tyr(136), Tyr(193), and Tyr(233). Mutation of these three tyrosines abolished Grb2 binding and LAB function. Our data suggested that these tyrosines are the most important tyrosines for LAB function. 相似文献
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Porntep Chomcheon Suthep Wiyakrutta Nattaya Ngamrojanavanich Surapong Kengtong Somsak Ruchirawat Prasat Kittakoop 《Phytochemistry》2009,70(3):407-413
Isolation of a broth extract of the endophytic fungus Corynespora cassiicola L36 afforded three compounds, corynesidones A (1) and B (3), and corynether A (5), together with a known diaryl ether 7. Compounds 1, 3, 5, and 7 were relatively non-toxic against cancer cells, and inactive toward normal cell line, MRC-5. Corynesidone B (3) exhibited potent radical scavenging activity in the DPPH assay, whose activity was comparable to ascorbic acid. Based on the ORAC assay, compounds 1, 3, 5, and 7 showed potent antioxidant activity. However, the isolated natural substances and their methylated derivatives (1−8) neither inhibited superoxide anion radical formation in the XXO assay nor suppressed TPA-induced superoxide anion generation in HL-60 cell line. Corynesidone A (1) inhibited aromatase activity with an IC50 value of 5.30 μM. 相似文献
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Gonzalez MJ Pinto MM Kijjoa A Kengthong S Mondanondra IO Silva AM Eaton G Herz W 《Phytochemistry》2002,61(8):995-998
Wood of Horsfieldia irya contained 2-n-nonyl- and 2-(6-phenylhexyl)-5,7-dihydroxychromone, 2-n-nonyl-8-hydroxy- and 2-(6-phenylhexyl)-8-hydroxy-5,6,7,8-tetrahydrochromone as well as dihydrocubebin. 相似文献
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The purpose of this study was to investigate how plasma viscosity affects cardiac and vascular function during moderate hemodilution. Twelve anesthetized hamsters were hemodiluted by 40% of blood volume with two different viscosity plasma expanders. Experimental groups were based on the plasma expander viscosity, namely: high viscosity plasma expander (HVPE, 6.3 mPa?·?s) and low viscosity plasma expander (LVPE, 2.2 mPa?·?s). Left ventricular (LV) function was intracardiacally measured with a high temporal resolution miniaturized conductance catheter and concurrent pressure-volume results were used to calculate different LV indices. Independently of the plasma expander, hemodilution decreased hematocrit to 28% in both groups. LVPE hemodilution reduced whole blood viscosity by 40% without changing plasma viscosity, while HVPE hemodilution reduced whole blood viscosity by 23% and almost doubled plasma viscosity relative to baseline. High viscosity plasma expander hemodilution significantly increased cardiac output, stroke volume and stroke work compared to baseline, whereas LVPE hemodilution did not. Furthermore, an increase in plasma viscosity during moderate hemodilution produced a higher energy transfer per unit volume of ejected blood. Systemic vascular resistance decreased after hemodilution in both groups. Counter-intuitively, HVPE hemodilution showed lower vascular resistance and vascular hindrance than LVPE hemodilution. This result suggests that geometrical changes in the circulatory system are induced by the increase in plasma viscosity. In conclusion, an increase in plasma viscosity after moderate hemodilution directly influenced cardiac and vascular function by maintaining hydraulic power and reducing systemic vascular resistance through vasodilation. 相似文献
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AimsThis study evaluated the hypothesis that exogenous nitric oxide (NO) supplementation during acute hemodilution with plasma expander (PE) provides beneficial effects on cardiac function.Main methodsAcute hemodilution in golden Syrian hamsters was induced by a 40% of blood volume exchange with dextran 70 kDa. Intravascular NO supplementation after hemodilution was accomplished with a NO donor, diethylenetriamine NONOate (DETA NONOate). The test group was treated with DETA NONOate, while the control group received only vehicle. Left ventricular cardiac function was studied using pressure–volume measurements obtained with a miniaturized conductance catheter.Key findingsCardiac output increased to 122 ± 5% and 107 ± 1% of the baseline in the group treated with NO donor and the vehicle group, respectively. Stroke work per stroke volume (SW/SV) after hemodilution reduced to 90% of the baseline and the NO donor significantly reduced SW/SV compared to the vehicle. The minimum rate of pressure change (dP/dtmin) was significantly lower in animals treated with the NO donor compared to vehicle treated animals. Systemic vascular resistance (SVR) decreased to 62 ± 5% of the baseline in the NO donor group whereas the vehicle group SVR decreased to 83 ± 5% of the baseline. Using intravital microscopy analysis of microvessel in the dorsal skinfold window chamber, we established that the NO donor group induced significant vasodilation compared to the vehicle group.SignificanceNO supplementation in an acute hemodilution with PE has beneficial effects on cardiac performance. However, the NO supplementation effects with a NO donor are dose-independent and short-lasting. 相似文献
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Vieira LM Kijjoa A Silva AM Mondranondra IO Kengthong S Gales L Damas AM Herz W 《Phytochemistry》2004,65(4):393-398
The CHCl(3) extract of the bark of Garcinia speciosa contained four 17,14-friedolanostanes and five lanostanes as well as friedelin and common plant constituents. The friedolanostanes were the previously known methyl ester of (24E)-3 alpha,23 alpha-dihydroxy-17,14-friedolanostan-8,14,24-trien-26-oic acid and the methyl esters of three hitherto unknown acids, 3 alpha-hydroxy-16 alpha,23 alpha-epoxy-17,14-friedolanostan-8,14,24-trien-26-oic acid, 3 alpha,23 alpha-dihydroxy-8 alpha,9 alpha-epoxy-17,14-friedolanostan-15-oxo-24-en-26-oic acid and 3 alpha,23 alpha-dihydroxy-17,14-friedolanostan-15-oxo-8(14),24-dien-26-oic acid. New lanostanes were 3 beta,9 alpha-dihydroxylanost-24-en-26-al and the methyl ester of 3 beta-hydroxy-23-oxo-9,16-lanostadien-26-oic acid. Structures were established by analysis of spectroscopic data. In the case of the lanostanes the previously unassigned C-25 stereochemistry was shown to be 25R by X-ray analysis of 3 beta-hydroxy-23-oxo-9,16-lanostadien-26-oic acid. In the case of the friedolanostanes the configuration at C-23 was established as 23R, identical with the absolute configuration at C-23 of mariesiic acids A and B. 相似文献
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S C Chaiyaroj K Kotrnon S Koonpaew N Anantagool N J White S Sirisinha 《Microbiology and immunology》1999,43(7):625-630
We reported previously two biochemically and antigenically distinct biotypes of Burkholderia pseudomallei. These two distinct biotypes could be distinguished by their ability to assimilate L-arabinose. Some B. pseudomallei isolated from soil samples could utilize this substrate (Ara+), whereas the other soil isolates and all clinical isolates could not (Ara-). Only the Ara isolates were virulent in animals and reacted with monoclonal antibody directed at the surface envelope, most likely the exopolysaccharide component. In the present study, pulsed-field gel electrophoresis was employed for karyotyping of these previously identified B. pseudomallei strains. We demonstrate here that the DNA macrorestriction pattern allows the differentiation between B. pseudomallei, which can assimilate L-arabinose, and the proposed B. thailandensis, which cannot do so. Bacterial strains from 80 melioidosis patients and 33 soil samples were examined by genomic DNA digestion with NcoI. Two major reproducible restriction patterns were observed. All clinical (Ara-) isolates and 9 Ara- soil isolates exhibited macrorestriction pattern I (MPI), while 24 soil isolates (Ara+) from central and northeastern Thailand displayed macrorestriction pattern II (MPII). The study here demonstrated pulsed-field gel electrophoresis to be a useful tool in epidemiological investigation possibly distinguishing virulent B. pseudomallei from avirulent B. thailandensis or even identifying closely related species of Burkholderia. 相似文献
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