Advanced Materials Research Vols. 535-537

Abstract: To observe the effects of hydroxycamptothecine(HCPT) on the growth and apoptosis of gastric cancer cell line. The viability of human leukemia cell line K562 was determined by MTT, cell morphology was observed under AO staining and electron microscopy, the apoptosis was measured using flow cytometry analysis. The results indicated that the growth of human leukemia cell line K562 was significantly inhibited by HCPT, and the IC50 was 8.0µg/mL. Morphological variations of apoptosis were observed at 48 hours treated with HCPT by AO staining and apoptosis body was observed under electron microscope. The results indicated that HCPT can suppress the growth of human leukemia cell line K562 and induce apoptosis of the cells.

Abstract: We report efficient syntheses of the clinical agent cladribine (2-chloro-2′-deoxyadenosine, CldAdo), which is the drug of choice against hairy-cell leukemia and other neoplasms, from 2-chloroadenosine. Treatment of 3´, 5´-O-triacetyl-2-chloroadenosine (4) with PTC-Cl and followed by HCO2Na and (Bu4N)2S2O8 gave high yields of the 2´-deoxy-3´,5´-O-triacetyl-2-chloroadenosine which can be converted into target product after convenient deprotection step. This method avoids of using toxic Sn regent which is good for the medical industry production.

Abstract: By using a new kind of single-beam normalized photo-acoustic tomography spectroscopy (PAS-CT) technology with non-damage detection, the photo-acoustic tomography spectroscopy, optical absorption properties and photosynthetic pigment content of the green and yellow leaves of Michelia alba were studied. The results show that: photo-acoustic tomography spectroscopy could be obtained from different chopping frequency and different sample position. The more photosynthetic pigment content the leaves of Michelia alba contains, the bigger optical absorption coefficient and the higher photosynthetic efficiency they have. In the research, we could find that the photosynthetic pigment content of the green leaves of Michelia alba is higher than that of the yellow ones. As a result, the optical absorption coefficient and the photosynthetic efficiency of the green ones are higher than the yellow ones. The photo-acoustic tomography spectroscopy technology could be a kind of non-damage detection to confirm the growth of trees.

Abstract: To observe the effect of ADM on cells apoptosis of SGC-7901 cells. The SGC-7901 cells were treated by ADM. And the inhibitory ratio of cells was measured by trypan blue stain assay, the IC50 value was calculated. Cells apoptosis were detected by DNA agarose gel electrophoresis.The cell cycles were analyzed by flow cytometry system after treatment with ADM. Morphologic changes were observed using phase-contrast microscopy . The SGC-7901 cells proliferation were remarkably inhibited by ADM. The IC50 values were 5.7 μg / mL. The typical DNA ladder on agarose gel electrophoresis for analysis of cellular apoptosis were significantly appeared. ADM could restrain the SGC-7901 cells proliferation, and to cause the morphologic changes of apoptosis. Apoptosis peaks appeared with flow cytometry analysis.

Abstract: Cornstalk, among the agricultural residues and other non-wood fiber, is a more promising source of lignocellulosic materials for bioethanol production. Pretreatment is an essential step in the enzymatic hydrolysis of biomass and subsequent production of bioethanol. Kinetic models can have practical applications for the optimization of the process and performance analysis, or economic estimations, so investigate the cornstalk hydrolysis kinetics is necessary. In this paper, effects of temperature and time on cornstalk hydrolysis in saturated formic acid with 4% hydrochloric acid solution reaction kinetics have been investigated. The results showed that the hydrolysis velocities of cornstalk were 0.021 h−1 at 60 °C, 0.0302 h−1 at 65 °C and 0.060 h−1 at 70 °C, the degradation velocities of glucose were 0.061 h−1 at 60 °C, 0.0845 h−1 at 65 °C, and 0.24 h−1 at 70 °C, the activation energy of cornstalk hydrolysis was 99.60 kJ/mol, and the activation energy of glucose degradation was130.94 kJ/mol.

Abstract: Bamboo is thought as an alternative feedstock for the production of fine chemicals, such as fuel ethanol and lactic acid to reduce our reliance on fossil fuels. Pretreatment is an essential step in the enzymatic hydrolysis of biomass for bioethanol production. In this study, hydrolysis of bamboo fiber for fermentable sugars production in hydrochloric acid used as a catalyst in saturated formic acid solution were studied. The purpose of this study is to investigate the effects of the hydrochloric acid concentration, temperature, the ratio of solid to liquid and reaction time on the fermentable sugars production. The optimum conditions were: adding 4% hydrochloric acid in saturated formic acid solution, temperature of 65 °C, 4% of the ratio of solid to solvent, with a reaction time of 90 min, under these conditions, the hydrolysate contained 23.52% glucose and 28.51% reducing sugars.

Abstract: The biosorption of uranium by Deinococcus radiodurans cells under culture conditions was studied in this research. The growth curve showed that uranium did not markedly inhibit the growth of Deinococcus radiodurans cells in short culture time. The biosorption results showed that the Deinococcus radiodurans cells had high biosorption capability for uranium under culture conditions with max biosorption efficiency of 86%, and max biosorption quantity of 230 mg g^-1. The results indicated that Deinococcus radiodurans can be used as the good radioactive wastewater decontamination biosorbent under culture conditions

Abstract: We present a facile electrochemical deposition process to grow zinc oxide (ZnO) nanosheet structures on indium tin oxide (ITO) substrate. The deposited ZnO was applied to immobilization of glucose oxidase and construction of glucose electrochemical biosensor due to a large surface area and good biocompatibility. The direct electron transfer of GOD immobilized on ZnO nanosheets was achieved and could be used to determination of glucose. Such ZnO nanosheet structures provide a good matrix for protein immobilization and biosensor fabrication.

Abstract: The aim of this study is to investigate the utilization of scoria as PRB reactive media for the removal of petroleum hydrocarbon from groundwater. Tests of comparison of scoria with powdered activated carbon(PAC) show that scoria has a larger capacity for petroleum hydrocarbon sorption than PAC. The particle size has weak effect on purification petroleum contaminated groundwater. The results of isothermal adsorption test show the high sorption capacity of the scoria(1.7g/g for TPH).The acquired sorption data are well fitted to the Langmuir isotherm.Careful examination of scoria’s composition and microstructure suggests that the sorption behavior is not only physical sorption but also chemical sorption,but mainly controlled by physical sorption .We recommend scoria as an economic,efficient and environmental friendly sorbent for petroleum hydrocarbon in contaminated groundwater.

Abstract: The pretreatment of corn stover with dilute sulfuric acid has been investigated by varying the acid concentration (0.5%-1.25%(w/w)) and the temperature (130-160°C). The pretreatment is aimed at improving enzymatic hydrolysis and increasing the fermentability of the biomass. Given the overall sugar yield, the most favourable pretreatment condition was performed with 0.75% sulfuric acid at 150°C for 30min and then with an enzyme loading of cellulase 15 FPU per gram of cellulose, and it resulted in a total of 49.74g glucose and xylose from 100g dry corn stover. The fiber physical feature, structure and property of pretreated residues were studied with Scanning Electron Microscope (SEM) and Fourier transform infrared spectroscopy. The SEM pictures indicated that the biomass structure was deformed and its fibers were exposed by the pretreatment. FTIR study showed that lignin and hemicellulose were partially removed during the diluted sulfuric acid pretreatment.