Effect of salinity on microbial densities of soil in the dilution plate technique applied in mangrove areas

作者简介:张瑜斌(1970～) ,男,湖南郴州人,博士,副教授,主要从事海洋微生物学与海洋生态学研究. E2mail: zhangyb@gdou. edu. cn 通讯作者Corresponding author. E2mail: linpeng@jingxian. xmu. edu. cn[中文文摘]在使用稀释平板法分离潮间带红树林及其对照光滩土壤微生物以及计数时,多数情况下使用陈海水制作培养基和稀释水,很少考虑培养基和稀释水的盐度对最终计数结果的影响。使用稀释平板法研究了盐度对福建九龙江口红树林区与深圳福田红树林保护区土壤微生物平板计数的影响,结果表明培养基与稀释水盐度对微生物数量有明显的影响。统计分析显示细菌的海水稀释效果优于淡水,而放线菌与真菌则刚好相反(P<0.05,一个例外)。海水不适合配制红树林区土壤微生物平板计数的培养基,从0~35,高盐度的平板培养基会降低微生物的数量,尤其是放线菌的数量,尽管培养基的盐度对真菌影响无规律,但细菌数量在低盐度时比在高盐度和不加氯化钠时要多。根据盐度效应,提出了稀释平板技术应用于潮间带的红树林及其相应光滩时的优化方法,认为细菌应该用海水作无菌稀释水,而放线菌和真菌则应用淡水作稀释水;包括光滩在内的红树林区土壤微生物分离与计数的培养基宜控制较低盐度范围。[英文文摘]When the soilmicrobial densities are determined in mangroves and correspondingmudflat at the same tidal level by the dilution p late method, the agarmedia and dilution water are generallymade up of aged seawater in most cases, and effects of salinity in agar media and dilution water on the enumeration of microbes is seldom taken into consideration. The effects of salinity on soil microbial counting from the samples in mangrove areas in Jiulongjiang Estuary of Fujian, and Futian Mangrove Nature Reserve of Shenzhen, China, were tested by dilution p late technique. The results showed that the soil microbial densities in mangroves and mudflat were significantly influenced by the salinity of dilution water and agarmedia. For the bacteria, the seawater served as sterilized dilution water was significantly ( P < 0. 05) more benefic to the enumeration on the p lates than the freshwater, but in reverse for the actinomycetes and fungi. The increasing salinity of media within 35 significantly decreased microbial colonies on the p lates, especially for the actinomycetes, in sp ite of the fact that the effect of salinity ofmedia on fungal numberswas not indefinite. The bacterial colonieswere more abundant on the agar p lates with low salinity than with high salinity or without any NaCl. It was p roposed that some methodological imp rovements were needed when the dilution p late technique was app lied to microbial counting in the samp les of mangrove forest and mudflat at the same tidal level in inter2tidal zone. The sterilized dilution water should be p repared with seawater for the bacteria, but with freshwater or low saline water for the actinomycetes and fungi. The salinity of agarmedia should be low for the microbial isolation and enumeration of soil samples from the mangrove areas including mudflats.国家自然科学基金资助项目(30270272

Mechanism and kinetics of cellobiose hydrogenation catalyzed by Ru/CNT

联系人及第一作者: 谭雪松( 1985- ),男, 硕士, 助理研究员。[中文文摘]引言化石资源的日益枯竭,使得人们对从可再生生物质资源合成化学品和燃料的研究给予了广泛关注[1-2]。木质纤维素是地球上分布最广、产量最多的生物质资源之一。纤维素由葡萄糖通过β-1,4糖苷键连接而成,其分子的刚性结构和高度结晶性使其成为最难转化的多糖[3]。目前通过高温气化或热解转化纤维素为合成气等燃料的工艺过程已经建立[4]。但在温和条件下通过平台分子继而生成油品或化学品的过程还有待开发。山梨醇是纤维素转化中有价值的平台分子之一,可以在较温和条件下通过水汽重整和费托合成等方法合成烷烃燃油和化学品[5-6]。因而,对纤维素催化加氢制备山梨醇的研究将有助于纤维素的有效利用。Fukuoka等[7]报道了在水相体系下,铂/氧化铝催化剂催化纤维素加氢制备山梨醇的反应,在190℃反应24h,山梨醇的收率为25%。Liu等[8]利用高温水形成的独特酸性质,以钌/活性炭为催化剂,245℃反应得到山梨醇,收率为30%。Deng等[9]利用碳纳米管优异的氢吸脱附与溢流性质,以Ru/CNT为催化剂,在185℃反应24h,山梨醇收率达到36%。虽然在催化纤维素加氢制山梨醇的研究方面已取得一定成果,但山梨醇收率不高(<40%),高效催化体系 依旧缺乏, 开展相关基础研究仍十分必要。纤维二 糖是纤维素的次级结构单元, 由两个葡萄糖通过 β-1,4糖苷键连接而成。由于纤维二糖结构与纤维 素类似, 且易于溶解, 故可用于研究纤维素转化的 模型分子[ 10-11] 。 本研究考察了以Ru/ CNT 为催化剂, 水相条 件下催化纤维二糖加氢制备山梨醇的反应。推导了 纤维二糖转化反应机理, 建立了纤维二糖催化加氢 反应的动力学模型, 可为纤维素的催化加氢研究提 供指导。[英文文摘]The production of chemicals or fuels from renewable biomass resources especially cellulose has attracted much attention because of the worldwide demand for less dependence on fossil resources.However,the direct utilization of cellulose is still a challenge because of its robust crystalline structure.Herein,the hydrogenation of cellobiose,a typical cellulose,over carbon nanotube supported ruthenium catalyst (Ru/CNT) was reported.The mechanism of cellobiose conversion was proposed and the kinetic equation was obtained. Based on the kinetic experiments carried out in the range 120- 185℃ under 5. 0 MPa H2 , the reaction rate constants and activation energies of each reaction step in cellobiose hydrogenation were obtained with MATLAB, in which the activation energy for hydroly sis and hydrogenolysis of cellobio se was est imated as 147.1 kJ·mol- 1 and 71.2 kJ·mol- 1, respectively. The obtained kinetic model and some general rules on the catalyt ic hydrog enation of cellobio se may provide impo rtant data for eff icient ut ilization of cellulose.国家自然科学基金项目(20625310, 20773099,20873110

Expression of RGS16 protein induced by wide type p53 gene in rat glioma C6 cell line

目的:探讨内外源性野生型p53是否可以诱导大鼠胶质瘤细胞C6RGS16表达。方法:在大鼠胶质瘤细胞C6中,分别转染pEGFP-C3-wtp53或以400ng/ml表阿霉素诱导内源性野生型p53表达,于处理后0h、4h、8h、16h、26h、32h和52h收集细胞爬片、固定后免疫细胞化学检测p53蛋白与RGS16蛋白表达。结果:转染pEGFP-C3-wtp53后4h、8h、16h、26h和32h时均检测到p53蛋白表达,在8h和16h时检测到RGS16蛋白表达;在400ng/ml表阿霉素处理后,仅在26h时检测到p53表达而始终未见到RGS16蛋白表达。结论:内外源性野生型p53可以诱导大鼠胶质瘤细胞C6RGS16蛋白的表达

Effect of Exogenous RGS16 Gene Transfection on Growth of Glioma Cell Line C6

背景与目的:有研究表明野生型p53可以诱导RGS16表达,而RGS16可能与胶质瘤的发生有关。本研究旨在探讨RGS16基因转染对大鼠胶质瘤C6细胞生长的影响。方法:构建真核表达载体pIRES2-EGFP-RGS16,脂质体法转染C6细胞,经G418筛选后荧光显微镜观察细胞中增强型绿色荧光蛋白(enhancedgreenfluorscentprotein,EGFP)的表达,RT-PCR证实RGS16的mRNA表达,免疫细胞化学方法检测细胞中RGS16蛋白表达。最后利用流式细胞仪、生长曲线、平板克隆形成等方法研究RGS16基因对胶质瘤细胞周期、生长及增殖的影响。结果:成功构建了稳定表达RGS16和表达空载体的细胞系C6-RGS16、C6-GFP。C6-RGS16、C6-GFP和C6经流式细胞仪检测S期的细胞比例分别为28.5%、18.9%和14.3%(P<0.05);生长曲线表明C6-RGS16生长的速度明显快于C6-GFP及C6,但其平板克隆形成率分别为12%、25%和25%(P<0.05)。结论:RGS16促进C6细胞周期从G1期向S期过渡,加快细胞生长速度,但是并不促进细胞克隆形成。 【英文摘要】 BACKGROUND & OBJECTIVE: Wild type p53 could induceRGS16 mRNA expression, and RGS16 protein is related with carcinogenesisof glioma. This study was designed to investigate the effects of exogenousRGS16 gene transfection on the growth of rat glioma cell line C6.METHODS : A eukaryotic expression plasmid pIRES2-EGFP-RGS16 wasconstructed, and transfected into C6 cells. The cells were selected by G418.The expression of enhanced green fluorescent protein (EGFP) was observedunder fluorescent microscope, and the exp...军队医药卫生科研基金项目(No.02ma04)~

Regulation of Cell Cycle of Glioma C6 Cells by Regulator of G Protein Signaling 16

目的:探讨G蛋白调节子 16(RGS16)对胶质瘤C6细胞周期的影响。方法:利用脂质体介导法将RGS16基因导入C6细胞中 ,在倒置显微镜下观察细胞形态变化和贴壁生长情况 ;免疫细胞化学法检测转染前后RGS16蛋白的表达情况 ;流式细胞仪检测转染pCMV 5 RGS16和 pCMV 5质粒后每隔 12h后的细胞周期变化。 结果:转染pCMV 5 RGS16质粒 2 4h后 3 0 .0 %细胞贴壁性降低 ,突起收缩 ,细胞变圆 ,72h之后细胞又恢复正常 ;RGS16蛋白的表达呈时相性 ,3 6h时表达率最高 (阳性率为13 .0 % ) ,72h表达终止 ;C6细胞的各期细胞比例变化与RGS16蛋白表达对应 ,在 3 6h时G1期比例从转染前的 70 .5 %降低到60 .2 % ,S期比例从 2 0 .9%增加到 3 4.9% ;在 48h时G1期增加到 76.2 % ,S期减少到 11.4% ;72h各期恢复到正常比例。对照组细胞转染前后形态变化不明显 ,RGS16蛋白表达阴性 ,细胞周期变化不明显。结论:RGS16能促进C6细胞周期的运行. 【英文摘要】 Objective To study the effect of regulator of G protein signaling 16(RGS16) on the cell cycle of glioma C6 cell.Methods pCMV5 RGS16 was transfected into C6 cells by lipofectin.The morphological and adhesive changes of the cells were observed under an inverted microscope.Expression of RGS16 was examined by immunocytochemical method both before and after the transfection.Flow Cytometry was adopted to measure the fraction number changes of the cell cycle phase every 12 h.Results 24 hours after the transfec..

Recent Advances in Fluorophosphate and Orthosilicate Cathode Materials for Lithium Ion Batteries

Corresponding authors.SHI Zhi-Cong, Email: [email protected]; Tel: +86-411-39893938. YANG Yong, Email: [email protected]; Tel: +86-592-2185753.[中文文摘]综述了用于锂离子电池的氟磷酸盐和正硅酸盐正极材料的研究现状,重点对各种材料的结构及合成方法与性能的关系,特别是对如何改善材料的电化学性能进行了总结和探讨.展望了这两类锂离子电池正极材料的发展趋势.[英文文摘]We review recent research on fluorophosphate and orthosilicate cathode materials for lithium ion batteries.Emphasis is placed on the relationship between structures,methods of preparation and properties of the cathode materials.We especially focus on factors leading to an improvement in their electrochemical performance.Trends of research into fluorophosphate and orthosilicate cathode materials are also discussed.高等学校博士学科点专项科研基金(20090041120020); 中央高校基本科研业务费专项资金(DUT10JN06)资助项

Tissue Culture Technique of Acacia mangium Elite Trees

作者简介: 黄烈健( 1971—) ，男,博士,副研究员,研究方向为林木遗传育种与森林培育，电话: 020-87033463,E-mail: hlj@ ritf.ac.cnTaking Acacia mangium elite trees as explants，the tissue culture technique system for dormant bud of 3-5 year-old elite trees was established． The system includes the germination-inducing of the dormant buds，the multiplying of shoots，the rooting of adventitious shoots，and the pre-treating and transplanting of seedlings． The medium MS + Sucrose 30 g·L－1 + BA 0.5 mg·L－1 + NAA 0.1 mg·L－1 was used for inducing the dormant buds; the medium MS + BA 1.0 mg·L－1 + NAA 0.05 mg·L－1 was used for multiplying; while the medium 1 /2 MS +IBA 2.0 mg·L－1 + NAA 0.5 mg·L－1 was used for rooting.The results revealed that it was viable to producing field seedlings with micropropagation.Although the branches with dormant buds harbored many kinds of microbes and the adventitious shoots were not easy to root，20% to 30% healthy germination could be yielded and the rooting rate of adventitious shoots could be higher than 85%.Pretreated with ABT powder ( rooting hormone) ，both the rooting rate and survival rate of adventitious shoots were nearly 100%．国家“十一五”科技支撑计划项目(2006BAD01A15-5,2006BAD32B010-3); 农业科技成果转化项目(2009GB24320482

Construction of the eukaryotic expression vector pIRES2-EGFP-Axin and its expression in glioma cells

目的:构建真核表达载体pIRES2EGFPAxin,并在神经胶质瘤细胞系C6中进行表达。方法:用PCR的方法扩增Axin基因,构建真核表达载体pIRES2EGFPAxin,经NheI及SalI双酶切鉴定并测序。通过脂质体法转染C6细胞,用荧光显微镜检测细胞中增强型绿色荧光蛋白(EGFP)的表达,用免疫组化染色的方法检测细胞中Axin的表达。结果:构建了真核表达载体pIRES2EGFPAxin,用脂质体法转染神经胶质瘤细胞C6后,经荧光显微镜和免疫组化染色法检测,可见细胞内有EGFP及Axin的表达。结论:成功地构建真核表达载体pIRES2EGFPAxin,并在神经胶质瘤细胞C6中表达,为研究Axin对肿瘤的生物学作用以及Axin在肿瘤基因治疗中的应用奠定了基础。国家杰出青年自然科学基金项目(No.30125012);; 军队医药卫生科研基金项目(No.02ma04);; 高等学校骨干教师及归国留学人员科研启动基金(No.1999747

Construction of the eukaryotic expression vector pIRES2-EGFP-Axin and its expression in glioma cells

目的:构建真核表达载体pIRES2EGFPAxin,并在神经胶质瘤细胞系C6中进行表达。方法:用PCR的方法扩增Axin基因,构建真核表达载体pIRES2EGFPAxin,经NheI及SalI双酶切鉴定并测序。通过脂质体法转染C6细胞,用荧光显微镜检测细胞中增强型绿色荧光蛋白(EGFP)的表达,用免疫组化染色的方法检测细胞中Axin的表达。结果:构建了真核表达载体pIRES2EGFPAxin,用脂质体法转染神经胶质瘤细胞C6后,经荧光显微镜和免疫组化染色法检测,可见细胞内有EGFP及Axin的表达。结论:成功地构建真核表达载体pIRES2EGFPAxin,并在神经胶质瘤细胞C6中表达,为研究Axin对肿瘤的生物学作用以及Axin在肿瘤基因治疗中的应用奠定了基础。 【英文摘要】 AIM: To construct the eukaryotic expression vector pIRES2-EGFP-Axin, and to express Axin in C6 glioma cells. METHODS: The Axin gene was amplified by PCR using pCMV5-HA-Axin as a template, and confirmed by DNA sequencing. The eukaryotic expression vector pIRES2-EGFP-Axin was constructed by introducing Axin DNA fragment into the sites of Nhe I and Sal I of pIRES2-EGFP vector. The plasmid was transfected into the C6 cells using lipofectamine. The expressed EGFP was observed under fluorescent microscope and the...国家杰出青年自然科学基金项目(No.30125012);; 军队医药卫生科研基金项目(No.02ma04);; 高等学校骨干教师及归国留学人员科研启动基金(No.1999747

p38MAPK与HSP70关系的初步研究

高等学校骨干教师资助计划 ;; 留学归国人员科研启动基金([1999] 747号