Studies on polysaccharides from marine organism, a review

国家自然科学基金资助项目(49676302

Study on Extraction and Purification of SOD from Garlic Cells

[中文文摘]对从大蒜细胞中提取超氧化物歧化酶(Superoxidedismutase,SOD)的工艺过程进行了研究。通过对热变性法、等电点法、丙酮分级沉淀法和硫酸铵盐析法等几种方法的实验分析比较,找出一套操作简便SOD总收率高的分离纯化工艺。[英文文摘]An extraction process to purify superoxide dismutase (SOD) from garlic cells was studied in this paper.By comparing the experimental results obtained by some different ways of treatment,such as heat treatment,isoelectric fractionation,acetone fractionation and (NH4)2SO4 salting out,a new and simple process was found to achieve the high SOD recovery with specific activity

Screening of marine bacterial strain with immunoactive exopolysaccharide

从厦门海区潮间带的动植物体及底泥分离到的177株海洋细菌中筛选出一株高产胞外多糖的1202菌株.其产生的胞外多糖可显著地促进昆明种小鼠脾淋巴细胞IL 2(白介素 2)的合成,并对小鼠S180肉瘤具有较强的抑制作用.经初步分类鉴定,确定该菌株归属于土壤杆菌属(Agrobacteriumsp.).An exopolysaccharide-producing strain 1202 was obtained by screening 117 marinebacteria isolates, which were from the flora ,the fauna and the sediments in the intertidal zone of the Xiamen coast. The exopolysaccharides produced by the bacterial strain 1202 could stimulate interleukin 2 (IL-2) secretion from mouse spleen lymphocytes in vitro, and exhibit significant inhibitory effects on sarcoma 180 solid tumors in vivo. The strain 1202 was tentatively identifiedas a species of the genus Agrobacterium, based on its morphology, growth features, physiological and biochemical characteristics.国家自然科学基金资助项目(30070024

Suitable Culture Conditions for Exopolysaccharides Produced by Marine Bacterial Strain 1202

应用响应面法(ResponseSurfaceMethod,RSM)对海洋细菌1202菌株胞外多糖发酵培养基进行优化.结果表明,适宜的发酵培养基组成为:蔗糖4%,酵母膏0.05%,玉米浆1.5%,CaCO30.15%,KH2PO40.08%,MgSO4·7H2O0.05%,FeSO4·7H2O0.01%,NaCl0.1%,pH7.5.在装液量为50mL(500mL三角瓶),接种量5%时,于28℃摇瓶培养7d,胞外多糖的产量可达到8.3mg/mL,转化率为20.75%.The response surface method (RSM) was used to optimize the medium for production of exopolysaccharides by marine bacterium 1202. The optimal fermentation conditions were established with 5% inoculum size and 500 mL Erlenmeyer flask containing 50 mL medium, which consisted of 4% sucrose,1.5% corn steep liquor,0.05% yeast extract,0.15% CaCO3,0.05% MgSO4·7H2O,0.08% KH2PO4,0.01% FeSO4·7H2O,0.1% NaCl,pH7.5.The fermentation was carried out at 28℃ for 7 days on a rotary shaker.Under these conditions, the yield of exopolysaccharide reached 8.3 g/L,and the conversion rate of sucrose was 20.75%.国家"863"计划(2001AA620401);; 国家自然2100.651.30.25科学基金(30070024)资

Studies on growth situations of Hg-superaccumulating recombinant E.coli in heavy metal wastewater

［中文文摘］对具超强汞富集能力的基因工程菌在重金属汞离子存在的水体中的生长状况进行了研究。实验所采用的基因工程菌由于外源基因的表达而对Hg2 + 产生了一定的耐受力 ,而且这种耐受力经IPTG诱导后还能得到进一步的增强 ,耐受能力从Hg2 + 浓度 5mg/L提高到 15mg/L。IPTG加入的时机对菌体的生长和耐受力的有效诱导是重要的。一般在OD6 0 0 为 0 .5～ 0 .8时加入 ,且加入后还应保证 2h左右的诱导时间。实验结果还表明菌体在生长过程中对碳源的要求很低。［英文文摘］The growth situations of recombinant E.coli JM109 which can superaccumulate Hg 2+ from aqueous solution containing Hg 2+ were studied. The Hg 2+ resistance ability of the recombinant bacteria was observed due to the expression of exogenous genes, and the ability could be further improved from 5mg/L of Hg 2+ concentration to 15mg/L by means of IPTG induction. The suitable time to add IPTG was important for bacteria growth. Basically IPTG was supposed to be added as OD600 reached 0. 5～0. 8. Furthermore , at least 2 hours of induction period of time was needed to ensure the ef2 fective induction of Hg2 + resistance. The experiment results also showed that the recombinant bacteria could grow at a very low concentration level of carbon source.教育部优秀青年教师资助计划资

Screening of marine actinomycetes producing polysaccharides with immunomodulating activity

用硫酸苯酚法和实验动物模型检测分离于厦门海区潮间带的 996株海洋放线菌胞外多糖产量和体内外免疫增强活性 .结果表明 ,3 3%的海洋放线菌粗多糖产量大于 3g/dm3;在粗多糖产量高的海洋放线菌中有 3株菌株的胞外多糖在体内外均具有较好的免疫增强活性 ,其中链霉菌 (Streptomycessp .) 2 30 5菌株的胞外多糖具有较高的非特异性、细胞及体液免疫增强活性 .研究结果表明海洋放线菌胞外多糖是免疫调节剂开发的重要资源 .The purpose of this work is to investigate the production of the extracellular polysaccharides(EPS) with immunomodulating activity from marine actinomycetes. 996 strains of marine actinomycetes are isolated from intertidal zone of Xiamen Island, and 3.3% of them yield EPS more than 3 g/dm 3 when determined by method of phenol-sulfuric acid. Among the strains with high yield of EPS, there are 3 strains those produe the EPS having immunomodulating activity in vitro by promoting the proliferation and accumulation of interleukin 2 (IL-2) of lymphocytes of mouse spleen and in vivo in the animal model. The EPS produced by Strain 2305, Streptomyces sp., is the most promising candidate to develop into immunomodulator in view of its obvious effects on the non-specific, cellular and humoral immunity. The results show that the EPS from marine actinomycetes can be an important resource for the development of immunomodulators.国家海洋“863”计划资助项目 ( 819- 0 5 - 0 8) ;; 福建省科委重点资助项目 ( 98-Z - 7

Uptake of Nickel from Industrial Wastewater by Genetically Engineered Escherichia coli JM109

[中文文摘]利用通过基因工程技术所构建的在细胞内同时表达出高特异性镍转运蛋白和金属硫蛋白的基因工程菌富集水体中的镍离子。菌体细胞对Ni2 + 的富集速率很快 ,富集过程满足Langmuir等温线模型。与原始宿主菌相比 ,经基因改造的基因工程菌不仅最大镍富集容量增加了 5倍多 ,而且对pH值、离子强度的变化及其它共存重金属离子的影响都呈现出更强的适应性。相比而言 ,Na+ 、Ca2 + 、Cd2 + 、Pb2 + 的影响较小 ,但Mg2 + 、Hg2 + 和Cu2 + 所引起的负面效应较大。进一步的实验表明基因工程菌对Ni2 + 的富集行为不需要外加营养物质。[英文文摘]　Heavy metal wastewater poses a serious threat to the environment . In comparison to the existing methods of chemical precipitation , ion exchange and carbon adsorption , biosorption is an attractive alternative for the recovery of heavy metals from industrial effluents. However , nickel ion , different fromother heavy metal ions , is a more recalcitrant pollutant and has low affinity to many metal tolerant microorganisms. In this study , Escherichia coli JM109 was genetically engineered to simultaneously express a Ni2 + transport system (the product of nixA gene) andoverexpress metallothionein (MT) . NixA protein has a high affinity for Ni2 + , and metallothioneins (MTs) are capable of binding a variety of heavy metals including Ni2 + . The Ni2 + bioaccumulation performance of the genetically engineered E. coli JM109 was evaluated. Time2course test showed that the bioaccumulation rate was rapid , and 95% of the accumulation was achieved within the first 10 minutes. The maximum Ni2 + bioaccumulation by genetically engineered E. coli cells was dramatically increased from 1154mgPg to 10111mgPg , a more than fivefold increase than that of the original E. coli strain. The isothermwas of Langmuir type. Within the tested pH range (pH 4～10) , the engineered cells displayed more resistance to pH variation , retaining up to 80 %of the Ni2 + binding capacity at pH4 , while the original E. coli host cells lost 80 % of Ni2 + binding capacity at pH 4. The presence of Na + and Ca2 + affected Ni2 + bioaccumulation, but the effects were not serious , as 71% and 66% of the Ni2 + binding capacities were retained respectively at the concentrations of 1000mgPL Na + and 1000mgPL Ca2 + . However, Mg2 + exerted a severe adverse effect on Ni2 + bioaccumulation ,83% of Ni2 + accumulating capacity was lost when Mg2 + concentration reached 200mgPL. The effects of different kinds of heavy metals on Ni2 + accumulating were different . The genetically engineered E. coli cell lost less than 45% of its Ni2 + bioaccumulation activity in the presence of 50mgPL lead or cadmium, 66% in the presence of 25mgPL mercury and 84% in the presence of 40mgPL copper. The presence of glucose did not improve Ni2 + uptake. Our study suggests that the genetically engineered E.coli JM109 has potential application for effective and efficient recovery of nickel from aqueous solutions.教育部留学回国人员启动基金资

Treatment of Wastewater Containing Sulfuric Acid and Sulfate by Solvent Extraction Process

［中文文摘］采用溶剂萃取法处理含硫酸及硫酸盐的工业废水 ,主产优质农用硫酸钾 ,副产氯化铵和氮钾复合肥 ,整个工艺过程基本无三废排放 ,实现了对该废水的综合有效治理。［英文文摘］Industrial wastewater containing sulfuric acid and sulfate can be treated by solvent extraction process to produce potassium sulfate with high quality as main product, and ammonium chloride and nitrogenour phosphatic fertilizer as byproducts. The process can realize comprehensive and efficient treatment of the wastewater basically without discharging wastes

Studies on the Chemical Composition of Sea Cucumber Mensamaria Intercedens Ⅲ. Immunomodulative Effects of PMI-1

研究了二色桌片参多糖－１（ＰＭＩ－１）在体内、体外的免疫调节作用．结果表明，二色桌片参多糖－１体外能促进小鼠脾淋巴细胞增殖，促进小鼠脾淋巴细胞分泌ＩＬ－２；体内能显著促进迟发型超敏反应，增加脾指数、胸腺指数；具有显著的免疫增强作用。The immunoactivities of PMI-1 are studied in vivo and in vitro. PMI-1(5. 50. 100u g/mL ) in vitro could promote the proliferation of mice lymphocyte, and increase IL-2 production as well. In vivo, PMI-1 could significantly improve the delayed-type hypersensitivity (DTH) degree and the weights of spleen and thymus, although it has little effect on the production of hemolysin antibodies. The results indicate that PMI-1 could remarkedly enhance the immunofunction in mice