食品污水中异养硝化-好氧反硝化菌Bacillus sp.JG441的筛选鉴定及其脱氮特性

高氨氮、高盐、含有机物的食品工业污水处理难度大、周期长,添加高效硝化菌株可以大幅提高污水处理效率。本研究通过高盐培养基,从腌渍食品厂排放污水中筛选出一株对复杂环境有较强耐受性的新型高效异养硝化-好氧反硝化菌株JG441,经鉴定为Bacillus sp.,对其脱氮条件、异养硝化、好氧反硝化、极端环境耐受和脱氮通路进行研究。结果表明,菌株JG441可以利用(NH₄)₂SO₄和KNO₃为氮源进行异养硝化和好氧反硝化;在NaCl浓度为30g·L^-1,苯酚浓度为400mg·L^-1时,24h NH₄⁺-N去除率可达99%,在NH₄⁺-N浓度为500mg·L^-1时,24h NH₄⁺-N去除率为57.4%。菌株JG441脱氮能力强,在高盐含氮和成分复杂的污水处理方面具有较好应用潜力。     

高浓度纤维素的离子液体溶液中均相乙酰化反应(英文)

At relatively high cellulose mass concentrations (8%, 10%, and 12%), homogeneous acetylation of cellulose was carried out in an ionic liquid, 1-allyl-3-methylimidazolium chloride (AmimCl). Without using any catalyst, cellulose acetates (CAs) with the degree of substitution (DS) in a range from 0.4 to 3.0 were synthesized in one-step. The effects of reaction time, temperature and molar ratio of acetic anhydride/anhydroglucose unit (AGU) in cellulose on DS value of CAs were investigated. The synthesized CAs were characterized by means of FT-IR, NMR, and solubility, mechanical and thermal tests. After the acetylation, the used ionic liquid AmimCl was easily recycled and reused. This study shows the potential of the homogeneous acetylation of cellulose at relatively high concentrations in ionic liquids in future industrial applications.     

温度和游离氨对絮状和颗粒污泥硝化系统的短期影响(英文)

The short-term effects of temperature and free ammonia (FA) on ammonium oxidization were investigated in this study by operating several batch tests with two different partial nitrification aggregates, formed as either granules or flocs. The results showed that the rate of ammonium oxidation in both cultures increased significantly as temperature increased from 10 to 30 °C. The specific ammonium oxidation rate with the granules was 2-3 times higher than that with flocs at the same temperature. Nitrification at various FA concentrations and temperatures combination exhibited obvious inhibition in ammonium oxidation rate when FA was 90 mg·L 1 and tempera- ture dropped to 10 °C in the two systems. However, the increase in substrate oxidation rate of ammonia at 30 °C was observed. The results suggested that higher reaction temperature was helpful to reduce the toxicity of FA. Granules appeared to be more tolerant to FA attributed to the much fraction of ammonia oxidizing bacteria (AOB) and higher resistance to the transfer of ammonia into the bacterial aggregates, whereas in the floc system, the bacteria distributed throughout the entire aggregate. These results may contribute to the applicability of the nitrifying granules in wastewater treatment operated at high ammonium concentration.     

Fe(Ⅲ)Cit还原菌的分离及其性能的优化

从化学吸收-生物还原集成系统内的混合培养物中分离得到一株高效还原Fe(III)Cit(Cit:柠檬酸)的菌株,对其进行分子生物学鉴定,归属为肠球菌属,命名为Enterococcussp.FR-3。同时,考察了碳源种类和浓度、氮源种类和浓度、菌种接种量以及pH等因素对FR-3生长及Fe(III)Cit还原性能的影响,优化微生物生长及还原Fe(III)Cit的条件。结果表明,葡萄糖为FR-3生长和Fe(III)Cit还原的最佳碳源,其最适添加浓度为1000mg·L-1。NH4Cl作为氮源时菌种FR-3生长和Fe(III)Cit还原效果明显优于NaNO2,且NH4Cl只要维持100mg·L-1左右即可。菌种接种量在150mg·L-1时Fe(III)Cit还原率达到最大。过量碳源、氮源用量以及或接种量对还原过程没有促进作用。适合Fe(III)Cit还原的pH值范围为6.6~7.0。     

利用农业废弃物和诱导剂提高海洋内生拟盘多毛孢菌J63的漆酶产量(英文)

Pestalotiopsis sp. J63, producing a high activity of laccase, is a new marine-derived fungus isolated from the oceanic sediment of the East China Sea. Since the marine environment is oligotrophic nutrient, marine de-rived fungi may use small amount of nutrients to grow and produce laccases. Agricultural residues that are mainly composed of lignin, cellulose and hemicellulose are difficult to be degraded and few microbes can take them as sub-strates, so they are considered as oligotrophic nutrient and have the potential to be used to produce value added products. In this study, the ability of Pestalotiopsis sp. J63 to use agricultural residues to produce laccases was tested in the submerged fermentation. The combination of 3 g·L-1 maltose and 20 g·L-1 rice straw was the best car-bon sources and 8 g·L-1 ammonium sulfate was the best nitrogen source under the condition without inducers. The effects of five inducers, the feeding time and concentration of inducer on laccase production were investigated. Adding 0.09 mmol·L-1 phenol after 24 h of incubation led to high laccase activity （5089 U·L-1）, while with 0.09 mmol·L-1 phenol in the medium and wheat bran as the nitrogen source, the laccase activity could reach 5791.7 U·L-1. Native-PAGE results showed that two laccase isozymes were present in the cultures. One existed in both in-duced and non-induced culture filtrates, while the other was only found in the fermentation with the addition of phenol, guaiacol and veratryl alcohol.     

一株异养硝化菌的分离鉴定及其最佳亚硝化条件

采用传统微生物分离纯化方法,从焦化废水活性污泥中筛选到一株高效去除氨氮并显著积累亚硝酸盐氮的异养硝化细菌C16.该菌株为G-,短杆状;菌落为白色、半透明.经形态、生理生化特性以及16S rRNA基因序列分析,初步鉴定该菌属于产碱杆菌属(命名为Alcaligenes sp.C16).对该菌的异养硝化功能进行了研究,结果表...     

异养硝化菌的分离及脱氮特性研究

从活性污泥中分离得到异养硝化菌株Y1,该菌的最优硝化条件：C／N为9．6,温度为30％,初始pH为9．0,摇床转速为250r／min。在此条件下,初始浓度为152．88mg／L的氨氮经8h降解后浓度降低到4．02mg／L,硝化过程中未发现中间产物亚硝酸氮和硝酸氮积累。菌株Y．不仅具有异养硝化作用,还能以硝酸氮作为唯一氮源进行好氧反硝化作用,40h内对初始浓度为196mg／L的NO3--N降解率为99．05％。     

活性污泥中异养硝化-好氧反硝化菌的分离及其脱氮性能

该文从活性污泥中分离出三株高效的异养硝化-好氧反硝化菌。这些菌经形态特征和生理生化特征分析以及16S rRNA鉴定,命名为B.subtilis CL1、B.subtilis CL9和G.terrae CL6。在以柠檬酸钠为碳源、硫酸铵为氮源、初始氨氮浓度为50 mg/L、碳氮比为20、温度为30℃、pH为7、反应时间为48 h的条件下,B.subtilis CL1和B.subtilis CL9对氨氮的去除率均为99%,对总氮的去除率分别为98%和96%。以乙酸钠为碳源,其他条件与上述两种菌相同的条件下,G.terrae CL6对氨氮和总氮的去除率均达到100%,且在硝化过程中没有亚硝酸盐氮或硝酸盐氮的累积。     

一株异养硝化-好氧反硝化菌株L3的筛选鉴定及其脱氮特性

从广东三水罗非鱼养殖池底泥分离筛选出一株具有高效降氮能力的异养硝化-好氧反硝化细菌L3。通过形态学,生理生化以及16S rRNA基因序列分析鉴定该菌株为青岛假单胞菌Pseudomonas qingdaonensis。研究了该菌株对三种含氮模拟废水的脱氮特性及降氮过程的pH耐受范围,进一步采用响应面法探究了温度、pH、C/N、溶氧量及其交互作用对菌株L3脱氮性能的影响。结果表明,该菌株处理高浓度含氮模拟废水48 h后NH₄⁺-N、NO₃^--N、NO₂^--N的去除率分别达到90.50%、65.24%、85.34%,且在酸性条件下(pH=4)有较强的降氮能力;响应面法结果表明菌株最佳脱氮条件为温度29.1℃,C/N为11.7,摇床转速175 r/min,pH为6.2,其中温度、碳氮比及二者之间的交互作用对NH₄⁺-N去除率的影响显著;在最优条件下,菌株L3处理模拟氨氮废水12 h后对NH₄     

硝酸浓度对橄榄石基活性炭特性的影响(英文)

In this work we investigated the effect of nitric acid concentration on the pore structure, surface chemistry and liquid phase adsorption of olive stone based activated carbon prepared by mixing process using phosphoric acid and steam as activating agents. Chemicals and textural characterization show that the increase of HNO3 concentration increases considerably the total acidic groups but decreases specific surface area and pore volume. The study of adsorption in aqueous solutions of two organics, phenol and methylene blue, on raw and oxidized activated carbon indicates that the treatment of mixed activated carbon with different concentrations of nitric acid improves the adsorbent capacity for methylene blue at HNO3 concentrations less or equal to 2 mol·L 1, while it has a negative effect on phenol adsorption.     

石油烃降解菌的分离鉴定及其产生乳化剂条件

从天津塘沽原油污染海滩的泥样中分离得到一株石油烃降解菌SY095,经生理生化及16S rRNA基因序列分析鉴定为红球菌(Rhodococcus sp.)。该菌株能以正十六烷为碳源代谢产生一种对柴油等烃类具有良好乳化作用的生物乳化剂。菌株SY095产生乳化剂的最适宜条件为:正十六烷10g/L,初始pH值为7.2,30℃下160r/min摇床培养2d。在此条件下,培养液表面张力降到最低值,约32mN/m;经测定,其临界胶束浓度(CMC)值约为75mg/L。     

Isolation and Polyacrylamide Gel-Urea Electrophoretic Characterization of α S1 -Casein

Abstract

An improved method for the isolation of pure α _S1 -casein from pooled milk is described. The method involves chemical isolation followed by DEAE-cellulose column-chromatographic fractionation.

Alpha _S1 -casein was characterized by SGUE, PGUE, chemical, and sedimentation analyses. The chromatographically pure α _S1 -casein was found to contain α _S1 -B and α _S1 -C casein variants. These variants cannot be separated by DEAE-cellulose column chromatography.

The preparation contained 1.10%P, equivalent to 10 phosphorus atoms per mole of 28,500. The molecular weight by approach to sedimentation equilibrium was 25,500. Alpha _S1-casein in 0.1 M KCl, pH 5.6, showed random aggregation of 14S, while in tris-citrate buffer, pH 8.6, it showed 1.5 S, and in Na-PO₄ buffer, pH 7.0, 4.2 S species.     

耐酸异养菌的分离及在电镀污泥处理中的应用

生物淋滤是去除电镀污泥中重金属的有效手段,但所用硫杆菌易受污泥中多种有机物毒害,从而影响淋滤效果。本文介绍了一种将耐酸异养菌与硫杆菌混合培养进行生物淋滤的方法。从电镀污泥中分离得到一株耐酸异养菌,经基因鉴定为芽孢杆菌(Bacillus sp.),与硫杆菌复配后对电镀污泥进行生物淋滤,可将淋滤时间由7d缩短至3d,淋滤效果也有一定的提升。     

萘降解菌的筛选及降解性能的初步研究

微生物降解是多环芳烃从土壤和水环境中消失的主要途径。本文从加油站废油排放口附近被污染土壤中筛选到两种降解萘的混合菌H1、H2并从中分离出一株纯菌C_1。研究发现,利用纯无机盐培养基加萘作为唯一碳源要比加入其它营养物质的培养基对于筛选萘降解菌更为有利。H_1、H_2和C_1均能以萘为唯一碳源生长,在萘初始浓度为1000mg/L的纯无机盐培养基中培养40h后,培养液中微生物数量分别增长10倍以上,利用气相色谱测得萘的降解率都达到99．6％以上。     

一株产高温纤维素酶菌株的分离筛选

从牛粪堆肥中,筛选出一株产高温纤维素酶的菌株。通过形态学观察,初步判定为木霉属菌株,命名为木霉SW-04。该菌株经初始摇瓶发酵后测定粗酶液CMC酶活力2.179 IU/m L,最适反应温度为70℃,在50、60、70、80、90℃分别保温60 min后,仍可分别保持62.7%、61.8%、72.2%、68.1%、54.8%的酶活力,证明该酶具有较好的热稳定性。     

一株正十六烷降解菌的分离鉴定及其降解性能研究

从长沙某长期受油料污染土壤中驯化筛选得到一株正十六烷降解菌YJ1,经形态特征、生理生化特征、16S rDNA序列分析及系统发育树分析等对其进行鉴定,初步确定菌株YJ1属于短芽孢杆菌属(Brevibacillus)。并通过单因素实验研究了不同培养条件(初始pH值、培养温度、接种量和正十六烷初始浓度)对菌株YJ1生长的影响及其对正十六烷的降解性能。确定菌株YJ1的最适培养条件为:初始pH值7、培养温度30℃、接种量10%、正十六烷初始浓度10 mL·L~(-1)。在最适条件下培养15 d,菌株YJ1对正十六烷的降解率可达66.7%,降解效果良好。     

PLA降解菌的分离鉴定及其产酶和降解特性

以山东潍坊使用聚乳酸/聚己二酸-对苯二甲酸丁二酯共混物(PLA/PBAT)地膜的土壤为样本，采用以聚乳酸(PLA)为唯一碳源的无机盐培养基筛选PLA降解菌。使用形态学观察、生理生化实验、16S rRNA基因序列分析及构建系统发育树等方法鉴定降解菌。通过水解圈法确认产蛋白酶活性高的降解菌为研究对象，并采用福林酚法结合单因素及响应曲面法对外源营养源与产酶条件进行了优化。采用SEM、FTIR和XRD等方法分析了降解前后PLA的形貌和结构变化，研究了降解菌对PLA的降解情况。结果表明：从土壤中筛选获得了一株产蛋白酶的PLA降解菌(门多萨假单胞菌Pseudomonas mendocina)；优化得到的最佳产酶条件为：在100 mL筛选培养基中，加入质量分数为2%的葡萄糖和质量分数为1%的胰蛋白胨作外源营养源，pH为7.4，接种量为1.4 mL及培养温度32 ℃。在此条件下，蛋白酶活性最高为32.15 U/mL，较未优化前提高约26倍；PLA降解菌产蛋白酶可催化降解PLA材料中的酯键，5 d内PLA降解率可达29.35%。     

两株铁还原菌的分离鉴定及特性研究

利用富集培养的方法从兰州市七里河污水处理厂二沉池活性污泥中分离出两株铁还原菌,命名为B1和B3。通过两株菌的生长性能及铁还原特性测定发现该菌6 h便可进入对数生长期且具有较高的铁还原能力。采用Logistic方程拟合分离菌株还原参数,两株菌拟合方程相关性的决定系数R2为0.9757、0.9426,拟合效果良好。通过形态学特征和生理生化特征分析以及16sr DNA基因序列分析,B1和B3均与klebsiella亲缘关系最为接近,相似性达99%,初步鉴定为克雷伯氏杆菌。     

一株产脂肽类生物表面活性剂菌株的分离及代谢产物分析

采用多次富集培养、血平板筛选方法,从新疆克拉玛依油田油水样中分离得到产生物表面活性剂菌株L1。该菌株与已培养的土壤芽孢杆菌(Brevibacillus agri)的16S rDNA序列同源性达到99%;其代谢产物具有降低表面张力的作用,可以将发酵液表面张力从最初的69.56 mN.m-1降到29.36 mN.m-1;菌株代谢产物经薄层层析分析初步鉴定为脂肽类生物表面活性剂,红外光谱定性该生物表面活性剂属于环脂肽类表面活性剂。