湄洲湾海洋细菌降解石油烃研究

研究了从湄洲湾海域分离的两个菌株HI和H2对石油的降解作用。实验测定了在5个不同源油初始浓度下的原油降解率,并考察了在原油初始浓度3000mg/l,6d的培养过程中,培养液的OD值及原油降解率的变化。分别以正十一烷,正十六烷,正二十四烷,萘和菲5种纯烃配制成3种混合烃养基,以考察两个菌株对芳烃及烷烃的降解能力。结果表明,两个菌株对烷烃和芳烃都有较高的降解速度和耐油性,但对底物的利用和对含N,P营养盐的要求有显著的不同,H1菌株不需要营养盐,对芳香烃降解特别有效;而H2菌株需要营养盐,对烷烃的降解较为有效。     

盐碱土壤多环芳烃降解菌群筛选及其降解特性

为了强化多环芳烃（PAHs）污染盐碱土壤原位微生物修复的应用,并提供高效的菌种资源,从天津大港油田盐碱化的油污土壤中富集分离出1组高效降解菲、芘的耐盐碱菌群,分离获得可培养优势细菌5株、真菌3株,考察了该菌群对菲、芘的降解效果,并进行了其对菲、芘降解特性分析。结果表明,该菌群在菲、芘质量浓度分别为25、50和75 mg/L 的液体无机盐培养基中培养15 d,菲、芘的降解率分别达到75.3%和53.6%、 56.6%和52.0%、 25.2%和13.6%;该菌群对菲、芘降解具有较广泛的盐质量分数和 pH 值范围,在菲、芘初始质量浓度各为50 mg/L,最适盐质量分数0~2%,最适 pH 值8.6条件下, 添加质量分数0.4%葡萄糖培养15 d 后,菲、芘的降解率显著提高,达到92.1%和65.8%。细菌16S rDNA 和真菌18S rDNA 测序结果表明,该菌群由叶杆菌属（Phyllobacterium）、假单胞菌属（Pseudomonas）、盐单胞属（Halomonas）、泛菌属（Pantoea）和青霉属（Penicillium）、双曲孢属（Sigmoidea）、胶孢炭疽属（Colletotrichum）组成。     

生物与胞外聚合物偶联降解石油污染土壤中常见有机物

将石油污染土壤中筛选出来的专一性降解萘菌株Rhodococcus、专一性降解菲菌株Nocardioides与胞外聚合物（EPS）联用,对石油污染土壤中常见的两种难降解有机物萘、菲的降解规律和动力学与菌株的生长曲线进行研究。实验结果表明, EPS与萘降解菌联用吸附降解萘的最佳萘初始投加量为2.14 mg/L,最佳pH值为6,最佳温度为30℃;EPS与菲降解菌联用吸附降解菲的最佳菲初始投加量为0.06 mg/L,最佳pH值为6,最佳降解温度为20℃。EPS与菌株联用对萘的去除率达96%时,菲的去除率达100%。     

微生物降解烷烃中间产物分离鉴定及代谢途径

为进一步提高微生物降解原油烃的效率,采用铜绿假单胞菌、蜡状芽胞杆菌和地衣芽孢杆3株采油菌株进行微生物降解烷烃途径研究,建立了中间产物分离制备方法,采用重氮甲烷衍生的方法对酸性中间产物进行甲基化衍生,实验菌株对正十四烷、正二十二烷和非正构烷烃化合物具有较高的降解能力.利用GC-MS方法,在实验菌株作用正二十二烷的产物中,检测到二十二烷酸、十八烷酸和十六烷酸,可以判断采油微生物是以末端单加氧的形式代谢正二十二烷生成二十二烷醇,然后进一步氧化成酸,进入β-氧化过程.该研究为微生物摄取原油中不同组分和控制降解过程、进一步改善微生物采油技术效果奠定了理论基础.     

固定化菌株NERC0401对甲基叔丁基醚降解的影响

采用间歇法考察了不同因素对海藻酸钙包埋固定菌株NERC0401(Klebsiella oxytoca)降解甲基叔丁基醚(MTBE)的影响,并分析了其降解反应动力学过程。实验结果表明,固定化菌株NERC0401对水体中MTBE的降解效果较游离态菌株NERC0401有所提高,对初始环境pH和MTBE初始质量浓度的适应性得到一定的改善。固定化菌株NERC0401对MTBE的降解反应过程近似符合一级动力学特征,MTBE初始质量浓度为39.0551mg/L时的降解动力学方程为lnρ=-0.066t+3.6887(ρ表示MTBE的质量浓度,mg/L;t表示反应时间,d),半衰期为3.41d。     

响应面法优化固定化微生物降解石油污染物

从炼油厂活性污泥中筛选和驯化了1株石油降解菌SJ-1,以秸秆材料WT为固定化载体,采用表面吸附法制备固定化微生物;以胜利原油为反应底物,考察了温度、微生物接种量、原油质量浓度、pH值对原油降解率的影响;采用响应面法优化了降解条件,并在优化条件下进行了降解动力学实验。结果表明,单因素对降解率的影响程度从大到小的顺序为温度、pH值、原油质量浓度、接种量,其中pH值和原油质量浓度、原油质量浓度和温度的交互影响对原油降解率影响较显著;根据响应面模型计算得到的最佳降解条件为pH值7.0、原油质量浓度5000 mg/L、温度34℃、接种量46 g/L,此时原油降解率最高达68.3%;固定化微生物和游离微生物降解过程均符合一级动力学,且前者的降解速率是后者的3.67倍。     

柴油组成对十六烷值与十六烷指数关联性的影响

考察了不同性质柴油以及烷烃、芳烃、烯烃含量对柴油十六烷值和十六烷指数关联性的影响。结果表明,中间基原油切割得到的柴油馏分十六烷值与十六烷指数吻合性好,对环烷基原油切割得到的柴油馏分十六烷值小于十六烷指数,石蜡基原油切割得到的柴油馏分十六烷值大于十六烷指数。直馏柴油十六烷值与十六烷指数关联最佳,加氢精制柴油次之,加氢裂化柴油最差。烷烃质量分数为30%～37%时,十六烷值与十六烷指数相近;芳烃质量分数为20%～30%时,十六烷值与十六烷指数相近,芳烃含量偏高时,十六烷值与十六烷指数关联性变差。当柴油密度为0.815～0.845g/mL时,十六烷指数采用GB/T11139—89计算较准确;当柴油密度大于0.845g/mL或小于0.815g/mL时,十六烷指数采用ASTMD4737—96四变量计算公式计算较佳。     

黄原胶降解菌的生长规律及影响因素

黄原胶降解菌是从土壤和水中分离出来的,它是以黄原胶为碳源进行生物降解的一类微生物.对黄原胶降解菌具有较强降解能力的为杆状菌和球菌,杆状菌菌体大小为(0.2～1.0μm)×(0.8～3.2 μm),球菌大小为0.2～0.4μm,革兰氏染色阴性.通过对黄原胶降解菌的生长规律及其影响因素研究,绘制出了黄原胶降解菌的生长曲线,确定出了其最适生长条件矿化度为5×103mg/L,pH值为7.5,温度为35℃,摇床转速为120 r/min,接种量为5%较适宜,黄原胶降解菌在黄原胶浓度为1～5 g/L范围内生长较快.     

生物转盘降解有机物的系统模拟

对生物转盘处理油田污水技术进行了数学模拟,并建立了动力学方程式。结果表明,反应速率常数受温度(Q)、水力停留时间(M)、pH值(N)等因素的影响。在N为7,Q为20℃,M为7 h,转速为4 r/min,盘片浸没面积为45%,进水化学需氧量(COD)为600 mg/L的条件下,生物转盘降解有机物的动力学方程为Cl=C0/exp(0.95×102Q-6.93M-0.70N-1.30t),式中:C0,Ct分别为进水和t时刻出水COD。     

海绵动物共附生微生物对海洋柴油污染物的降解作用及影响

目的 探索海绵动物共附生微生物对海洋柴油污染的生物修复作用。方法 以柴油降解率为指标从海绵中筛选降烃菌株,对降烃效果较好的3种菌株进行鉴定和复配,选出最佳降烃组合开展单因素试验和响应面优化试验,并构建柴油污染模型验证生物修复效果。结果 筛选降烃菌共38株,其中降烃效果最好的D1、D7、D8菌株分别鉴定为Halomonas aquamarina、Sphingopyxis terrae、Marinobacter aquaeolei;其降解率均在65%以上;3种菌株复配后优选最佳组合为D1-D7-D8;对降烃效果影响较大的3因素为初始pH值、柴油质量浓度和温度;对其响应面优化后得出最佳降解条件分别为7.41、32.79 g/L、30.65℃;按最优条件构建的模型实际降解率为84.17%,与预测值86.27%的吻合度较好。结论 该研究可为海绵-降烃菌系共生体的构建提供理论支撑,为解决海水中柴油污染难以集中处理的问题开辟新途径。     

一株喹啉降解菌的降解特性及代谢途径研究

从某石化厂污水处理站厂区内受石油污染的土壤中分离出1株能以喹啉为唯一碳源、氮源和能源生长代谢的菌株Q2。降解试验结果表明,Q2能将喹啉质量浓度为500 mg/L的培养液中的喹啉在32 h内完全去除,其降解喹啉的适宜温度为30 ℃、培养基初始pH值为8~10、摇床转速为100~200 r/min;喹啉浓度对Q2的降解有较大影响,喹啉质量浓度为195~796 mg/L时,Q2降解喹啉的过程符合零级动力学方程。生物降解过程中,培养液从黄色变为粉红色,最后呈棕色。红外光谱分析显示,Q2降解途径很可能为8-羟基香豆素途径,且杂环上氮原子以氨氮的形式释放。     

脱硫真核微生物烟曲霉的分离及脱硫性能研究

从被原油污染的土壤中驯化、筛选、分离得到具有自主知识产权的脱硫真核微生物烟曲霉ZJ-1（Aspergillus fumigatus Fresen. ZJ-1）。该烟曲霉ZJ-1在pH值为7、NaCl浓度为5 g/L、温度为30℃的条件下，生长状况较好，可耐受3～11范围的pH值变化和NaCl 25g/L形成的渗透压，具有较强的环境适应能力。该烟曲霉可以直接脱除油品中的有机硫，有一定的实际应用价值。     

喹啉降解菌的筛选及强化处理炼油废水的研究

从某石化厂区内受污染土壤中分离出1株能利用喹啉作为唯一碳源、氮源和能源的肠杆菌属（Enterobacter sp.）菌株,该菌对喹啉表现出优异的降解特性,在纯培养条件下,30 h内可将486 mg/L的喹啉降解完全。该菌不仅可高效降解炼油废水中高浓度的喹啉,同时还能与其它微生物协同作用,降解炼油废水中的其它有机污染物,从而进一步降低出水中的CODCr浓度。高浓度喹啉对硝化菌只存在短暂的抑制作用,1周左右硝化活性即可恢复,喹啉的生物降解过程中释放出氨氮,增加氨氮负荷,但氨氮去除率只出现短暂的下降。在喹啉质量浓度为200~686 mg/L的范围内,喹啉降解遵循零级反应动力学。     

Biodegradation of Petroleum Hydrocarbon by Pseudomonas Aeruginosa

A bacterial strain of the genus Pseudomonas aeruginosa was inoculated into a hydrocarbon culture medium and incubated for a definite period of time. The ability of the bacterial strain to biodegrade a hydrocarbon, viz. n-hexadecane, was evaluated through determining the hexadecane concentration in the inoculated culture medium on a gas chromatograph (GC). The effect of pH value on the degrading ability of the bacterial isolate and the impact of temperature on microbial growth were also explored. Test results showed that Pseudomonas aeruginosa was markedly effective in biodegrading n-hexadecane. Furthermore, the ability of Pseudomonas aeruginosa to biodegrade n-hexadecane was different at various pH values. Pseudomonas aeruginosa provided excellent degrading ability at a pH value of 7.0. The microbial cells of Pseudomonas aeruginosa increased with an increasing incubation duration at temperatures ranging from 28 ℃ to 35 ℃, and an exponential phase of microbial growth was observed.     

柴油脱硫菌的特性研究

针对传统加氢脱硫方法难以脱除柴油中含有的大量以噻吩、二苯并噻吩（DBT）等形式存在的含硫化合物,以DBT为模型化合物,筛选出以DBT为唯一硫源且降解DBT较好的菌株HT1,正交实验确定菌株发酵最佳条件为：温度30 ℃,硫源DBT质量浓度102.0 mg/L,氮源NH4NO3质量浓度2.0 g/L,碳源甘油质量浓度5 g/L,培养时间4 d,pH值7.0。硫源对菌株HT1的生长及脱硫效果的研究结果表明：硫源对菌株HT1的生长影响不大,但菌株HT1对以DBT为硫源的脱硫效果最佳。菌株HT1对其它含硫化合物的脱硫效果与含硫化合物的结构有关。菌株HT1对催化裂化柴油的脱硫率较低,有待进一步提高。     

Pseudomonas sp.LKY-5产生的表面活性剂提取及其稳定性研究

针对二苯并噻吩高效降解菌Pseudomonas sp.LKY-5降解过程中产生表面活性剂的现象,进行碳源优化,将提取分离出的表面活性剂进行化学组分分析和理化性质测定,考察温度、pH、无机离子对其表面活性稳定性的影响。结果表明,花生油为Pseudomonas sp.LKY-5产生表面活性剂的最佳碳源,产生的表面活性剂为鼠李糖脂,产量为0.15g/L,临界胶束浓度(CMC)为180mg/L,亲水亲油平衡值(HLB)为12.3,对柴油24h的乳化能力达61%。该表面活性剂在温度30~80℃、pH 6~13的条件下表面活性稳定,能够耐受200g/L的NaCl或MgCl2以及20g/L的CaCl2,稳定性能良好。     

The Isolation,Characterization, and Diesel Oil Denitrification of a Quinoline-Degrading Bacteria

Abstract

Quinoline is a poisonous organic compound and not easily biodegraded. From soil, wastewater, and activated sludge 19 bacterial strains were isolated by enrichment culture, which are able to use quinoline as the sole nitrogen source. Of the 19 strains, the HY9 strain is the best quinoline-degradation bacterium. Curves of the growth of HY9 and degradation of quinoline show that the growth of the HY9 strain and degradation of quinoline are concurrent, the optimum time is 50–70 hr, which is the stationary phase. Effects of carbon resource and the quantity of initial quinoline on degradation of quinoline are studied. The optimal carbon resource and quantity of initial quinoline amount are glucose 0.14 mL/100 mL. The orthogonal test determined optimal temperature, pH, time, and agitation speed, which are respectively 35°C, 7.0, 4 days, 125 rev/min. Temperature is the key factor, followed by pH and agitation speed, and time of culture is the least important factor. The denitrification rate of diesel oil is very low, only 13%. This is probably because the oil and water could not mix well; the key to strengthening the compatibility of oil and water is to try to improve the denitrification rate of diesel oil.     

Isolation and characterization of Bacillus amyloliquefaciens ZDS-1: Exploring the degradation of Zearalenone by Bacillus spp.

Zearalenone (ZEN) is a mycotoxin produced mainly by various Fusarium species which occur naturally in many crops worldwide. ZEN causes reproductive disorders and hyperestrogenic syndromes in animals and humans. This study aimed to isolate ZEN-degrading bacteria to develop strategies for detoxifying ZEN contamination in cereal crops. We screened approximately 1000 colonies for degrading ability and found four strains were capable of degrading ZEN. We selected one strain ZDS-1 for further study because it showed the high ZEN-degrading ability. On the basis of morphological, physiological and phylogenetic analysis of its 16SrRNA, gyrA gene sequences, strain ZDS-1 was identified as Bacillus amyloliquefaciens. The optimal conditions for the biodegradation of ZEN by ZDS-1 were temperature; 30 °C, pH; 6.0–7.0, and cell concentration; 5 × 10⁸ cfu/mL. ZDS-1 could degrade ZEN efficiently with the concentration from 1 mg/L to 100 mg/L. ZDS-1 not only could remove ZEN in the culture medium, but also could degrade ZEN in wheat. The ZEN removal by ZDS-1 was not due to binding or absorption, and during the process of ZEN degradation, no ZEN derivatives of ZEN were produced. These results suggested that Bacillus amyloliquefaciens ZDS-1 would be explored further for its ability to degrade ZEN in field trials.     

A New Technique for Measurement of Oil Biodegradation

Abstract

An active strain of anaerobic thermophilic bacteria was isolated from the environment of the United Arab Emirates. The strain, identified as Bacillus species, consists of two types—round and rod-shaped bacteria. This project studied the possibility of using these two types of bacteria for biodegradation of oil under elevated temperature conditions using a new method of measurement. Chemical and physical techniques were used previously to estimate the degradation rate of oil by microbes. In this project, a technique is was used to provide more accurate and reliable measurements. Visual inspection and measurements of oil drop size as a function of time were conducted. A computer image analyzer was used in this study to track bacterial growth and capacity to survive under different environmental conditions.

The temperature of the studied systems varied between 25°C and 70°C, and salt (sodium chloride (NaCl)) concentration varied between 0 and 50,000 ppm NaCl. The temperatures were selected to include typical sea water and reservoir temperatures in the Persian Gulf region. The average bacterial concentration used in this study was 182 × 10³ cells/mL. Experimental results indicated that the bacteria have the capacity to survive in saline and high temperature environments. The maximum oil degradation was observed at 70°C for all tested salinities. The degradation rate can be maximized by lowering the salinity and increasing the temperature of the studied systems. At a high temperature of 70°C, bacterial growth tends to improve at a low salt concentration, with a maximum oil degradation rate obtained at 10,000 ppm NaCl.     

双物料预聚法合成减阻剂及性能评价

采用可控予聚的方式合成了HG-2成品油减阻剂,聚合物的黏均相对分子质量大于3.0?106。 对柴油中加入50 mg/L HG-2减阻剂进行指标评价及台架试验和行车试验。结果表明：加入50 mg/L的减阻剂,对柴油性质影响不大,能符合GB252-2011普通柴油的要求;作为燃料,对车辆整体性能无明显的影响。在洛郑驻成品油管道进行了现场试验,加剂10 mg/L,柴油增输率可增加30.1%,加剂量8 mg/L,雷诺数为52 411,70 940,78 087时,对应的增输率分别为26.8%,30.2%,38.6%,增输效果较好。