应用微生物组合技术治理富营养化水体的研究

应用光合细菌、硝化细菌、玉垒菌等高效微生物及其组合,采用悬浮与挂膜两种批式工艺,对比分析其对富营养化水体有机物的去除及含氮化合物的转化效果;同时,采用接触氧化反应器进行连续流试验考察其对氨氮的转化效果,结果证明,采用微生物组合技术处理方法治理富营养水体是切实可行的。

有益微生物组合加菌糠对菠菜生长及土壤养分的影响

在连续两茬菠菜盆栽试验中,施用不同的微生物菌糠,通过测定菠菜的株高、根长、生物产量,收获后土壤碱解氮、有效磷、速效钾、有机质含量,研究了不同有益微生物组合加菌糠对菠菜生长和土壤养分的影响。结果表明:几种有益微生物组合加菌糠皆可以促进菠菜生长、增加产量和提高土壤养分,以微生物组合1+菌糠处理效果最好。

探讨不同微生物组合发酵杏鲍菇菌糠及发酵条件优化

随着我国对生态环境建设的重视程度不断提高,对工业和农业的废物废渣进行回收利用的要求也与日俱增,这就在很大程度上推进了相关栽培技术的改革创新。其中较为明显的进步在于食用菌代料栽培原料的节能化,在这一栽培过程中产生的菌糠经合理发酵之后,具有较之以往更为丰富的营养价值,同时也推动了资源的节约和发酵技术的改进。这也就意味着菌糠产生后的市场潜力是通过较为科学的发酵过程来实现的,否则便会使自身价值得不到有效开发,因此,要加强对菌糠发酵的重视,优化菌糠发酵的综合条件,从而推动菌糠的广泛应用。以发酵杏鲍菇菌糠为出发点,对不同微生物组合发酵结果进行论述,进而阐述优化发酵条件的思路。

光催化与微生物组合技术处理印染废水研究进展

概述了印染废水水质特点以及单一技术(光催化技术、生物技术)处理印染废水的局限性。同时介绍了分段式光催化与微生物组合技术和一体式光催化与微生物组合技术处理印染废水的研究进展以及组合技术在未来研究的方向。

几种除臭微生物的高效组合筛选

为加强微生物除臭产品的开发,在前期筛选出的枯草芽孢杆菌、细黄链霉菌、生香酵母、米曲霉等4种除臭微生物的基础上,采用L8(27)正交试验,优化设计其高效除臭组合。结果表明,"枯草芽孢杆菌+米曲霉"为最佳组合,0～15 d对NH3的去除率比其他组合差异显著或极显著;与空白对照相比,5 d、10 d、15d时,"枯草芽孢杆菌+米曲霉"对NH3的去除率分别为56.87%、28.26%、21.84%。

基于寡培养可视化的铀污染检测的微生物组合

为了评估监测铀污染对环境影响程度,为环境治理提供参考依据,本研究通过筛选获得对铀胁迫敏感和抗性的2类微生物,用以响应土壤或水体的铀污染,并考察其对铀污染响应灵敏度。实验筛选得到的红色敏感菌与粉色抗性菌经鉴定分别为粘质沙雷氏菌(Serratia marcescens)和玫瑰色考克氏菌(Kocuria rosea),明显的菌落特征实现了微生物检测的可视化与简单化。通过寡培养基的应用,成功地以粘质沙雷氏菌:玫瑰色考克氏菌为1∶2的比例构建了微生物检测体系。经验证,该体系在水体中能够检测出铀的最低浓度约为5 mg·L^(-1),在土壤中能检出的铀浓度高于10 mg·kg^(-1)才有明显效果,表明本微生物组合对于监测水体和土壤铀污染是有效的。该体系为水体和土壤铀污染的微生物监测提供了前期技术基础。同时,寡培养方式的使用为外界因素对微生物的影响的"效果保真培养"提供了一定的参考。

宝力格油田巴19断块微生物-凝胶组合驱技术研究

宝力格油田巴19断块属于中高温(58℃)油藏,原油物性差,以高蜡、高胶质为主体,油水黏度比高,注水指进导致水驱效率低,储层非均质性强,层内层间矛盾突出。根据油田的特点,以整体改善油田的水驱开发效果为目的,研究形成了以微生物驱为主体、凝胶调驱为辅的微生物凝胶组合驱技术,微生物改善原油物性,并适当开展调驱扩大微生物工作液的波及体积,提高微生物-凝胶组合驱效果。通过该项技术在宝力格油田持续应用,目前油藏菌体浓度保持在106个/ml左右,形成了整体的微生物场,原油黏度平均降低率48.1%,微生物凝胶组合驱可使采收率提高9.5%。自2010年开展微生物凝胶组合驱以来,巴19断块增加可采储量63.96×104t。

好氧/缺氧生物阴极型微生物燃料电池组合工艺处理含氮废水的研究

考察了好氧/缺氧生物阴极型微生物燃料电池(MFCs)组合工艺对模拟氨氮废水的处理情况,该组合工艺由好氧MFC(O-MFC)和缺氧反硝化MFC(A-MFC)组成。结果表明:连续运行时,O-MFC和A-MFC的输出功率分别为14.2 W/m3和8.8 W/m3,对COD、氨氮和TN的去除率分别为98.8%、97.4%和97.3%。随着氨氮浓度的增加,A-MFC的功率密度增大,O-MFC的功率密度下降。当氨氮浓度为100 mg·L-1时。

不同微生物对猪粪堆肥过程及其养分状况的影响

为使集约化猪场固态猪粪无害化和资源化,采用耐温性和猪粪水适应性选择法,从新鲜猪粪和堆肥中分离出地霉菌、解脂耶罗威亚酵母菌、凝结芽孢杆菌、嗜热脂肪芽孢杆菌和奴卡菌5株,并采用五因素两水平正交试验法,设计出15种不同组合发酵菌剂,研究其将猪粪发酵成有机肥的效果。统计分析显示,地霉菌和嗜热脂肪芽孢杆菌为最佳菌种。结果表明,利用发酵菌剂与猪粪混合堆肥发酵,堆肥的最高温度可由自然腐熟的67℃提高到72℃,速效养分较自然腐熟提高9.5%。因此,选择合适的发酵菌剂与猪粪混合堆肥,可较好地实现猪粪变有机肥的目标。

内生沙福芽孢杆菌与生防细菌组合防治桉树青枯病研究

为探究桉树内生沙福芽孢杆菌NP91及生防细菌组合对桉树青枯病的生物防治效果,采用抑菌圈法测定桉树内生沙福芽孢杆菌NP91对青枯病菌的拮抗作用,并用共培养法检测其在桉树体内的定殖转运情况,同时通过蘸根法测定其对桉树青枯病的防治效果,最后通过菌株间的拮抗作用形成3个微生物组合:L-B-4+WCS358r+NP91(组合LWN)、L-B-11+CN181+NP91+WCS358r(组合LCNW)、CN181+WCS417r+NP91+WCS358r(组合CWNW),探究微生物组合对桉树青枯病的防治效果。结果表明,内生沙福芽孢杆菌对青枯病菌具有较强的拮抗活性,且能够在桉苗根部和茎部定殖,接种第15天时,定殖量在根部为6.35 lg CFU/g,在茎部定殖量达到5.23 lg CFU/g。在生防试验中,沙福芽孢杆菌NP91对青枯病的防治效果在第5天和第7天时分别为80.0%和43.8%,但随着时间延长,防治效果逐渐降低。通过多株生防细菌组合后,防治效果最好的组合LCNW对青枯病的防治效果在第7天时达到了100.0%,表明内生沙福芽孢杆菌通过与其他细菌组合可以显著提高对桉树青枯病的防治效果。

发酵豆粕改善仔猪生长性能、营养物质消化率和肠道微生物菌群

为了提高豆粕的营养价值(SBM),选用3种微生物对豆粕进行发酵处理。采用3×3正交实验设计,通过对发酵豆粕(FSBM)中肽和抗营养因子含量进行测量分析,推测出豆粕发酵中枯草芽孢杆菌、汉逊酵母和干酪乳杆菌等微生物用量最佳比例2︰1︰2(P<0.05)。进一步动物实验表明,在哺乳期(7-28d),采用10%发酵豆粕替代豆粕对仔猪生长性能没有明显的影响(P>0.05)。然而,与没有添加发酵豆粕和添加6%血浆蛋白粉组相比,在断奶仔猪日粮中添加10%发酵豆粕和不同水平的血浆蛋白粉(0,2%,4%和6%)组断奶仔猪(d28-38)均可获得更高的日增重和饲料转化率(P<0.05)。此外,分别采用不同水平的发酵豆粕(3.75%和7.5%)和大豆浓缩蛋白(SBPC)(3.75%和7.5%)替代38-68日龄仔猪日粮中豆粕,与对照组相比,发酵豆粕和大豆浓缩蛋白组均可提高营养物质消化率、粪便中淀粉酶活性以及乳酸菌的数量,并降低粪便中大肠杆菌数量(P<0.05)。以上实验结果表明,发酵豆粕对仔猪营养物质消化率和肠道菌群有正调控作用。

不同菌剂组合处理猪场沼液试验效果评价

规模化猪场沼液的深度净化处理是养殖污水无害化处理与资源化利用的必由之路。选取4种厌氧菌剂(a、b、c、d)和2种好氧菌剂(e、f),比较研究不同菌剂组合对猪场沼液的净化效果,旨在研制适合处理猪场沼液的菌剂组合,为养殖废水资源化循环利用提供科学依据。结果表明:10个菌剂组合对猪场沼液均具有一定的净化效果,能够较好地去除沼液BOD5、氨氮、总磷、粪大肠菌群,最高去除率分别达到99.3%、98.7%、64.0%、99.9%。综合评估,菌剂组合3、4、5优于其他菌剂组合。

天然抗病毒药物的组合微生物转化

抗病毒药物的研发是现今药物开发的热点,也是难点。分析抗病毒药物研发的关键性困难和障碍,在生物合成药物学、天然药物的生物转化学、药物设计学、免疫学、病毒学等学科知识基础上,借鉴组合化学、组合生物催化、高通量筛选等当今较前沿的药物研发途径和技术,提出了"组合微生物转化"的研发理念和相应途径,以应用于天然抗病毒药物的研发和药理毒理改造。

Microstructure and biocorrosion behaviors of solution treated and as-extruded Mg-2.2Nd-x Sr-0.3Zr alloys

Mg-2.2Nd-xSr-0.3Zr alloys （x=0, 0.4 and 0.7, mass fraction, %） were prepared by gravity casting. Solution treatment was conducted on the as-cast alloys to homogenize microstructure, and hot extrusion was subsequently conducted. Microstructure was observed using an optical microscope and a scanning electron microscope. Biocorrosion behaviors of the alloy in simulated body fluid were analyzed by mass loss, hydrogen evolution and Tafel polarization experiments. The results show that the amount of residual eutectic phase of the solution treated alloys increases with increasing Sr addition, and the grains are significantly refined after hot extrusion. The corrosion resistance of the solution treated alloys deteriorates apparently with increasing Sr addition, while the corrosion resistance of the as-extruded alloys is improved with Sr addition. Nevertheless, the biocorrosion behavior of the as-extruded alloys obtained by Tafel polarization shows different trends from those obtained by the other two methods.

Directional solidification and characterization of NiAl-9Mo eutectic alloy

Ni-45.5Al-9Mo （mole fraction,%） alloy was directionally solidified with a constant temperature gradient （GL=334 K/cm） and growth rates ranging from 2 to 300 μm/s using a Bridgman type crystal growing facility with liquid metal cooling （LMC） technique. The effect of growth rate （v） on the solidified microstructures such as rod spacing （λ）, rod size （d） and rod volume fraction was experimentally investigated. Two types of the solidified interfaces, planar and cellular, were identified. On the condition of both planar and cellular eutectic microstructures, the relationships between λ, d and v were given as： λv1/2=5.90 μm·μm1/2·s1/2 and dv1/2=2.18μm·μm1/2·s1/2, respectively. It was observed that the volume fraction of Mo phase could be adjusted in a certain range. The variation of phase volume fraction was attributed to undercooling increase and the growth characteristics of the individual constituent phases during the eutectic growth.

Microstructure and properties of Ti64.51Fe26.40Zr5.86Sn2.93Y0.30 biomedical alloy fabricated by laser additive manufacturing

From the perspective of biomechanics and forming technology,Ti−Fe−Zr−Sn−Y eutectic alloy was designed using a“cluster-plus-glue-atom”model,and then the alloy was prepared by laser additive manufacturing(LAM)on pure titanium substrate.The mechanical properties of the alloy were evaluated using micro-hardness and compression tester,and the elastic modulus was measured by nanoindenter.The results show that the alloy exhibits a high hardness of HV(788±10),a high strength of 2229 MPa,a failure strain of 14%,and a low elastic modulus of 87.5 GPa.The alloy also has good tribological,chemical,forming,and biological properties.The comprehensive performances of the Ti64.51Fe26.40Zr5.86Sn2.93Y0.30 alloy are superior to those of the Ti70.5Fe29.5 eutectic alloy and commercial Ti−6Al−4V alloy.All the above-mentioned qualities make the alloy a promising candidate as LAM biomaterial.

Lower Bifidobacteria counts in both duodenal mucosa-associated and fecal microbiota in irritable bowel syndrome patients

AIM: To determine the composition of both fecal and duodenal mucosa-associated microbiota in irritable bowel syndrome (IBS) patients and healthy subjects using molecular-based techniques. METHODS: Fecal and duodenal mucosa brush samples were obtained from 41 IBS patients and 26 healthy subjects. Fecal samples were analyzed for the composition of the total microbiota using fluorescent in situ hybridization (FISH) and both fecal and duodenal brush samples were analyzed for the composition of bif idobacteria using real-time polymerase chain reaction. RESULTS: The FISH analysis of fecal samples revealed a 2-fold decrease in the level of bifidobacteria (4.2 ± 1.3 vs 8.3 ± 1.9, P < 0.01) in IBS patients compared to healthy subjects, whereas no major differences in other bacterial groups were observed. At the species level, Bifidobacterium catenulatum levels were significantly lower (6 ± 0.6 vs 19 ± 2.5, P < 0.001) in the IBS patients in both fecal and duodenal brush samples than in healthy subjects.CONCLUSION: Decreased bifidobacteria levels in both fecal and duodenal brush samples of IBS patients compared to healthy subjects indicate a role for microbiotic composition in IBS pathophysiology.

Production of Poly（3-hydroxybutyrate-co-3-hydroxyhexanoate） by Recombinant Pseudomonas stutzeri 1317 from Unrelated Carbon Sources

Synthetic biology promises to simplify the construction of metabolic pathways by assembling the de- tached modules of the whole pathway. This gives new approaches for the microbial production of industrial products such as polyhydroxyalkanoates （PHA）. In this study, to produce poly（3-hydroxybutyrate-co-3-hydroxyhexanoate） （PHBHHx） by Pseudomonas stutzeri 1317 from unrelated carbon sources such as glucose, the phaCl-phaZ-phaC2 operon of P. stutzeri 1317 was knocked out to generate the PHA deficient mutant P. stutzeri 1317LF. Then three modules containing phaCahAReBRe, phaCahBReGep and phaCAhPah were introduced into P. stutzeri 1317LF separately The shake flask results indicated that the precursor supply and PHA synthase activity were the vital factors for the PHBHHx accumulation of P. stutzeri 1317LF. Furthermore, the PHBHHx accumulation of the recombinants from different carbon resources were performed. The highest PHBHHx content was 23.7% （by mass） with 58.6% （by mole） 3HB fraction. These results provide basis for further improving the PHBHHx accumulation of P. stutzeri from unrelated carbon sources.

Monitoring Soil Microbial Activities in Different Cropping Systems Using Combined Methods

Cropping activities may affect soil microbial activities and biomass,which would affect C and N cycling in soil and thus the crop yields and quality.In the present study,a combination of microcalorimetric,enzyme activity(sucrase,urease,catalase,and fluorescein diacetate hydrolysis),and real-time polymerase chain reaction(RT-PCR) analyses was used to investigate microbial status of farmland soils,collected from 5 different sites in Huazhong Agriculture University,China.Our results showed that among the 5sites,both positive and negative impacts of cropping activities on soil microbial activity were observed.Enzyme activity analysis showed that cropping activities reduced soil sucrase and urease activities,which would influence the C and N cycles in soil.Much more attentions should be given to microbial status affected by cropping activities in future.According to the correlation analysis,fluorescein diacetate hydrolysis showed a significantly(P < 0.05) negative correlation with the time to reach the maximum power output(R ——0.898),but a significantly(P < 0.05) positive correlation with bacterial gene copy number(R = 0.817).Soil catalase activity also showed a significantly(P < 0.05) positive correlation with bacterial gene copy number(R = 0.965).Using combined methods would provide virtual information of soil microbial status.