945 resultados para Anaerobic Digestion


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本文从不同厌氧生境中获得7组(C-2、Y-2、L-2 、NZ、H-3、CZ、L-3)具有纤维素降解能力的复合菌系。经过不断传代、淘汰纤维素降解能力降低的菌系,最后得到一组高效、传代稳定的厌氧纤维素分解复合菌系L-3。该菌系可使滤纸在42 h内溃烂,并能在分解纤维素的同时产氢气。对L-3复合菌系的产酶条件进行了研究,结果表明,在实验范围内该菌系的产酶最适条件为:pH 6.5,温度37 ℃,接种量5 %,最佳碳源为滤纸,最佳氮源为硫酸铵。第10天测得羧甲基纤维素酶(CMCase)、滤纸酶(FPA)、外切葡聚糖酶(C1)、β-葡聚糖苷酶(β-glucodase)的酶活分别为0.216 U/ml、0.101 U/ml、0.132 U/ml、0.002 U/ml,滤纸失重率70.6 %。发酵代谢产物乙醇和丁酸含量分别可达1378 mg/L 、2695 mg/L,发酵产生的气体中氢气含量最高可达70.2 %。DGGE结果表明该菌系主要由14种菌组成,其中有三株菌在发酵前后菌数发生了明显的变化,说明在以滤纸为底物的降解过程中,这三株菌起到了重要作用,对这三株菌进行了分子生物学鉴定,初步定为Clostridium phytofermentans、Clostridium cellulovorans、Desulfovibrio sp。 利用实验室分离得到的纤维素降解菌,最终配制出由10、X-1、X-13、ST-13、L-3组成的好氧-厌氧纤维素降解复合菌剂。以秸秆为发酵底物,菌剂接种量1%,利用复合菌剂预处理后的秸秆,发酵总产气量相对于对照提高了71.62%,甲烷含量最高可达70.08%。 A group of microbial consortia L-3 was isolated from the anaerobic fermentation residue of corn stalk, which could degrade cellulose and produce hydrogen. The CMCase, FPA, C1 and β-glucosidase activity of L-3 could reach to 0.216 U/ml, 0.101 U/ml, 0.132 U/ml and 0.002 U/ml, respectively. In the filter degrading process, the filter paper collapsed in the liquid culture within 42 h and the filter degrading rate could reach to 70.6% in the 13 days, meanwhile, hydrogen was determined and the highest hydrogen content was 70.2%. The optimum cellulase-degrading conditions were filter papaer as the carbon source, (NH4)2SO4 as the nitrogen source, 37 ℃ and pH 6.5 in this experiment. DGGE results showed that the microbial consortia L-3 mainly included 14 strains. The amount of 3 strains were changed during the fermentation. These strains were identified as Clostridium phytofermentans、Clostridium cellulovorans、Desulfovibrio sp by 16S rDNA sequence analysis. The cellulose- degrading microbial agent was composed by 10, X-1, X-13, ST-13, L-3 which were isolated in the laboratory. The straw pretreated by cellulose-degrading microbial agent was used to ferment, the total biogas production increased by 72% comparing to the control. The content of methane could reach to 70.08%。

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本文对无介体双室微生物燃料电池的产电性能进行了初步研究,并根据不同运行阶段产电性能的优劣,对其中微生物的差异性进行了比较分析。全文分为两个部分: 第一部分:以乙酸钠为阳极原料构建双室微生物燃料电池(MFC),研究不同阴极受体、外接电阻、乙酸钠浓度和pH等因素对电池产电性能的影响,研究结果表明:在500mL的阴阳极反应体系中,选用乙酸钠作为阳极底物,质量浓度为6.46 g/L, pH 7.0,接入500Ω外电阻,阴极电子受体选择高锰酸钾的情况下,微生物燃料电池产电性能最好,最大电功率密度达到294.72 mW/m2,库伦效率能达到25.87%。在确定最适外接电阻阻值的同时对MFC内阻进行测定,阻值为871.87Ω。 第二部分:微生物燃料电池运行中,比较以厌氧污泥作为接种源的第一阶段和只接入附着有大量微生物电极的第二阶段的产电性能,得出第二阶段产电性能优于第一阶段,最大电功率密度达到353.57mW/m2,比第一阶段提高58.85 mW/m2;库伦效率为39.35%,增幅达52%左右;针对微生物燃料电池运行过程中,底物CH3COONa可能存在其它的代谢途径,本实验进行了第二阶段产电性能与CH3COONa消耗率关系以及阳极液面上方气体成分和含量的研究,发现第二阶段50h前CH3COONa的大量消耗主要用于微生物的生长,在整个运行过程中,阳极液面上方含有CH4和CO2;对气体测定的同时还发现,振荡能增强电功率密度的输出;通过对电极上和污泥中微生物差异性分析得出,δ-变形菌纲、β-变形菌纲和拟杆菌门的菌种更适应微生物燃料电池的运行环境,能在电极上大量富集,提高电池的产电性能,只接入附着有大量微生物的电极能有效降低热袍菌纲的菌种数量,降低了CH3COONa的无为消耗,有效提高了电池的库伦效率。 Electricity production in the mediator-less two-chambered microbial fuel cell(MFC) was researched. Based on the result in the different operation phase in the MFC, the microbial diversity was analysed. The paper involved two parts: Part 1: A two-chambered microbial fuel cell (MFC) was constructed with high-concentration sodium acetate as fuel in the anode. The influence of different electron acceptors in the cathode, external resistance value, pH value and concentration of sodium acetate on electricity generation in MFC was investigated. The result showed that the maximum power density of 294.72 mW/m2 and the coulombic efficiency of 25.87% was achieved at sodium acetate concentration of 6.46 g/L, pH 7.0, external resistance 500Ωin the anode and when using potassium permanganate as electron acceptor in the cathode. While decided the value of resistor, we found that shaking has effect on electricity production in the MFC. Part 2: Comparing the electricity production in different operation phases when using anaerobic sludge as inoculum in the first phase and microbes in the anodic electrode as inoculum in the second phase, the result showed that electricity production in the second phase was more than that in the first phase, the maximum power density of 353.57 mW/m2 and the coulombic efficiency of 39.35% was achieved, 58.85 mW/m2 and 52% more than that in the first phase, respectively. According to the fact that CH3COONa might be metabolized in other pathway in the running process in the MFC, we determining the relationship between electricity production and CH3COONa consumption, and the gas content in the anode, we found that CH3COONa was mainly used for microbe growth before 50h, and the anode contained CH4 and CO2. At the same time, we found that shaking could improve power density. The analysis on diversity of microbe in the anodic electrode and anaerobic sludge showed that δ-proteobacterium, β-proteobacterium and Bacteroidetes adapted themselves to the running environment of MFC. The anode could enrich them to improve the electricity production while reduced the quantity of Thermotogales, which were obligately anaerobic organotrophs with a fermentative metabolism, to increase the coulombic efficiency effectively.

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本文从四川绵竹酒厂、成都市龙泉长安垃圾填埋场以及四川大学荷花池底的厌氧污泥中先后分离得到63株厌氧产氢菌,其中H-8、H-61、HC-10等16株产氢细菌产氢能力较高,HC-10的产氢能力最高,最大产氢量和最大产氢速率分别达到2840 ml H2/L培养基和25.39 mmol H2/g drycell·h,对HC-10进行生理生化鉴定和分子生物学鉴定,判定其为clostridium sp.,对HC-10的产氢条件进行了研究,结果表明,该菌的最适生长温度为35 ℃,最适生长初始pH为7,以葡萄糖为最佳碳源,以蛋白胨为最佳氮源,不利用无机氮源,其产氢发酵液相产物以乙醇和乙酸为主,其发酵类型属于乙醇型发酵。此外,以酒糟废液作为底物,进行了菌株HC-10的生物强化试验,研究表明,投加了HC-10的强化系统其产氢量比对照高出40.32%。 同时为了获得厌氧产氢菌的高效突变株,分别以产氢菌H-8和H-61为原始菌株进行微波诱变处理,对微波诱变参数进行了优化,考察了突变株的遗传稳定性、产氢特性及耐酸性。菌株H-8经过微波诱变得到5株高产氢突变株HW7、HW33、HW181、HW184、HW195,经多次传代表明HW195是稳定的高产突变株。突变株HW195具有较好的耐酸性,在pH值为2.8时仍能生长。通过间歇发酵实验,其最大产氢量和最大产氢速率分别达到2460 mL/L培养基和27.97 mmol H2/g drycell·h,比原始菌分别提高了50.75%和41.7%。菌株H-61经过微波诱变后选育得到的突变株HW-18,其最大产氢量和最大产氢速率分别达到2190 mL/L培养基和25.86 mmol H2/g drycell·h,比原始菌分别提高了23.03%和31.00%。 为了对比各种诱变方式对产氢菌产氢能力的影响,以厌氧产氢菌H-61为原始菌株,先后经亚硝基胍(NTG)、紫外(UV)诱变,选育得到1株高产突变株HCM-23。在葡萄糖浓度为10 g/L的条件下,其产氢量为3024 mL/L培养基,比原始菌株提高了69.89%;其最大产氢速率为33.19 mmol H2/g drycell·h,比原始菌株提高了68.14%。经过多次传代实验,稳定性良好。其发酵末端产物以乙醇和乙酸为主,属于典型乙醇型发酵。其最适产氢初始pH为6.5,最适生长温度为36 ℃,以蔗糖为最佳碳源。与原始菌株相比,突变株HCM-23的产氢特性发生了改变,如生长延滞期延长,可利用无机氮源等。 From anaerobic activated sludge, 16 strains of hydrogen producing bacteria were newly isolated. One of them named as HC-10 had the highest hydrogen producing capability, under the batch fermentative hydrogen production condition, the maximal hydrogen yield and hydrogen production rate was 2840 mL/L culture and 25.39 mmol H2/g drycell·h. It was identified as clostridium sp.HC-10 by 16S rDNA sequence analysis. Various parameters for hydrogen production, including substrates, initial pH and temperature, have been studied. The optimum condition for hydrogen producing of strain HC-10 were achieved as: initial pH 7.0, temperature 35 ℃, glucose as the favorite substrate, Moreover, using distiller's solubles wastewater as substrate, HC-10 strain was added in the biohydrogen producing system to research the bioaugmentation effection. The results showed that the hydrogen production of bioaugmentation system was 40.32% higher than the noaugmentation system. An anaerobic, hydrogen producing strain H-8 was irradiated by microwave to optimize the microwave mutagenesis condition, and to test the heredity, hydrogen-producing potential and aciduric of the mutants. An aciduric mutant named as HW195 with steady hydrogen-producing capability was obtained, which can grow at pH 2.8. Its capability of hydrogen production was tested in the batch culture experiments. The maximum hydrogen yield and hydrogen production rate was 2460 mL/L culture and 29.97 mmol H2/g drycell·h, which was 50.7% and 41.7% higher than those of the initial strain, respectively. When used the strain H-61 as original strain, a mutant named as HW18 was obtained. The maximum hydrogen yield and hydrogen production rate was 2190 mL/L culture and 25.86 mmol H2/g drycell·h, which was 23.03% and 31.00% higher than those of the initial strain, respectively. The results demonstrated that microwave mutagenesis could be used in the field of hydrogen producing microorganism. The hydrogen producing strain H-61 was used as an original strain which was induced by NTG and UV for increasing and the hydrogen production capability. One of the highest efficient H2-producing mutants was named as HCM-23 with its stable hydrogen production capability. which was tested in the batch culture experiments. With the condition of 10 g/L glucose, its cumulative hydrogen yield and hydrogen production rate was 3024 mL/L culture and 33.19 mmol H2/g drycell·h, 69.89%and 68.14% higher than that of the original strain, respectively. The terminal liquid product compositions showed that the mutant HCM-23 fermentation was ethanol type, while the original strain H-61 fermentation was butyric acid type. Varieties of parameters of hydrogen production fermentation were studied, including time, carbon source, nitrogen source, glucose concentration, glucose utilization, initial pH and incubation temperature had been studied, indicated the optimum condition of hydrogen production for the mutant HCM-23 as initial pH6.5, temperature 36 ℃, and the favorite substrate was sucrose. The hydrogen production characters of the mutant and the original strain were different, such as, the growth lag phase and the utilization of inorganic nitrogen source, etc. This work shows a good application potential of NTG-UV combined mutation in the biohydrogen production. And the hydrogen production mechanism and metabolic pathway should be explored furthermore.

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组特殊自养氨氧化混合种群,表现:无机环境种群生长迅速、生物量高;在一个完全无机的自养生长环境中,不仅保持高氨氧化速率,并出现丰富的异养微生物种群;该种群置于异养、厌氧环境中,迅速表现出产氢特征。对于这样一个特殊的生态体系,研究其共生机理,以及联接这些种群之间的碳源和能源问题,将具有非常重要意义。我们拟从种群特征、细胞表面分泌产物、游离体系产物多糖、蛋白和脂肪酸方面开展研究。 第一部分,自养氨氧化混合种群的基本特征。采用氨氧化培养基,进行种群氨氧化特征研究;采用扫描电镜观察自养混合种群的微观特征;沉降、离心去除微生物种群,分析水相中的总有机碳、糖类等物质;利用LB培养基进行种群的分离、纯化,并采用DGGE手段对微生物种群结构进行分析。结果表明,接入菌种后(2/5000(V/V)),培养液中氨(200mg/L)在3-5天内快速降解;亚硝酸盐与氨氮变化呈负相关趋势,仅有少量硝酸盐含量(< 30mg/L)。氨氧化种群的生物量增长与氨氧化趋势一致,初始生物量7.75 mg/L(蛋白含量),3-5天后生物量快速增长,并达到最高63.06 mg/L(蛋白含量)。电镜图片显示,种群外包裹一层粘液。离心除去菌体后,检测培养液总有机碳和糖的含量,同样表现出与生物量增长相似的特征,分别由初始的3.73、2.35 mg/L,3-5内天迅速增加,并分别达到最大值35.19、27.45 mg/L。经初步分离、纯化并对纯化菌株进行测序,获得了10株异养微生物分别为布鲁氏菌科苍白杆菌属、纤维单孢菌、类芽孢菌属、黄杆菌属、无色杆菌、鞘脂单胞菌、嗜麦芽寡养单胞菌、噬氢菌属、硫红球菌、假单胞菌;DGGE显示,约有20分条离带,我们对其中的两条优势条带进行切割回收测序,鉴定为欧洲亚硝化单胞菌(Nitrosomonas eur)。 第二部分:混合种群自养-异养菌共生的可能机制。在对微生物种群特征初步分析基础上,针对胞外糖类组分可能被微生物代谢分解,我们重点对微生物细胞蛋白质与糖类进行分析。采用超声结合RIPA裂解液裂解,SDS-PAGE电泳分析混合种群总蛋白种类,并通过氨基酸分析仪及红外光谱法分析氨基酸组成及蛋白红外特征。采用超声破碎结合反复冻融对细胞样品进行处理,提取液采用醇沉、Sevage脱氮白,凝胶过滤方法脱盐和分级分离。对提取物的糖分析包括:紫外扫描,红外光谱,核磁共振,单糖组成分析;扫描电镜观察菌群破裂现象。SDS-PAGE分析结果表明:氨氧化种群不同生长阶段都显示出42kD蛋白表达量很高,d4时42kD蛋白表达已经很强,4-7d内一直持续这种过量表达,直到d8后表达开始减弱。说明42kD蛋白可能与氨氧化密切相关。红外光谱分析显示:细胞提取物的特征峰分布在3427.42cm-1、1718.18 cm-1和1681.72 cm-1、1160.07和1086.74 cm-1,分别对应为OH、 C=O、C-O-C基团,表明具有蛋白的典型特征;氨基酸分析显示蛋白中的Gly,Asp,Ala,Glu含量相对较高。 提取物中胞外多糖分离谱图得到不均一组分,共得到6个收集峰;紫外扫描在201-213 nm处有多糖吸收峰,同样表明多糖成分不均一性;多糖红外光谱特征峰主要分别在3400.49 cm-1、2920.28 cm-1、1154.54和1087.52 cm-1,对应OH、-CH2- or CH 、C-O-H or C-O-C等多糖特征基团;多糖提取物核磁共振1H d4.3~5.9之间出现强吸收峰,这是1H中,多糖存在的明显证据,1H NMR中,其中O-乙酰基的甲基上的氢信号为d1.1~1.3之间。糖肟全苯甲酸酯衍生物的HPLC测定中,得到单一的单糖峰,由于时间问题,还未进行更深入的试验;电镜图片显示,种群中的细胞有大量的破裂现象。 实验表明,自养氨氧化混合种群显示出快速的氨氧化速率,氨氧化过程生物量和有机质的增加明显。微生物种群包裹粘液层,并分离纯化出大量的异养菌;去除菌体后的游离培养液中存在有机质(包括多糖)说明无机自养生长体系中存在异养菌生长、繁殖的二次碳源;细胞提取物中蛋白条带数目多、种类丰富;细胞多糖提取物具有明显的多糖特征,以及单糖的存在。结合种群的显微特征和游离体系中的有机质的检测结果,我们认为,无机自养生长体系中,种群细胞生长过程中发生的破裂现象可能是导致大量的蛋白、多糖释放到游离胞外,并成为其他异养菌生长的碳源和氮源。这可能是自养体系中,大量异养菌共生的可能机制,至于是什么原因引起种群生长过程中产生的破裂现象,还有待下一步深入研究。 A group of mixed autotrophic ammonia oxidizing populations, having much biological characteristic tested by concerned personnel for pilot test: Performed rapid population growth and obtained high biomass in inorganic environment; Not only maintained a high rate of ammoxidation, promoted a wealth of heterotrophic microbial populations growth in a totally inorganic and autotrophic growth environment; Placed in heterotrophic and anaerobic environment,had the performance characteristics that could rapidly produce hydrogen.For such a special ecological system, Study its symbiotic mechanism and the connection between these populations of carbon and energy issues, will have a very important significance. We intended from the characteristics of the population, the secretion product of cell surface, free substance in the liquid medium like polysaccharide, protein and fatty acids carrying out research. Part I: The basic features of mixed autotrophic ammonia oxidizing populations . Use inorganic liquid medium, processed study for ammonia oxidation characteristics of the population; we used scanning electron microscopy to get micro-features of autotrophic ammonia oxidizing populations .The medium was carried out settlement and centrifugal then removed the microbial populations, after all of that we analysis the water phase for total organic carbon(TOC), carbohydrate and other substances; Solid ammonia oxidizing medium was adopted to separation and purification of population, DGGE means was for structure analysis of microbial population. The results showed that after the inoculum of bacteria (2 / 5000 (V / V)), ammonia in the culture medium (200 mg / L) was rapid degradation in 3-5 days; ammonia and nitrite have the negative correlation between changes in the trend, then only a small amount of nitrate content (<30mg / L). The biomass growth of ammoxidation population in line with the trend of ammonia oxidation, the initial volume of it was 7.75 mg / L (protein content), in 3-5 days upto 63.06 mg / L (protein content). Electron microscope image showed, the populations were wrapped in a layer of mucus, including the a large number ruptted micorbe , Centrifuge to remove bacteria, then detected the medium for total organic carbon and sugar content, result took on the same characteristics with biomass growth, that were from the initial 3.73、2.35 mg / L respectively, in 3-6 days achieved rapid increase in the maximum to 35.19、27.45 mg / L respectively. After initial separation、 purification ,then processed sequencing to strains purified and got the result that there were 10 heterotrophic microorganisms : Brucella Branch pale bacillus, Cellu lomonas, Bacillus species category, a Flavobacterium, colorless Bacteria, Aeromonas sheath fat, little support maltophilia Aeromonas, macrophages species hydrogen, sulphur-MI, Pseudomonas bacteria spores; DGGE display, there were 20 separation bands approximately. Part II: Mixed populations that autotrophic - heterotrophic bacteria symbiotic mechanism. On the basis of preliminary analysis of microbial population characteristics, aiming at extracellular carbohydrate components might be decomposition by microbial, we focused on microbial cell protein and carbohydrate analysis. Using ultrasound combined with RIPA lysis cracking the cells, SDS-PAGE electrophoresis analysis the total protein species of the population, and through the amino acid analyzer studied the compositions of amino acid and infrared spectroscopy analysis of a protein infrared characteristics. Using ultrasound combined with repeatedly freezing and thawing to treated the cell sample, then took the means that alcohol precipitation, deproteinization by Sevage, gel filtration aimed at desalination and grade separation to deal with the lysates . The extraction of sugar analysis included: UV scanning, IR, NMR, single-sugar composition analysis. SDS-PAGE analysis showed that: 42 kD protein expression was very high at different growth stages of mixed autotrophic ammonia oxidizing populations , on the fourth day, 42 kD protein expression had been very strong, 4-7d, it had continued this excessive expression, then started to weaken after 7 days. 42 kD protein that might be closely associated with ammonia oxidation. Infrared spectral analysis showed that: cell extracts with the characteristic that the peak distribution in 3427.42 cm-1、1718.18 cm-1 and 1681.72 cm-1、1160.07 cm-1 and 1086.74 cm-1 corresponding to OH、C = O、C-O-C Groups which had the typical characteristics of protein; and analysis showed that amino acids including Gly, Asp, Ala, Glu ,the content in the protein is relatively high. Exopolysaccharide in the extracts had the separation map that it was uneven, received a total of six collection peaks by the detection mode of phenol-sulphruic acid method ; ultraviolet scan in the 201-213 nm department had polysaccharide absorbing peak, the same ingredients that polysaccharide heterogeneity; infrared polysaccharide spectral characteristics of the main peak at 3400.49 cm-1, 2920.28 cm-1, 1154.54 and 1087.52 cm-1, corresponding OH,-CH2-or CH, C-O-H or C-O-C;and other characteristics of polysaccharide group; 1H NMR of polysaccharide extract appeared absorption peak between d4.3 ~5.9, which is the apparent evidence of polysaccharide, In 1H NMR, the hydrogen signal of one of O-acetyl was between 1.1 to 1.3. The determination of Sugar oxime whole benzoate derivatives by HPLC, there was a single-sugar peak, as a matter of time, yet more in-depth test. Summary: Mixed autotrophic ammonia oxidizing populations show us that it had the ability in ammonia oxidizing and it was great, organic matter and biomass increased significantly in the process of ammonia oxidation. Microbial populations was wrapped up slime layer, the phenomenon of cell breakdown obviously, and there were a lot of separation and purification of the heterotrophic bacteria; a lot of organic matter (including polysaccharides)remined in the medium that removal of cell indicated the inorganic system existed secondary carbon sources that could be used by the heterotrophic bacteria ; there were a large number proteins bands of cell extract, rich variety; cell extracts of polysaccharide had obvious characteristics of polysaccharide, and the existence evidence of single-sugar. Combined population of microscopic characteristics and free of organic matter in the test results, we believe that the health of inorganic system, population growth occurred in the course of the breakdown of the phenomenon is likely to lead to a lot of protein and polysaccharide released into the extracellular free, And other heterotrophic bacteria use them to the growth as carbon and nitrogen. This may be autotrophic system, the large number of heterotrophic bacteria symbiotic mechanism.

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毛壳菌属很多种类具有重要生防价值,其生防机理包括对植物病原真菌的重寄生作用、诱导植物产生抗病性、产生抗真菌活性的次生代谢产物等。迄今,学界对毛壳菌的研究主要集中在毛壳菌的生防机理,毛壳菌活性次生代谢产物的分离等方面。本研究致力于产抗生素的毛壳菌的种间原生质体融合,从产抗生素毛壳菌菌株的筛选开始,进而对产抗生素的角毛壳菌进行诱变选育,最终用产不同抗生素的角毛壳菌与球毛壳菌进行种间原生质体融合。主要有以下五方面研究结果。 1、毛壳菌抗真菌活性物质产生菌株的筛选:不同毛壳菌菌株发酵液采用琼脂扩散法对植物病原真菌进行抑菌活性试验,结果显示,菌株CH08和CH23的发酵液对芒果炭疽、苹果炭疽和马铃薯晚疫菌具有抑制作用。菌株CH16和CH17的发酵液对芒果炭疽菌、苹果炭疽菌有抑制作用。菌株CH21发酵液对辣椒炭疽菌和西瓜枯萎菌有抑制作用。经形态学研究,菌株CH08、CH16、CH17和CH23鉴定为球毛壳菌,菌株CH21鉴定为角毛壳菌。对角毛壳菌与球毛壳菌菌株发酵液抑菌谱比较,发现角毛壳菌与球毛壳菌发酵液具有明显不同的抑菌谱,表明角毛壳菌与球毛壳菌产生不同的抗真菌活性物质。 2、角毛壳菌(CH21)和球毛壳菌(CH08)原生质体制备和再生条件研究:考察了菌龄、酶浓度、稳渗剂及其浓度、酶解温度、酶解时间及再生培养基对原生质体制备和再生的影响。用菌龄为生长54 h的角毛壳菌菌丝,以0.06 M磷酸缓冲液(pH6.0)配制成含蜗牛酶15 mg/ml、溶壁酶10 mg/ml、蔗糖0.6 mol/L的酶解液,30℃酶解1.5 h,原生质体释放量2.02×107个/g;以PDA为再生培养基,0.7 mol/L的蔗糖再生稳渗剂,再生率可达51.45%。用菌龄为生长48 h的球毛壳菌菌丝,以0.06 M磷酸缓冲液(pH6.0)配制成含蜗牛酶15 mg/ml、溶壁酶10 mg/ml、蔗糖0.6 mol/L的酶解液,30℃酶解1 h,原生质体释放量达1.57×108个/g;以PDA为再生培养基,0.7 mol/L的蔗糖为再生稳渗剂,再生率可达41.48%。 3、角毛壳菌(CH21)原生质体紫外诱变选育:以CH21为出发菌株,制备原生质体进行紫外诱变,诱变条件为:15 w紫外灯,距离30 cm,照射90 s,致死率80%~85%。建立了诱变菌株初筛的双层平板筛选模型。经平板初筛和摇瓶复筛,获得一株突变菌株CH21-I-402,其发酵液抑菌活性较出发菌株提高18.3%。 4、抗性标记菌株的获得:菌株CH21-I-402和CH08抗生素药敏试验表明, CH21-I-402菌株对潮霉素有抗性、对G418(Geneticin)敏感,菌株CH08对潮霉素和G418都敏感。根癌农杆菌EHA105介导的新霉素磷酸转移酶基因转化球毛壳菌,经PCR检测,新霉素磷酸转移酶基因成功转化进菌株CH08-GR70,CH08-GR120。转化子对G418抗性提高3~4倍,对潮霉素仍然比较敏感。 5、以G418和潮霉素抗性为筛选标记的原生质体融合与融合菌株AFLP分析:制备角毛壳菌CH21-I-402和球毛壳菌CH08-GR70原生质体,以35%的PEG6000为助融剂进行原生质体融合,以65 μg/ml的潮霉素和60 μg/ml G418为抗性筛选标记,获得46个再生菌株。再生菌株连续传代5代后,再生菌株表现出多种形态类型。利用AFLP技术对再生菌株及亲本菌株基因组DNA分析表明,再生菌株PF1、PF26为融合菌株。抑菌活性测试表明,融合菌株PF26发酵液对芒果炭疽菌和苹果轮纹菌有强的抑制作用,且抑菌活性比亲本球毛壳菌明显提高。 Chaetomium spp. have great potentials as biocontrol agents against a range of plant pathogens on the basis of its mycoparasitism, induced plant disease resistance, production of antifungal metabolites, and so on. Previous researches on C. spp. mostly focused on the mechanisms of its biocontrol and the isolation of secondary metabolites. In this study, screening antifungal C. spp., mutation breeding of C. cupreum and interspecies protoplast fusion between C. cupreum and C. globosum were carried out, respectively. The corresponding results are as follows: Firstly, among more than 40 C. spp., the strains produced anti-fungal antibiotics were screened by agar diffusion experiments. Results showed that both CH08 and CH23 had inhibition against Colletotrichum gloeosporioides, Cladosporium fulvum, and Phytophthora infestans. Both CH16 and CH17 had inhibition against Colletotrichum gloeosporioides and Cladosporium fulvum. In addition, CH21 exhibited anti-fungal activity against Fusarium oxysporum f. sp niveum and Colletotrichum capsici. Furthermore, CH08, CH16, CH17 and CH23 were identified as C. globosum, CH21 was proved to be C. cupreum based on morphology. The comparison of the anti-fungal spectrum between C. cupreum and C. globosum, showed they could produce different antibiotics. Secondly, specified protocols for preparing and regenerating protoplasts from mycelia of C. cupreum CH21 and C. globosum CH08 were studied. The effects of the age mycelia, the concentration of enzyme, digestion temperature and time, kinds of osmotic stabilizer and regeneration medium on protoplasts preparation and regeneration were all optimized, respectively. In one protocol, with 15 mg/mL snailase, 10 mg/mL lywallzyme, 0.6 M sucrose, in 0.06 M phosphate buffer (pH6.0), and digested for 1.5 h at 30 ºC, 2.02×107 protoplasts from each gram mycelia were obtained from cultures of C. cupreum CH21 grown in potato dextrose broth (PDB) medium for 54 h. And when 0.7 M sucrose was used as osmotic stabilizer in the regeneration medium OPDA (potato dextrose agar with osmotic stabilize), the regeneration efficiency of protoplasts was 51.45%. In another protocol, with 15 mg/mL snailase, 10 mg/mL lywallzyme, 0.6 M sucrose, in 0.06 M phosphate buffer (pH6.0), and digested for 1 h at 30 ºC, 1.57×108 protoplasts from each gram mycelia were obtained from cultures of C. globosum CH08 grown in PDB for 48 h. And when 0.7 M sucrose was used as osmotic stabilizer in the regeneration medium OPDA, the regeneration efficiency of protoplasts was 41.48%. Thirdly, the mutagenesis conditions and secondary screening model of C. cupreum CH21 were explored. An 80% to 85% death rate could be achieved when the protoplasts of C. cupreum CH21 were irradiated by 15 w UV lamp from 30 cm distance for 90 s. In addition, the doublelayer plate’s method for the primary screening of high-producing antibiotics strains was established. A high yielding antibiotic mutant CH21-I-402 was obtained through the primary screening on plate and the secondary selection in Erlenmeyer flask, compared to the original CH21 strain, the antifungal activity of the mutant CH21-I-402 was increased by 18.3%. Fourth, the sensitivity to antibiotics of both C. cupreum CH21-I-402 and C. globusm CH08 was detected. Results showed C. cupreum CH21-I-402 was sensitive to G418 (Geneticin) (Gs) and resistant to Hygromycin B(Hr), and C. globusm CH08 was sensitive to both G418 (Geneticin) (Gs) and Hygromycin B(Hs). At the same time, neomycin phosphotransferase II (npt II) gene was transformed into C. globusm CH08(Gs, Hs) mediated by Agrobacterium tumefaciens EHA105, and the npt II gene was verified by polymerase chain reaction in resistance to G418 strains CH08-GR70 and CH08-GR120. The transformants still showed sensitive to Hygromycin B(Hs). Finally, a selection system for hybrids was set up by interspecies protoplast fusion between C. cupreum and C. globusm using dominant selective drug resistance markers. At first, protoplasts of C. cupreum CH21-I-402 (Hr, Gs) and C. globusm CH08-GR70 (Hs, Gr) were prepared, then the protoplasts were fused in the presence of 35% polyethylene glycol 6000 and regenerated on OPDA medium with 65 μg/ml Hygromycin B and 60μg/ml G418, at last 46 colonies with Hr and Gr were obtained. Even after 5 generations’ subculture, most of the colonies displayed significant difference in taxonomic characteristics with their parental strains. Regenerated strains PF1 and PF26 were confirmed as fusants by amplified fragment length polymorphisms analysis with the genomic DNA as the model. PF26 showed higher inhibitory activity against Colletotrichum gloeosporioides and Macrophoma kuwatsukai than that of the parental strain C. globusm.

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猪场废水COD浓度高、氨氮浓度高、悬浮物浓度高,已成为农村面源污染的主要来源,并严重威胁到农村饮用水安全。猪场废水氨氮浓度高、处理难度大,如何采用经济高效的方法,去除氨氮使其达到排放标准,一直是猪场废水处理中面临的重要难题。 厌氧氨氧化是近年受到国内外水处理研究者广泛关注的新型生物脱氮技术,具有不需要外加有机碳源、节省供氧量、降低能耗等优点。虽然国内外研究者对厌氧氨氧化过程的脱氮机理、厌氧氨氧化菌的生理生化特性等进行了多方面的研究,但已有的报道大多以模拟废水为研究对象,以猪场废水为研究对象的报道,在国内外文献中极少有报导。 本论文以猪场废水为主要研究对象,考察了猪场废水的亚硝化过程、厌氧氨氧化的启动过程,并对亚硝化和厌氧氨氧化联合用于猪场废水脱氮进行了探索。 1.论文首先研究了猪场废水的亚硝化过程,考察了废水水质和主要运行条件对亚硝化过程的影响。实验表明:(1)亚硝化阶段反应时间为8到10h时,出水中氨氮和亚硝酸盐浓度比可达到1:1~1:1.23,满足厌氧氨氧化反应对二者比例的要求;达到前述要求时,氨氮去除率达到58.3~65.6 %,亚硝化率在整个过程均保持在97 %以上,COD去除率在59.2~68.6 %;(2)曝气量(溶解氧)对亚硝化过程影响显著,随着曝气量增大,达到厌氧氨氧化要求的氨氮与亚硝酸盐氮浓度比例所需水力停留时间τ越短,pH出现明显下降的时间越短;(3)τ对应的pH在7.8~8.1之间,无需进行pH调节即可满足厌氧氨氧化反应对pH的要求;(4)氨氮和COD降解过程遵循一级反应动力学,氨氮和COD降解的速率常数分别为0.0656~0.0724 1/h和0.0491~0.0664 1/h。 2.在进行亚硝化过程研究的同时,以模拟废水为试验对象,进行厌氧氨氧化启动研究。以反硝化污泥和养殖厂储水池厌氧底泥的混合污泥作为接种污泥,历时大约100天,培育出具有厌氧氨氧化活性的污泥,氨氮和亚硝酸盐氮最高进水浓度分别为223.8 mg/L和171.4 mg/L,去除率最高分别达48%和41.5%,此时二者消耗比例为1.33:1。 3.在猪场废水的亚硝化研究完成和厌氧氨氧化过程初步启动成功后,在模拟废水中逐步加入猪场废水的亚硝化处理出水,逐步实现亚硝化和厌氧氨氧化的组合。亚硝化出水添加到厌氧反应器后,厌氧氨氧化反应仍可继续进行,且去除效率逐步提高。研究发现添加的亚硝化出水中携带的亚硝化细菌在厌氧氨氧化菌膜外层生长并累积,增加了厌氧氨氧化反应基质的传质阻力,妨碍了厌氧氨氧化效率的提高。 4.亚硝化-厌氧氨氧化实际工程应用探索中,生物接触氧化池可在有效去除废水中的有机物的同时实现亚硝化,出水中氨氮和亚硝酸盐比例平均为1.10,可满足后续厌氧氨氧化的要求;在适宜的进水浓度和温度下,ABR池出现了厌氧氨氧化启动的迹象;研究同时发现,水质的波动和气温的变化是工程中影响厌氧氨氧化菌活性的重要因素。 论文的主要创新点在于:(1)以猪场废水为研究对象,以实现厌氧氨氧化为目标,对亚硝化过程进行了比较详细的考察,获得了亚硝化出水满足厌氧氨氧化要求的工艺条件,通过对其COD和氨氮降解过程的考察,得出亚硝化阶段COD降解和氨氮去除的动力学模型;(2)对亚硝化-厌氧氨氧化处理猪场废水进行了探索,确立了影响其污染物去除率稳定的重要因素。 论文的上述研究成果,为厌氧氨氧化技术的实用性研究提供理论依据。 Piggery wastewater, which is characterized by high concentration of COD、ammonium and suspend substance, has become a most important source of non-point source pollution and also severely threats drinking water security in rural area. How to discharge piggery wastewater with the ammonium concentration meeting standard by economical and effective method? This is the most urgent problem in piggery wastewater treatment. As a new biological nitrogen removal technology, Anammox process has been paid more and more attention by researchers all over the world. Anammox has advantages of no need of organic carbon addition, low oxygen consumption and energy consumption. Plenty of investigations have been carried out to the mechanism, physiological and biochemical characteristic of bacteria about Anammox. Most of researches focused on synthetic wastewater, there is rare report about its application in piggery wastewater. In this paper,experimental studies were performed to investigate Sharon process in treatment of piggery wastewater,the start up process of Annammox using synthetic wastewater were studied, the feasibility of applying Sharon-Anammox process in the nitrogen removal of piggery wastewater was evaluated. 1. Sharon process of piggery wastewater was firstly investigated to analyze the effects of water quality and main running parameters, which meet the NH4+-N to NO2--N ratio requirement of successive Anammox. Results showed: (1)During Sharon Process,after 8~10 hours’ reaction the NH4+-N to NO2--N ratio in effluent reached 1:1.0~1:1.23, when the removal percentage of NH4+-N was 58.3~65.6 %, a semi-nitration rate of above 97 % was achieved during the process; meanwhile 59.2~68.6 % of the COD was also removed. (2)The aeration rate(oxygen) had obvious effect on the hydraulic retention time(τ) which met the NH4+-N to NO2--N ratio requirement of Anammox. As aeration rate increased, the hydraulic retention time(τ) was shortened. (3) The pH corresponding to τ was between 7.8 and 8.1, thus it needed no artificial adjustment. (4) The reduction of ammonia and COD followed the first-order reaction kinetics. The velocity constants of ammonia and COD were 0.0656~0.0724 1/h and 0.0491~0.0664 1/h, respectively. 2. The startup of Anammox process using the artificial wastewater was performed simultaneously with Sharon. The aim was to investigate the running parameters of Anammox and make foundation for the combination stage. By using the mixture of denitrifying sludge and anaerobic sludge in tank of the breeding factory, sludge of Anammox activity was cultivated in UASB after 100 days. The removal percentage of NH4+-N and NO2-N were up to 48% and 41.5%, respectively, when the NH4+-N and NO2-N influent concentration were 223.8 mg/L and 171.4 mg/L, respectively, the NH4+-N and NO2-N removal rate was 1.33:1. 3. After investigation of Sharon and startup of Anammox, effluent of Sharon process was added into the synthetic wastewater to combine Sharon and Anammox step by step. It took some time after the addition of Sharon effluent that Anammox reaction continued and the removal rate kept increasing. It indicated that nitrifying bacteria were carried by the Sharon effluent cumulated in the outer layer of Anammox. This enhanced transfer resistance of Anammox reaction and the increasing removal rate was restrained. 4. In the bio-contact oxidation pond of practical project, Sharon process were carried out successfully and organic compounds were removed effectively. An average NO2-N/ NH4+-N rate of 1:1.0 was achieved in the effluent, which met the requirement of successive Anammox. Under condition of suitable influent concentration and temperature, there was evidence that Anammox could start up in ABR. The variety of wastewater and temperature had great affects on Anammox activity in practical engineering. Innovation of this paper: (1) The Sharon process for treating piggery wastewater was discussed in details. Technological parameters that met requirement of Anammox were obtained. The dynamic models of COD and ammonium removal in the process were educed. (2) Sharon-Ananmmox for treatment of piggery wastewater was investigated, and the primary influencing factors was studied. This paper could be a theoretical consult for research of Anammox utility.

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一体化反应器由于投资少、占地小、管理运行方便等优点而备受青睐。但现有的一体化反应器大都适用于处理中低浓度废水,耐受负荷普遍偏低。本课题研制出新型高效的厌氧好氧一体化生物反应器,旨在通过反应器结构优化、高效微生物载体研制、配合高效微生物菌剂技术处理中高浓度有机废水,实现高效和低耗,降低设备造价,提高反应器运行稳定性。 首先开展了菌剂对废水的适配试验。采用15种不同的微生物菌剂,以葡萄糖配水、中药提取废水、啤酒废水、氨氮配水为基质,分别测定了微生物菌剂的耗氧速率和厌氧比产甲烷速率,以其为指标比较了各菌剂对废水的适配性。根据结果选择活性高的14#、8#、10#菌剂,在试验室进行了菌剂对废水的连续处理试验,取得良好的处理效果,为菌剂在厌氧好氧一体化生物反应器的小试、中试中的应用奠定了基础。 经小试研究后,又对厌氧好氧一体化生物反应器进行了处理发酵废水的中试研究。试验结果表明,反应器启动快,系统有机负荷2.72 kgCODm-3d-1时整个反应器去除率保持在84.5%~93.19%,在30多天内一次启动成功。冲击负荷试验中,系统总有机负荷最高可达到8.88 kgCODm-3d-1,系统去除率稳定在88.10%~96.88%,说明反应器处理效率高,抗冲击能力强。稳定运行期间,COD去除率可达90%以上,各项指标都能达到国家排放标准。 此外,对反应器配套系统高效菌剂、高分子复合颗粒载体进行了研究。结果显示,菌剂与反应器适配良好,各功能区形成了丰富、高活性的微生物,厌氧区颗粒污泥TS高达83.9 gL-1,VS/TS为56.9%~57.4%,比产甲烷活性为280~350 mLCH4 gvss-1d-1;好氧区固定化微生物TS高达1.921 gL-1,VS/TS为94.02~94.30%。对载体性能的研究表明,此高分子复合颗粒载体密度适中,易于流化,不易流失;粗糙多空,易于挂膜;且无生物毒害作用,稳定安全,是一种优良的生物载体。反应器各功能区对废水的降解过程分析,说明了反应器、菌剂、载体适配良好,在其协同作用下,实现了污染物的高效降解。 The integrated reactors were popular because of their characteristics such as little investment, small occupation of land, convenient of manage and running etc. But the present integrated reactors were mostly applied for treating wastewater of low concentration, the load tolerance was generally on the low side. A new type integrated anaerobic-aerobic bio-reactor was developed, which was conducted to treating organic wastewater of middle or high concentration by optimization of reactor structure, development of efficient microbe carrier and adaptation of high active microbial blends, to achieve high efficiency and low consume, reduce equipment cost, enhance running stabilization of reactor. The adaptability test of microbial blends on different wastewater was carried on firstly. Oxygen consumption rate and anaerobic specific activity of methane producing of 15 different microbial blends were measured separately taking glucose artificial wastewater, Chinese herb extracting wastewater, brewery wastewater and ammonia nitrogen artificial wastewater as substrate, by which the adaptabilities of different microbial blends to wastewater were compared. According to the results high active microbial blends 14#, 8# and 10# were selected and used in the continuous treatment of wastewater in the laboratory and had obtained good effect, which had laid a foundation for application microbial blends to small scale test and pilot test of integrated anaerobic-aerobic bio-reactor. After the small scale test, the pilot test of the integrated anaerobic-aerobic bio-reactor treating fermentation wastewater was carried on. The test results showed fast initiation of the reactor. When system organic load reached 2.72 kgCODm-3d-1the COD removal rate of the reactor was stable between 84.5%~93.19% and it initiated successfully in more than 30 days at a time. In the load shock test the maximum organic load of system could reach to 8.88 kgCODm-3d-1 and the COD removal rate could be stable between 88.10%~96.88% which indicated that the reactor was efficient for treating wastewater and had strong resistance to shock load. At stable running period the COD removal rate of the reactor was over 90% and each index of wastewater could reach to the national discharge standards. In addition, the high active microbial blends and the macromolecule compound granule carrier, the matching system of the reactor was studied. It showed that the microbial blends adapted well to the reactor and abundant and high active microbes were formed in each functional field. The TS of granule sludge in anaerobic field was as high as 83.9 gL-1, the VS/TS was 56.9%~57.4%, the specific activity of methane producing was 280~350 mLCH4 gvss-1d-1. And the TS of immobilized biological granule was as high as 1.921 gL-1, the VS/TS was 94.02%~94.30%. Study on the carrier showed that the self-made macromolecular compound granule carrier was moderate of density, easy of fluidization, unease of running off, rough and porous, easy of films fixation, no bio-toxic, stable and safe, was a kind of superior carrier. Analysis of degradation process in each functional field confirmed the reactor, microbial blends and carriers were in good adaptation and wastewater was decontaminated by their cooperation.

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本文介绍了从厌氧间歇膨胀光合反应器内的活性污泥中分离并鉴定的泥生绿菌(Chlorobium limicola Nadson)S1,它属严格厌氧光能自养型细菌,在有硫化物和少量碳酸氢盐存在下,有广泛利用有机物的能力,它的最适生长温度为28-30℃,最适生长PH为6.5-7.0,且含有氢化酶。因此,它能与甲烷发酵菌共存而共同作用,达到废水净化之目的。通过光照(2#反应器)和黑暗(1#反应器)对比实验,表明了在光照条件下即有泥生绿菌S1存在下,反应系统能更好地降低CODcr、BOD5 和提高CH4 含量,在四个负荷段的运行中,2#反应器在后三个负荷段的甲烷含量能稳定在91.6%而1#反应器为87%,2#反应器的二氧化碳含量为4.5%而1#反应器为8.8%,于28.35g/l.d的负荷下,2#反应器CODcr去除率达83.4%,BOD去除率达74.53%,分别较1#反应器高10.8%,6.4%。COD去除率提高了14%,BOD去除率提高了9.3%。本试验的试验条件为:白天自然光照,晚上电源光照,光照强度为1000-2500lux,通过连续动态运转,并以恒定的流速将废液注入反应器中,进水PH控制在6.5-7.2,反应器厌氧,恒温室温度控制在30±1℃。为使整个试验中同一水质条件下进行,进水采用化学合成培养基。This paper reports a Chlorobium Liwicola S1's isolation and identification. It is a strictly anaerobic and photosynthetic autotrophic bacterium. Along with sulfidedepondent CO2 assiwilaton,a few simple organic compounds can be photoassimilated. Acetate is most effectively used. Its best conditons of growth are 28-30℃,PH 6.5-7.0, and it contains hydrogenase. So it can live with methanefermentative bacteria in order to treat wastewater. At the same time, the treatment of wastwater using Chlorobium Limicola S1 with methane-fermontative bacteria under dark anaerobic and light anaerobic conditions is studied. In contrast with 1# reactor-darken, 2# reactor-illuminated can lossen wastewater's CODcr, BOD5 and on hance CH4 content better. In the test, 2# reactor's CH4 content is stable at 91.6%, but 1# reactor's is 87%. The CO2 content of 2# reactor is 4.5%, but 1# reactor's is 8.8%. When the load of teatment is 28.35g/l.d, the COD removal effficiency is 83.4% and the BOD removal efficiency is 74.53% in 2# reactor. They are separately 10.8%, 6.4% higher than 1# reactor's.

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本文从新鲜大熊猫粪便和实验室保存的沼气发酵富集物中筛选得到 4 株厌氧纤维素分解菌B5、C3、D3-2、D4-1,利用这4 株菌预处理秸秆,然后将预处理后的秸秆用本实验室保存的厌氧产氢菌来发酵进行生物产氢。同时还比较研究了:○1 用1% H2SO4、25% NH3 · H2O和12% NaOH对秸秆进行化学预处理;○2 用厌氧纤维素分解菌对秸秆进行生物预处理;○3 化学与生物组合预处理对秸秆发酵生物产氢的影响。实验结果表明:12% NaOH和生物组合预处理后的秸秆发酵产氢效果最好,其产氢量为21.04 mL g-1,是未经预处理秸秆的75 倍;最高氢气浓度为57.3%,是未经预处理秸秆的96 倍;其产氢的最适pH 为4.5 ~ 6.0,最佳底物浓度为45 ~ 55 g L-1;其发酵过程中的挥发性脂肪酸(VFAs)以乙酸和丁酸为主。 本实验筛选到的 4 株厌氧纤维素分解菌株中,B5 和D4-1 在降解纤维素的同时还具有直接以纤维素为底物产氢的功能,因此本文分别对菌株B5 和D4-1 以及二者的组合菌株B5+D4-1 直接利用秸秆为基质发酵生物产氢做了初步探索研究。结果发现:组合菌株发酵产氢的效果以及对秸秆纤维素和半纤维素的降解率要比单菌株好。菌株B5+D4-1 发酵,秸秆的产氢量为11.4 mL g-1,分别是B5 和D4-1 单菌株的1.6 倍和3.1 倍;组合菌株B5+D4-1 发酵的最大氢气浓度为31.6%,分别是B5 和D4-1 单菌株的1.3 倍和2.4 倍。在发酵过程中,组合菌株B5+D4-1 对秸秆纤维素和半纤维素的最高降解率分别为35.0%和11.8%,分别是菌株B5 的1.2 倍和1.1 倍,是菌株D4-1的1.5 倍和1.3 倍。菌株B5,D4-1 以及组合菌株B5+D4-1 发酵过程产生的挥发性脂肪酸(VFAs)均以乙酸为主。菌株B5 单独发酵过程中只检测到乙酸和丁酸,菌株D4-1 单独发酵以及组合菌株B5+D4-1 发酵过程检测到有乙醇、乙酸和丁酸。 The fermentative bio-hydrogen production by anaerobic hydrogen bacteria preserved in our laboratory from the straw which had been pretreated by four anaerobic cellulolytic decomposition strains of B5, C3, D3-2, D4-1 which were isolated and screened from giant panda’s excrement and biogas fermentation enrichments conserved in our laboratory was studied. Besides, the impact of chemical(1% H2SO4、25% NH3·H2O and 12% NaOH), biological (cellulolytic strains of B5, C3, D3-2, D4-1) and chemical-biological combination pretreatment on bio-hydrogen production from straw by fermentation was also comparatively studied. The experiments showed that the best results of bio-hydrogen production were obtained from the straw with 12% NaOH-biological combination pretreatment method, its capability of bio-hydrogen production was 21.04 mL g-1, which was 75 times higher than the straw without pretreatment; the maximum concentration of H2 was 57.3%, which was 96 times higher than the straw without pretreatment; its optimum pH range was 4.5 ~ 6.0, and its optimum range of substrate concentration was 45 ~ 55 g L-1; In the process of fermentation, the main composition of VFAs were acetate and butyrate. Among the four strains of B5, C3, D3-2, D4-1, B5 and D4-1 have the function of hydrogen-producing by cellulose used as substrate when it decompose cellulose, so the preliminary exploration and research on fermentative bio-hydrogen production by B5, D4-1 and B5+D4-1 which directly used straw as substrate was carried out. The results showed that the combination strains of B5+D4-1 was strikingly better than either B5 or D4-1 strain in the fermentative hydrogen production. The hydrogen-production capability of B5+D4-1 was 11.4 mL g-1 which was respectively 1.6 times and 3.1times higher than B5 and D4-1; the maximum hydrogen concentration of B5+D4-1 was 31.6% which was respectively 1.3 times and 2.4 times higher than B5 and D4-1. In the process of fermentation, the maximum degradation rate of cellulose and hemicellulose in straw was respectively 35.0% and 11.8% by B5+D4-1, which was 1.2 times and 1.1 times higher than B5, and was 1.5 times and 1.3 times higher than D4-1 respectively. The Volatile Fattty Acids(VFAs) generated in the process of fermentation with strains of B5, D4-1 and B5+D4-1 were all mainly acetate. Acetate and butyrate were detected in the process of fermentation with B5, ethonal, acetate and butyrate were detected in the process of fermentation with D4-1 and B5+D4-1.

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本文从成都龙泉垃圾填埋场和宜宾造纸厂分离到耐酸性能优良的高温产甲烷菌RY3和中温产甲烷菌SH4,并将其与实验室现有的利用不同底物的产甲烷菌配伍组合成了复合菌剂。采用活性污泥作为固体附着物,研制出了固体产甲烷菌复合菌剂。 菌株RY3的pH耐受范围为5.5~10.5,最适生长pH 6.0~8.0。菌株RY3为革兰氏阳性,长杆状,多数单生,不运动;菌落浅黄色,形状近圆形;利用H2+CO2或甲酸盐作为唯一碳源生长,不利用乙酸盐,对氯霉素非常敏感。该菌最适生长温度为55℃~65℃,最适NaCl浓度为0~2%。根据形态和生理生化特性及16S rDNA序列分析将其初步定为热自养甲烷热杆菌(Methanothermobacter thermautotrophicus)。添加RY3菌液与仅添加厌氧污泥作为接种物相比一周内可使达到最大产甲烷速率所需时间缩短三分之二,甲烷总产量提高约1.8倍。菌株SH4的生长pH范围5.5~9.5,其对酸碱具有良好的适应性,培养3天后,在初始pH值为6.0~8.0的培养基中甲烷产量相差不大,且基本达到最大产量。SH4革兰氏染色阳性,短杆状,多数单生,不运动;菌落近圆形,微黄;利用H2+CO2或甲酸盐作为唯一碳源生长,不利用乙酸盐,对氯霉素非常敏感。SH4最适生长pH 为7.0,最适生长温度为35℃,最适NaCl浓度为0~1.5%。实验表明,添加SH4菌液与仅添加厌氧污泥作为接种物相比可使产甲烷启动时间缩短三分之一,甲烷总产量亦有大幅提高。从形态和生理生化特征以及16S rDNA序列分析表明SH4为嗜树木甲烷短杆菌(Methanobrevibacter arboriphilus)。 以活性污泥为附着物,与培养基和菌种经搅拌后厌氧发酵可得产甲烷菌固体复合菌剂。固体复合菌剂的pH耐受范围为5.5~9.5,温度耐受范围为15℃~65℃,表明其对环境的适应性较强。以猪粪为底物进行厌氧发酵,接种复合菌剂进行试验,以接种实验室长期富集的产甲烷厌氧污泥作为对照,在20℃时,发酵甲烷浓度与对照基本一致,但每日产气量优于对照,第15天时接种复合菌剂的发酵瓶每日产气量是对照的1.59倍;50℃时达到最大甲烷含量所需时间比对照缩短三分之二,三周内总产气量约为对照的2.7倍,甲烷总产量约为2.8倍。以不加接种物为对照,接种复合菌剂20℃时发酵甲烷含量达到50%约需2周,对照2周内甲烷含量最高仅为4.3%;50℃时接种复合菌剂发酵仅需约1周甲烷含量便可达50%,对照则至少需要2周。 In this paper, high-temperature Methanogen RY3 and middle-temperature SH4 were isolated from Chengdu Longquan refuse landfill and Yibin paper mill. They could be used to make compound inoculum that producing methane with the existing Methanogens utilized different substrate. With using anaerobic activated sludge be solid fixture, the process had been designed to produce solid compound inoculum. Strain RY3 possessed excellent capacity of acid and alkali-tolerant. The pH-tolerant scale of RY3 was 5.5~10.5 and its optimum pH value for growth was 6.0~8.0. RY3 was G+, long-rod shape, monothetic and nonmotile, the colony was pale yellow with suborbicular-shape. Formate or H2+CO2 but not acetate was utilized by RY3 as sole C-source, and it was very sensitive to chloramphenicol. Besides, strain RY3 grew fastest at 55℃~65 and 0℃~2% NaCl. Characteristics of modality and physiology with sequence analysis of the 16s rDNA gene of strain RY3 preliminarily showed that it was Methanothermobacter thermautotrophicus. The experiments indicated that the time which began to produce methane with the highest velocity could be shortened two third by adding RY3 in one week, and the total methane production also was 1.8 times than before. Strain SH4 possessed wide scale of growing pH(5.5~9.5)and excellent ability of acclimatizing itself to acid-alkali. The methane production had no apparent difference among those cultivated in different initial pH(6.0~8.0)after three days and equaled to the maximum production basically. Cells of SH4 were G+, short-rod sharp, monothetic and nonmotile. The colony was pale yellow with suborbicular-shape. Formate or H2+CO2 but not acetate was utilized by SH4 as sole C-source, and it was very sensitive to chloramphenicol. Besides, it grew fastest at pH 7.0,55 ℃~65 and 0℃~2% NaCl concentration. The experiment indicated the time that began to produce methane could be shortening one third by adding SH4. And the total methane production also rose apparently. Characteristic of modality and physiology with sequence analysis of the 16S rDNA gene of strain SH4 demonstrated it was Methanobrevibacter arboriphilus. The activated sludge was utilized as fixture, mixed with culture medium and inocolum, that the solid compound inoculum could be produced by anaerobic fermentation. The compound inoculum could grow between pH 5.5~9.5, 15℃~65. It demonstrated the compound inoculum ha℃ve great ability of adapting to circumstance. In the experiment that making pig manure be substrate and taking the anaerobic sludge producing methane that cultured in long term in laboratory to be comparison, the concentration of methane in fermentation added compound inoculum almost equal to the comparison at 20℃, but the volume of gas production could be a little higher. The gas production everyday inoculated compound inoculum was 1.59 times to comparison. The time that the concentration of methane to maximum could be shortening by two third by adding compound inoculum, and the total gas production was 2.7 times to comprison while the total methane production was 2.8 times. If take the no inoculum be the comprasion, anaerobic fermentation added compound inoculum made the concentration of methane to 50% in 2 weeks but the comparison only to 4.3% at 20℃. The time that the concentration of methane to 50% by adding compound inoculum only need 1 week, but the comparison need 2 weeks at 50℃.

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制革行业是轻工行业中仅次于造纸业的高耗水、重污染行业,作为劳动密集型行业,在解决大量人口就业问题的同时,也对所在地区环境造成了严重污染。目前我国制革行业每年排放废水8,000~12,000万吨,废水中含铬约3,500 t,SS为1.2×105 t,COD为1.8×105 t,BOD为7×104 t,对水体污染严重。 本研究在对厌氧酸化工艺进行研究、一级好氧处理段进行工艺比选研究的基础上,获得了匀质调节—SBBR—BAF的生物处理工艺,并依托该工艺进行了生物强化处理的研究,考察了菌剂的强化运行效果及其处理水回用的可行性。 研究表明,在进水COD>3,000 mg/L,厌氧酸化具有很好的抗冲击作用,保证了好氧工艺出水COD<200 mg/L;在进水COD<3,000 mg/L,可只通过好氧处理实现出水COD<200 mg/L。厌氧酸化停留时间选择不当,会导致厌氧出水硫化物浓度升高,严重影响好氧系统,会使好氧活性污泥因中毒而解絮。 研究表明,当进水COD为2,000~2,500 mg/L,NH4+-N为130~146 mg/L时,COD、NH4+-N去除率SBBR分别为93.8%~96.6%和14.5%~55.9%,SBR分别为88.8%~94.9%和13%~50.7%,表明SBBR优于SBR。同时,研究发现SBBR污泥增长率为0.05 kgVSS/kgCOD,仅为SBR0.57 kgVSS/kgCOD的8.8%。此外,研究发现SBBR在停止运行后经3个运行周期可回复原油能力,而SBR池经9个周期培养也不能恢复,说明SBBR恢复能力明显优于SBR。 研究表明,以匀质调节—SBBR—BAF为主的制革废水处理工艺,出水水质稳定,进水COD 801~2,834 mg/L、NH4+-N 87~203 mg/L,出水COD<80 mg/L、NH4+-N<10 mg/L,基本达到中水回用标准;操作简单灵活,没有污泥回流系统,污泥产率低,污泥处理费用低;工艺基本不需要添加化学药剂,既节约成本、又避免了二次污染;两级生物膜使得该工艺具有很强的耐冲击负荷能力,特别适合制革废水水质水量波动大的特点。 研究表明,高效菌对系统的启动具有一定的促进作用,强化系统生物膜6天可以成熟,对照系统生物膜9天可以成熟。同时高效菌能加速COD降解,缩短停留时间,强化系统6~8 h可使COD<200 mg/L,对照系统8~10 h可使COD<200 mg/L。长期运行表明,强化系统的SBBR在COD和NH4+-N的去除率都优于对照系统的SBBR。最终出水COD强化系统平均为53 mg/L、对照系统为74 mg/L。在模拟循环过程中,强化系统均有更高的稳定性。可实现8次理论循环,而对照系统只能实现4次理论循环。 研究表明,通过合理的工艺设计,可以实现猪皮制革废水达到《污水综合排放标准GB8976-1996》一级标准,同时满足工厂部分用水要求。通过添加高效微生物,可提高生物处理系统处理能力,使处理水能够满足工厂的多次回用。 As a labour-intensive industry, tanning has created large amount of working opportunities as well as caused severe contamination to environment. And it is one of the highest water-consuming and polluting industry, only second to manufacturing. At present time, Chinese leather industry emits wastewater about 80,000,000~120,000,000 t annually, which contains chromium about 3,500 t, SS 1.2×105 t, COD 1.8×105 t, BOD 7×104 t and ambient riverhead has been polluted greatly. Based on the research of anaerobic acidification and comparison of SBBR and SBR, biotreatment process (Homogenization—SBBR—BAF) had been established to amend the disadvantages of traditional sewage treatment such as too much sludge, high cost of advanced treatment and NH4+-N can not reach the emission standard. Research on the bioaugmentation was also been carried out. Researches showed, when COD of influent was beyond 3,000 mg/L, anaerobic acidification could resist strong impact, thus COD of effluent was less than 200 mg/L; when COD of influent was less than 3,000 mg/L, only throughout aerobic sewage treatment could COD of effluent beless than 200 mg/L. False residence tiome of anaerobic acidification would lead to the higher effluent concentration of sulfide and disintegration of aerobic activated sludge. Researches showed SBBR worked a better than SBR: when influent between 2,000 and 2,500 mg/L, NH4+-N between 130 mg/L and 146 mg/L, COD, NH4+-N removal rate of SBBR was 93.3%~96.6%, 14.5%~55.9% respectively while COD, NH4+-N removal rate of SBR was 88.8%~94.9%, 13%~50.7% respectively. Sludge growth rate of SBBR was 8.8% of that of 0.05 kgVSS/kgCOD. Besides, SBBR could recovered after 3 operating periods while SBR worked no better after 9 operating periods.Therefore, SBBR excelled SBR. Researches showed, effluent quantity of tannery wastewater treatment process (Homogenization—SBBR—BAF) was stable. When COD of influent was between 801 and 2,834 mg/L, NH4+-N was between 87 mg/L and 203 mg/L, COD of effluent was less than 80 mg/L, NH4+-N was less than 10 mg/L, which achieved the standard of reuse. This biotreatment was featured in low cost, easy and flexible management, less sludge, no inverse sludge system. Besides, this technique required no chemical, which could lower the cost and avoid secondary pollution. Great resistant of impact due to two membranes and was suitable for tannery wastewater which was featured by fluctuation of influent quality and quantity. Researches showed effective microorganisms promotes the startup of the process.Biofilm in the bioaugmentation process matured with 6 days while biofilm in normal process matured with 9 days. Effective microorganisms could accelerate the degradation of COD and shorten the residence time. Aggrandizement system could make COD<200 mg/L with 6 to8 hours while cntrolling system could make COD<200 mg/L with 8 to 10 hours. Long-term operating shows that SBBR in the bioaugmentation system worked better than the normal system in the treatment of COD and NH4+-N. The average COC of effluent in bioaugmentation system was 53 mg/L, normal system was 74 mg/L. In the simulative circulation process,aggrandizement process, which could fulfill 8 times theoretical circulation, works more stably than controlling process which could only fulfill 4 times theoretical circulation. Researches showed that reasonable design could make the wastewater meet the first grade of discharging standard of National Integrated Wastewater Discharge Standard (GB8976-1996), and partially meet the demand of water using of the factory. Adding effective microorganisms could enhance the biotreatment and make the effluents reuse many times.

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A marine green alga, Platymonas subcordiformis, was demonstrated to photobiologically evolve hydrogen (H-2) after the first stage of photosynthesis, when subjected to a two-phase incubation protocol in a second stage of H2 production: anaerobic incubation in the dark followed by the exposure to light illumination. The anaerobic incubation induced hydrogenase activity to catalyse H? evolution in the following phase of light illumination. H,) evolution strongly depended upon the duration of anaerobic incubation, deprivation of sulphur (S) from the medium and the medium pH. An optimal anaerobic incubation period of 32 h gave the maximum H2 evolution in the second phase in the absence of sulphur. Evolution of H,) was greatly enhanced by 13 times when S was deprived from the medium. This result suggests that S plays a critical role in the mediation of H-2 evolution from R subcordiformis. A 14-fold increase in H-2 production was obtained when the medium pH increased from 5 to 8; with a sharp decline at pH above eight. H-2 evolution was enhanced by 30-50% when supplementing the optimal concentrations of 25 mM acetate and 37.5 mM glucose. (C) 2003 Elsevier B.V. All rights reserved.

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Desorption/ionization on silicon mass spectrometry (DIOS-MS) is a matrix-free technique that allows for the direct desorption/ionization of low-molecular-weight compounds with little or no fragmentation of analytes. This technique has a relatively high tolerance for contaminants commonly found in biological samples. DIOS-MS has been applied to determine the activity of immobilized enzymes on the porous silicon surface. Enzyme activities were also monitored with the addition of a competitive inhibitor in the substrate solution. It is demonstrated that this method can be applied to the screening of enzyme inhibitors. Furthermore, a method for peptide mapping analysis by in situ digestion of proteins on the porous silicon surface modified by trypsin, combined with matrix-assisted laser desorption/ionization-time of flight-MS has been developed.

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Germination of non-dormant upper cocklebur (Xanthium pinsylvanicum Wallr.) seeds was stimulated by not only CS(NH2)2 but also NH2OH, KCN and NaN3. This stimulation was not via the enhancement of aerobic C2H4 production. NH2OH, KCN and NaN3 in certain concentrations promoted the initial growth of axial and/or cotyledonary parts, but the degree of growth promotion by NH2OH, NaN3 and KCN was slight compared with that by CS(NH2)2. As in the case of CS(NH2)2, however, the germinationstimulating effect of NH2OH disappeared rapidly as the preceding imbibition period was prolonged. In contrast, KCN and NaN3 were still effective in stimulating the germination of aged seeds maintained on a water substratum, as previously seen with anaerobiosis. Anaerobic induction was enhanced not only by NaN3 and KCN but also by NH2OH, KNO3, KNO2 CO(NH2)2 and CS(NH2)2 applied during the anaerobic treatment, but without causing an increase in anaerobic production of C2H4. Furthermore, KCN and NaN3, given prior to the anaerobic treatment acted additively with anaerobic induction. The germination-stimulating actions of nitrogenous compounds are discussed in comparison with those of C2H4 and anaerobiosis.

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The validation of a fully automated dissolved Ni monitor for in situ estuarine studies is presented, based on adsorptive cathodic stripping voltammetry (AdCSV). Dissolved Ni concentrations were determined following on-line filtration and UV digestion, and addition of an AdCSV ligand (dimethyl glyoxime) and pH buffer (N-2-hydroxyethylpiperazine-N′-2-ethanesulphonic acid). The technique is capable of up to six fully quantified Ni measurements per hour. The automated in situ methodology was applied successfully during two surveys on the Tamar estuary (south west Britain). The strongly varying sample matrix encountered in the estuarine system did not present analytical interferences, and each sample was quantified using internal standard additions. Up to 37 Ni measurements were performed during each survey, which involved 13 h of continuous sampling and analysis. The high resolution data from the winter and summer tidal cycle studies allowed a thorough interpretation of the biogeochemical processes in the studied estuarine system.