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In this paper, bioconversion of trans-cinnamic acid(t-Ca)to L-phenylalanine (L-phe) has been investigated by using immobilized yeast cells with induced L-phe Ammonia-lyase(PAL, EC.4.3.1.5) as biocatalysts. The contents are the following. (1) Thirty strains of yeasts, including two genera (Rhodotorula, Sporobolomyces), six species (R. glutinis R. minuta,R.rubra,R.sineses,R.roseus and S.salmonicolor)were screened for their ability to converse the substrates, t-Ca and ammonia, to the product, L-phe, by using yeast cells as biocatalyst, and primary evaluation for PAL activity of the selected strains was investigated. From the results of the screening experiments, it was found that 22 strains were able to produce L-phe from t-Ca with the range of conversion yield from 2% to 67%. Studies on PAL formation time course during cultivation show that the maximum PAL activity of several different strains ranges from 2.3 to 14.4×10-3U/mg cell dry weight. The biomass of tested strains at their maximum enzyme activity is also greatly varied. (2)One of the selected strains, R. rubra as 2.166, was used for immobilized cells as biocatalysts to produce L-phe. The optimum conversion conditions and effective stablization agents were investigated. The results shown that polyacrylamide gel was chosen as a suitable matrix for immobilization of the yeast cells, and it can retain 88% of the PAL activity in the reverse direction at the following reactive conditions: [t-Ca]: 34mM. [NH4OH]: 6.OM.PH10.00, temperature: 30℃. (3) The effects of various kinds of effectors on the production of L-phe were also examined. Membrane permeabilizing agents can stimulate L-phe synthesis, but make the stability of PAL decline greatly. Polyalchoholic agents and glutamic acid were very effective for the stabilization of PAL. At the presence of glutamic acid (5%), the half life of L-phe productivity with the immobilized cells was extended to 192 hours, which was much higher than most of that having been reproted, while the half life of resting cells was only about 15 hours. (4) Use of initial velocity studies on the kinetics of enzyme-catalized reaction indicated that the apparent Km value was 13.0mM for the immobilized cells, and 4.8mM for the resting cells. Thermostability of the immobilized cells was better than the resting cells. Fluid bed bioreactor is more effective than batch bioreator in prolonging the thermostability of the biocatalysts. (5) CGA- 688 resin column chromatographic procedure was employed in the isolation and purification of L-phe, t-Ca and other substances from the reactire mixture. (6) Preparative-scale production of L-phe on a level of gram amount by immobilized cells from the culture broth of R. rubra AS2.166 allowed for the conversion yield with 30%. The characteristic physico-chemical criteria (including melting point, optical activity, elements analysis, IR, NMR) are the same with the standard L-phe. 本文报告了利用诱导的苯丙氨酸解氨酶 (PAL.EC.4.3.1.5)催化反式肉桂酸(t-Ca)氨加 成制备L-苯丙氨酸(L-phe)的研究,主要内容为:(1) 我们搜集了三十株酵母菌株,利用全细胞转化t-Ca生成L-phe的能力进行了直 接筛选,并对其PAL活性水平进行了初步评估研究。研究结果表明,其中22株酵母具有转化t-Ca生产L-phe的能力,它们包括 Rhodotorula glutinis,R.rubra, R.sineses 和Sporobolomyces roseus 的菌株,转化率在2-67%。细胞生长和PAL形成过程的研究 表明,不同菌株PAL最大活力在2.3-14.4×10-3U/mg 细胞干重,达到最大PAL活性时各株酵母的生长情况也极不一致。(2) 利用筛 选出的一株深红酵母R.rubra AS2.166 作为供试菌株,研究了细胞固定化条件下生物转化的最适条件及PAL在固定化条件下的稳定 性。结果表明以聚丙烯酰胺凝胶包埋法较为理想,能使细胞合成L-phe活力保持88%,最适t-Ca浓度为34mM,最适NH4OH浓度为6M,最 适PH10.0,最适温度45℃。(3) 多种效应物对L-phe 合成的影响研究表明:表面活性剂能刺激L-phe的合成,但使PAL稳定性下降。 多羟基化合物及Glu对PAL的稳定十分有效在有Glu存在下,能使固定化细胞合成L-phe的半寿期达192小时左右,高于大部分现已报 导的固定化结果。(4) 用初速度法研究了深红酵母AS2.166中PAL的酶促反应特征,测得固定化细胞对t-Ca的表观米氏常数Km为 13.0mM,全细胞为4.8mM,细胞固定后热稳定性提高。(5) 建立了适合低浓度分离纯化产物与底物的聚苯乙烯大孔树脂柱层析技术 ,能使L-phe与t-Ca及产物混合物中其它成分有效分开。(6) 利用固定化的R.rubra AS2.166细胞所做的制备实验能够使L-phe的产 率达到30%左右,其主要的理化指标(包括熔点、比旋光度、元素分析、IR、NMR等)与标准L-phe一致。

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我们从成都东郊垃圾堆里分离到一株产生水不溶性葡聚糖降解酶的菌株CIB871,经鉴定为假单孢菌。CIB871在30℃生长良好。适宜的产酶培养条件是在含有一定金属离子的盐溶液中加入氮源多胨(终浓度0.3%)和碳源IG(终浓度0.03%)或甘露醇(终浓度1%)。上清液酶浓度在培养60-65小时达到最高。利用饱和度50%-70%的硫酸铵沉淀该酶。酶作用的最佳PH为7.0,最佳温度37℃,热稳定性不良。5mM的Ag+,Co2+,Hg2+, Mg2+, Zn2+ 对酶有抑制作用。Fe2+,Fe3+对酶有激活作用。

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从四川化工总厂热交换器中分离到一株嗜热硫酸盐还原菌,该菌对金属有腐蚀作用。菌体形状呈微弯或直杆状,大小为0.5-0.8μm宽,2.8-4.3μm长,革兰氏阴性,周生鞭毛,运动,形成次端生的椭圆形芽孢,细胞内部构造丰富,菌落在不含Fe++盐的培养基上生长时,呈灰白色,直径为0.5mm,边缘不整齐,在含Fe++盐的培养基上生长时则为黑色,直径为2-3mm,菌落中央有0.5mm左右的小突起,该菌最适生长温度为50℃,最适PH6.5,不耐盐,可于沸水(99℃)中处理6小时而不失活,能利用H2+CO2,乙醇,卜葡糖 ,可溶性淀粉,甲酸盐,乳酸盐,丙酮酸盐为唯一碳源,生长需要酵母膏,无脱硫弧菌素和细胞色素C3。

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为结合一般白酒存在的杂醇油含量偏高或超标问题,作者试图寻找能嗜高醇类(含杂醇油)的有效菌株加以开发利用。本文研究了一株从富集分离、定向诱导得到的嗜异戊醇的W-2菌,该菌能以异戊醇或其它某些多碳醇作为唯一的碳源和能源进行生长。该菌在PH8.5的环境条件下,异戊醇的利用率可高达84.4%。此外,该菌还能广泛利用糖类、醇、有机酸、酯、盐等有机物作为唯一的碳源和能源。一般不利用—碳化合物。该菌具单极生鞭毛,呈杆状,适宜生长温度范围4℃—43℃。最适生长温度36℃,在PH4.0—11.0均能生长,最适生长PH为8.5—9.0,在培养基产生蓝绿色色素。W-2菌经形态,生理生化鉴定为假单胞菌属中的铜绿假单胞菌的一个变种。初步定名为Pseudomonas aeruginosa W-2。本文最后讨论了该菌的开发应用前景。

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从成都市洪河垃圾场采样分离到三株嗜热纤维素分解细菌,均为严格厌氧的革兰氏阴性杆菌,有较高的纤维素降解活性,能直接转化为纤维素产酒精。其中TCl菌株为周生鞭毛运动,不产生芽孢,大小为0.9×2.4~5.4um,表明菌落为白色,边缘整齐的圆形,最适温度在55℃,最适PH大约7.0,发酵纤维素或纤维而糖产生乙酸、丁酸。该菌属于拟杆菌料(Bacteroidaceae),不能归入已有的任何一属,很可能是一个新的属。TC3和TC4为单端丛生鞭毛运动,大小为0.6×2.4~15um,形成卵圆形或圆形的端生芽孢,使菌体膨大。TC3的菌落为灰白色、透镜状,TC4的菌落为黄色,透镜状,TC4在液体培养基中产生非水溶性黄色素。最适温度均为55℃,最适PH值TC3为8.0,TC4为7.5。TC3、TC4属于梭菌属,与所有已报道的同类菌株均有显著差异,因此认为它们可能是梭菌属 (clostridium)中的新种。

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本文报告了丝状真菌单宁酶发酵五倍子及有机溶剂中酶法合成没食子酸丙酯的研究。利用单宁和/或五倍子诱导丝状真菌产生单宁 酶的原理,借助二级发酵程序,对从天然源得到的75株菌进行了生物转化实验研究。选择出既能水解单宁或五倍子成没食子酸,又 能把没食子酸和丙醇合成没食子酸丙酯,而且生物催化活性都较高的1株菌,这株菌经初步鉴定为黑曲霉(Aspergillus niger No.17)。随后对它开展了产酶条件和参数优化实验,得出了最佳培养条件。立足于参数优化实验方案的基础上,经由液体培养发酵 制备单宁酶制剂,并把该酶通过化学手段共价结合到一种新型载体—聚乙烯醇和戊二醛反应生成的缩醛上,制备得到固定化单宁酶 。这种固定化生物催化剂在两种有机介质体系中都具有逆向催化合成没食子酸丙酯的能力。最后建立起来一条有效可行的微生物酶 法制备没食子酸的技术途径,没食子酸产率达到70%。对这种物质进行元素 分析:含C,49.45%;含H,3.63%。它的熔点为237℃~243 ℃,三种溶剂系统的TLC均只给出一个斑点。这些数据都与标准品一致。有机溶剂中酶法合成没食子酸丙酯的技术途径已经建立。 水溶性单宁酶在潜溶剂体系中也能催化上述酯化反应,反应混合物中的PG浓度为16.4mmol/L,制备薄层被用于分离反应混合物所含 的PG,这种产物被红外、质谱及三种溶剂系统的TLC等方法鉴定,确证为目标产物。在这一学位论文的实验研究过程中,还包括一 些生化分析方法的建立和应用,这些方法用于鉴定底物和产物及测定它们的浓度,其内容主要包括TLC定性/半定量分析、元素分析 、质谱、红外等手段的综合运用。本工作为开发我国特有的天然产物资源—五倍子的生物化工加工技术及非水相生物催化技术的开 发,提供了有用的基础数据资料,具有应用基础研究工作的重要性。In this thesis, the studies on the fermentation of Chinese gallotannin by filamentous fungi with tannase activity and enzymatic synthesis of propyl gallate(PG) in organic solvents were described through these biocatalysts. Based on the principles of induction enzyme, the tannase produced from filamentous fungi by adding tannic acid(TA) and/or Chinese gallotannin into media was investigated, and the screening experiments of bioconversion were done with 75 strains by means of a two-stage fermentation procedure. These strains were isolated with the enrichment culture technique from natural sources. Hence we selected one strain (Aspergillus niger No.17) that can not only catalyze the hydrolyses of TA and/or Chinese gallotannin into gallic acid(GA) in the liquid cultures, but also be used to synthesize PG from propanol and GA in the non-aqueous media. At the same time both of its biocatalytical activities were higher. This strain was calssified to be Aspergillus niger by the primary identification. Then optimum conditions for production of the tannase and its parameters were examined. In this way, one set of optimum culture conditions was selected. Making use of the optimum proposal, the tanase was prepared through a liquid fermentation procedure. The enzyme was convalently coupled to a new type of carrier which was made chemically from polyvinyl alcohol(PVA)and glutaraldehyde. The immobilized enzymes were able to synthesize PG reversely in two organic media. Finally, an effective enzymatic technique for production of GA was developed. The yield of GA products was up to 70%。Element analysis for this substance: calce: C, 49.42%; H, 3.56%; found: C, 49.45%, H, 3.63%. Its melting point was 237℃~ 243℃ and TLCs on three solvent systems gave only one spot respectively. These data were identical with theauthentic GA. The enzymatic synthesis of PG in organic solvents was extablished with reverse route of tannase catalytical hydrolysis. Aqueous enzyme perparation also catalyzed above esterification in a buffer system. The PG concentration in the reaction mixture was 16.4mmol/L. The reparative-scale TLC was used to isolate PG from the reaction mixture. This product separated was identified by IR, MS and TLC on three solvent systems. In this study of thesis, some biochemical analytical mehtods were developed and used to identify substrates and products, and to determinate their concentration. These methods, including TLC qualitative/half quantitative analysis, element analysis, MS, IR and so on, were useful, available and performable. This work provided basic data and information for developing the biochemical engineering and bio-processing of Chinese gallotannin-a special natural resource in China and the non-aqueous phase biocatalysis. Thus, this study possesses importance in the applied and basic research work.

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本文研究了两种微生物及其组合沥取、回收用微生物法治理电镀铬废水产生的铬污泥中的铬。铬污泥富含C、N、O,含铬量为13%, 经X-光电子能谱分析铬以三价态(氢氧化铬)存在。二种微生物分别从一酸性矿水和酸性污泥中分离筛选得到,经鉴定为硫杆菌属 (Thiobacillus Beijerinek)的两个不同种,一为氧化亚铁硫杆菌(Thiobacillu ferrooxidans, TF), 另一为氧化硫硫杆菌 (Thiobacillus thiooxidans, TT)。研究并比较了不同微生物对污泥中铬的沥取能力,结果表明,TT菌沥取铬效率最高。振荡、动 态淋滤、静置等沥取方式经过研究表明动态淋滤为最佳,室温条件下(15-20℃),污泥浓度为20g/L时,总铬沥出率达60%时所需时 间:动态淋滤为48.5h,振荡和静置方式分别为91.22,81.6h。研究了不同温度、不同起始PH、不同污泥浓度及非成熟菌液对微生 物沥取能力的影响:(1) 沥取前期,温度对铬的沥出影响较大;微生物沥取反应基本属一级反应;温度与反应速率的关系基本符合 Arrhenius方程,但沥取后期这一特点并不突出。(2) 沥取液最适起始PH为菌液自然PH;PH值的人为改变将使铬的沥出大大降低。 (3) 污泥浓度与铬的沥出呈正相关,但浓度高于30g/L时,铬的沥出量不再增加。(4) 非成熟菌液沥出铬的能力较差,但沥取液中 微生物生长繁殖较为活跃。总结微生物沥取反应最佳沥取条件为:TT成熟菌液、污泥浓度10g/L、温度25-36℃、动态淋滤方式,此 时铬几乎可100%从污泥中沥出。经扫描电镜分析,沥取开始时,微生物紧密吸附于污泥颗粒表面上,表面紧密吸附为微生物发挥功 能提供了基础。微生物沥取污泥中铬的反应机理推测为:硫细菌代谢产硫酸或氧化Fe2+成Fe3+,利用酸,Fe3+ 及自身氧化酶系统 氧化污泥中Cr3+为Cr6+,Cr6+溶出结晶为CrO3。This paper has studied bioleaching and recovery of Chronium(Cr)from electroplating sludge by two consortum of bacteria and their combination, with sludge produced by microbiological process treating electroplating wastewater containing Cr as material. The share of Cr is 13% and its state is Cr (OH)3 in the sludge. One of the bacteria in the paper was isolated from acid sewage sludge and the other was from acid mineral water. The former was tested and determined as Thiobacillus ferroxidans(TF) and the latter was Thiobacillus thiooxidans(TT). Different microorganisms, responsible for the metal leaching activity, have great influence on the efficiency of leaching. The results showed that TT has biggest power. Experiments were conducted to examined effects of three different ways of leaching(Shaking, Down-leaching, Static-leaching). When temperature was in-door's (15-20℃)and concentration of the sludge was 20g/L, the bioleaching time required to reach 60% of Cr solubilization with the above three ways were 91.2, 48.5, 81.6h respectively. Down-leaching was proved to be the most efficient. The influence of different temperature, initial PH, concentration of the sludge and non-mature inoculum had been studied. The results obtained reveal that: (1) The variation of temperature is important during the time from initial to middle of leaching. The reaction of bioleaching belongs to first-order. The relation between the bioleaching rate constant(In k)and temerature can be expressed by Arrhenius function. (2) The fittest initial PH is the nature PH of mature inoculum. Any alteration with it could cause clearly negative effection. (3) The concentration of the sludge can make strong influence on the bioleaching efficiency. But when the concentration is above 30g/L, the increasing of Cr in the solution is little. (4) If non-mature inoculum acts as the bioleachin microorganism, little quantity of Cr would be gained from the sludge. But the micormass in the solution is very active. The results from electron microscope showed that microorganisms adhered to the surface of the sludge and the adherence was the first stage of the bioleaching. Some salts of Cr can be obtained afer the water of the bioleaching solution being evaporated. By analysing the results of experiment with X-Ray spectroscopy, the salt was identified as CrO3. The recovery rate of Cr is 78.4%.

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单宁是一种典型的有毒难降解污染物,在制革、造纸、制药、印染等行业废水中广泛存在,对水环境造成污染并且影响废水生物处理效果。本研究针对含单宁废水生物处理效率低、较高浓度时微生物受抑制且污泥容易膨胀等问题,采用超声和磁粉来强化含单宁废水生物处理,研究超声和磁粉对微生物活性、污染物去除及污泥沉降性能的影响,并对其作用机理进行了分析和探讨。 研究结果表明,活性污泥系统中单宁酸容积负荷可以达到1.8kgCOD/(m3·d),单宁酸和COD去除率分别达到85.2%和79.6%,但如果负荷进一步增大则微生物活性迅速降低。系统在pH 5~8、温度20~35℃、DO>1 mg/L的条件下具有较好的单宁酸降解效果和处理稳定性。单宁降解动力学参数为:μmax =0.208h-1;Ks=226mg/L;Ki=522mg/L;kd=0.0092h-1;Y =0.594。 磁粉对系统处理效果和污泥沉降性能有一定的促进作用,且效果要优于外磁场。适宜的磁粉粒径和投加量分别为0.05~0.15mm和1.0g/L,COD去除率比对照系统提高6.4%,SVI降低28.6%,污泥絮体结构紧密。磁粉强化主要是通过其对污泥菌胶团的凝聚、吸附作用以及对微生物活性的强化作用实现。 在适当强度(0.4W/cm2)和辐照时间(20min)的超声作用下污泥絮体和细胞膜通透性增大,酶分泌也增多,系统的COD去除率比对照提高了8.8%,单宁酶酶活提高了11%。但超声也使污泥絮体结构松散,沉降性能下降,SVI比对照系统升高9.3%。 由于污泥流失加剧导致污泥浓度相对较低,声磁联合强化系统相对于磁粉强化系统其处理效果并没有提高。但相对于单纯活性污泥系统,声磁联合作用下系统处理效果、污泥沉降性能以及系统运行稳定性都得到明显改善。本研究为难降解废水的生物处理提供了一个新的思路。 Tannins are typical refractory and toxic pollutants that commonly exist in wastewater from dye, medicine, paper and leather industries and cause many problems associated with environmental pollution and biological treatment of wastewater. Biological treatment efficiency of tannin-containing wastewater is usually low owing to its biological toxicity and low biodegradability, microbes are usually inhibited under high tannin concentration and sludge bulking frequently occurs. In this study, ultrasound and magnetic powder were used to improve the biological treatment performance of simulated tannic acid-containing wastewater. The effects of ultrasonic irradiation and magnetic powder on microbial activity, tannic acid degradation rate and sludge sedimentation were investigated. The augmentation mechanisms were analyzed and discussed. The experimental results showed that the microbes were prominently inhibited under high tannic acid concentration, but moderate degradation efficiency can be maintained under a tannic acid load of up to 1.8kgCOD/(m3·d), with the tannic acid degradation and COD removal percentage of 85.2% and 79.6% respectively. The highest degradation rates and treatment stability were achieved at pH range of 5~8, temperature range of 20~35℃ and DO concentration of above 1mg/L. The kinetic parameters were estimated, including: μmax =0.208h-1;Ks=226mg/L;Ki=522mg/L;kd=0.0092h-1;Y =0.594. The microbial activity, tannic acid degradation rate and sludge sedimentation were improved by adding Fe3O4 magnetic powder, and the augmentation performance was better than external magnetic field. The appropriate particle size and dosage of magnetic powder were found to be 0.05~0.15mm and 1.0g/L, respectively, under which the COD removal percentage was improved by 6.4% and SVI value decreased by 28.6%, and compact floc structure was observed. This was mainly caused by the flocculation and adsorption effects of magnetic powder against sludge floc and the stimulation of microbial activity under appropriate magnetic field. Under appropriate ultrasonic irradiation (ultrasonic intensity 0.4W/cm2, ultrasonic irradiation time 20min), the permeability of floc and cell membrane are improved, transfer of substrate and oxygen were reinforced; meanwhile, more enzyme were produced by microbes under the slight damage caused by ultrasound. However, the floc structure became loose under ultrasonic irradiation, leading to relatively poor sedimentation, with the SVI value 9.3% higher than the control system. Although the magnetic powder-ultrasonic irradiation combined augmentation system showed no improvement in treatment performance compared with sole magnetic augmentation system owing to its relatively low sludge concentration, it guaranteed the stable operation of system, meanwhile the tannic acid degradation and sludge sedimentation were significantly improved compared with sole activated sludge system. This study gives a new idea for biological treatment of refractory wastewater.

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畜禽废水是农村水环境污染的主要来源之一,其处理的难点在于脱氮。传统生物脱氮法具有能耗高、需大量外加碳源等缺点,开发低成本、高效率的新型生物脱氮技术具有重要意义。 本研究将短程硝化反硝化和厌氧氨氧化两种脱氮新技术结合,让前者为后者创造去除可降解COD、降低总氮负荷、调整pH、调整氨氮和亚硝酸盐氮浓度比例等进水条件,而后者可在无需外加碳源的条件下进一步脱氮,二者结合可成为高氨氮、低C/N废水脱氮的新途径。 试验以低碳氮比猪场废水为研究对象,首先进行了短程硝化反硝化预处理研究,同时启动并运行调控厌氧氨氧化反应器,最后以经过短程硝化反硝化预处理的猪场废水为进水,进行厌氧氨氧化脱氮考察。实验表明:(1)短程硝化反硝化作为厌氧氨氧化的预处理工序是可行的。猪场废水通过短程硝化反硝化,可以达到基本去除可生化COD、部分脱氮、控制出水氨氮和亚硝酸盐氮浓度之比在1︰1左右、pH在7.5~8.0的目的, COD和总氮平均去除率分别为64.3%、49.1%,出水可达到厌氧氨氧化反应的进水要求。(2)采用模拟废水启动厌氧氨氧化反应器,经过5个月左右的运行调控,反应器启动成功并稳定运行,最高总氮去除率为87.1%,总氮容积去除率最高达到0.14kg/m3.d;整个稳定阶段,氨氮、亚硝酸盐氮、硝酸盐氮的变化量之比为1︰1.21︰0.33。(3)经过短程硝化反硝化预处理的猪场废水厌氧氨氧化脱氮效果稳定,氨氮、亚硝酸盐氮、总氮、COD的平均去除率分别为93.0%、99.4%、84.6%、18.1%,处理效果与模拟废水处理系统相比无明显变化。(4)经过短程硝化反硝化预处理后,猪场废水中残留有机物成分在厌氧氨氧化反应过程中无显著变化,主要为酯类和烷烃类物质;残留有机物对厌氧氨氧化效果无明显影响。(5)采用PCR技术进行特殊功能菌种检测,结果表明模拟废水处理系统和猪场废水处理系统的菌群中均含有厌氧氨氧化菌和好氧硝化菌;通过blast比对,厌氧氨氧化菌扩增序列与未培养的Planctomycetales菌和Candidatus Brocadia fulgida菌16S rRNA部分序列相似性分别为95%、90%。(6)MPN法菌种计数结果显示,模拟废水处理系统和猪场废水处理系统的菌群中均含有硝化细菌、亚硝化细菌和少量反硝化菌,实验条件下的微生物系统是一个厌氧氨氧化菌与好氧硝化菌、反硝化菌共存的系统。 Poultry wastewater is one of the main source of water pollution in rural areas,and nitrogen removal is the most difficult part in treating poultry wastewater. There are some disadvantages in traditional nitrogen removal, such as high energy consumption and more additional organic carbon. It is important to develop ecolomical and efficient technologyies. Shortcut nitricfication/denitrification, as a pretreatment process, was combined with Anammox in this research, so that part of total nitrogen and most degradable COD could be removed by the former, and further nitrogen removal could be implemented by the latter. The combination of the two technologies was a new approach to treat wastewater with high ammonium and low C/N. Piggery wastewater with low C/N was treated in lab-scale experiment. Firstly, shortcut nitrification/denitrification was investigated, and Anammox reactor was started up successfully at the same time. Then piggery wastewater after pretreatment was treated by Anammox. The results showed :(1) It was feasible to take nitrification/denitrification as the pretreatment process of Anammox. By using this process, part of total nitrogen and COD were removed, the ratio of ammonium and nitrite reached around 1︰1 and the pH was about 7.8, which were favorable for Anammox. The average removal percentage of COD and total nitrogen were about 64.3% and 49.1%, respectively. (2) Simulated wastewater was used to start up Anammox reactor. The reactor was started up successfully within 5 months and stable performance was achieved. The highest nitrogen removal reached 87.1% and the biggest volumetric total nitrogen removal rate reached 0.14kg/m3.d. The average ratio of ammonium, nitrite and nitrate was 1:1.21:0.33. (3)Taking the effluent of shortcut nitrification/denitrification as the influent, the nitrogen removal efficiency of Anammox was stable, and the the average removal percentage of ammonium, nitrite, total nitrogen and COD were 93.0%, 99.4% , 84.6% and 18.1%, respectively, which had little difference with that by using simulated wastewater..(4) After pretreatment, the residual organic carbon in piggery wastewater showed no obvious change during the Anammox process, and the main organic compounds were saturated hydrocarbon and ester, which had no obvious negative effect on Anammox process.(5) By PCR technology, the existence of Anammox bacteria was confirmed and the aerobic nitrifying bacteria was found to coexist as well. The result of blast showed that the identities of Anammox bacterium to part of 16S rRNA sequence of uncultured Planctomycetales bacterium and Candidatus Brocadia fulgida bacterium were 95% and 90%, respectively.(6)By MPN method, nitrite oxidizer, ammonium oxidizer and denitrification bacteria were detected in both simulated and piggery wastewater treatment system of Anammox, and the microorganism system was composed of Anammox bacteria,aerobic bacteria and denitrification bacteria together.

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近年来,我国炼油行业发展迅速,炼油能力全世界第二,炼油行业已成为污染大户。本研究针对炼油废水生物处理中存在的稳定达标难、抗冲击负荷能力差、建设投资与运行成本高等问题,就菌剂强化处理炼油废水中试与工程应用展开了研究,以期为菌剂的工程应用与推广提供理论参考与技术支持;并以炼油废水中的主要特征污染物苯酚为研究对象,考察了不同浓度苯酚冲击下功能菌的响应机制,并以此为指导研制功能菌激活促进剂,考察其对功能菌生物学指标的调控效果,以期为废水生物处理有毒污染物冲击调控提供理论依据与技术支持。 中试研究表明,菌剂强化处理炼油废水,出水COD、NH4+-N 平均值为86.7、7.6 mg/L,其平均去除率较常规生物处理系统分别提高了35.47%、59.28%,其耐受COD、NH4+-N 容积负荷分别高达2.42、0.139kg/(m3·d),具有良好的耐冲击能力。工程应用研究表明,菌剂强化处理炼油废水,出水COD、NH4+-N 平均值分别为85.05、8.4mg/L,其去除率较常规生物处理系统提高了25.1%、28.7%,出水水质各项指标均达到了国家《污水综合排放标准GB 8978-1996》一级排放标准。技术经济分析表明,菌剂强化处理炼油废水在建设成本、运行成本上分别降低38%、49%,具有良好的技术经济优势。 苯酚冲击下功能菌响应机制研究表明:不同浓度苯酚冲击下,生物学指标生物量、脱氢酶酶活、1,2-双加氧酶酶活对冲击都有不同程度的响应,其响应敏感程度为脱氢酶酶活>生物量>1,2-双加氧酶酶活。1,2-双加氧酶酶活与COD 降解率相关性良好,可表征苯酚降解过程,确认为调控重点。以此为指导研制出苯酚降解功能菌抗冲击激活促进剂,可有效调控功能菌对有毒污染物苯酚的降解效果,1000mg/L 苯酚冲击下,经调控,其COD 去除率较对照提高20%,降解时间缩短16%以上。其对生物学指标的调控效果为1,2-双加氧酶酶活>生物量>脱氢酶酶活,验证了功能菌在苯酚冲击下的响应机制。研究表明菌剂强化处理炼油废水切实可行,具有良好的技术经济优势。有毒污染物冲击下废水生物处理系统响应机制研究为抗冲击调控提供了新的研究思路。 Currently, China’s oil refining industry is developing rapidly and has become the second largest all over the world. The oil refining industry is one of the major pollution industries in our country. The pilot scale study and engineering application research were conducted aiming at the problems in refining wastewater such as poor treatment stability and water quality, poor anti-shock capacity and expensive running cost, etc., so as to provide theoretical references and technological supports for the engineering application and popularization of microbial preparation in wastewater treatment. Also, the response mechanism of functional microbe under shock of different phenol concentrations, which is the main pollutants in refinery wastewater, was studied. Based on this result, functional microbe activation accelerator was developed, and the regulation effect of functional microbe biological index under phenol shocking were studied, in order to provide theoretical basis and technological support for regulation of toxic shocking of wastewater biological treatment. The result of pilot scale research indicated: for treatment of refinery wastewater in bioaugmention treatment system of microbial preparation, the COD and NH4+-N average value of effluent was 86.7 and 7.6 mg/L, Comparing with normal biological treatment system, the average removal rates of COD, NH4+-N increased 35.47%,59.28% separately by bioaugmention treatment system, which showed better anti-shocking capacity, the volumetric load r of COD and NH4+-N reached 2.42 kg/(m3·d) and 0.139 kg/(m3·d), respectively. The research on engineering application of refinery wastewater bioaugmentation treatment by microbial preparation indicated:the average concentrations of effluent COD and NH4+-N in the bioaugmentation treatment system were 85.05 and 8.4mg/L, which increased by 25.1% and 28.7% comparing with normal biological treatment system of refinery wastewater, And the effluent quality meets the first grade of discharging standard of National Integrated Wastewater Discharge Standard GB 8978-1996. The economic analysis of technology indicated: the demonstration project of bioaugmentation treatment of refinery wastewater by microbial preparation decreased by 38% in construction cost and 49% in running cost. This technology has economic benefits. The response mechanism of functional microbe under phenol shock indicated: biological index such as the biomass concentration, dehydrogenase and 1,2-dioxygenase had different responses under phenol shocking of different concentrations. The response sensitivity of different biological index under phenol shocking of different concentrations is: dehydogenase activity > biomass >1,2-dioxygenase activity, and high correlation of 1,2-dioxygenase and COD degradation percentage is achieved, thus 1,2-dioxygenase could be used to reflect the degradation situation of pollutants. So, 1,2-dioxygenase is the keypoint of regulation. The anti-shock activation accelerator of phenol degradation functional microbe was primarily developed. The results indicated: the activation accelerator could regulate the degradation effect of toxic substance-phenol by functional microbe effectively. For the functional microbe treatment system under phenol shocking of 1000mg/L, the COD degradation rate increased by 20% and the degradation time reduced by more than 16% under regulation of activation accelerator. The regulation effects of biological index are: 1,2-dioxygenase > biomass > dehydrogenase. In this way, the response mechanism of functional microbe under toxic shocking is verified. The result indicated: the augmented microbial preparation treatment of refinery wastewater is applicable. It has many technical and economical advantages. The research results of responses mechanism of wastewater treatment system on toxic pollutants would offer a new idea for regulation of anti-shock.

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随着化工行业的发展,大量有毒有害难降解有机物随工业废水的排放进入环境,这些物质能够在环境中长期存在、积累和扩散,通过食物链对动植物的生存及人类的健康造成不良影响。本文以苯酚、对氯硝基苯、氯苯和十六烷为模拟污染物,以前期研制的功能菌剂为对象,经过紫外线线诱变筛选出优于出发菌株的功能菌,对诱变后功能菌的理化性能进行了研究,对菌种进行了鉴定,在此基础上,就其相互之间的微生态关系进行研究,为混合发酵提供理论基础,并就其最佳发酵条件及发酵参数进行了研究,最后对发酵产品的性能进行了检测。目前,国内外有关功能菌剂的研究还存在多方面的不足,主要包括:①由于多菌种混合发酵过程较为复杂,各菌之间存在复杂的相互作用,影响因素较多,关于菌种之间的相互关系研究得很少,环境功能菌剂的发酵方法大多采用单独发酵后混合的方式。单独发酵对原材料、设备和能源的利用率较低,对于多菌种制剂发酵,在设备、能源和原材料的方面造成的浪费更大,将会大幅增加菌剂的生产成本,影响多菌种功能菌剂的发展;②功能菌剂生产过程的质量控制方面研究得较少;③功能菌剂产品的稳定性、抗冲击性能研究得较少,对环境微生物制剂的研究主要集中在菌种选育和培养条件优化方面。 通过本论文研究,得到以下主要结论。 (1)在紫外线诱变处理中,用紫外线对发生一定程度退化的出发菌株进行诱变处理后,六株具有高效降解性能的菌株被筛选出来,诱变筛选出的菌株形态和ERIC-PCR指纹图谱与出发菌株相比发生了明显改变;而且诱变后的菌株对目标难降解底物的降解能力均得到改善,其中,FPN、FCB、F14、FEm对目标底物的降解率提高了20%以上;诱变后菌株经过7次连续传代接种后,对目标难降解底物的降解率无显著变化,具有一定的遗传稳定性。并对诱变后的功能菌进行了初步的鉴定,这6株菌都分别是芽孢杆菌。 (2)对诱变后的功能菌相互之间的微生态关系进行了研究,通过抑菌实验、生长量以及基质消耗量的比较,确定它们之间的生长关系是无害共栖关系,可以进行混合发酵。 (3)对该功能菌剂进行发酵培养条件研究,结果表明发酵培养基的最佳成分(g/L):葡萄糖 31.0g/L、玉米粉10.0g/L、磷酸氢二钾1.0g/L、硫酸铵1.1g/L、硫酸镁0.55g/L。通过研究不同的培养条件对菌体生长和降解性能的影响,确定了最佳培养条件:培养基初始pH7.5;最适温度32℃;培养基装液量125mL(250 mL三角瓶),以及培养时间对降解性能的影响,培养20 h的产物对降解最为有利。通过研究添加不同目标污染物对菌体生长和降解性能的影响,确定了添加目标污染物的最佳量以及最佳时间:苯酚投加量:1.125 g/L,对氯硝基苯投加量:0.1 g/L;最佳投加时间为发酵培养开始后4 h。 (4)以摇瓶分批发酵最优条件为基础,对FPN、F10、FCB、FNa、F14 和 FEm进行了摇瓶分批发酵试验。以摇瓶分批发酵试验数据为依据,对功能菌剂分批发酵动力学进行了研究,建立了菌体生长和基质消耗的动力学模型,拟合模型能较好的反映功能菌剂分批发酵过程。 (5)功能菌剂和活性污泥协同作用,可以提高系统的生物降解能力,功能菌剂投加量为2%,新鲜活性污泥3500 mg/L,降解24 h条件下,功能菌剂和活性污泥的协同作用对COD的去除率和对照组相比,最多的提高了36.8%。功能菌剂和活性污泥协同作用以及活性污泥的单独作用,其生物降解过程均符合一级反应动力学过程,功能菌剂和活性污泥协同作用的生物降解动力学方程为:,相关系数97%。采用SBR运行方式,引入功能菌剂的SBR系统明显能够改善和提高生物降解的效率。与仅有活性污泥的系统相比,系统对COD的平均去除率可以提高27.1%,同时,系统的耐负荷冲击以及耐毒害冲击的性能比仅有活性污泥的SBR系统强,特别是负荷冲击对引入功能菌剂的SBR系统影响很小。仅有活性污泥的SBR系统经过负荷冲击和毒害冲击之后,不能恢复到冲击之前的水平,而且系统有效作用时间的周期比引入功能菌剂的SBR系统相比大大缩短,而引入功能菌剂的SBR系统处理效果较为稳定,恢复能力很强。 Along with the development of industries, many recalcitrant organic chemicals have been discharged into natural environments together with wastewaters and can exist in waters, soil and sediments for a long time without degradation. These haz-ardous substances, their byporducts and metabolizabilities can be highly toxic, mu-tagenic and carcinogenic, thereby threatening animals, plants and human health through food chain. Consequently the removal of these compounds is of significant interest in the area of wastewater treatment. In this dissertation, the phenol, hydro-quinone, chlorobenzene and hexadecane treated as the model pollutants, the func-tional microorganism agent was used as the starting strains, they treated with ultra-violet light, and then the mutant strains with high degradation ability were screened out and identified primarily, the relationship between these stains were studied, the medium composition and fermentation conditions were optimized, the degradation ability of the fermented production was tested. The literature survey indicates that the study of the microorganism agent is far from complete and more information is re-quired on following problems. 1, Because of the complexity of relationship in mixed fermentation and the complicated factors, the study is hardly to process.2, There is a lack of information on the quality control of the producing process .3, And there is a lack of information on the stability about the microorganism agent. In this dissertation, the main results of the present study could be summarized as follows: (1)The degenerate starting strains were treated with the ultraviolet light, and six mutant strains with high biodegradation ability were screened out by using the me-dium with selective pressure of model pollutants. The mutant strains had great changes in colonialmorphology and ERIC-PCR fingerprinting. And the mutant strains got obvious advantages over the starting strains in degradation ability and over 20% improvement of removal rates was achieved for FPN、FCB、F14 and FEm. The de-gradation ability of the mutant strains was stable after seven generations. After that, the mutant strains were primarily identified as bacillus respectively. (2) The relationship between these mutant strains was studied. By the compari-son of antibiosis effect, biomass and consumption of substrate, the relationships were neutralism and they could be mixed fermented. (3) The optimized cultivation conditions were as follows: glucose 31.0 g/L, corn power 10 g/L, K2HPO4 1.0 g/L, (NH4)2SO4 1.1 g/L, MgSO4 0.55 g/L, initial pH7.5, temperature 32℃, working volume 125 mL/250 mL, and cultivation time 20h (con-sidering the time effect on degradation ability), adding pollutants phenol (1.125 g/L) and hydroquinone (0.1 g/L) into the broth at 4 h after cultivation. (4) Based on the above optimum condition, the batch fermentation was per-formed with strains FPN, F10, FCB, FNa, F14 and FEm in shake flask. The batch fermentation kinetics was studied based on the experimental data. Two kinetic models were constructed which could reflect the regularity of growth and substrate consump-tion in the process of batch fermentation. (5) The co-operation of functional microorganism agent and activated sludge could raise biodegradation of system by adding some microorganism agent and 3500 mg/L fresh activated sludge. Bioaugumentation by the addition of high effective deg-radation culture enhanced the treatment effect of SBR system and the COD removal rate was increased by 20%-36.8%. Its biodegradation matched first-order dynamical reaction equation, and the reaction equation was ln0.2327.391ct=−+. The micro-organism agent had the effect of optimization to activated sludge micro-ecosystem. The SBR system adding 2% microorganism agent, the average COD removal rate of that was increased by 27.1% and stronger anti-shock ability to load and toxicant were achieved (compared with SBR system just adding activated sludge). Especially the load-shock has barely effect to the SBR system adding microorganism agent. After the load and toxicant shock, the SBR system just adding activated sludge couldn’t come back to original level and the activated sludge micro-ecosystem was frustrated. The applying of microorganism agent increased biological activity and system’s re-sistance ability to load shock and toxicant shock.

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以克拉维酸产生菌棒状链霉菌Streptomyces clavuligerus CCRC11518(ATCC 27064)III50为出发菌株, 首先比较各种物理和化学诱变剂处理对其克拉维酸生物合成的影响, 确定了亚硝基胍为棒状链霉菌诱变育种的诱变剂及其处理剂量: 2mg/ml、40min. 经浓度为2mg/ml的亚硝基胍处理40min后, 采用新颖理性化筛选方法, 通过逐步筛选自身代谢产物抗性突变株、克拉维酸抗性突变株和链霉素抗性突变株, 最终得到一株克拉维酸高产菌VI118(效价633μg/ml), 其克拉维酸效价是出发菌株(效价377μg/ml)的167.9%. 该高产突变株在琼脂斜面培养基上连续传接10代, 克拉维酸效价保持稳定. 通过单因子和多因子摇瓶正交试验, 对高产菌株VI118的发酵条件进行了研究, 确定最佳发酵条件: 甘油60g, 水解植物蛋白 60g, KH2PO4 0.5 g, 玉米浆 7.5g, MnSO4•H2O 0.34g, MgSO4•7H2O 0.99g, FeSO4•7H2O 0.56g, 蒸馏1000ml, pH 7.0, 发酵培养基装量20ml/250ml三角瓶, 接种量10%, 培养温度28ºC, 220r/min摇床培养72h后测定效价. 在最佳发酵条件下克拉维酸效价达到651μg/ml, 同时把初始发酵培养基的昂贵成分替换为廉价的工业原料. 通过摇瓶分批补料试验, 得到最佳补料物质和补料方式:在上述最佳发酵条件下, 分别在发酵培养48h、56h、64h、72h时补加4ml无菌水, 80h发酵结束, 克拉维酸效价达到905μg/ml. 在不增加原料成本的情况下通过摇瓶补料方式克拉维酸效价为未补料的139.0%, 总产量为未补料的264%. By a novel rational screening method, mutant Streptomyces clavuligerus CCRC11518(ATCC 27064)III50(titres 377μg/ml), as the clavulanic acid-producing parent strain, was treated by NTG (2mg/ml) for 40min, and the self-generated metabolites resistant mark, the clavulanic acid resistant mark and the streptomycin resistant mark were added step by step. Finally, the mutant VI118(titres 633μg/ml)with the three marks was obtained. The clavulanic acid productivity of this mutant was increased by 167.9% compared with the parent strain. After reproducing 10 generations on the agar medium slant, the productivity of this mutant was stable. The optimum fermentation conditions were established as followings: glycerol 60g, acid hydrolyzed vegetable protein 60g, KH2PO4 0.5g, corn steep liquor 7.5g, MnSO4•H2O 0.34g, MgSO4•7H2O 0.99g, FeSO4•7H2O 0.56g, distilled water 1 liter, pH 7.0, 20ml in 250ml shake-flask, inoculation 10%(v/v), fermentation temperature 28ºC, rotation speed 220 r/min, time 72h. The clavulanic acid productivity was 651μg/ml, while used the low-priced industrial raw materials. After studying on fed-batch in the shake-flask, the optimum fed-batch manner was obtained: under optimum fermentation conditions, at 48h, 56h, 64h and 72h, adding 4ml distilled water into each flask, fermentation ending at 80h. The clavulanic acid productivity was increased by 139% compared with no fed-batch, meanwhile the total yield was increased by 264%.

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红发夫酵母分离于北美西部高山地区和日本一些岛屿上落叶树的渗出液中,因其所产主要色素为在水产养殖、食品和医药工业有广阔应用前景的虾青素而成为研究的热点。本论文对红发夫酵母Phaffia rhodozyma 的生长特性、培养参数与培养基组分对生长和虾青素积累的影响及其优化、虾青素合成的调节控制、虾青素的提取测定及红发夫酵母耐高温菌种的诱变进行了系统的研究。 虾青素是红发夫酵母的胞内色素,要对其进行分析首先要对红发夫酵母进行破壁处理,实验发现二甲亚砜是最有效的破壁溶剂,用氯仿和丙酮可以有效地把类胡萝卜素从二甲亚砜破壁后的红发夫酵母细胞中提取出来。 在固定摇床转速为200 rpm,温度为20 ℃的条件下,当种龄为36 h,以10%的接种量接入装液量为30 mL的250 mL三角瓶,初始pH为5.5时最有利于红发夫酵母的生长及类胡萝卜素的合成。 本实验中红发夫酵母最佳利用碳、氮源分别为蔗糖和蛋白胨,但蛋白胨价格昂贵,不适宜作单一氮源,因此使用硫酸铵和酵母膏作为复合氮源。 本论文采用了BP神经网络结合遗传算法的方法来优化红发夫酵母的发酵培养基,得到红发夫酵母发酵培养基的最佳配比为:蔗糖45.10 g/L、硫酸铵3.00 g/L、硫酸镁0.80 g/L、磷酸二氢钾1.40 g/L、酵母膏3.00 g/L、氯化钙0.50 g/L,使用优化后的培养基发酵类胡萝卜素产量达到8.20 mg/L,干重达到9.47 g/L,类胡萝卜素的产量比起始培养基提高了95.90%,干重提高了89.40%。 从代谢途径出发对红发夫酵母合成虾青素调控调控,选择谷氨酸、乙醇、VB1作为添加剂,通过正交试验设计得出三者添加水平分别为0.2 g/L,0.1% (V/V),10 mg/L时,类胡萝卜素产量提高了25.73%,达到了10.31mg/L。 通过上述优化培养,本论文中红发夫酵母的虾青素产量从1.33 mg/L提高到9.12 mg/L,产量提高了6.86倍;总类胡萝卜素产量从4.23 mg/L提高到10.31 mg/L,产量提高了2.44倍;细胞干重从5.00 g/L提高到11.35 g/L,提高了2.27倍,总体提高效果显著。 红发夫酵母属于中低温菌,本论文采用紫外复合诱变的方式,通过高温筛选,得到一株能在35 ℃下能生长的突变株,但所产类胡萝卜素中虾青素所占比例很小,可能是诱变改变了红发夫酵母的代谢途径,阻断了虾青素的合成。 Phaffia rhodozyma is a heterobasidiomyceteous yeast that was originally isolated from the slime fluxes of brich tree wounds in mountain regions of northern Japan and southern Alaska. Phaffia rhodozyma produces astaxanthin as its principal carotenoid pigment, which has potential applications in acquaculture, food and pharmaceutical industry. This paper researched ways to break cell, analysis of astaxanthin, characteristics of growth, culture parameters and the effects of components of medium on growth and astaxanthin formation , optimization of culture medium, control of astaxanthin synthesis and mutagenesis of Phaffia rhodozyma. It is necessary to disrupt the yeast cell for extracting astaxanthin considering the yeast accumulating carotenoids in cell. Dimethyisulphoxide was the most effective solvent for breaking the yeast cell; acetone and chloroform were effective to extract carotenoids out of the disrupted cell. The optimum pH for growth and carotenoids synthesis is 5.5, the optimum medium volume is 30 mL (in 250 mL flask), the optimum culture time of inoculum is 36 h, the optimum inoculum concentration is 10%. The research on culture medium showed: sucrose is the best one of 6 carbon sources for growth and astaxanthin synthesis. Peptone is the best nitrogen source for growth and astaxanthin synthesis. Uniform Design was used for trial design of the formula medium components, then back-propagation neural network was established to modeling the relationships between the carotenoid yield and the concentration of medium components. Genetic algorithm (GA) was used for global optimization of the model. The optimum combination of the medium was obtained: sucrose 45.10 g/L, ammonium sulfate 3.00 g/L, magnesium sulfate 0.80 g/L, potassium dihydrogen phosphate 1.40 g/L, yeast extract 3.00 g/L, calcium chloride 0.50 g/L. The yield of carotenoid reached 8.20 mg/L, which was 95.90% higher than that of the original medium. Glu, VB1 and ethanol were selected as fermentation addictives, after Orthogonal Test, the carotenoid contents increased by 25.73% when adding 0.16 g/L Glu, VB1 10 mg/L and ethanol 0.1% (V/V). After the above optimization, the astaxanthin content increased 6.86 folds, which is 9.12 mg/L. The carotenoids content increased 2.44 folds, which is 10.31 mg/L. The biomass increased 2.27 folds, which is 11.35 g/L. Phaffia rhodozyma grows in the mild temperature range of 0 to 27 ℃, in this work, a thermotolerant mutant was selected through UV-irradiation. It can grows at 35 ℃, and showed increased carotenoid content. The optimal growth temperature for this mutant is 30 ℃. But the mutant can only produce carotenoids with little astaxanthin accumulation.

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本文结合我国燃料乙醇发展的方针政策,以酿酒酵母和运动发酵单胞菌为菌种研究其在非粮能源作物木薯中乙醇发酵的情况,为木薯原料更好地应用于生产中提供了理论依据。 酿酒酵母木薯高浓度乙醇发酵的研究。实验采用的木薯干淀粉含量约70-75%。以酿酒酵母为菌种进行高浓度乙醇发酵的工艺条件研究,最佳条件为:木薯干粉碎细度为35目,料水比1:2,α-淀粉酶用量0.09 KNU/g淀粉,蒸煮温度85 ℃,蒸煮时间15 min。采用30 ℃同步糖化发酵工艺,糖化酶用量为3.4 AGU/g淀粉,发酵时间30 h。在10 L发酵罐中,乙醇质量比达127.88 g/kg,发酵效率为88.28%,发酵强度4.263 g/kg/h,100 L中试研究中乙醇浓度为127.75 g/kg,发酵强度4.258 g/kg/h。利用高效液相色谱对发酵液中残糖进行了分析,证明葡萄糖、果糖等单糖已完全被菌体利用,剩余糖为二糖,三糖等不可发酵的低聚糖。 运动发酵单胞菌快速乙醇发酵的研究。对实验室保藏的8株运动发酵单胞菌进行比较,选择发酵速度最快的Zymomonas mobilis232B进行研究。该菌在纯葡萄糖中的最佳发酵条件为:葡萄糖浓度18%,起始pH 6-7,发酵温度30 ℃,发酵时间18 h,乙醇浓度88 g/kg。在以木薯为底物同步糖化快速乙醇发酵中,采用Full Factorial设计和最速上升实验确定了培养基成分中的2个显著性因子及其最适浓度:酵母粉4 g/kg,硫酸铵0.8 g/kg。在最适培养基条件下,对木薯料水比和糖化酶用量进行了优化,得到Z.mobilis232B木薯乙醇发酵最佳料水比1:3,糖化酶浓度4 AGU/g淀粉,乙醇发酵4.915 g/kg/h。利用高效液相色谱对发酵液中残糖进行了分析,剩余糖为二糖,三糖等,但成分较酵母发酵后复杂。 According to the fuel ethanol development plans and policies in our country, the ethanol production from cassava by Saccharomyces cerevisiae and Zymomonas mobilis was studied. It provided theoretical basis for ethanol fermentation by cassava in industry. Part 1 is the study of VHG (very high gravity) ethanol fermentation by Saccharomyces cerevisiae. The content of starch in cassava was 70-75%. Compared with the performances under different experimental conditions, the following optimal conditions for VHG fermentation were obtained: Granule size of dry cassava 35 mashes, hydromodulus of cassava to water at 1:2, α-amylase enzyme dosage 0.09 KNU/g starch, cooking temperature 85 ℃ for 15 min, using the SSF process (simultaneous saccharification and fermentation) and the amount of glucoamylase 3.4 AGU/g starch. Accordingly, the final ethanol concentration was up to 127.88 g/kg; the ethanol yield reached 88.28%, and ethanol productivity was 4.263 g/kg/h after 30 h. When the fermentation scale expanded to 100 L, the final ethanol concentration was 127.75 g/kg, and the ethanol productivity was 4.258 g/kg/h in 30 h. The residual sugar was analyzed by high performance liquid chromatography, and proved that there was no glucose and fructose. The residual reducing sugar was some unfermentable oligosaccharide Part 2 is the study of the rapid ethanol production by Zymomonas mobilis. Compare with other seven stains, Zymomonas mobilis 232B was selected for research. The optimum condition in glucose medium was as follow: glucose concentration 18%, initial pH 6-7, and fermentation temperature 30 ℃. The ethanol concentration was 88g/kg in 18 h. After that, rapid ethanol production from cassava in SSF by Zymomonas mobilis 232B was studied. Through a series of experiments aided by Full Factorial Design and steepest ascent search, the optimal concentration yeast extract and ammonium sulfate were determined: 4 g/kg and 0.8 g/kg, each. Under optimum medium conditions, the optimal hydromodulus of cassava to water and glucoamylase dosages were obtained: hydromodulus of cassava to water at 1:3 and glucoamylase dosages 4 AGU/g starch. The ethanol production reached 4.915 g/kg/h. The residual sugar was analyzed by HPLC, and proved that the residual reducing sugar was some unfermentable oligosaccharide,but the components were more complex than that fermentation by Saccharomyces cerevisiae.