971 resultados para Ferrous sulfate


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Continuous gradient elution chromatography (CGEC) was employed to purify and separate enzymes and polysaccharides from the sap of Rhus vernicifera Chinese lacquer tree. There are three different molecules with laccase enzyme activity. Two are enzymes of each other (L1, and L2), whereas the third (RL) is an entirely separate entity. Two polysaccharides (GP1 and GP2) were also found. The Rhus laccase (RL), and isoenzymes L1 and L2, have peak molecular masses of 109,100, 120,000, 103,000 respectively; each has four copper atoms per molecule, and the pI values were 8.2, 8.6, and 9.1, respectively. The structure of the laccases was studied by Fourier-transform infrared (FT-IR) and Matrix-assisted laser desorption/ionization time-of flight (MALDI-TOF) mass spectrometry. The typical amide I (1646 cm(-1)) and amide II (1545 cm(-1)) bands were observed. The results from MALDI-TOF were similar to those from CGEC, but the molecular mass from the MALDI-TOF was significantly different from that obtained from sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). (c) 2006 Elsevier B.V. All rights reserved.

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Thin aluminum oxide films were deposited by a new and simple physicochemical method called chemical liquid phase deposition (CLD) on semiconductor materials. Aluminum sulfate with crystallized water and sodium bicarbonate were used as precursors for film growth, and the control of the system's pH value played an important role in this experiment. The growth rate is 12 nm/h with the deposition at [Al-2(SO4)(3)]=0.0837 mol.L-1, [NaHCO3]=0.214 mol.L-1, 15 degreesC. Post-growth annealing not only densifies and purifies the films, but results in film crystallization as well. Excellent quality of Al2O3 films in this work is supported by electron dispersion spectroscopy, Fourier transform infrared spectrum, X-ray diffraction spectrum and scanning electron microscopy photograph.

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实验研究了添加剂对甲烷气体水合物形成过程的影响。发现微量的表面活性剂降低了甲烷气体水合物在静止反应器中形成的诱导时间,并使水合物快速形成和生长,提高了水合物形成过程中的填充密度。阴离子表面活性剂(十二烷基硫酸钠)对水合物生长的促进作用比非离子表面活性剂(烷基多糖苷)强。液态烃环戊烷降低了水合物形成的诱导时间,但环戊烷不能提高水合物的填充密度。


The effect of additives on methane gas hydrate formation was tested. The induction time of methane hydrate formation was reduced, gas hydrate could grow rapidly, and the methane consumption was improved during hydrate formation in a quiescent cell with micella surfactants. The effect of an anionic surfactant ( sodium dodecyl sulfate) on gas hydrate formation is more pronounced compared to a nonionic surfactant (dodecyl polysaccharide glycoside). Cyclopentane reduced the induction time of hydrate formation, but could not improve the methane consumption during gas hydrate formation in a quiescent cell.

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The porous medium has an important effect on hydrate formation. In this paper, the formation process and the gas storage capacity of the methane hydrate were investigated with A-type zeolite and Sodium Dodecyl Sulfate (SDS) existing in the system. The results show that A-type zeolite can influence methane hydrate formation. At the temperature of 273.5 K and pressure of 8.3 MPa, the distilled water with A-type zeolite can form methane hydrate with gaseous methane in 12 hours. The formation process of the system with A-type zeolite was quite steady and the amount of A-type zeolite can influence the gas storage capacity significantly. The adding of A-type zeolite with 0.067 g.(g water)(-1) into 2 x 10(-3) g.g(-1) SDS-water solution can increase the gas storage capacity, and the maximum increase rate was 31%. Simultaneously the promotion effect on hydrate formation of 3A-type zeolite is much more obvious than that of 5A-type zeolite when the water adding amounts are 0.033 g.g(-1) and 0.067 g.g(-1) at the experimental conditions.

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Here we reported the fatty-acids and their δ 13C values in seep carbonates collected from Green Canyon lease block 185 (GC 185; Sample GC-F) at upper continental slope (water depth: ∼540 m), and Alaminos Canyon lease block 645 (GC 645; Sample AC-E) at lower continental slope (water depth: ∼2200 m) of the Gulf of Mexico. More than thirty kinds of fatty acids were detected in both samples. These fatty acids are maximized at C16. There is a clear even-over-odd carbon number predominance in carbon number range. The fatty acids are mainly composed of n-fatty acids, iso-/anteiso-fatty acids and terminally branched odd-numbered fatty acids (iso/anteiso). The low δ 13C values (−39.99‰ to.32.36‰) of n-C12:0, n-C13:0, i-C14:0and n-C14:0 suggest that they may relate to the chemosynthetic communities at seep sites. The unsaturated fatty acids n-C18:2 and C18:1Δ9 have the same δ 13C values, they may originate from theBeggiatoa/Thioploca. Unlike other fatty acids, the terminally branched fatty acids (iso/anteiso) show lowerδ 13C values (as low as −63.95‰) suggesting a possible relationship to sulfate reducing bacteria, which is common during anaerobic oxidation of methane at seep sites.

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The feasibility of biodiesel production from soapstock containing high water content and fatty matters by a solid acid catalyst was investigated. Soapstock was converted to high-acid acid oil (HAAO) by the hydrolysis by KOH and the acidulation by sulfuric acid. The acid value of soapstock-HAAO increased to 199.1 mg KOH/g but a large amount of potassium sulfate was produced. To resolve the formation of potassium sulfate, acid oil was extracted from soapstock and was converted to HAAO by using sodium dodecyl benzene sulfonate (SDBS). The maximum acid value of acid oil-HAAO was 194.2 mg KOH/g when the mass ratio of acid oil, sulfuric acid, and water was 10:4:10 at 2% of SDBS. In the esterification of HAAO using Amberylst-15, fatty acid methyl ester (FAME) concentration was 91.7 and 81.3% for soapstock and acid oil, respectively. After the distillation, FAME concentration became 98.1% and 96.7% for soapstock and acid oil. The distillation process decreased the total glycerin and the acid value of FAME produced a little.

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Density gradient ultracentrifugation (DGU) has emerged as a promising tool to prepare chirality enriched nanotube samples. Here, we assess the performance of different surfactants for DGU. Bile salts (e.g., sodium cholate (SC), sodium deoxycholate (SDC), and sodium taurodeoxycholate (TDC)) are more effective in individualizing Single Wall Carbon Nanotubes (SWNTs) compared to linear chain surfactants (e.g., sodium dodecylbenzene sulfonate (SDBS) and sodium dodecylsulfate (SDS)) and better suited for DGU. Using SC, a narrower diameter distribution (0.69-0.81 nm) is achieved through a single DGU step on CoMoCAT tubes, when compared to SDC and TDC (0.69-0.89 nm). No selectivity is obtained using SDBS. due to its ineffectiveness in debundling. We assign the reduce selectivity of dihydroxy bile salts (S DC and TDC) in comparison with trihydroxy SC to the formation of secondary micelles. This is determined by the number and position of hydroxyl ( OH) groups on the a-side of the steroid backbone. We also enrich CoMoCAT SWNT in the 0.84-0.92 nm range using the Pluronic F98 triblock copolymer. Mixtures of bile salts (SC) and linear chain surfactants (SOS) are used to enrich metallic and semiconducting laser-ablation grown SWNTs. We demonstrate enrichment of a single chirality, (6,5), combining diameter and metallic versus semiconductillg separation on CoMoCAT samples.

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砷是毒性最强的元素之一,水体中砷的污染己经引起人们广泛的关注。我国的新疆、内蒙、山西和台湾等省和地区地下水砷含量严重超标。全球共有5,000多万人遭受高砷饮用水的威胁,其中中国有1,500多万,是饮用水砷污染最严重的国家之一。WHO推荐饮用水砷的最高允许浓度从原来的50 µg•L-1已降至10 µg•L-1。更为严格的砷卫生标准的颁布,对作为饮用水源的地下水中的砷去除工艺提出了更高的要求。吸附法除砷比膜法、混凝法和离子交换法更安全、简便,是砷去除工艺中最有效的方法之一。 首先,本研究通过优化制备条件(包括炭种类的选择、炭的粒径大小、还原剂的浓度及滴定速率、反应温度、铁盐的种类及浓度、分散剂的比例及浓度),制备了负载型纳米铁。考虑到砷的去除效率、工程应用的可行性以及经济性,最优的制备条件如下:选用粒径为20~40目煤质炭,在室温、一定的分散剂比例及浓度,0.2 M KBH4滴速为20 d•min-1时所制备的Fe/炭为82.0 mg•g-1;纳米铁在活性炭孔内呈针状,其直径为30~500 nm,长度为1,000~2,000 nm。绝大多数的铁都负载到活性炭内部,这在处理水时铁不流失很重要。 其次,利用制备的负载型纳米铁作吸附载体,进行了饮用水中As(Ⅴ)的吸附去除实验。研究了该吸附剂对As(Ⅴ)的吸附等温线、动力学以及影响动力学的各种因素(包括As(Ⅴ)的不同初始浓度、吸附剂用量、pH值、共存离子和不同温度)、pH值、共存离子等环境条件对As(Ⅴ)去除的影响;以及吸附剂的再生及再生后的吸附效率等。研究发现在前12 h内吸附较快,72 h时达到了平衡。用Langmuir 吸附等温式估算出As(Ⅴ)的吸附量为12.0 mg•g-1。该吸附剂在pH 6.5, (25±2)℃, As(Ⅴ)初始浓度为2 mg•L-1,吸附剂用量为1.0 g•L-1时,As(Ⅴ)的去除率为75.2%;当把吸附剂的用量增加到1.5 g•L-1时,As(Ⅴ)的去除率可达99.9%以上。吸附剂可以用0.1M的NaOH浸泡12 h后即可再生,再生效率较高。常见的阴离子中PO43-、SiO32-对As(Ⅲ)的去除抑制较大,而SO42-、CO32-、C2O42-等离子对砷的去除影响较小。Fe2+对As(Ⅲ)的吸附抑制作用较大而其它阳离子影响不大。吸附剂可用0.1 M NaOH 有效再生,并且具有良好的机械性能。实验室初步实验数据表明,该吸附剂对饮用水除砷具有较好的应用前景。 第三,利用实验室制备的负载型纳米铁对饮用水中As(Ⅲ)的吸附去除也进行了研究。考察了吸附等温线、动力学以及影响动力学的各种因素、pH值、共存离子等环境条件对As(Ⅲ)去除的影响;以及吸附剂的再生及再生后的吸附效率等。研究发现,该吸附剂在pH 6.5, (25±2)℃, As(Ⅲ)初始浓度为2 mg•L-1,吸附剂用量为1.0 g•L-1时, 对As(Ⅲ)的去除率为99.8%;其吸附容量为1.996mg•g-1。吸附过程中部分As(Ⅲ)被氧化。与As(Ⅴ)的吸附相比,该吸附剂对As(Ⅲ)的效率比较高-而常见的其它除砷吸附剂如载铁纤维棉等,对As(Ⅴ)的效率比As(Ⅲ)高,为有效去除As(Ⅲ),常常需要专门加上氧化这一过程。 最后,利用负载型纳米铁对饮用水中As(Ⅲ) 的氧化性能进行考察,发现该吸附剂不但能够有效吸附去除饮用水中的砷,而且还能把As(Ⅲ)有效地氧化为As(Ⅴ)。经过对吸附剂的构成组分分析发现,活性炭表面因富含多种官能团而对三价砷的氧化作用最大;其次是纳米铁也能把As(Ⅲ)氧化为As(Ⅴ)。

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对15株白腐真菌进行了以玉米秸秆为基质的初步筛选,从中获得一株选择性系数较高的菌株Y10,并对其降解玉米秸秆的情况进行了研究。结果表明,在30天的培养过程中菌株Y10对玉米秸秆降解的选择性系数都大于1,第15天选择性系数最高为3.88。对未经降解和降解过的玉米秸秆分别作了紫外光谱和红外光谱分析,结果表明,经该菌降解后玉米秸秆的化学成分发生了很大变化,且木质素的降解程度要大于纤维素的降解程度。对菌株Y10进行了ITS-5.8S rDNA序列鉴定,初步判定其为Cerrena sp.。 为了考查不同的外源添加物对菌株Y10降解玉米秸秆的影响,在以玉米秸秆为基质的固态发酵培养基中分别添加了7种金属离子、8种碳源、6种氮源。结果显示,这7种金属离子均能促进木质素的降解,并且一定浓度的某些离子明显抑制纤维素的降解;其中添加0.036%的MnSO4·H2O和0.36%的MgSO4·7H2O对纤维素降解的抑制作用比较强,降解率分别为0.96%和1.31%,木质素的选择性系数分别达到了34.40和20.17。8种碳源中除麦芽糖外都能促进木质素的降解,除微晶纤维素外都明显促进纤维素的降解。6种氮源中酒石酸铵、硫酸铵、草酸铵和氯化铵的添加都会使该菌生长变慢,而且氮源浓度越高菌丝生长越慢。外加碳源和金属离子对半纤维素降解和选择性系数的影响不大。 同时对菌株Y10在液态培养下产木质素降解酶的条件和培养基做了优化。结果表明,在初始产酶培养基中,菌株Y10的漆酶酶活在第10d达到最高,锰过氧化物酶酶活在第11d达到最高,基本上检测不到木质素过氧化物酶。菌株Y10产漆酶的最适温度为32℃,最适PH为6.0;产锰过氧化物酶的最适温度为32℃,最适PH为6.5。菌株Y10产漆酶的最佳碳源为甘露糖,最佳氮源为酒石酸铵,最适诱导剂VA浓度为3 mmol/L,最适表面活性剂TW-80浓度为1%。 利用响应面法对其产漆酶的培养基进行优化,优化后的培养基配方为葡萄糖10.00 g/L,酒石酸铵0.50 g/L,大量元素296.50 ml/L,微量元素100.00 ml/L,NTA 1.40 g/L,VA 5.00 mmol/L,吐温-80加入量为0.10%。进行了菌株Y10产漆酶的验证实验,实测酶活为5282.56 U/L,与预测酶活5162.73 U/L接近。在优化后培养基中,菌株Y10在第14 d达到生长的最高峰,第20 d时,漆酶酶活最高,为11325.00 U/L;第16 d时,锰过氧化物酶酶活最高,为30.77 U/L。 对菌株Y10的漆酶酶学性质做了初步的研究,结果显示,酶反应的最适温度为40℃-65℃,最适PH为3.0。在40℃,PH=3.0时,漆酶催化ABTS反应的米氏方程为 。 Fifteen white-rot fungi based on corn stalk were screened. One white-rot fungus Y10 with high selectivity value was obtained. The degradation of corn stalk was initially studied. The results indicated that the selectivity value was above 1 during the 30 day-cultivation and the highest was 3.88 after 15 days. The composition of untreated and treated stalk was analyzed through ultraviolet spectroscopy and infrared spectroscopy. It was found that the composition of treated stalk was greatly altered and the degree of the degradation of lignin is greater than the cellulose. Y10 was identified as Cerrena sp. by ITS -5.8S rDNA sequence analysis. The influence of metal ions, carbon sources and nitrogen sources on corn stalk degradation by white-rot fungus was studied. While all seven metal ions could promote lignin degradation, the cellulose degradation was best inhibited at certain ion concentrations. Notably, when 0.036% MnSO4·H2O and 0.36% MgSO4·7H2O were added into the medium, the cellulose degradation was restrained to the extents that the coefficients of lignin selectivity rose to 34.40 and 20.17 respectively. It was also found that all carbon sources except maltose can promote lignin degradation. The addition of carbon sources other than microcrystalline cellulose significantly promoted cellulose degradation. The addition of the nitrogen sources, ammonium tartrate, ammonium sulfate, oxalate, ammonium chloride, resulted in remarkable inhibition to mycelium growth; the larger the concentrations of nitrogen sources are, the slower the mycelium grew. The addition of carbon sources and metal ions had less impact on the degradation of hemicellulose and selectivity value. Meanwhile, we optimized the conditions and culture medium of the lignin-degrading enzyme production of strain Y10. The results showed that in the initial culture medium, the Lac activity was highest at the 10th day, the MnP activity was highest at the 11th day and the LiP could not be detected. The optimum condition of Lac was at temperature 32 and PH =6.0 and the optimum condition of MnP was at temperature 32 and PH =6.5. The optimum carbon source for Lac was seminose, the optimum nitrogen source was ammonium tartrate, the optimum content of VA was 3 mmol/L, the optimum content of TW-80 was 1%. PB and RSM were used to optimize the culture medium of laccase by white-rot fungus Y10. The optimum culture medium was consist of glucose 10.00 g/L, ammonium tartrate 0.50 g/L, macro elements 296.50 ml/L, trace elements 100.00 ml/L, NTA 1.40 g/L, VA 5.00 mmol/L, TW-80 0.10%. Under the optimal conditions, the activity of laccase was 5282.56 U/L and the experimental value agreed with the predicted value 5162.73 U/L. The biomass was highest at the 14th day, the Lac activity was highest at the 20th day, the MnP activity was highest at the 16th day. The results of the studies on the characteristics of Lac showed that the optimum temperature for Lac activity is 40℃-65℃ ; the optimum PH for Lac activity is 3.0 and under 40℃,PH=3.0, the Michaelis-menten equation of Lac catalized ABTS oxidation was .

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造纸行业是造成我国水环境有机污染物的重要污染源之一,其水污染的特点是小厂多、草浆多、工艺落后、污染扩散面广、造成废 水排放量大,每年排放的废水量约39亿立方米,占全国工业废水排放量的1/6,其中有机污染物(以BOD5计)160万吨左右,约占全 国工业废水中有机污染物总量的1/4。尤以占全国制浆造纸行业90%以上的碱法草浆造纸厂的蒸煮黑液量大面广,除含有机物外,还 含有木质素、残碱、硫化物、氯化物等污染物,属于PH值高、色度深、难于治理的高浓度有机废水,对水体污染特别严重,各地要 求治理呼声很高,急待研究并尽快找出各种有效的治理途径。对于碱法草浆蒸煮,黑液高浓度废水的治理,有各种方法,根据国内 的研究进展和我们已有试验工作表明,最经济有效,具有实用价值,在生产上可获得成功是厌氧处理法。近10多年来,国外关于高 效厌氧处理技术研究进展迅速,并出现了多种多样的工艺设备,如高效厌氧生物反应器,并在实用化方面取得了很大成绩,建立了 生产性装置,达到了高负荷运行,效果良好。本试验是根据我们已有研究基础,针对我国国情,对小型制浆造纸厂水污染防治除了 开发碱回收及各种综合利用技术外,要特别加强废水(废液)实用技术研究的指导思想,本试验采用改进型的上流式厌氧污泥床反应 器,设计了两种试验方案,通过试验结果如下。1. 试验方案I—碱法草浆黑液酸化和厌氧发酵I号UASB反应器动态模型试验结果表 明:(1). 采用中温35℃±1℃高效厌氧反应器USAB内装有填料(陶粒)和三相分离器,具有保持高浓度生物量和防止污泥流失的特点 ,污泥浓度Vs 可达30%以上,因而具有高效、节能、产能、滞留期短的优点,当进水CODcr在7500-10000mg/l,HRT由7天缩短到3天 ,有机容积负荷在1.22gCODcr/l·d-3.43gCODcr/l·d时,CODcr平均去除率可达55%-45.5%,最高CODcr去除率可达60.2-63.5%, BOD5去除率可达75.9-83.2%,沼气容积产气率可达0.29-0.67l/l·d,每克CODcr转化为沼气产率达0.39-0.48l/gCODcr·d,CH4含量 65.8-75.5%。厌氧发酵出水再用化学法进行后处理脱除难降解的木质素,CODcr总去除率达80%以上。(2). 动态试验结果表明:采 用酸化—厌氧发酵处理黑液工艺合理,技术路线可行。2. 试验方案II—黑液用化学法(Hcl)去除木质素进行厌氧发酵,II号UASB反 应器动态模型试验结果表明:(1). 采用中温35℃±1℃高效厌氧反应器UASB(内有软填料),当进水CODcr7000-13000mg/l左右,HRT 由6天缩短到1天,有机负荷由0.98gCODcr/l·d增加到11gCODcr/l·d时,COD平均去除率均可稳定在70-77%,BOD5去除率为87.3- 93.1%,沼气容积产气率0.21-2.6l/l·d,每克CODcr转化为沼气产率为0.39-0.48l/gCODcr·d,高的可达0.53l/gCODcr·d,转化 率较高,CH4含量63-70%。(2). 试验证明碱法草浆黑液物化预处理—厌氧发酵处理的技术路线也是可行的,工艺合理、效果较好。 在有条件的工厂可采用。3.厌氧发酵阶段几大类群微生物计数表明:(1). 当发酵工艺和运行处于相对稳定状态时,微生物群体的 组成也达到相对的稳定,各类微生物之间保持动态平衡关系。当产乙酸菌的数量为107-108个/ml时,产甲烷菌的数量为105-106 个/ml,当产乙酸菌数量为106-107个/ml时,产甲烷菌的数量为103-105个/ml。(2).稳态运行条件下,黑液预处理为甲烷发酵创造 了有利的生态环境,获得了较好的处理效果和较高的COD转化为沼气的产率0.39-0.48l/g·CODcr·d,反应器中形成较为稳定而数 量较下水污泥中高1-2个数量级的厌氧发酵微生物区系组成。这一结果为黑液厌氧发酵提供了微生物理论依据。Paper industry is one of the important pollution source of water environment in our country. Its character of water pollution is many small factories, much grass pulp, disadvantageous technique, large preading area of pullution. Its effluent makes up 1/6 of whole country's industry wastwater. Its organic pollutant accounts 1/4 of whole country's. Alkaline grass paper pulp effluent with pollutants such as ligoin, remaining alkali sulfide, chloride besides organic material, is a kind of high concentrate organic wastewater which has high PH walug, dark colour and is difficult in treatment. There is urgent require to find ways to treat the wastewater. There are different ways to treat alkaline paper grass pulp effluent. According to the research advances and our experiment work, the most economical and useful way is anaerobic degradation which was advanced quick in last ten years. In the control of waste water of small pulp paper mill, the study of wastewater utilization technology should be emphasized, besides alkaline retrieving and different kinds of comprehensive utilization technology. Our experiment used modified UASB(Upflow Anaerobic Sludge Blanket Reactor). Two kinds of plan were disgned. The results are lined below. 1. The first experiment plant-aciding black pulp effluent and methanogenic digestion. The dynamic model experiment results of I-UASB reactor showed: (1)The mesophilic(35℃±1℃)high effect UASB reactor having haydite and threee state seperation in it had the character of keeping high bioimass concentration and preventing losss of sludge. It had advantages of high effect, energe saving, energe prodcing and short HRT(Hydroulic retention time). When the influent COD was 7500-10000mg, HRT was shortened from 7 days to 3days, organic loading rate was 1.22g-3.43COD/l· d, the average COD removal efficiency was 55%-45%. The highest COD efficiency was 60.2-63.5%, BOD removal of 75.9 -83.4% was achieved. Biogass production rate were up to 0.29-0.67l/l·d. Biogass converted efficiency from every gram of COD could reach 0.39-0.48l/gCOD·d. Methane content was 65.0-75.5%. Chemical method was used to deplate lignin in anaerobic digestion effluent. Total COD removal efficiency could be more than 80%. (2)Using aciding annaerobic digestion to treat the black effluent was reseanable in technique and technology. 2. The second experiment plan-anaerobic digestion was used after the chemical method was used to deplate lignin in the black effluent. The result of dynamic experiment of II-UASB reactor showed: (1)High effect mesophilic (35℃±1℃)UASB reactor having soft slaffing in was used. When influent COD was about 7000-13000mg/l, HRT was shortened from 6 days to 1 day and organic loading rate was increased from 0.90 to 11g COD /l·d, average COD removal efficiency remained stable on 70-77%. BOD, removal efficiency was between 87.3-93.1%. Biogass production rate was 0.2-2.6l/l ·d .Biogass converted efficiency from a gram of COD was 0.39-0.481/gCOD·d with the high value of 0.53l/gCOD·d. Methane content was 63-70%. (2)The way that using physical, chemical Pre-treatment-anaerobic digestion to treat alkaline black effluent is feasible and can be used in some factories when the condition exists. 3. Counting of several class of microoganisms in anaerobic digestion stage showed: (1)As the disgestion was in stable motion, the compositon of microorganic colony could get relative stable. Dynamic balance was remaining among different kinds of microorganism such as methanogenic bacteria, Acidogenic bacteria, sulfate reducing bacteria, and heterotrophic bacteria. (2)Under stable motion, the pre-treatment of black effluent produced favourable eco-enviroment for methanegenic digestion. Good treatment effect and high biogass convertent efficiency from COD(0.39-0.48l/g·COD· d)were gotten. Some stable and high quantity(10-100times more than sewage sludge)microorganism colony were formed in the reactor. This result provided theoretical basis for anaerobic digestion of black effluent.

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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.