果糖共代谢强化功能菌群/菌株降解活性黑5效能差异及机制比较

【背景】偶氮染料及其降解产物对生物具有高毒性和“三致”效应,利用共代谢强化纯培养细菌菌株或共培养混合菌群降解偶氮染料去除效能是一种环境友好型方法,但针对共基质调控下菌群/菌株的效能差异机制比较研究有待深入。【目的】考察果糖作为共基质强化功能菌群DDMZ1和功能菌株DDMZ1-1(经鉴定属于Burkholderia sp.)降解脱色活性黑5(reactive black 5, RB5)的效能差异机制。【方法】优化功能菌群/菌株培养条件,对果糖共代谢强化功能菌群/菌株的脱色性能及偶氮还原酶活性进行测定,通过液相色谱-飞行时间串联质谱联用仪(LC-TOF-MS)及植物毒性实验对RB5降解产物进行分析鉴定及毒性评估,并考察比较功能菌群/菌株对不同结构染料的广谱脱色性能。【结果】功能菌群DDMZ1和功能菌株Burkholderia sp. DDMZ1-1在优化条件下(pH 5.5, 37℃)对RB5的去除效率分别为79%和73%,而且功能菌群对高盐环境具有更强的适应优势。果糖的添加能够显著提升功能菌群/菌株对不同初始浓度RB5的脱色性能,特别是针对200 mg/L RB5的去除效率相较于不添加果...     

不同共代谢基质对活性黑5脱色菌群脱色性能及群落结构的影响

选择7种不同类别的共代谢基质,以功能菌群DDMZ1为初始菌群,以偶氮染料活性黑5为目标污染物,采用静置培养方式(兼氧培养)进行一系列静态批次实验,研究脱色功能菌群DDMZ1在不同共代谢基质(蔗糖、葡萄糖、果糖、葡萄糖+果糖、牛肉膏、蛋白胨、碳酸钠)作用下脱色性能及菌群群落结构的变化情况。脱色结果表明,添加果糖共基质能促进菌群脱色性能,对浓度为500 mg·L~(-1)的活性黑5作用72 h后,脱色率达到88.96%。高通量测序分析结果表明,活性黑5脱色菌群群落结构因添加的共代谢基质不同而明显不同。在微生物分类属水平上,Acinetobacter菌属在经蛋白胨、牛肉膏和碳酸钠作用后的样品中占据主导地位,而Lactococcus菌属和Burkholderia菌属则在经蔗糖、葡萄糖、果糖、葡萄糖+果糖作用后的样品中含量偏高。其中,乳球菌属Lactococcus在以果糖为共代谢基质样品中达到其最大比例,结合脱色结果推测乳球菌属Lactococcus是重要的优势功能菌属。综上可知,相对于初始菌群DDMZ1,有机氮源和无机碳源共基质对菌群的群落结构影响较小,糖类共基质对菌群的群落结构影响较大,其中果糖能更好地富集乳球菌属Lactococcus类脱色功能菌群,从而优化脱色功能菌群群落结构比例,促进菌群脱色效果。     

嗜盐菌群对酸性金黄G的脱色特性和机理

【目的】为了获得能够在高盐环境下脱色偶氮染料的嗜盐菌群及其降解机理。【方法】采用富集驯化的方法获得一个嗜盐菌群,采用Illumina HiSeq2500测序平台对其群落结构进行测定;采用分光光度法测定了其降解特性;采用GC-MS和红外图谱分析了其降解机理;采用微核实验的方法比较了偶氮染料降解前后的毒性。【结果】该菌群在10%的盐度下,使100mg/L的酸性金黄G在8h内脱色。菌群主要由Zobellella、Rheinheimera、Exiguobacterium和Marinobacterium组成。最适宜的脱色条件是:pH=6,酵母粉为碳源,蛋白胨或硝酸钾作为氮源,盐度为1%–10%。酸性金黄G降解产物的毒性比降解前降低。酸性金黄G主要的降解产物是对氨基二苯胺和二苯胺。此外,该菌群还能使酸性大红GR和直接湖蓝5B等多种偶氮染料脱色,具有较好的脱色广谱性。【结论】获得了快速降解偶氮染料的嗜盐菌群及降解机理,为该嗜盐菌群应用于高盐印染废水的处理提供菌种资源和理论支持。     

脱水污泥中脱色偶氮染料功能菌群的驯化分离

【目的】获得降解混合偶氮染料的高效降解菌,应用于印染行业偶氮染料废水的生物处理和资源化。【方法】以某污水处理厂的脱水污泥作为分离源,经偶氮染料废水驯化后,分离筛选出9株偶氮染料脱色株(命名为T-1-T-9),通过形态观察、生理特征及基于16S rRNA基因序列的分子生物学鉴定,初步认定分离株分属于芽孢杆菌属(Bacillus)、微小杆菌属(Exiguobacterium)、寡单胞菌属(Stenotrophomonas)和副球菌属(Paracoccus)。【结果】所得分离株纯培养均可不同程度地脱色单一偶氮染料和混合偶氮染料,其中T-8对甲基橙和金橙I的脱色速率最大,40 h的脱色率分别为85.9%和86.2%,T-8菌株干粉也可在无外源碳源的条件下完全脱色金橙I。分离株混合培养脱色混合偶氮染料的效率明显高于纯培养,可达90.1%。【结论】脱水污泥作为脱色偶氮染料功能菌群的新来源具有良好的应用价值。     

脱水污泥中脱色偶氮染料功能菌

近年来,随着印染与染料工业的发展,染料的数量和品种不断增多,由染料废水造成的污染呈增加的趋势,开发环境友好、高效、快速、低成本的染料废水处理方法是当前研究的热点。国内外常用的偶氮染料废水处理的方法可以分为物理法、化学法和生物法。传统的物化法虽然效果好,但较高的成本以及严重的二次污染,限制了其在实际中的应用,生物法以廉价、高效与环境友好等优势而广为应用。目前利用微生物处理偶氮染料废水的应用和研究居于首位,许多研究者致力于高效脱色偶氮染料微生物的筛选、分离和驯化[1-2]。本刊2014年第12期刊登了解井坤、花莉等的文章《脱水污泥中脱色偶氮染料功能菌群的驯化分离》[3]。作者以脱水污泥作为脱色偶氮染料功能菌群的新来源,经驯化分离获得降解混合偶氮染料的高效降解菌株若干,菌株所制备干粉也可在无外源碳源的条件下完全脱色金橙I,研究表明脱水污泥是耐胁迫工程菌株的理想种质来源。近年来该研究团队利用研究所得菌株,对脱水污泥处理不同偶氮染料废水的微生物群落结构进行了基于分子生物学的分析,得到了偶氮染料结构和功能群落结构组成的信息,研究结果表明偶氮染料结构同降解菌群落组成有对应关系,不同偶氮染料驯化下的混合微生物更倾向于形成以优势种群为主的特定微生物群落结构,而群落多样性在偶氮染料的脱色作用中不是主要因素[4];基于脱污污泥中分离得到的偶氮染料脱色菌种构建的聚氨酯泡沫固定化微生物体系,能够快速、反复用于偶氮染料废水的脱色[5]。由于实际偶氮染料废水的成分十分复杂,针对不同的偶氮染料废水构建特定的高效脱色微生物群落结构在实际中的应用有待进一步探究;其次本研究在固定化微生物的脱色过程中,采用的是较小的反应器,对于反应器放大后的脱色效果也需要进一步的研究。进行了脱色偶氮染料废水的微生物燃料电池体系的搭建和运行,证明分离株能够有效进行胞外电子传递,在脱色偶氮染料的同时实现产能资源化,同时说明脱水污泥也可作为保外电子呼吸菌的种质来源[6-7];在MFC同步脱色产电性能的研究中,虽然MFC加速了偶氮染料的脱色,但是其产电水平整体偏低,达不到有效利用水平,所以如何进一步提升产电能力从而到达有效利用水平也是亟待解决的问题。     

氧气对混合菌群脱色降解偶氮染料效果的影响

【背景】偶氮染料及其中间产物具有一定的环境毒性,利用混合菌群降解偶氮染料是一种环境友好型方法,但降解过程中氧气的存在起到至关重要的作用,可以促进或抑制偶氮染料的微生物降解作用。【目的】探讨氧气对偶氮染料微生物脱色液的影响,分析氧气对混合菌群脱色降解偶氮染料效果的影响。【方法】利用混合菌群DDMY1在3种培养条件(好氧、厌氧、兼氧)下,对7种偶氮染料进行脱色降解,探讨偶氮染料脱色液对氧气的响应情况,利用紫外可见分光光度法(ultraviolet visible spectrophotometry,UV-vis)和傅里叶变换红外光谱法(Fourier transform infrared spectroscopy,FTIR)对脱色产物进行分析。【结果】在兼氧和厌氧条件下反应48 h后的染料脱色液,与氧气充分接触后,部分偶氮染料微生物脱色液发生较为明显的复色现象,如活性黑5、直接黑38;UV-vis分析结果表明,这种复色现象是由于脱色液与氧气接触之后产生新物质所致;FTIR分析结果表明,混合菌群对发生复色反应的偶氮染料仍然具有一定脱色降解效果,但是脱色尚不够完全。【结论】兼氧和厌氧条件下,氧气对部分偶氮染料微生物脱色液具有较为明显的影响,从而影响混合菌群对偶氮染料的整体脱色效果,这可为今后研究偶氮染料彻底生物降解提供理论基础。     

共代谢条件下光合细菌对2-氯苯酚的生物降解

光合细菌PSB-1D不能利用2-氯苯酚(2-CP)作为唯一的碳源和能源.选用苹果酸、丙酸钠、乙酸钠、柠檬酸钠、苯酚、葡萄糖和可溶性淀粉等7种不同碳源作为光合细菌PSB-1D降解2-CP的共代谢基质,考察了在黑暗好氧培养条件下,不同共代谢基质对PSB-1D生长及降解2-CP效果的影响.结果表明:葡萄糖能够很好地促进PSB-1D的大量繁殖,提高降解效果,缩短降解周期,为最佳共代谢基质.对葡萄糖的投加浓度进行了优化,当葡萄糖的投加浓度为3 g·L-1时,菌株PSB-1D培养168 h后的菌体生长浓度△D560为1.749,2-CP的半衰期为3.9 d,降解速率常数为0.00864 h-1.采用SDS-PAGE对微生物全细胞蛋白质进行分析发现,在共代谢过程中当菌株PSB-1D利用葡萄糖作为底物提供能源和碳源时,可诱导产生2-CP特异性降解酶.     

红树林混合菌群协同降解偶氮染料活性黑5脱色性能研究

通过对福建省龙海市海门岛红树林保护区的近海沉积物样品进行富集驯化,得到了能够协同降解偶氮染料活性黑5的混合菌群HMD9-Q7。经过生化试验和16S rDNA序列分析,鉴定该混合菌群主要由越南蔷薇菌（Rossellomorea vietnamensis）、转化异源物食烷菌（Alcanivorax xenomutans）和近海生微泡菌（Microbulbifer maritimus）组成。与单一菌株相比较,混合菌群具有显著的脱色效果,可能因其菌株之间存在着相互协同促进作用。该混合菌群对含20~100 mg/L浓度的活性黑5均产生脱色作用。混合菌群HMD9-Q7可以广泛利用外加碳源和氮源,如葡萄糖、硝酸铵、牛肉膏等;NaCl浓度在5~30 g/L范围内都可对活性黑5进行脱色;在pH 7和温度30℃条件下脱色率最高。在最优条件下,该混合菌群在60 h内对活性黑5的脱色率可达到85%~90%。该新型混合菌群主要通过生物降解途径来实现对活性黑5的脱色。随着降解反应的发生,活性黑5的最大吸收峰逐渐变小直至完全消失,降解产物吸收峰位于近紫外光区。     

染料脱色菌与芳胺降解菌的筛选及降解染料研究

从印染厂废水处理系统的曝气池中分离到17株对多种染料有较高脱色能力的细菌,其脱色率都在80%以上,但偶氮染料脱色后产生的中间产物多数为无色的芳香胺类化合物,大多数细菌不能将其进一步降解。为此,通过富集培养和梯度驯化又筛选到一株以对硝基苯胺为唯一碳、氮源的菌株J18,该菌株虽对染料脱色能力很弱,却能够降解芳香胺类化合物。将芳香胺降解菌J18与染料脱色菌H两菌株混合培养,在最适条件下,结果使染料的脱色率和芳胺降解率均到达90%和85%以上,从而达到了彻底降解染料的目的。     

一株脱色真菌的鉴定及脱色特性的初步探讨

从废水环境中分离筛选到一株高效染料脱色真菌, 根据形态学及显微特征初步鉴定为泡盛曲霉(Aspergillus awamori), 命名为Asaw117; 从偶氮类、蒽醌类和氧醌类中选取8种不同染料进行脱色分析表明, 该菌株对0.1 g/L蒽醌类染料还原蓝RSN的脱色率可达100%; 采用不同培养基及不同种类碳氮源进行试验比较, 菌株在查氏培养基中生长慢, 但脱色效果最好, 在马铃薯培养基中生长旺盛, 脱色效果次之。此外, 菌株Asaw117能利用还原蓝RSN作为氮源, 但不能利用其为碳源; 几种碳氮源组合实验中, 菌株在蔗糖、硝酸铵组合的査氏培养基脱色效果为好。因此对处理印染废水具有较好的应用潜力。     

Degradation of azo dyes containing aminonaphthol by Sphingomonas sp strain 1CX

Sphingomonas sp strain 1CX was isolated from a wastewater treatment plant and is capable of aerobically degrading a suite of azo dyes, using them as a sole source of carbon and nitrogen. All azo dyes known to be decolorized by strain 1CX (Orange II, Acid Orange 8, Acid Orange 10, Acid Red 4, and Acid Red 88) have in their structure either 1-amino-2-naphthol or 2-amino-1-naphthol. In addition, an analysis of the structures of the dyes degraded suggests that there are certain positions and types of substituents on the azo dye which determine if degradation will occur. Growth and dye decolorization occurs only aerobically and does not occur under fermentative or denitrification conditions. The mechanism by which 1CX decolorizes azo dyes appears to be through reductive cleavage of the azo bond. In the case of Orange II, the initial degradation products were sulfanilic acid and 1-amino-2-naphthol. Sulfanilic acid, however, was not used by 1CX as a growth substrate. The addition of glucose or inorganic nitrogen inhibited growth and decoloration of azo dyes by 1CX. Attempts to grow the organism on chemically defined media containing several different amino acids and sugars as sources of nitrogen and carbon were not successful. Phylogenetic analysis of Sphingomonas sp strain 1CX shows it to be related to, but distinct from, other azo dye-decolorizing Sphingomonas spp strains isolated previously from the same wastewater treatment facility. Received 19 May 1999/ Accepted in revised form 11 August 1999     

海洋产电菌Shewanella marisflavi EP1的脱色特性

以一株新筛选得到的海洋产电菌Shewanella marisflavi EP1作为实验材料,研究了该菌株关于偶氮、蒽醌、三苯基甲烷等染料的脱色能力及脱色机制。结果表明,该菌株对这些染料均具有较好的脱色能力,最高脱色容量达到925 mg染料/(g细胞干重.d)。EP1能利用葡萄糖、蔗糖、木糖、乳酸、甲酸、柠檬酸等多种碳源将单偶氮染料丽春红2R脱色。脱色的pH、温度和NaCl浓度范围分别是:pH 6-10、15°C-40°C、0-8%。最优脱色条件:乳酸,pH 8、35°C、1%-2%NaCl,10 h内脱色率高达99.95%。分光光谱结果表明,在0-8%NaCl浓度范围内EP1脱色机制为降解脱色。     

The accelerating effect and mechanism of a newly functional bio-carrier modified by redox mediators for the azo dyes decolorization

In this study, a functional bio-carrier modified by redox meditors was developed as a redox mediator for application in azo dye decolorization processes. Its accelerating effect and mechanism for azo dyes decolorization were also examined. The decolorization rates of 10 azo dyes were enhanced about 1.5–3 fold by the functional bio-carrier modified with disperse turquoise blue S-GL, and the ORP value during the acid red GR decolorization process was changed to a more negative value of 20–25 mV. Non-dissolved redox mediator on the functional bio-carrier played a similar role as NADH during the azo dyes decolorization process. At the same time, the functional bio-carrier exhibited good reusability and the combinational technology of the redox mediator and bio-carrier was a great improvement of the redox mediator application and represents a new bio-treatment concept.     

Degradation kinetics of 4-amino naphthalene-1-sulfonic acid by a biofilm-forming bacterial consortium under carbon and nitrogen limitations

By decolorization of azo dyes, caused by reductive cleavage of the azo linkage, toxic or recalcitrant amines are generated. The present study deals with the effect of the inflowing medium composition (C:N ratio) on the kinetic behavior of a bacterial biofilm-forming consortium, able to use as carbon, nitrogen and sulfur source, the molecule of 4-aminonaphthalene-1-sulfonic acid (4ANS), which is one of the most recalcitrant byproducts generated by decolorization of azo dyes. All the experiments were carried out at room temperature in a lab-scale packed-bed biofilm reactor. Because environmental conditions affect the bioreactor performance, two mineral salts media containing 4ANS, with distinct C:N ratios; 0.68 (carbon as the limiting nutrient) and 8.57 (nitrogen as the limiting nutrient) were used to evaluate their effect on 4ANS biodegradation. By HPLC and COD measurements, the 4ANS removal rates and removal efficiencies were determined. The cultivable bacterial strains that compose the consortium were identified by their 16S rDNA gene sequence. With the enrichment technique used, a microbial consortium able to use efficiently 4ANS as the sole carbon source and energy, nitrogen and sulfur, was selected. The bacterial strains that constitute the consortium were isolated and identified. They belong to the following genera: Bacillus, Arthrobacter, Microbacterium, Nocardioides, and Oleomonas. The results obtained with this consortium showed, under nitrogen limitation, a remarkable increase in the 4ANS removal efficiency η(ANS), and in the 4ANS volumetric removal rates R (V,4ANS), as compared to those obtained under carbon limitation. Differences observed in bioreactor performance after changing the nutrient limitation could be caused by changes in biofilm properties and structure.     

A novel moderately halophilic bacterium for decolorizing azo dye under high salt condition

Halomonas sp strain GTW was newly isolated from coastal sediments contaminated by chemical wastewater and was identified to be a member of the genus Halomonas by 16S rDNA sequence analysis and physical and biochemical tests. The optimal decolorization conditions were as follows: temperature 30°C, pH 6.5.0–8.5, NaCl 10–20% (w/v) and the optimal carbon source was yeast exact. The results of experiments demonstrated that the bacteria could decolorize different azo dyes under high salt concentration conditions, and the decolorization rate of five tested azo dyes could be above 90% in 24 h. The exploitation of the salt-tolerant bacteria in the bio-treatment system would be a great improvement of conventional biological treatment systems and the bio-treatment concept.     

Isolation, identification and application of novel bacterial consortium TJ-1 for the decolourization of structurally different azo dyes

A novel bacterial consortium (TJ-1), which could decolorize Acid Orange 7 (AO7) and manyother azo dyes, was developed. In TJ-1 three bacterial strains were identified as Aeromonas caviae, Proteus mirabilis and Rhodococcus globerulus by 16S rRNA gene sequence analysis. AO7 decolorization was significantly higher with the use of consortium as compared to the use of individual strains, indicating complementary interactions among these strains. AO7 decolorization was observed under microaerophilic condition in the presence of organic carbon source. Either yeast extract (YE) alone or a combination of YE and glucose resulted in much higher decolorization of AO7 as compared to glucose alone, peptone or starch. Kinetic studies with different initial AO7 concentrations showed that more than 90% decolorization could be achieved even at 200mg/l within 16h. Fed-batch studies showed that AO7 decolorization required 10h during the first cycle and 5h in the second and third cycles, showing that bacterial cells could be used for multiple cycles. The consortium also decolorized fifteen other azo dyes individually as well as a simulated wastewater containing a mixture of all the sixteen azo dyes, thus, conferring the possibility of application of TJ-1 for the treatment of industrial wastewaters.