从制药厂废醪中回收蛋白质

采用凝聚沉降法从制药厂废醪中回收蛋白质。介绍了该法的原理、凝聚剂筛选和工艺条件试验情况。确定了最适宜的工艺条件：废醪等电点的ｐＨ为３．５,它与凝聚剂０．５ｍｉｌ／Ｌ硫酸铁铵溶液的适宜体积比约为（８０～１３０）：１。讨论了温度和时间对凝聚效果的影响。在适宜工艺条件下粗蛋白的回收率可达到９６％以上。     

蛋白质加合物作为分子生物标志物的分析研究

为了探索研究用人的静脉血中蛋白质 -环氧苯乙烯加合物作为人接触苯乙烯的分子生物标志物的可行性 ,用改进的 Ra-Ni方法分析测定蛋白质 -环氧苯乙烯加合物 .收集大白鼠鲜血与环氧苯乙烯体外反应的加合物样品 ,用定量苯乙烯 ,环氧苯乙烯染毒的大白鼠血样品和 2个现场接触苯乙烯的工人静脉血 (石棉厂 ,钢琴厂 )样品 ,测所有样品里的蛋白质加合物 .结果表明体外反应样品 ,所测的蛋白质 -环氧苯乙烯加合物与环氧苯乙烯剂量有较好的相关性 ;动物实验样品所测的蛋白质加合物分别与注射环氧苯乙烯 ,苯乙烯剂量呈较好的相关性 ;现场人群的样品 ,所测石棉厂的人群血中蛋白质加合物与接触苯乙烯剂量有一定的相关性 ,而钢琴厂的人群血样中所测的蛋白质加合物与接触苯乙烯剂量相关性不明显 .根据蛋白质 -环氧苯乙烯加合物与剂量的关系 ,初步确认用血红蛋白中的半胱氨酸 -环氧苯乙烯加合物作为人接触苯乙烯的分子标志物有可行性 .同时为用蛋白质 -环氧苯乙烯加合物作为人接触低浓度苯乙烯的分子生物标志物提供可靠的现场实验数据 .     

柠檬酸有机废水的生化处理研究

采用柠檬酸废水→培养饲料酵母→可溶化槽→光合细菌(PSB)槽→活性污泥工艺流程处理柠檬酸废水,实验结果表明,技术可行:原废水中COD_(Cr)和BOD_5的总去除率达98％以上,达国家GB8978-88排放标准;干酵母获得率1.0-1.2％,蛋白质含量46.58％;COD_(Cr)负荷达6kg/(m~3.d);TVA利用率达95％以上.本实验还筛选到对高浓度有机废水具较高同化能力的PSB混合菌种.     

无排泥运行下膜生物反应器的硝化代谢产物及细菌活性

采用膜生物反应器处理人工配制的无机NH₄⁺-N废水,在NH₄⁺-N浓度为500mg/L、无排泥条件下运行200d(HRT从30h逐步降至7h),系统内污泥浓度从最初的4 500mg/L上升至10 500mg/L.但是,单位污泥中以INTF吸光值表达的活性硝化菌数并未增加,从最初的23×10^-3降至1×10^-3;总NH₄⁺-N转化速率也从2.1kg/(L·d)降至1.5kg/(L·d).同时,反应器中胞外分泌产物(ECP)(糖和蛋白之和反应)从300 mg/L升至600mg/L. 利用上清液以及ECP提取液进行的批量试验结果表明,ECP过多抑制了硝化细菌活性.     

不同稳定剂对污泥蛋白发泡特性的影响研究

污泥含有蛋白质,经过高温水解可产生水解蛋白液(简称污泥蛋白),该蛋白具有发泡特性,经通风搅拌可产生泡沫;由于污泥蛋白所产生的泡沫具有不稳定、易破裂的特点,因此,设计了不同稳定剂对污泥蛋白发泡特性的影响研究实验,解决污泥蛋白所产生泡沫的稳定性问题。结果表明,在测定污泥蛋白的基本发泡特性实验中,10 mL污泥蛋白稀释10倍时,初始泡沫量较大,达到2 153 mL,但泡沫半衰期相对较短,时间为27 min;在10 mL污泥蛋白中分别加入0.2 g十六烷基三甲基溴化氨(CTAB)、羧甲基纤维素钠(CMC)、GP-1,并用水稀释10倍,制成泡沫后的初始泡沫量分别为1 380、1 400和1 248 mL,相对降低了773、753和905 mL;泡沫半衰期分别为31、76和509 min,相对提高了4、49和482 min,尤其是GP-1作为稳定剂时,泡沫的半衰期与不加稳定剂时相比提高了15倍;在10 mL污泥蛋白中加入0.2 g十六烷基三甲基溴化氨与0.2 g GP-1的复配稳定剂,用水稀释10倍,制成泡沫后的初始泡沫量为1 525 mL,相对降低了628 mL;泡沫半衰期为95 min,相对提高了68 min。因此,GP-1是污泥蛋白最好的泡沫稳定剂。     

三菌复合发酵提高厨余真蛋白含量的研究

为改善厨余发酵的品质,增加发酵后产品蛋白含量。采用三菌复合对厨余进行发酵,探讨了三菌复合的比例、接种量、发酵时间、初始pH值对发酵效果的影响,采用L9(34)正交实验对发酵条件进行优化,并对实验菌Lc和Ydy进行16S rRNA及18S rRNA分子鉴定。结果表明,最佳发酵条件为:菌剂配比(Lc∶Ydy∶S1)为3∶2∶1,接种量为0.15%,初始pH值为5.0,发酵时间为48 h。扩大实验结果表明,在最优发酵条件下,厨余经发酵后品质得到改善,真蛋白含量由发酵前的15.42%上升到发酵后的22.47%,增加率为45.80%;发酵后大肠菌群下降到30 cfu/g以下;乳酸菌及酵母菌数量分别为1.5×109 cfu/g和6.6×108 cfu/g。分子测序及鉴定结果表明,Lc为乳酸乳球菌,Ydy为热带假丝酵母菌。     

光-Fenton氧化破解剩余污泥和改善污泥脱水性能

利用紫外光-Fenton（光-Fenton）氧化处理城市剩余污泥,通过上清液的SCOD、多聚糖以及蛋白质浓度表征污泥胞外聚合物（EPS）的破解情况,通过污泥过滤比阻（SRF）和滤饼含水率表征污泥脱水性能的变化。结果表明,光．Fenton氧化破解污泥EPS和改善污泥脱水性能的效能明显优于单独Fenton反应和单独紫外光照射处理。pH为3、反应时间为2h,H2O2投加量为4g／L和Fe^2＋投加量为0．6mg／L是光-Fenton氧化处理供试污泥的适宜条件。在适宜处理条件下,污泥上清液中的SCOD、多聚糖和蛋白质浓度分别由67．46mg／L、12．53mg／L和8．62mg／L增加到568．12mg／L、448．62mg／L和292．94mg／L;SRF和滤饼含水率分别由2．4×10^S2／g和88．52％下降至5．26×10^8S^2／g和76．36％。光-Fenton反应在有效破懈污泥的同时,提高了污泥的脱水性能．有利于污泥的减量化。     

Effectiveness of novel and traditional treatments on the performance of incinerator bottom ash waste

Management of natural aggregate resources has become one of the most important challenges in construction, especially for high demand applications such as roads. Incinerator bottom ash (IBA), which is produced from burning domestic waste, has been considered a useful solution to the shortage of natural resources. In this research, IBA was mixed with limestone to produce an acceptable blend for use as a road foundation layer. Novel and traditional additives were adopted to improve the mechanical properties of IBA blends. The study focused on the treatment effect of additives on the mechanical characteristics of IBA blends under monotonic and cyclic triaxial stresses. The investigation evaluated fundamental material properties, including resilient modulus, initial Young's modulus and Poisson's ratio. Two nonlinear empirical models were adopted to depict the experimental resilient modulus results of the IBA blends. An approach has been proposed to predict realistic and representative values of resilient modulus for the material. In addition, a new relationship has been established between Young's modulus, resilient modulus and Poisson's ratio. Triaxial test results revealed that additives are more efficient with the control limestone blend than with the IBA blends. Novel additives, such as enzyme I and silica fume, produced a noticeable improvement in IBA properties in comparison to traditional additives.     

Reduction of U(VI) by the deep subsurface bacterium, Thermus scotoductus SA-01, and the involvement of the ABC transporter protein

In this study we investigated the effect of uranium on the growth of the bacterium Thermus scotoductus strain SA-01 as well as the whole cell U(VI) reduction capabilities of the organism. Also, site-directed mutagenesis confirmed the identity of a protein capable of a possible alternative mechanism of U(VI) reduction. SA-01 can grow aerobically in up to 1.25 mM uranium and has the capability to reduce low levels of U(VI) in under 20 h. TEM analysis performed on cells exposed to uranium showed extracellular and membrane-bound accumulation of uranium. The reductase-like protein was surprisingly identified as a peptide ABC transporter, peptide-binding protein. This study showcases the concept of protein promiscuity, where this protein with a distinct function in situ can also have the unintended function of a reactant for the reduction of U(VI).     

Alterations of protein profile in zebrafish liver cells exposed to methyl parathion: a membrane proteomics approach

Methyl parathion (MP) is an extensively used organophosphorus pesticide, which has been associated with a wide spectrum of toxic effects on environmental organisms. The aim of this study is to investigate the alterations of membrane protein profiles in zebrafish liver (ZFL) cell line exposed to MP for 24 h using proteomic approaches. Two-dimensional gel electrophoresis revealed a total of 13 protein spots, whose expression levels were significantly altered by MP. These differential proteins were subjected to matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry analysis, and nine proteins were identified to be membrane proteins, among which seven were up-regulated, while two were down-regulated. In addition, the mRNA levels corresponding to these differential membrane proteins were further analyzed by quantitative real-time PCR. And the differential expression of arginase-2 was specially validated via Western blotting. Regarding the physiological functions, these proteins are involved in molecular chaperon, cytoskeleton system, cell metabolism, signal transduction, transport and hormone receptor respectively, suggesting the complexity of MP-mediated toxicity to ZFL cell. These data could provide useful insights for better understanding the hepatotoxic mechanisms of MP and develop novel protein biomarkers for effectively monitoring MP contamination level in aquatic environment.