白腐真菌体对菲和芘的吸附-脱附作用及影响因素

为准确了解生物修复过程中多环芳烃(PAHs)的生物吸附行为,采用化学方法(脱蜡、皂化)分离白腐真菌样品并制得3个组分,探讨了白腐真菌组分的结构特征.同时,用批量平衡法研究了菲和芘在白腐真菌样品上的生物吸附-脱附行为及共存重金属Cu2+对吸附作用的影响,探讨了PAHs生物吸附的作用机制及构-效关系.结果表明,菲和芘在白腐真菌体上的等温吸附-脱附曲线均呈线性(Freundlich,N=1),为可逆吸附过程,其生物吸附机理为PAHs在白腐真菌体上的分配作用;经脱蜡和皂化后,菲在白腐真菌体上的分配系数Kp(F1)分别为Kp(F2)和Kp(F3)的4.5倍和7.5倍,芘的分配系数Kp(F1)则分别为Kp(F2)和Kp(F3)的3.8倍和7.2倍,表明主要分配介质为白腐真菌体上的脂类和聚酯类物质;PAHs的有机碳标化的分配系数Koc值与白腐真菌体的极性指数(O+N)/C呈反比.共存Cu2+离子促进白腐真菌体对菲的生物吸附,随着Cu2+浓度的增加,菲的生物吸附作用逐渐增强;增强吸附机制为Cu2+通过配合作用吸附到白腐真菌体上中和微生物表面的负电荷,降低白腐真菌体表面的亲水性,进而提高其疏水性分配作用;同时,吸附态Cu2+与菲之间形成阳离子-π键等特殊作用,其作用大小随白腐真菌体的极性指数(O+N)/C增大而降低.     

植物废料应用于白腐真菌处理难降解有机污染物

综述了植物废料在白腐真菌处理难降解有机污染物反应体系中的应用优势以及研究现状,指出目前国内外相关研究存在的问题主要集中在植物废料的选材、投量、染菌以及废渣最终处理等方面,因此解决以上方面中的瓶颈将是今后植物废料固定化白腐真菌处理难降解有机污染物的主要研究方向。     

Characteristics of the microbial communities in the integrated vertical-flow constructed wetlands

Microorganisms play an important role in removing pollutants from constructed wetlands. We investigated the microbial characteristics in a novel integrated vertical-flow constructed wetland (IVCW), which has been in operation in Wuhan, China since 1998. We used phospholipid fatty acid (PLFA) and amoA gene to analyze the structure and diversity of the microbial community within the IVCW. PLFA results suggested that the amount of bacterial PLFA was significantly higher than that of fungal PLFA, but the total microbial biomass represented by PLFA index was low in the system. Microbial spatial distribution showed significantly higher bacterial (both G⁺ and G⁻) and fungal biomass in the surface than in the subsurface layers. The ratios of monounsaturated to branched PLFA demonstrated that an anaerobic layer sandwiched by two aerobic layers existed in the IVCW, consistent with the redox potential results. Analysis of the amoA revealed the presence of Nitrosomonas-like sequences in the surface substrate of the downflow chamber and apparent diversities of ammonia-oxidizing bacteria in the system. These results suggest that microorganisms, despite their relatively low biomass, have inhabited the IVCW, and the results will offer some valuable information on microbe to system designers and managers.     

真菌滤塔启动及降解甲苯能力研究

生物法对于处理挥发性有机废气是一种经济和环境友好的处理工艺。研究在酸性条件下处理含甲苯气体,考察在不同进气浓度和入口负荷下真菌滤塔降解甲苯的能力。实验选用处理焦化废水的污泥作为真菌菌源,采用高浓度气态挂膜法,启动周期为12天,在pH=5的条件下运行2个月,以NO3--N为氮源能很好地去除高负荷甲苯气体,并且可以长期稳定高效运行。     

不同磷石膏添加量与接种菌根对玉米生长及磷、砷、硫吸收的影响

通过盆栽模拟试验研究了不同磷石膏（PG）添加量（0、20、40g·kg-1）和接种3种丛枝菌根真菌（Glomus mosseae（GM）、Glomus aggregatum（GA）、Diversispora spurcum（DS））对玉米生长及其磷、硫、砷吸收的影响.试验结果表明：随磷石膏添加量的提高,土壤有效磷、有效...     

Optimization of process parameters using response surface methodology for bioconversion of activated sludge by Penicillium corylophilum

The optimization of process parameters for the bioconversion of activated sludge by Penicillium corylophilum was investigated using response surface methodology （RSM）. The three parameters namely temperature of 33℃, agitation of 150 r/min, and pH of 5 were chosen as center point from the previous study of fungal treatment. The experimental data on chemical oxygen demand （COD） removal （%） were fitted into a quadratic polynomial model using multiple regression analysis. The optimum process conditions were determined by analyzing response surface three-dimensional surface plot and contour plot and by solving the regression model equation with Design Expert software. Box-Behnken design technique under RSM was used to optimize their interactions, which showed that an incubation temperature of 32.5℃, agitation of 105 r/min, and pH of 5.5 were the best conditions. Under these conditions, the maximum predicted yield of COD removal was 98.43%. These optimum conditions were used to evaluate the trail experiment, and the maximum yield of COD removal was recorded as 98.5%.     

一株能同时降解邻苯二甲酸二丁酯(DBP)和氰戊菊酯真菌的分离、鉴定及降解特性的初步研究

采用富集培养法从农田土壤中筛选出1株可同时降解邻苯二甲酸二丁酯(DBP)和氰戊菊酯的真菌DY4,经形态、生理生化特征及26S r DNA序列分析,初步鉴定为地霉属(Geotrichum sp.)霉菌,并在纯培养条件下研究了该菌株的最优降解条件和降解特性.结果表明,菌株DY4可利用DBP或氰戊菊酯作为唯一碳源,DBP、氰戊菊酯单一存在时,7 d对50 mg·L-1DBP的降解率(84.13%)高于氰戊菊酯(37.07%)的;DBP、氰戊菊酯共存时,对DBP的降解率明显降低,可能是农药对微生物的毒害作用所致.正交试验得到菌株DY4的最优降解条件为无外加碳源、DBP和氰戊菊酯的初始浓度25 mg·L-1、p H 7.5,在此条件下,7 d对DBP和氰戊菊酯的降解率达到65.36%和55.77%,降解反应符合一级动力学方程模型,两者的半衰期为4.46和6.88 d.     

细数5种你该洗却从不洗的生活用品

<正>1.枕头起床的时候有些鼻塞或轻微的头疼?英国的一项研究发现,不管是新枕头还是旧枕头,在其中都有至少一两种导致哮喘或其他疾病的细菌,有些甚至有十几种极微小的爬虫。死亡的皮肤细胞、螨虫、真菌、细菌都是常见的枕头"居民"。同时研究还有个惊人的发现:合成纤维枕头比传统羽绒枕头上有更多的有害物质,因为合成纤维不像天然的那样紧密。     

Investigation of factors on a fungal biofilter to treat waste gas with ethyl mercaptan

IntroductionOff gasescontainingVOCandodorsmaydogreatharmtoenvironmentandpeople’shealth .Therearemanymethodsfortreatingthem ,suchasphysicalmethods ,chemicalmethodsandbiologicalmethods.Biologicalmethodsarewidelyappliedintheprocessofoff gasespurificationfor…     

分子生物学技术在菌根研究中的应用及其进展

近几年来,菌根分子生物学得到了较快发展;尤其是一些用于首根真菌ITS区域的特异引物先后设计并合成成功,进一步推动了菌根学在分子水平上的研究。分子生物学技术在留根真菌分类鉴定及亲缘关系研究上应用较多。在菌根菌竟争性和持续性研究上．DNA分析技术已成为最重要的研究手段之一。在这些研究中,专为菌根真菌ITS区域分析而设计的ITS1-F和ITS4-B两种特异引物应用最为普遍。本文对菌根DNA分析技术、PCR－RFLP技术做了简单介绍;综述了PCR、ITh－RFLP等分析技术在菌根菌分类、亲缘关系及菌种持续性等方面的研究和应用情况。