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排序方式: 共有335条查询结果,搜索用时 31 毫秒
1.
为检测鸡饲料和鸡粪中雌激素,优化其微生物降解条件,应用高效液相色谱(HPLC)法检测蛋鸡饲料和鸡粪中的雌激素,利用11种高效降解雌激素的单一菌株和等体积混合得到的菌群开展雌激素的降解实验。结果表明:只有蛋鸡鸡粪中含有雌二醇(E2),含量为230 ng·g-1。微生物菌群的降解率高于单一菌株,在27℃下,10 d内能够降解76%的E2。研究表明,蛋鸡鸡粪中有雌激素存在,微生物菌群对雌激素的降解率高于单一菌株。 相似文献
2.
为获得能够修复除草剂莠去津污染土壤的高效降解菌,采用摇瓶富集法、平板分离法从莠去津过量使用的土壤中分离得到降解菌SFAD3,通过形态学、生理生化特征观察以及16S rDNA和ITS序列分析进行种类鉴定,测定获得菌株的最适降解条件,并通过土壤接种和盆栽试验验证菌株对莠去津污染土壤的修复作用。结果表明,菌株SFAD3最终被鉴定为门多萨假单胞菌Pseudomonas mendocina,该菌株培养30 d时对污染土壤中50 mg/kg莠去津的降解率可达72.6%;菌株SFAD3在MM液体培养基中最适降解条件为温度37℃、pH 7、莠去津初始浓度6.25 mg/L、接种量2%,对莠去津降的降解率为50.0%~72.2%;与仅有莠去津的处理相比,添加有SFAD3发酵液的处理20 d后芝麻的株高、根长、湿重和干重能够显著恢复,并且该菌对芝麻还具有一定的促生作用。表明降解菌SFAD3在修复莠去津污染土壤方面具有潜在的应用价值。 相似文献
3.
从生产毒死蜱农药厂采集的活性污泥中分离筛选得到2株降解效率较高的毒死蜱降解菌,命名为D1、D3,根据表型特征、生理生化特性和16 S rRNA基因序列相似性分析,将其鉴定为苍白杆菌属(Ochrobactrum sp.)和副球菌属(Paracoccus sp.)细菌。2株菌以最佳配比(1∶1.25)混合施用时,与单菌相比,毒死蜱降解效率可提高12%~26%;以混合菌株为研究对象,发现其对毒死蜱最适降解温度为30℃,最适降解pH值为7.0,最适NaCl浓度为0.5%;混合菌株施入土壤后,可保持较高的定殖能力和降解效率。 相似文献
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Anuj Kumar Pavla Ryparovà Bohumil Kasal Stergios Adamopoulos Petr Hajek 《Wood material science & engineering》2020,15(1):57-63
ABSTRACTBamboo scrimber is one of the most emerging structural materials for future building applications and it possesses properties comparable to other natural wood-based engineered materials such as glulam, laminated veneer lumber and cross-laminated timber. The goal of this work was to study the decay resistance of bamboo scrimber against white-rot (Trametes versicolor) and brown-rot fungi (Serpula lacrymans). Bamboo scrimber samples were incubated in petri dishes with the wood-decaying fungi and the weight loss after 12 weeks was measured. The surface morphology of fungal-degraded bamboo scrimber was evaluated using optical microscopy. Based on the percentage weight loss, bamboo scrimber could be classified as highly resistant against bio-deterioration by white and brown-rot fungi. 相似文献
6.
本试验研究了污水回流比(R)对UASB反应器处理难生物降解的化工综合废水(BOD5/CODcr~O.3)运行性能的影响。结果表明:回流比对CODcr去除率影响明显,当R=2时(水力负荷率HLR为0.426m^3·m^-3d^-1,液体升流速UFV为0.0983m·h^-1),CODcr,最大去除率为60%,基质降解速率SDR为1.122kgCOD·m^-3d^-1。当R=3时(HLR 0.432m^3·m^-3d^-1,UFV 0.131m·h^-),CODcr最大去除率为62.2%,SDR为1.163kgCOD·m^-3d^1。回流作用强化了污染物与微生物细胞之间传质效果,可能是反应器运行性能提高的重要原因。另外,回流引起UASB反应器内部水力学特性发生改变,使基质浓度梯度减小且混合均匀,VFA的产生量减少,VFA积累引起的抑制作用被消除。 相似文献
7.
Rates of degradation of 2-propenyl isothiocyanate (PrITC), benzyl isothiocyanate (BeITC) and 2-phenylethyl isothiocyanate (2-PeITC) in a soil known to biodegrade methyl isothiocyanate (MITC) at an accelerated rate, but never previously exposed to the other ITCs, were higher (persistence in soil increased by 1150, 80 and 100%, respectively,) than in a similar non-degrading soil. The rate of degradation of the same three ITCs was significantly lower in sterilised (autoclaved) soils than in the degrading soil. These results indicate that the three ITCs are susceptible to enhanced cross-biodegradation in soils where enhanced biodegradation of MITC has been induced by use of metham sodium soil fumigant. When Brassica plant tissue containing sinigrin (2-propenyl glucosinolate) as the predominant glucosinolate (GSL) was added to the degrading soil, the amount of PrITC present after 24 h was significantly lower than in the non-degrading soil at the same amendment rates. The toxicity to an insect test organism of the PrITC produced from the biofumigant plant tissue was correlated with the concentration of PrITC measured in the two soils, with 67% more plant tissue required in the degrading soil to cause 100% mortality as in the non-degrading soil (3.0 vs 5.0 mg g−1). The effectiveness of biofumigation using ITC-producing Brassica plants may be diminished in soil suffering from enhanced biodegradation of MITC. 相似文献
8.
Mrklas Ole Chu Angus Lunn Stuart Bentley Laurence R. 《Water, air, and soil pollution》2004,159(1):249-263
The release of alkanolamines and glycols into the subsurface soils poses a potential hazard to the environment through impacted soil and groundwater. This study investigated aerobic and anaerobic biodegradability of monoethanolamine (MEA), ethylene glycol (MEG) and triethylene glycol (TEG). Significant levels of MEA (31 000 mg/kg), MEG (500 mg/kg) and TEG (2100 mg/kg) were successfully aerobically biodegraded in bioreactors. The aerobic slurry experiments suggested initial phosphate (P) limitation, as biodegradation rates increased by one order of magnitude after phosphate addition. Anaerobic decay of MEA, MEG and TEG was unaffected by P-addition. MEA, MEG and TEG degradation products such as acetate, ethanol and ammonium at about 75 000 mg/kg, 8100 mg/kg and 8800 mg/kg degraded completely and did not prevent aerobic biodegradation. This study confirms proposed biodegradation pathways of MEA, MEG, TEG and their breakdown products in natural soil and groundwater using indigenous microbes. Levels of contamination studied here are significantly higher than previously reported. 相似文献
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10.
稻草降解及产油菌的筛选 总被引:1,自引:0,他引:1
本文筛选出了六株纤维素降解菌,其中菌株f8在稻草固态发酵培养基中产CMC酶活和FPA酶活最大分别为260.32 U和18.90 U,经初步鉴定为康宁木霉。菌株f3既能降解纤维素,又能产油脂,且在PDA液体培养基上油脂产率达到25%。经初步鉴定为绿色木霉。 相似文献