1.Development and Evaluation of the Quick Anaero-system-A New Disposable Anaerobic Culture System.
Nam Woong YANG ; Jin Man KIM ; Gwang Ju CHOI ; Sook Jin JANG
The Korean Journal of Laboratory Medicine 2010;30(2):133-137
BACKGROUND: We developed a new disposable anaerobic culture system, namely, the Quick anaero-system, for easy culturing of obligate anaerobes. METHODS: Our system consists of 3 components: 1) new disposable anaerobic gas pack, 2) disposable culture-envelope and sealer, and 3) reusable stainless plate rack with mesh containing 10 g of palladium catalyst pellets. To evaluate the efficiency of our system, we used 12 anaerobic bacteria. We prepared 2 sets of ten-fold serial dilutions of the 12 anaerobes, and inoculated these samples on Luria-Bertani (LB) broth and LB blood agar plate (LB-BAP) (BD Diagnostic Systems, USA). Each set was incubated in the Quick anaero-system (DAS Tech, Korea) and BBL GasPak jar with BD GasPak EZ Anaerobe Container System (BD Diagnostic Systems) at 35-37degrees C for 48 hr. The minimal inoculum size showing visible growth of 12 anaerobes when incubated in both the systems was compared. RESULTS: The minimal inoculum size showing visible growth for 2 out of the 12 anaerobes in the LB broth and 9 out of the 12 anaerobes on LB-BAP was lower for the Quick anaero-system than in the BD GasPak EZ Anaerobe Container System. The mean time (+/-SD) required to achieve absolute anaerobic conditions of the Quick anaero-system was 17 min and 56 sec (+/-3 min and 25 sec). CONCLUSIONS: The Quick anaero-system is a simple and effective method of culturing obligate anaerobes, and its performance is superior to that of the BD GasPak EZ Anaerobe Container System.
Bacteria, Anaerobic/*growth &development
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Bacteriological Techniques/instrumentation/methods
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Culture Media/chemistry
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Gases/chemistry
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Palladium/chemistry
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Reagent Kits, Diagnostic
2.Structure relationship of nitrochlorobenzene catalytic degradation process in water over palladium-iron bimetallic catalyst.
Shao-feng NIU ; Hong-yi ZHOU ; Xu-ping AO ; Xin-hua XU ; Zhang-hua LOU
Journal of Zhejiang University. Science. B 2006;7(7):548-552
Two isomers of nitrochlorobenzene (o-, and p-NCB) were treated by a Pd/Fe catalyst in aqueous solutions through catalytic amination and dechlorination. Nitrochlorobenzenes are rapidly converted to form chloroanilines (CAN) first through an amination process, and then rapidly dechlorinated to become aniline (AN) and Cl(-), without the involvement of any other intermediate reaction products. The amination and dechlorination reaction are believed to take place predominantly on the surface site of the Pd/Fe catalysts. The dechlorination rate of the reductive degradation of the two isomers of nitrochlorobenzene (o-, and p-NCB) in the presence of Pd/Fe as a catalyst was measured experimentally. In all cases, the reaction rate constants were found to increase with the decrease in the Gibbs free energy (correlation with the activation energy) of NCBs formation; the activation energy of each dechlorination reaction was measured to be 95.83 and 77.05 kJ/mol, respectively for o- and p-NCB. The results demonstrated that p-NCBs were reduced more easily than o-NCBs.
Catalysis
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Industrial Waste
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prevention & control
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Iron
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chemistry
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Isomerism
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Kinetics
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Metals
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chemistry
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Nitrobenzenes
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chemistry
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Palladium
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chemistry
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Structure-Activity Relationship
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Waste Disposal, Fluid
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methods
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Water
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chemistry
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Water Purification
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methods