Related Experiment Video
Updated: May 24, 2026

A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Adaptation of nitrifying microbial biomass to nickel in batch incubations
Chok-Hang Yeung1, Christopher A Francis, Craig S Criddle
1Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USA. chyeung@stanfordalumni.org
Abstract:
Nitrification-microbial oxidation of ammonia to nitrate-is sensitive to an array of inhibitors. Currently, little is known regarding the ecological processes that enable adaptation to inhibitors and recovery of nitrification. This study evaluated inhibition and recovery of nitrification in batch cultures of activated sludge incubated with different levels of nickel (Ni), a model inhibitor. Incubation with 1 mg/L of added Ni did not adversely affect nitrification, and little inhibition occurred at 5 and 10 mg/L Ni. Incubation with 50 mg/L Ni resulted in significant inhibition, decreased amoA transcript abundance, and delayed recovery of nitrification until amoA transcript abundance rebounded after 24 h. For this dosage, recovery of nitrification occurred without a significant change in ammonia-oxidizing bacteria (AOB) community structure. By contrast, incubation with 150 mg/L of added Ni strongly inhibited nitrification and delayed recovery until a shift in AOB community structure occurred after ∼6 weeks of incubation. The results indicate that inhibitor-resistant nitrifying cultures can be obtained from long-term batch incubations of decaying activated sludge incubated with high levels of added inhibitor.
More Related Videos
08:05Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
06:17Medium Preparation for the Cultivation of Microorganisms under Strictly Anaerobic/Anoxic Conditions
Published on: August 15, 2019
Related Concept Videos
Microbial Nutrition
Precipitation Gravimetry
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...
Metabolism of Chemolithotrophs
Inorganic Nitrogen Assimilation
Deep Sea Microbial Ecology
Microbial Mats