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Updated: Aug 2, 2026
07:59
Estimating Sediment Denitrification Rates Using Cores and N2O Microsensors
Published on: December 6, 2018
Nitrous oxide production by organisms other than nitrifiers or denitrifiers
1Departments of Crop and Soil Sciences and Microbiology and Public Health, Michigan State University, East Lansing, Michigan 48824.
Applied and Environmental Microbiology
|December 1, 1982
Summary
Certain microbes, including nitrate-respiring bacteria, yeasts, and fungi, produce nitrous oxide (N2O) from nitrate. Human breath also contains elevated N2O levels, potentially increasing after consuming nitrate-rich foods.
Area of Science:
- Microbiology
- Environmental Science
- Biogeochemistry
Background:
- Nitrous oxide (N2O) is a potent greenhouse gas.
- Understanding N2O production pathways is crucial for environmental monitoring and mitigation.
- Various biological sources of N2O require investigation.
Purpose of the Study:
- To identify and characterize biological sources of N2O production.
- To investigate N2O generation from nitrate reduction by different microorganisms.
- To explore N2O presence in non-microbial biological samples like plants and animal breath.
Main Methods:
- Incubation of various heterotrophic bacteria, yeasts, and fungi with nitrate.
- Analysis of N2O production and consumption.
- Detection of N2O in plant tissues and animal breath samples.
Main Results:
- Nitrate-respiring bacteria, some assimilatory nitrate-reducing bacteria (e.g., Azotobacter vinelandii), and certain yeasts/fungi produced N2O from nitrate.
- N2O production occurred primarily in the stationary phase.
- Nitrate-respiring bacteria were significant N2O producers.
- Plants did not produce N2O, but damaged tissues showed microbial N2O.
- Elevated N2O levels were detected in human breath, increasing post-meal.
Conclusions:
- Microbial nitrate metabolism is a key source of N2O.
- Specific microbial groups are more efficient N2O producers.
- N2O is present in human breath, influenced by diet.
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