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Updated: Jul 7, 2026
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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Changes in bacterial communities accompanied by aggregation in a fed-batch composting reactor.
Keiko Watanabe1, Norio Nagao, Tatsuki Toda
1Graduate School of Engineering, Soka University, 1-236, Tangi-cho, Hachioji, Tokyo 192-8577, Japan. kewatana@soka.ac.jp
Current Microbiology
|January 31, 2008
Summary
Fed-batch composting (FBC) reactor aggregation alters bacterial communities, decreasing beneficial aerobic bacteria and increasing anaerobic Staphylococcaceae. This impacts organic degradation efficiency in composting systems.
Area of Science:
- Microbiology
- Environmental Science
- Biotechnology
Background:
- Fed-batch composting (FBC) reactors can experience content aggregation over time.
- Aggregation disrupts decomposition reactions and alters microbial community structure.
- Understanding these shifts is crucial for optimizing composting processes.
Purpose of the Study:
- To compare bacterial community structures in FBC reactors under aggregated versus optimal conditions.
- To identify specific bacterial groups affected by reactor aggregation.
- To elucidate the impact of aggregation on the composting environment.
Main Methods:
- 16S rRNA gene clone analysis was employed to characterize bacterial communities.
- Phylogenetic analysis was used to determine the relationships of dominant bacterial groups.
- Bacterial communities were compared between aggregated and optimal FBC reactor conditions.
Main Results:
- Under optimal conditions, Bacillaceae (e.g., Bacillus spp.) dominated (98%).
- Aggregation significantly decreased Bacillaceae populations.
- Staphylococcaceae populations increased to 53% under aggregated conditions, including anaerobes/facultative anaerobes.
Conclusions:
- Aerobic Gram-positive bacteria are key to organic degradation in FBC reactors.
- Reactor aggregation creates anaerobic microenvironments, favoring the growth of specific bacterial communities like Staphylococcaceae.
- These shifts indicate a decline in composting efficiency due to aggregation.
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