Related Experiment Video
Updated: Jan 30, 2026
15:19
Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
10.1K
Organic overloading affects the microbial interactions during anaerobic digestion in sewage sludge reactors
Guilherme H R Braz1, Nuria Fernandez-Gonzalez2, Juan M Lema1
1Department of Chemical Engineering, Institute of Technology, Universidade de Santiago de Compostela, Constantino Candeira s/n, 15782 Santiago de Compostela, Galicia, Spain.
Chemosphere
|February 2, 2019
Summary
Organic overloading of anaerobic digesters causes shifts in microbial communities, with specific bacteria groups increasing and decreasing. This study details these changes, crucial for managing digester stability during disturbances.
Area of Science:
- Microbiology
- Environmental Science
- Biotechnology
Background:
- Understanding microbial interactions in anaerobic digestion is vital for process stability.
- Process disturbances, like organic overloading, significantly impact microbiome structure and function.
- Limited data exists on how these disturbances affect microbial dynamics and community resilience.
Purpose of the Study:
- To investigate the effects of organic overloading on the anaerobic digestion microbiome in sewage sludge reactors.
- To characterize the microbial community structure and diversity during an induced acidosis event.
- To elucidate the microbial interactions and successional patterns under stress conditions.
Main Methods:
- Utilized two identical sewage sludge anaerobic reactors subjected to organic loading shock with glycerol waste.
- Monitored volatile fatty acids accumulation and pH changes over time.
- Employed network analysis to identify co-occurring microbial clusters and their dynamic behaviors.
- Characterized microbiome structure and diversity using molecular techniques.
Main Results:
- Organic overloading led to rapid volatile fatty acids accumulation and a shift in microbial dominance from Bacteroidales and Methanomicrobiales to Firmicutes and Methanosaeta sp.
- Network analysis revealed distinct microbial clusters with Veillonellaceae and Candidatus Cloacimonetes initially increasing, followed by Porphyromonadaceae and Chitinophagaceae as acidosis progressed.
- Methanogenesis failed at pH < 6, approximately 72 hours after the organic overload.
- Observed functional redundancy and niche specialization among microorganisms during the disturbance.
Conclusions:
- Organic overloading triggers a predictable succession of functionally redundant microorganisms in anaerobic digesters.
- Acidosis can occur without immediate methanogen decline, highlighting complex microbial responses.
- Detailed temporal analysis provides insights into microbiome dynamics essential for developing management strategies during process disturbances.
Related Concept Videos
01:19Major Organs of the Digestive System
9.3K
The digestive system is responsible for the ingestion of food, secretion of enzymes, mixing and digesting food, absorption of the nutrients and defecation. The human digestive system consists of two major parts: the gastrointestinal tract and the accessory digestive organs.
Gastrointestinal tract:
Gastrointestinal tract:
9.3K
00:57Carbohydrate Digestion
122.4K
Carbohydrate digestion and metabolism break down simple and complex carbohydrates from food into saccharides (i.e., sugars) for the body to use as energy. Carbohydrate digestion starts in the mouth during mastication, or chewing. The masticated carbohydrates remain intact in the stomach. Digestion resumes in the duodenum of the small intestine, where pancreatic alpha-amylase and brush border enzymes of the microvilli convert complex carbohydrates to monosaccharides. Finally, the monosaccharides...
122.4K
01:50What is Monogastric Digestion?
75.2K
The human body contains a monogastric digestive system. In a monogastric digestive system, the stomach only contains one chamber in which it digests food. Several other animal species also have monogastric digestive systems, including pigs, horses, dogs, and birds. This chapter, however, focuses on the human digestive system.
75.2K
01:06Lipid Digestion
99.2K
Lipids are large molecules that are generally not water-soluble. Since most of the digestive enzymes in the human body are water-based, there are specific steps the body must take to break down lipids and make them available for use.
99.2K
01:02Protein Digestion
110.9K
Protein digestion begins in the stomach, where the highly acidic environment can easily disrupt protein structure by exposing the peptide bonds of polypeptide chains. After polypeptide chains are broken into individual amino acids by a series of digestive enzymes, the amino acids are transported to the liver via the bloodstream to produce energy.
110.9K
01:31Accessory Organs
74.2K
Accessory organs are those that participate in the digestion of food but do not come into direct contact with it like the mouth, stomach, or intestine do. Accessory organs secrete enzymes into the digestive tract to facilitate the breakdown of food.
74.2K