Microorganism interaction in microbial community, metabolic behavior and biodegradation effect on bitumen

Area of Science:

• Microbiology
• Environmental Science
• Materials Science

Background:

• Understanding microbial interactions is crucial for biodegradation studies.
• Bitumen biodegradation impacts material properties and pavement performance.

Purpose of the Study:

• Investigate microorganism interactions and their effect on bitumen biodegradation.
• Analyze metabolic pathways, chemical changes, and property alterations during bitumen degradation.

Main Methods:

• Compounding specific microbial species: Pseudomonas putida, Sphingomonas polyaromaticivorans, Bacillus cereus, Pseudomonas fluorescens, and Bacillus subtilis.
• Analyzing microbial interactions, metabolic products, and pathways.
• Evaluating changes in bitumen's chemical composition, morphology, elemental content, microstructure, and micromechanical properties.

Main Results:

• Microorganisms exhibit synergy via substrate division and complementary metabolic functions.
• Bitumen biodegradation produces alcohols, phenols, carboxylic acids, and fatty acids.
• Degradation alters bitumen's chemical and elemental composition, reducing adhesion and increasing modulus, thus lowering service performance.

Conclusions:

• Microbial synergy drives bitumen biodegradation, leading to detrimental changes in material properties.
• Findings provide insights into bitumen biodegradation and a basis for extending pavement service life.