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

Abstract

To understand microorganism interaction among different microbial species in a microbial community, metabolic behavior and biodegradation effect on bitumen, Pseudomonas putida, Sphingomonas polyaromaticivorans, Bacillus cereus, Pseudomonas fluorescens, and Bacillus subtilis were compounded. The interactions among microorganisms, their metabolic products and pathways, as well as the changes in chemical component, microscopic morphology, elemental content, microstructure and micromechanical properties during bituminous biodegradation were investigated. Results show that different microorganisms achieve mutual synergy through the division of substrate and complementary metabolic functions, promoting the degradation of bitumen and generating many alcohols, phenols, carboxylic acids, fatty acids, etc. This process causes the changes in chemical components and elemental contents of bitumen, as well as a reduction in bituminous adhesion and an increase in modulus, which lowers bituminous service performance. This study provides new insights into bituminous biodegradation, and offers theoretical basis for further prolonging the service life of bituminous pavement.