Biotransformation of Acrylonitrile-Butadiene-Styrene Using Brevibacillus nitrificans isolated from Effective Microorganisms

Abstract

Plastic waste has accumulated extensively in the environment due to its widespread use across multiple sectors, resulting in serious ecological concerns. Among these materials, acrylonitrile-butadiene-styrene (ABS) plastic is one of the most prevalent. Addressing the limitations of current waste management practices, this study investigated the potential of beneficial microorganisms to mitigate plastic pollution. We report that the bacterial strain Brevibacillus nitrificans ABS-02, isolated from effective microorganisms, can depolymerize ABS films. B. nitrificans ABS-02 exhibited sustained growth in a carbon-free medium over a 30-day cultivation period, during which it utilized 0.9 +/- 0.1% of the ABS as a carbon source. SEM and EDS analyses revealed pronounced surface damage and localized oxygen accumulation on ABS films treated with the strain. FT-IR and XPS analyses further confirmed chemical modifications in the ABS, including the emergence of new peaks corresponding to O-H (3,800-3,600 cm-1) and N-H (3,250-3,350 cm-1) functional groups. A shift from the nitrile group (399.5 eV) to the amide group (399.7 eV) indicated acrylonitrile hydrolysis and subsequent amide formation. Changes in hydrophobicity and thermal stability corroborated these structural alterations. Furthermore, GC-MS analysis identified the major degradation intermediates, primarily pentan-3-ol and 4-phenylbuta-1,3-dienylbenzene, providing clear evidence of ABS depolymerization by B. nitrificans ABS-02. These results demonstrate that B. nitrificans ABS-02 is capable of accelerating the biotransformation of ABS. This study highlights the potential of microbial systems as effective biological tools for addressing persistent plastic pollution.