Study on The Ability of Scenedesmus Obliquus In The Bio-Removal of Polyethylene Microplastics From Aquatic Environments and Optimization of The Bioremoval Effective Parameters

Sharif Vaghefi, Hesam; Mafigholami, Roya; Tavakoli, Omid; Moghimi, Hamid

doi:10.22112/jwwse.2025.493962.1423

Study on The Ability of Scenedesmus Obliquus In The Bio-Removal of Polyethylene Microplastics From Aquatic Environments and Optimization of The Bioremoval Effective Parameters

Articles in Press

Authors

Hesam Sharif vaghefi ¹

Roya Mafigholami ¹

Omid Tavakoli ²

Hamid Moghimi ³

¹ Faculty of Engineering, Islamic Azad University West Tehran Branch, Tehran, Iran.

² School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran.

³ Department of Microbiology, School of Biology, University of Tehran, Tehran, Iran.

10.22112/jwwse.2025.493962.1423

Abstract

Microplastics refer to plastic particles with a diameter of less than 5 millimeters, which create significant environmental problems due to their small size, the lack of sufficient technology for removal, and the potential to cause side effects. The microalga scenedesmus obliquus has the ability to secrete ligninolytic enzymes and exopolysaccharides, enabling it to degrade microplastics and utilize them as a carbon source. In the present study, by optimizing the cultivation conditions of scenedesmus obliquus, the growth rate of the microalgae was enhanced, and subsequently, the feasibility of polyethylene microplastics bioremoval and the effects of various parameters on this process were investigated. According to the results obtained, the highest percentage of polyethylene microplastic removal was achieved at an optical density of 1 for scenedesmus, a stirring speed of 150 rpm, and a microplastic size of 45 µm. Gel chromatography analysis showed that the molecular weight of the microplastic decreased by approximately 14% after bioremoval process. Additionally, FTIR analysis indicated that the removal of the carbonyl functional group in the wavelength range of 1400-1600 nm could be considered as a factor confirming the bioremoval of polyethylene microplastics.

Keywords

Bioremoval

Design expert

Microalgae

Microplastic

Polyethylene