Chemosphere 308 (2022) 136410 Available online 14 September 2022 0045-6535/© 2022 Elsevier Ltd. All rights reserved. A novel study on the effectiveness of biofocculant-producing bacteria Bacillus enclensis, isolated from biofoc-based system as a biodegrader in microplastic pollution Zuhayra Nasrin Ahmad Shukri a , Che Engku Noramalina Che Engku Chik a , Shahadat Hossain a , Rohisyamuddin Othman a , Azizah Endut c , Fathurrahman Lananan d , Iber Benedict Terkula a , Amyra Suryatie Kamaruzzan a , Ahmad Ideris Abdul Rahim a , Ahmad Shuhaimi Draman a , Nor Azman Kasan a, b, * a Higher Institution Centre of Excellence (HICoE), Institute of Tropical Aquaculture and Fisheries, Universiti Malaysia Terengganu, 21030, Kuala Nerus, Terengganu, Malaysia b Microplastic Research Interest Group (MRIG), Universiti Malaysia Terengganu, 21030, Kuala Nerus, Terengganu, Malaysia c Faculty of Innovative Design and Technology, Universiti Sultan Zainal Abidin, Gong Badak Campus, 21300, Terengganu, Malaysia d East Coast Environmental Research Institute (ESERI), Universiti Sultan Zainal Abidin, Gong Badak Campus, 21300, Terengganu, Malaysia HIGHLIGHTS • B.enclensis was identifed as biofocculant-producing bacteria based on morphological and focculating activity. • Biofocculant-producing bacteria, B. enclensis yielded 93% of focculation effciency. • Microplastics was incubated with B. enclensis, changes in physical and chemical properties were observed by SEM and FTIR. • The microplastics served as the sole source of carbon for the bacterial culture that was grown in Mineral Salt Medium. • Inoculation of B. enclensis with microplastics provide eco-friendly treatment for microplastic pollution in aquaculture. A R T I C L E INFO Handling editor: Veeriah (Jega) Jegatheesan 1. Introduction Biofoc technology is an environment friendly aquaculture concept that allows high density aquaculture production with less or no water exchange (Emerenciano et al., 2017). In this system, the water column develops an aggregate of microbes, algae, and protozoa, as well as detritus and dead organic particles (Avnimelech, 2009). The primary goal of the biofoc technology is to recycle nutrients by keeping a high carbon to nitrogen (C/N) ratio in water in order to encourage the growth of heterotrophic bacteria that convert ammonia into new microbial mass production (Avnimelech, 2009; Widanarni et al., 2012). Subsequently, the microbial biomass would agglutinate together with other microbial communities and suspended particles in the water, creating a substance known as “foc” which the cultured organisms would then consume in-situ (Kuhn et al., 2010). The implementation of biofoc technology has the potential to improve aquaculture productivity, hence contribute to the attainment of sustainable aquaculture production (Zaki et al., 2014). Various taxonomic genera of microorganisms, such as Bacillus. infantis, * Corresponding author. Higher Institution Centre of Excellence (HICoE), Institute of Tropical Aquaculture and Fisheries, Universiti Malaysia Terengganu, 21030, Kuala Nerus, Terengganu, Malaysia. E-mail addresses: zuhayranasrin9723@gmail.com (Z.N. Ahmad Shukri), engkuamalina@gmail.com (C.E.N. Che Engku Chik), shahadatshuvo193@gmail.com (S. Hossain), din@umt.edu.my (R. Othman), enazizah@unisza.edu.my (A. Endut), fathurrahman@unisza.edu.my (F. Lananan), benedictiber@gmail.com (I.B. Terkula), amyra@umt.edu.my (A.S. Kamaruzzan), a.ideris@umt.edu.my (A.I. Abdul Rahim), armie@umt.edu.my (A.S. Draman), norazman@umt.edu.my (N.A. Kasan). Contents lists available at ScienceDirect Chemosphere journal homepage: www.elsevier.com/locate/chemosphere https://doi.org/10.1016/j.chemosphere.2022.136410 Received 6 June 2022; Received in revised form 5 September 2022; Accepted 7 September 2022