Microbial community acclimatization enhances bioplastics biodegradation and biogas production under thermophilic anaerobic digestion

Elisa Clagnan; Mirko Cucina; Raveena Vilas Sajgule; Patrizia De Nisi; Fabrizio Adani

doi:10.1016/j.biortech.2023.129889

Microbial community acclimatization enhances bioplastics biodegradation and biogas production under thermophilic anaerobic digestion

Bioresour Technol. 2023 Dec:390:129889. doi: 10.1016/j.biortech.2023.129889. Epub 2023 Oct 20.

Authors

Elisa Clagnan¹, Mirko Cucina², Raveena Vilas Sajgule³, Patrizia De Nisi³, Fabrizio Adani⁴

Affiliations

¹ Gruppo Ricicla labs., Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia (DiSAA), Università degli studi di Milano, Via Celoria 2, 20133 Milano, Italy; Department for Sustainability, Biotechnologies and Agroindustry Division, ENEA, Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Casaccia Research Center, Via Anguillarese 301, 00123 Rome, Italy.
² Gruppo Ricicla labs., Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia (DiSAA), Università degli studi di Milano, Via Celoria 2, 20133 Milano, Italy; National Research Council of Italy, Institute for Agriculture and Forestry Systems in the Mediterranean (ISAFOM-CNR), Via della Madonna Alta 128, 06128 Perugia, Italy.
³ Gruppo Ricicla labs., Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia (DiSAA), Università degli studi di Milano, Via Celoria 2, 20133 Milano, Italy.
⁴ Gruppo Ricicla labs., Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia (DiSAA), Università degli studi di Milano, Via Celoria 2, 20133 Milano, Italy. Electronic address: Fabrizio.Adani@unimi.it.

PMID: 37866767
DOI: 10.1016/j.biortech.2023.129889

Abstract

This paper reports the results of a novel study of microbial acclimatization for bioplastics anaerobic degradation and conversion into biogas. Three sequential anaerobic digestion (AD) runs were carried out to favour microbial acclimatization to two different bioplastics, starch-based (SBS) and polyactic-acid (PLA). AD of SBS and PLA bioplastics was favoured by the acclimatization of the inoculum to the substrate after each run of AD. SBS conversion into biogas increased by 52 % (from 94 to 143 NL kgVS^-1) and it was correlated with the enhanced growth of starch degrading bacteria such as Hydrogenispora, Halocella and Haloplasma. PLA anaerobic degradation increased by 97 % (from 395 to 779 NL_biogas kgVS^-1) and it was related to the acclimatization of known PLA-degraders such as Tepidimicrobium, Methanothermobacter and Tepidanaerobacter. Microbial acclimatization appears a suitable and low-cost strategy to enhance bioplastics circularity by promoting their anaerobic biodegradation and conversion into biogas.

Keywords: Anaerobic digestion; Biogas; Microbial acclimatization; Polylactic acid-based bioplastic; Starch-based bioplastic.

MeSH terms

Acclimatization
Anaerobiosis
Biofuels*
Bioreactors
Firmicutes
Methane
Microbiota*
Polyesters
Starch

Substances

Biofuels
Methane
Starch
Polyesters