Bio-Survivor: Who Does It Better - Biobased Polymers or Microbial Consortia of the Baltic Sea?

Bio-Survivor: Who Does It Better - Biobased Polymers or Microbial Consortia of the Baltic Sea?

Abstract

As most plastic waste ends up in the sea, the marine industry is looking for sustainable alternatives to conventional plastics and bio-based polymers are being explored for use in equipment and components. However, their long-term stability in the ocean remains uncertain - especially if these materials are lost or dumped at sea. This study evaluates the resistance of these biobased polymers – namely poly(3-hydroxybutyrate) (PHB), poly(butylene succinate) (PBS) and poly(lactic acid) (PLA) – to degradation by marine microbial consortia from the Baltic Sea. The aim was to assess whether the materials could be degraded in marine environment by the sea microbial consortia, which could limit their durability and raise environmental concerns. Initial screening of degrading ability of the microorganisms was performed using agar plate tests with emulsified polymers to detect the formation of halozones. To better investigate the degradability, the polymer samples of solid polymers in granular or foil form (prepared by hot pressing or solvent casting) were exposed to microbial consortia. The structural changes were investigated by scanning electron microscopy (SEM), while the chemical and physical changes were monitored by differential scanning calorimetry (DSC) and gel permeation chromatography (GPC/SEC-MALS). The bacterial growth was monitored by optical density (OD) measurements and the corresponding bacterial strains were identified by MALDI-TOF and DNA sequencing. The results show that some bacteria naturally present in the Baltic Sea are able to degrade some biobased polymers. This suggests that if these materials enter the marine environment, they may not remain intact, which may not cause 'ghost fishing' if equipment is lost. While their biodegradability may provide environmental benefits in the case of waste, it may also pose a risk for long-term use in marine equipment if the materials are susceptible to microbial attack.

As most plastic waste ends up in the sea, the marine industry is looking for sustainable alternatives to conventional plastics and bio-based polymers are being explored for use in equipment and components. However, their long-term stability in the ocean remains uncertain - especially if these materials are lost or dumped at sea. This study evaluates the resistance of these biobased polymers – namely poly(3-hydroxybutyrate) (PHB), poly(butylene succinate) (PBS) and poly(lactic acid) (PLA) – to degradation by marine microbial consortia from the Baltic Sea. The aim was to assess whether the materials could be degraded in marine environment by the sea microbial consortia, which could limit their durability and raise environmental concerns. Initial screening of degrading ability of the microorganisms was performed using agar plate tests with emulsified polymers to detect the formation of halozones. To better investigate the degradability, the polymer samples of solid polymers in granular or foil form (prepared by hot pressing or solvent casting) were exposed to microbial consortia. The structural changes were investigated by scanning electron microscopy (SEM), while the chemical and physical changes were monitored by differential scanning calorimetry (DSC) and gel permeation chromatography (GPC/SEC-MALS). The bacterial growth was monitored by optical density (OD) measurements and the corresponding bacterial strains were identified by MALDI-TOF and DNA sequencing. The results show that some bacteria naturally present in the Baltic Sea are able to degrade some biobased polymers. This suggests that if these materials enter the marine environment, they may not remain intact, which may not cause 'ghost fishing' if equipment is lost. While their biodegradability may provide environmental benefits in the case of waste, it may also pose a risk for long-term use in marine equipment if the materials are susceptible to microbial attack.

GUZIUROVÁ, P.; KREMPASKÁ, V.; SEDLÁČEK, P.; SEDLÁŘ, K.; OBRUČA, S.

18.09.2025

Wydawnictwo uczelniane zapadopomorskiego uniwersitetu technolpogicznego w Szczcecinie

Szczecin

ISBN 978-83-7663-393

BALTIC BIOMAT 2025: From Materials Design to Advanced Structures

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https://balticbiomat.zut.edu.pl/fileadmin/Photo_gallery/2025/BalticBioMat_book_of_abstracts_2025_final.pdf