TY - JOUR

T1 - Setting new standards

T2 - Multiphasic analysis of microplastic mineralization by fungi

AU - Rohrbach, Stephan

AU - Gkoutselis, Gerasimos

AU - Mauel, Anika

AU - Telli, Nihal

AU - Senker, Jürgen

AU - Ho Kah Wye, Adrian

AU - Rambold, Gerhard

AU - Horn, Marcus Andreas

PY - 2024/2

Y1 - 2024/2

N2 - Plastic materials provide numerous benefits. However, properties such as durability and resistance to degradation that make plastic attractive for variable applications likewise foster accumulation in the environment. Fragmentation of plastics leads to the formation of potentially hazardous microplastic, of which a considerable amount derives from polystyrene. Here, we investigated the biodegradation of polystyrene by the tropical sooty mold fungus Capnodium coffeae in different experimental setups. Growth of C. coffeae was stimulated significantly when cultured in presence of plastic polymers rather than in its absence. Stable isotope tracing using 13C-enriched polystyrene particles combined with cavity ring-down spectroscopy showed that the fungus mineralized polystyrene traces. However, phospholipid fatty acid stable isotope probing indicated only marginal assimilation of polystyrene- 13C by C. coffeae in liquid cultures. NMR spectroscopic analysis of residual styrene contents prior to and after incubation revealed negligible changes in concentration. Thus, this study suggests a plastiphilic life style of C. coffeae despite minor usage of plastic as a carbon source and the general capability of sooty mold fungi to stimulate polystyrene mineralization, and proposes new standards to identify and unambiguously demonstrate plastic degrading capabilities of microbes.

AB - Plastic materials provide numerous benefits. However, properties such as durability and resistance to degradation that make plastic attractive for variable applications likewise foster accumulation in the environment. Fragmentation of plastics leads to the formation of potentially hazardous microplastic, of which a considerable amount derives from polystyrene. Here, we investigated the biodegradation of polystyrene by the tropical sooty mold fungus Capnodium coffeae in different experimental setups. Growth of C. coffeae was stimulated significantly when cultured in presence of plastic polymers rather than in its absence. Stable isotope tracing using 13C-enriched polystyrene particles combined with cavity ring-down spectroscopy showed that the fungus mineralized polystyrene traces. However, phospholipid fatty acid stable isotope probing indicated only marginal assimilation of polystyrene- 13C by C. coffeae in liquid cultures. NMR spectroscopic analysis of residual styrene contents prior to and after incubation revealed negligible changes in concentration. Thus, this study suggests a plastiphilic life style of C. coffeae despite minor usage of plastic as a carbon source and the general capability of sooty mold fungi to stimulate polystyrene mineralization, and proposes new standards to identify and unambiguously demonstrate plastic degrading capabilities of microbes.

KW - C-labeled polystyrene

KW - Cavity ring-down spectroscopy

KW - Phospholipid fatty acid stable isotope probing

KW - Plastic biodegradation

UR - http://www.scopus.com/inward/record.url?scp=85181677024&partnerID=8YFLogxK

U2 - 10.1016/j.chemosphere.2023.141025

DO - 10.1016/j.chemosphere.2023.141025

M3 - Article

VL - 349

JO - Chemosphere

JF - Chemosphere

SN - 0045-6535

M1 - 141025

ER -