Biodegradation of synthetic polymers in soils: Tracking carbon into CO ₂ and microbial biomass

Abstract

Stable isotope labeling of agricultural polyesters enables demonstration of their microbial utilization in soils.

Biodegradable Polymers: Present Opportunities and Challenges in Providing a Microplastic‐Free Environment

“…Laboratory experiments with 13 C‐labeled aliphatic‐aromatic polyester PBAT showed 10% carbon mineralization in about 6 weeks in agricultural soil with biodegradation of each repeat unit from the agricultural center at Limburgerhof (Rhineland‐Palatinate, Germany) ( Figure ). [ 12 ] Although the experiments were not followed till complete degradation, the results regarding the biodegradability of PBAT are highly encouraging with a perspective to replacing polyolefins with such polymers for applications in soil. Promising biodegradation results in agricultural soil were also obtained for PBAT blends with PLA and starch.…”

“…Reproduced with permission under the terms of the CC‐BY‐NC 4.0 License. [ 12 ] Copyright 2018, the Authors. Published by the American Association for the Advancement of Science.…”

“…Current academic literature calls a polymer soil biodegradable if there is any proof of assimilation of its organic C to CO 2 in soil, even though the time of complete assimilation is not known. [ 12 ] This is a common notion. If the time of complete assimilation is very long (persisting in the environment for several years), then a question mark can be added to the utility of such biodegradable polymers in solving the issue of MPs.…”

Microbial degradation of plastic in aqueous solutions demonstrated by CO2 evolution and quantification

“…Thus, the produced CO2 can be directly linked to the mineralisation of the supplied carbon source via bacterial respiration. To confirm the validity of the assay, growth of the soil bacterium R. rhodochrous was carried out on 13 C-glucose 38 . The data (Fig 1b) show that the concentration of CO2 after 196 hours was consistent with that produced as 13 CO2, confirming the suitability of our methodology (p=0.98).…”

Unique properties of Ecoflex® electrospun structures

“…One of those materials is poly(butylene adipate-co-terephthalate) (PBAT) which is a commercially available material known as Ecoflex®, from BASF. This polymer blend is widely used in agriculture due to its short degradation rate which is 6 weeks in soil but also flexibility which makes it a perfect material for mulch films which are of great importance in agriculture production as indicated by the annual market demand in the amount of 2 × 10 6 tones [1]. Another feature that allows the wide use of this material is its biosorbality in human body which, together with its fast biodegradability, allows it to be used in the form of a modern drug carrier system [2].…”