Degradation of Bioplastics in Soil and Their Degradation Effects on Environmental Microorganisms

Abstract

Degradation of three kinds of bioplastics and their effects on microbial biomass and microbial diversity in soil environment were analyzed. The degradation rate of bioplastic in soil was closely related to the main components in the bioplastics. Poly (butylene succinate)-starch (PBS-starch) and poly (butylene succinate) (PBS) were degraded by 1% to 7% after 28 days in a soil with an initial bacterial biomass of 1.4 × 10 9 cells/g-soil, however poly lactic acid (PLA) was not degraded in the soil after 28 days. When the powdered-bioplastics were examined for the degradation in the soil, PBS-starch also showed the highest degradability (24.4% degradation after 28 days), and the similar results were obtained in the case of long-term degradation experiment (2 years). To investigate the effect of bacterial biomass in soil on biodegradability of bioplastics, PBS-starch was buried in three kinds of soils differing in bacterial biomass (7.5 × 10 6 , 7.5 × 10 7 , and 7.5 × 10 8 cells/gsoil). The rate of bioplastic degradation was enhanced accompanied with an increase of the bacterial biomass in soil. 16S rDNA PCR-DGGE analysis indicated that the bacterial diversity in the soil was not affected by the degradation of bioplastics. Moreover, the degradation of bioplastic did not affect the nitrogen circulation activity in the soil.

Effect of the Joncryl® ADR Compatibilizing Agent in Blends of Poly(butylene adipate‐co‐terephthalate)/Poly(lactic acid)

“…The large use of plastics in the packaging industry in recent years has increased the interest in polymers with biodegradable and compostable characteristics to replace conventional polymers in order to reduce the impact caused by the inappropriate disposal of these materials in the environment . One of the biodegradable and compostable polymers that has commercial potential use is the poly(butylene adipate co‐terephthalate), PBAT, an aliphatic aromatic copolyester manufactured from petroleum based resources.…”

Sustainability of bioplastics: Opportunities and challenges

“…Chiellini and Corti studied that bio-degradation rate sharply increased after adding the polycaprolactone (biodegradable ester) into the lignin [47]. At last, size and shape of the polymer also affect the rate of the biodegradation [10,36,38,45,48]. If the size of the polymer is larger, biodegradability becomes very slow.…”

Biodegradability of Cassava Edible Bioplastics in Landfill Soil and Plantation Soil

“…These microorganisms used organic carbon as an energy source. In aerobic condition, the organic material, such as bioplastics, would be bio-degraded into CO 2 , H 2 O, and produce heat (Adhikari et al 2016). The carbon dioxide released is fluctuated time by time and shown in Figure 5 for landfill soil and Figure 6 for plantation soil.…”