Biodegradation of Plastics in Tenebrio Genus (Mealworms)
Most petroleum-based plastics are resistant to biodegradation in the environment. Observation of damage, penetration, and ingestion of plastics by insects and their larvae lead to research on biodegradation of plastics by insects. The larvae of darkling b
- PDF / 1,718,403 Bytes
- 38 Pages / 439.37 x 666.142 pts Page_size
- 89 Downloads / 299 Views
Contents 1 Introduction 1.1 Major Plastic Wastes in Environment 1.2 Biodegradation of Plastics by Microorganisms 1.3 Plastic Damaging/Degradation by Insects 2 Biodegradation of Polystyrene (PS) and Polyethylene (PE) 2.1 Polystyrene Degradation 2.2 Polyethylene (PE) Degradation 2.3 Tenebrio Genus in Darkling Beetles 3 Characterization of Plastic Biodegradation 3.1 Survival Rate and PS Consumption 3.2 Factors Influencing Plastic Consumption by T. molitor Larvae 3.3 Reproduction of T. molitor Fed with PS 3.4 PS Degradation by Tenebrio obscurus Larvae 4 Methods for Evaluation of Plastic Biodegradation 4.1 Residual Polymers in Frass 4.2 Major Analytical Methods 4.3 Stable Isotopic Tracer 5 Plastic-Degrading Microbial Communities and Functional Bacteria 5.1 The Role of Gut Microbes in Plastic Degradation 5.2 Plastic-Degrading Microbial Communities 5.3 Plastic-Degrading Gut Microbes 6 Mechanism on Biodegradation of Plastics in Insects and Research Prospects References
S.-S. Yang (*) State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, China e-mail: [email protected] W.-M. Wu Department of Civil and Environmental Engineering, William and Cloy Codiga Resource Recovery, Stanford, CA, USA Center for Sustainable Development and Global Competitiveness, Stanford University, Stanford, CA, USA e-mail: [email protected] Defu He and Yongming Luo (eds.), Microplastics in Terrestrial Environments - Emerging Contaminants and Major Challenges, Hdb Env Chem, DOI 10.1007/698_2020_457, © Springer Nature Switzerland AG 2020
S.-S. Yang and W.-M. Wu
Abstract Most petroleum-based plastics are resistant to biodegradation in the environment. Observation of damage, penetration, and ingestion of plastics by insects and their larvae lead to research on biodegradation of plastics by insects. The larvae of darkling beetles (Coleoptera: Tenebrionidae), especially Tenebrio molitor and Tenebrio obscurus larvae, showed the capacity of rapid gut microbedependent degradation of polystyrene (PS). T. molitor larvae also degrade low-density polyethylene (LDPE). The biodegradation was evaluated on the basis of plastic mass balance, modification of ingested polymers, formation of biodegraded intermediates, as well as 13C isotopic tracer tests. Ingested PS or LDPE polymer can be depolymerized by up 60–70% within 12–24 h after 1- or 2-week adaption. Ingested PS or PE supports the larvae with energy for life activities but not growth. Co-feeding normal diet (e.g., bran) enhances PS and PE consumption rate significantly. Gut microbial communities shifted after the larvae were fed with PS or PE. A few plastic-degrading gut bacterial strains have been isolated from gut of T. molitor, but they grow on plastics slowly. The rapid biodegradation of PS and PE is likely a result of synergistic effects of intestinal microbial activities and host digestive system, and further research is needed to understand the mechanisms. Keywords Biodegradation, Mealworms, Microbial community, Plastics, Teneb
Data Loading...
