Gut Microbiome Associating with Carbon and Nitrogen Metabolism during Biodegradation of Polyethene in Tenebrio larvae with Crop Residues as Co-Diets

Abstract

Tenebrio molitor and Tenebrio obscurus (Coleoptera: Tenebrionidae) larvae are two commercial insects that eat plant and crop residues as diets and also biodegrade synthetic plastics polyethylene (PE). We examined biodegradation of low-density PE (LDPE) foam (M n = 28.9 kDa and M w = 342.0 kDa) with and without respective co-diets, i.e., wheat brain (WB) or corn flour (CF), corn straw (CS), and rice straw (RS) at 4:1 (w/w), and their gut microbiome and genetic metabolic functional groups at 27.0 ± 0.5 °C after 28 days of incubation. The presence of co-diets enhanced LDPE consumption in both larvae and broad-depolymerized the ingested LDPE. The diet type shaped gut microbial diversity, potential pathways, and metabolic functions. The sequence of effectiveness of co-diets was WB or CF > CS > RS for larval development and LDPE degradation. Co-occurrence networks indicated that the larvae co-fed with LDPE displayed more complex correlations of gut microbiome than the larvae fed with single diets. The primary diet of WB or CF and crop residues CS and RS provided energy and nitrogen source to significantly enhance LDPE biodegradation with synergistic activities of the gut microbiota. For the larvae fed LDPE and LDPE plus co-diets, nitrogen fixation function was stimulated compared to normal diets and associated with LDPE biodegradation.

Molecular-Weight-Dependent Degradation of Plastics: Deciphering Host–Microbiome Synergy Biodegradation of High-Purity Polypropylene Microplastics by Mealworms

“…Recently, evidence for nitrogen fixation has been found during the degradation of PS, LDPE, and PET by T. molitor larvae. ,, …”

“…70 Recently, evidence for nitrogen fixation has been found during the degradation of PS, LDPE, and PET by T. molitor larvae. 38,56,71 The analysis of gut microbial communities showed that various microorganisms in T. molitor larvae degrade polymers with different MW of PP polymers, yet the main functions of intestinal microorganisms in the process of plastic degradation are unified. This finding implies that the intestinal microbial community of T. molitor larvae contributes to PP biodegradation by forming a system conducive to plastic degradation domesticated through ingesting polymers.…”

Biogas production potential from animal farm waste in Bangladesh: Case studies of two selected farms

“…Solid oxide fuel cells can also be used to generate electricity, and this electricity can be sold at a good price 52 . Additionally, the by‐product of farm waste can be used to improve the soil conditions 53–56 . But, careful consideratons need to be given to heavy metals found in waste 57,58 …”

“…52 Additionally, the by-product of farm waste can be used to improve the soil conditions. [53][54][55][56] But, careful consideratons need to be given to heavy metals found in waste. 57,58…”

Growth Optimization and Rearing of Mealworm (Tenebrio molitor L.) as a Sustainable Food Source

“…They are made commercially for use as pet food for birds and reptiles and fishing bait [9]. As a result of their high nutritious value and low contamination levels, mealworm larvae are a particularly sustainable source of feed and food [10,11]. Exudates, feces, body parts, and dead insects contaminate plant products [12,13].…”