Gut microbial comminoty in Tenebrio molitor larvae responsed to PS and PE within 6 hours

Abstract

Gut microbes of Tenebrio molitor larvae are crucial in plastic degradation. However, microbial responses to the plastic feeding remains unclear. This study aimed to analyze the changes of microbial community and function feeding PE and PS. It found that after 72 h, the larvae survival rate was 92.2% and 82.2% and the plastic weight loss (consumption rate) was 8.8% (0.44 g, p < 0.01) and 6.9% (0.09 g) for PS and PE, respectively. More interestingly, plastic structure changes and the relative microbial responses happened after 6 h. CO and C–O stretching, hydrogen bonding, and a significant decrease in [Mn] (p < 0.05) and [MW] (p < 0.001) were found; Furthermore, the time-similar microbial diversity obviously clustered and the composition significantly changed. The dominant phylum were Firmicutes and Proteobacteria. At genus level, the dominant PS-degrading taxa were unclassified Enterobacteriaceae, Acinetobacter and Sediminibacterium, and were unclassified Enterobacteriaceae, Acinetobacter and Delftia in PE samples; Additionally, difference of carbohydrate metabolism was found, and plastic degrading gene S-formyl glutathione hydrolase significantly high-expressed (PS-3500 fold and PE-5 fold); Moreover, PS-degrading pathways, such as styrene, benzoate, ethylbenzene and xylene degradation pathways were identified. Those illustrated the plastic degrading occurred just within 6 h and the plastic chemistry determined its’ degradability.