Diversity and community composition of strictly anaerobic and culturable bacteria from the feces of Styrofoam-fed Tenebrio molitor larvae: a culturomics-based study

Junyu Zhu; Xiaochen Chen; Sheng-Chung Chen; Wanling Qiu; Jianying Yu; Tengfei Guo; Xianxing Wang

doi:10.3389/fmicb.2023.1309806

Diversity and community composition of strictly anaerobic and culturable bacteria from the feces of Styrofoam-fed Tenebrio molitor larvae: a culturomics-based study

Front Microbiol. 2023 Dec 5:14:1309806. doi: 10.3389/fmicb.2023.1309806. eCollection 2023.

Authors

Junyu Zhu^{1

2}, Xiaochen Chen¹, Sheng-Chung Chen^{1

2}, Wanling Qiu², Jianying Yu^{1

3}, Tengfei Guo^{1

3}, Xianxing Wang^{1

3}

Affiliations

¹ Innovation Center for Soil Remediation and Restoration Technologies, College of Environment and Safety Engineering, Fuzhou University, Fuzhou, Fujian, China.
² School of Resources and Chemical Engineering, Sanming University, Sanming, Fujian, China.
³ The Second Geological Exploration Institute, China Metallurgical Geology Bureau, Fuzhou, Fujian, China.

Abstract

Introduction: In recent years, researchers have been exploring the plastic-degrading abilities of bacteria residing in the guts of Styrofoam-eating Tenebrio molitor larvae. However, none of the reported strains have displayed highly efficient plastic degradation capabilities, and it's noteworthy that none of the existing studies have focused on strictly anaerobic microbes.

Methods: In this study, we exclusively fed Styrofoam to T. molitor larvae and examined how this dietary change influence the gut's bacterial community composition, as observed through fecal bacteria using bacterial 16S rRNA gene amplicon sequencing and the small-scale culturomics method with 20 types of anaerobic media under four different conditions.

Results: The results revealed a significant shift in the dominant phylogroup from Lactococcus (37.8%) to Escherichia-Shigella (54.7%) when comparing the feces of larvae fed with bran and Styrofoam, as analyzing through the bacterial 16S rRNA gene amplicon sequencing. For small-scale culturomics method, a total of 226 strains of anaerobic bacteria were isolated and purified using the rolling-tube/strictly anaerobic technique. Among them, 226 strains were classified into 3 phyla, 7 classes, 9 orders, 17 families, 29 genera, 42 known species and 34 potential novel species.

Discussion: Interestingly, 24 genera in total, identified through the culturomics method, were not found in the results obtained from amplicon sequencing. Here, we present a collection of culturable anaerobic bacteria from the feces of T. molitor larvae, which might be a promising avenue for investigating the biodegradability of plastics by combining specific strains, either randomly or intentionally, while considering the abundance ratio of the microbial community composition.

Keywords: Styrofoam; Tenebrio molitor; anaerobic bacteria; bacterial diversity; feces; gut microbiome; polystyrene.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This study was financially supported by the National Natural Science Foundation of China (41807116; 42377380), the Natural Science Foundation of Fujian Province of China (2023J01418; 2022N0024), the Scientific and Technological Innovation Project of China Metallurgical Geology Bureau (CMGBKY202301), the Independent Innovation Foundation of Tianjin University and Fuzhou University (TF2023-3), the Fuzhou University Testing Fund of Precious Apparatus (2023T014), the grants from the 2022/2023 Annual University Students’ Innovation and Entrepreneurship Training Program Project (CA220255/202311311022), and Fujian Sanming University Introduced High-Level Talents Research Start-Up Funding Project (20YG09).