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Identification of bacterial endospores and targeted detection of foodborne viruses in industrially reared insects for food

Nature Food volume 1, pages 511–516 (2020)Cite this article

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Abstract

With edible insects being increasingly produced, food safety authorities have called for the determination of microbiological challenges posed to human health. Here, we find that the bacterial endospore fraction in industrially reared mealworm and cricket samples is largely comprised of Bacillus cereus group members that can pose insect or human health risks. Hepatitis A virus, hepatitis E virus and norovirus genogroup II were not detected in the sample collection, indicating a low food safety risk from these viral pathogens.

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Fig. 1: Microbial counts of samples assessed for bacterial endospores.
Fig. 2: Identification and characterization of bacterial endospore isolates.

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Data availability

Sequencing data obtained in this study have been deposited in GenBank (National Center for Biotechnology Information) with the accession codes MN508485 to MN508527 (Supplementary Table 1). All other data that support the findings of this study are available from the corresponding author upon request.

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Acknowledgements

Virus references and IACs were provided by I. Di Bartolo from the Italian Istituto Superiore di Sanità (ISS) and N. Cook from Fera Science Ltd. We thank A. Paeleman (Scientia Terrae Research Institute) for her expertise and assistance in designing and optimizing the qPCR protocols, S. Crauwels (KU Leuven) for processing the sequencing results and R. Smets (KU Leuven) for help with the statistics. J. Franciotti, L. De Vrindt, N. Huybrechts, M. Gerits, S. Machtajiw, J. Plas and E. Van Vossole are acknowledged for their assistance in the lab. This research was financially supported by Flanders Innovation & Entrepreneurship (VLAIO) (Project 141129) as well as Internal Funds KU Leuven (grant number PDM/18/159).

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Authors and Affiliations

  1. Lab4Food, Department of Microbial and Molecular Systems (M²S), KU Leuven, Geel, Belgium

    Dries Vandeweyer & Leen Van Campenhout

  2. Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department of Microbial and Molecular Systems (M²S), KU Leuven, Leuven, Belgium

    Bart Lievens

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  1. Dries Vandeweyer
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Contributions

D.V. designed, prepared and executed all experiments, including sample collection and preparation, microbiological analyses, DNA and RNA extractions and PCR and RT-qPCR reactions, and analysed the data, constructed tables and figures and wrote the main text. B.L. and L.V.C. supervised the study, provided additional insight in data analysis and revised the manuscript.

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Correspondence to Leen Van Campenhout.

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Supplementary information

Reporting Summary

Supplementary Table 1

Identification of isolated spore-forming bacteria harboured by yellow mealworms or house crickets.

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Vandeweyer, D., Lievens, B. & Van Campenhout, L. Identification of bacterial endospores and targeted detection of foodborne viruses in industrially reared insects for food. Nat Food 1, 511–516 (2020). https://doi.org/10.1038/s43016-020-0120-z

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