Characterization and antimicrobial potential of bacteriocin-producing lactic acid bacteria isolated from the gut of Blattella germanica

作者：Yuqi Wei, Fangmin Chen, Wanting Xia, Jinyue Song, Jinyan Liang, Xinyao Yang · 发表于：Microbiology Spectrum · 年份：2025 · DOI：10.1128/spectrum.01203-25 · 被引用次数：5 · 研究领域：Insect Utilization and Effects、Insects and Parasite Interactions、Insect symbiosis and bacterial influences

ABSTRACT The gut microbiota of insects plays a crucial role in host nutrition, immune regulation, and disease resistance. As a globally distributed pest, Blattella germanica has adapted to diverse environments and maintains a highly varied diet, making its gut microbiota a largely untapped reservoir of antimicrobial compounds. This study systematically investigated the culturable gut microbiota of Blattella germanica , leading to the isolation of 30 bacterial strains. Morphological characterization and 16S rRNA gene sequence analysis classified these strains into two phyla and eight genera. Among them, six lactic acid bacteria strains were found to produce bacteriocins. Notably, strain X24 exhibited the strongest antibacterial activity, particularly against Escherichia coli . The ethyl acetate-based extraction increased its activity by 39.50%, yielding a concentration of approximately 612.74 µg/mL. Bacteriocin X24 demonstrated a broad antimicrobial spectrum, encompassing both Gram-positive and Gram-negative bacteria as well as fungi. It showed the strongest activity against Escherichia coli (MIC = 37.5 µg/mL), moderate activity against Staphylococcus aureus and Bacillus subtilis (MIC = 75 µg/mL), and relatively weak activity against Pseudomonas aeruginosa , both standard and antibiotic-resistant Salmonella typhimurium , Serratia marcescens , and Enterococcus faecalis (MIC = 150 µg/mL) and Saccharomyces cerevisiae (MIC = 300 µg/mL). The bacteriocin demonstrated good thermostab...