In the ongoing battle against foodborne pathogens, a team of researchers has uncovered a promising ally in an unlikely place: the humble stingless bee. Tsania Taskia Nabila, a researcher from the Study Program of Biotechnology at Universitas Gadjah Mada (UGM) and the Food Microbiology Research Group at the National Research and Innovation Agency (BRIN) in Indonesia, led a study that explored the antibacterial potential of Bacillus velezensis BP1, a bacterium isolated from stingless bee bread. The findings, published in the Journal of Food Protection (Jurnal Perlindungan Pangan), offer intriguing insights into the development of natural food preservatives and could have significant implications for the food industry.
The research team employed a multi-faceted approach, combining metabolomic and genomic techniques with the one strain-many compounds (OSMAC) strategy. This allowed them to analyze a diverse range of antibacterial compounds produced by Bacillus velezensis BP1 under various conditions. “By using different culture media, we were able to stimulate the bacterium to produce a wide array of compounds,” Nabila explained. “This approach helped us identify the most effective antibacterial agents.”
The study screened twelve extracts from the bacterium, grown in different media, against two notorious foodborne pathogens: Staphylococcus aureus and Salmonella enterica Typhimurium. The results were promising, with two extracts—one from the supernatant of Tryptic Soy Broth with Chitosan (TSB-Chi) and another from the pellet of Tryptic Soy Broth (TSB)—demonstrating significant antibacterial effects. These extracts showed inhibitory concentration (IC50) values of 253.5 ppm and 740.28 ppm, respectively, indicating their potential as effective natural preservatives.
To understand the chemical basis of these antibacterial effects, the team employed Fourier transform infrared spectroscopy (FTIR) and untargeted liquid chromatography-high resolution mass spectrometry (LC-HRMS). These analyses revealed that an amide I group and six specific compounds played crucial roles in the extracts’ antibacterial activity. Furthermore, enrichment analysis suggested that chitosan, a component of one of the culture media, was associated with key metabolic processes in the bacterium.
The researchers also delved into the genetic makeup of Bacillus velezensis BP1, confirming its identity through average nucleotide identity (ANI) analysis and uncovering twelve biosynthetic gene clusters. Six of these clusters were identical to known clusters, while the others showed potential for novel compound production. Molecular docking studies further highlighted the strong binding affinities of certain compounds derived from the bacterium’s genome and metabolites, outperforming the common antibiotic ampicillin in targeting pathogen-associated proteins.
The implications of this research are far-reaching. As the food industry seeks to reduce its reliance on synthetic preservatives, natural alternatives like those identified in this study could play a pivotal role. Moreover, the OSMAC approach demonstrated in this work could be applied to other microorganisms, potentially uncovering a treasure trove of antibacterial compounds. “This study opens up new avenues for exploring the antibacterial potential of microorganisms,” Nabila noted. “It’s an exciting time for the field, with many possibilities for innovation.”
The findings published in the Journal of Food Protection underscore the importance of interdisciplinary research in addressing food safety challenges. As the global population continues to grow, ensuring the safety and quality of our food supply will be paramount. This research offers a glimpse into the future of food preservation, where natural, effective, and sustainable solutions could become the norm. The commercial impacts for the food industry are significant, with potential reductions in food waste, improved shelf life, and enhanced consumer trust in natural products. As the research community continues to build on these findings, the future of food preservation looks increasingly bright.