Eimaan Bilal, Class of 2028

Bacteriocins are activated polypeptides that mostly produce lactic acid group bacteria (LAB) molecules, which have been determined to be safe to use under the Joint Food and Agriculture Organization (FAO). LAB-producing bacteriocin has a wide range of applications in the food industry, ranging from enhancing overall food quality to inhibiting the growth of microorganisms in food packaging. However there is still hesitance to begin using them at a larger scale since only a limited number have been approved for usage in the food industry. Currently, the nisin bacteriocin is the only one deemed safe by the FAO to be used as a food preservative in cheese and meat products. Dr. Qingping Liang and his team aimed to investigate any possible risks associated with bacteriocins and their interactions with the gastrointestinal (GI) tract before they are further implemented into the food industry. 

The research group classified more than 230 types of bacteriocins that were isolated from LAB molecules and categorized them into three groups based on overall structure, molecular weight, and chemical properties. Past testing concluded that bacteriocins did not cause cell-damaging reactions to occur during GI traversal. This is due to most bacteriocins having a small enough molecular weight to traverse the tract, as having too high a weight would make it difficult to be absorbed into the bloodstream. Therefore, the group wanted to determine whether decomposed bacteriocin fragments can still pose a risk if they retain some bioactivity and interfere with other bodily systems as they pass through the GI. After analyzing reports on food industrial LAB bacteriocins, the group discovered that most bacteriocin fragments, after being broken down by digestive enzymes in the GI environment, are more likely to pass across the intestinal wall and enter the bloodstream because of their small size. Ultimately, this may pose a risk to the metabolic function of other bodily systems, since cytotoxicity from smaller LAB bacteriocins can cause damage to vital human tissues and organs. 

Dr. Liang’s research group suggests that one way to combat the risks associated with LAB-producing bacteriocin before being implemented in the food industry is to reorganize the amino acid sequences of the bacteriocin. The team speculates that this would enhance the recognition sites of digestive enzymes when the bacteriocin is broken down in our digestive system, reducing the risk of cytotoxicity. Overall, more research is needed to ensure that LAB-producing bacteriocins can pass through the GI system safely before they are introduced into consumer’s food products. 

Figure 1: The gastrointestinal (GI) tract. The image depicts the small intestine and the large intestine.

Works Cited: 

[1] Liang, Q., Liu, Z., Liang, Z., Fu, X., Li, D., Zhu, C., Kong, Q., & Mou, H. (2024). Current challenges and development strategies of bacteriocins produced by lactic acid bacteria applied in the food industry. Comprehensive Reviews in Food Science and Food Safety, 24(1). https://doi.org/10.1111/1541-4337.70038 

[2] Image retrieved from: https://pixabay.com/illustrations/intestine-biology-science-bowels-4413737/