A probiotic bacterium found in kimchi may help the body remove harmful nanoplastics by binding to them in the intestine, according to new research from the World Institute of Kimchi in South Korea. The findings highlight a potential biological tool for countering the growing problem of plastic pollution inside the body.
Nanoplastics are ultrafine particles smaller than 1 micrometer that form as larger plastics break down in the environment. They can enter the body through food and drinking water, while their extremely small size allows them to cross intestinal barriers and accumulate in organs including the kidneys and brain.
How a kimchi microbe binds plastics
The research team, led by Drs. Se Hee Lee and Tae Woong Whon, focused on a lactic acid bacterium isolated from kimchi known as Leuconostoc mesenteroides CBA3656. The scientists tested its ability to bind polystyrene nanoplastics, a commonly studied type of plastic particle.
Under standard laboratory conditions, the kimchi-derived strain adsorbed approximately 87% of the nanoplastics it encountered. This was similar to the reference probiotic strain Latilactobacillus sakei CBA3608, which reached 85%, showing that both strains could effectively attach to nanoplastics in a controlled environment.
The researchers then simulated the human intestinal environment to test how the bacteria performed under conditions more closely resembling those inside the body. In this harsher setting, the adsorption rate of the reference strain dropped sharply to just 3%, while the kimchi-derived strain continued to bind approximately 57% of the nanoplastics.
The team concluded that Leuconostoc mesenteroides CBA3656 can maintain strong binding to plastic particles even under gut-like conditions. Such stability would be important if probiotics were eventually to play a practical role in reducing internal exposure to microscopic plastics.
Mouse study points to higher excretion
To investigate whether this binding could produce biological effects, the researchers turned to germ-free mice, which are raised without naturally occurring gut microbes. Some mice received the kimchi-derived probiotic, while a control group received no probiotic treatment.
Both male and female mice given Leuconostoc mesenteroides CBA3656 had more than twice as many nanoplastics in their feces as mice in the control group. The result suggests that the bacteria helped carry nanoplastics out of the body rather than allowing the particles to remain within the intestinal tract.
The researchers interpret the finding as evidence that the probiotic can attach to nanoplastics in the gut and promote their excretion. However, further research will be needed to establish whether the same effect occurs in humans and whether it extends to other types of plastic particles.
Broader implications for health and food
The findings add another dimension to the potential benefits associated with kimchi, the traditional Korean fermented food rich in lactic acid bacteria. Beyond their established roles in fermentation, flavor and preservation, microbes found in kimchi may also interact with environmental contaminants such as microplastics and nanoplastics.
Lead researcher Dr. Se Hee Lee said plastic pollution is increasingly being viewed not only as an environmental crisis but also as a public health concern. The findings suggest that microbes originating from fermented foods could potentially provide a biological approach to reducing exposure to microscopic plastic particles.
The researchers emphasize that the work remains at an early stage. Human trials, safety assessments and studies involving other probiotics and different types of plastic will be necessary before clinical recommendations can be made. Nevertheless, the research opens a potential avenue for investigating whether food-derived microbes could help mitigate emerging pollution risks.
The World Institute of Kimchi plans to expand its research into kimchi microbial resources to better understand how they might support public health and contribute to solutions for environmental challenges. As concerns about plastic contamination continue to grow, biological strategies such as these could eventually complement wider efforts to reduce plastic use and improve waste management.
