Microplastics measure between 1 micrometre (µm) and 5 millimetres (mm) and are often smaller than a grain of rice. Nanoplastics are even smaller (1–1,000 nanometres), which makes them invisible to the naked eye. Both micro- and nanoplastics are persistent, highly mobile and difficult to remove from the environment, with increasing amounts found in the sea, soil and air. Because of their size, they are difficult to detect and measure.

Micro- and nanoplastics present in the environment can enter the food chain, including drinking water. Microplastics have been detected in various foods, such as mussels, meat, honey, vegetables, beer and table salt.

Some studies suggest that plastic particles may enter human or animal cells, and research has shown that they can also carry contaminants. Once in the environment, microplastics do not biodegrade easily and can persist for long periods. They can accumulate in animals, including fish and shellfish, and may therefore also be consumed by humans through food.

Recently a research done by National Research Council of Science & Technology, A kimchi-derived bacterium can bind to nanoplastics under gut-like conditions and may help carry them out of the body. In mice, the probiotic more than doubled the amount of nanoplastics detected in feces, pointing to a surprising potential use for microbes from fermented foods.

The World Institute of Kimchi (President: Hae Choon Chang), a government-funded research institute under the Ministry of Science and ICT, announced that a lactic acid bacterium isolated from kimchi can help promote the removal of nanoplastics from the body by binding to them in the intestine. 

A research team led by Drs. Se Hee Lee and Tae Woong Whon at WiKim investigated the adsorption capacity of a kimchi-derived lactic acid bacterium, Leuconostoc mesenteroides CBA3656, against polystyrene nanoplastics (PS-NPs).

Under standard laboratory conditions, strain CBA3656 showed a high adsorption efficiency of 87%, comparable to that of the reference strain Latilactobacillus sakei CBA3608 (85%). 

Significant findings were also observed in animal experiments using a germ-free mouse model. Compared with the control group that did not receive probiotics, both male and female mice administered strain CBA3656 showed more than a twofold increase in nanoplastics detected in feces. This result suggests that the probiotic may contribute to the excretion of nanoplastics by binding to them in the intestine.

This study provides scientific evidence that kimchi-derived lactic acid bacteria may interact with environmental micropollutants beyond their traditional role in fermentation. The findings provide new insight into potential biological mechanisms that may help reduce nanoplastic accumulation in the gastrointestinal tract.

“Our findings suggest that microorganisms derived from traditional fermented foods could represent a new biological approach to address this emerging challenge."

Probiotic strains found in Kimichi have shown to have these beneficial effects, such as Lactobacillus Sakei.