In the heart of Xinjiang, China, a team of researchers led by Zhixian Duo from the College of Smart Agriculture at Xinjiang University has uncovered a promising solution to a pervasive problem in the food industry: benzo[a]pyrene (BaP) contamination. Their study, published in the journal *Foods* (which translates to “Foods” in English), focuses on a bacterium derived from kefir grains, *Bacillus mojavensis* TC-5, which shows remarkable potential for degrading BaP, a known carcinogen found in food.
BaP is a polycyclic aromatic hydrocarbon that often contaminates food through environmental pollution, smoking, and incomplete combustion. Its presence in food poses significant health risks, necessitating effective and safe detoxification methods. Traditional approaches to BaP degradation often involve chemical or physical processes that can be environmentally harmful. In contrast, microbial detoxification offers a greener, more sustainable alternative.
Duo and his team isolated *Bacillus mojavensis* TC-5 from kefir grains, a fermented milk product popular in Xinjiang. “We were surprised to find that this strain not only degrades BaP but also up-regulates several key genes involved in the process,” Duo explained. The study identified 12 genes encoding enzymes such as dehydrogenases, synthases, and oxygenases, which were up-regulated by 2.01-fold to 4.52-fold in TC-5. These enzymes play crucial roles in BaP degradation, suggesting that the bacterium has a robust mechanism for breaking down the harmful compound.
The researchers deduced two potential degradation pathways. In the first pathway, dioxygenase, betaine aldehyde dehydrogenase, and beta-ketoacyl-ACP synthase III act sequentially on BaP to form 4H-pyran-4-one,2,3-dihydro-3,5-dihydroxy-6-methyl via the phthalic acid pathway. In the second pathway, the cytochrome P450 enzyme mediates ring cleavage via the anthracene pathway, eventually forming 3-methyl-5-propylnonane. “These pathways provide a clear picture of how TC-5 degrades BaP, which is crucial for understanding its potential applications,” Duo noted.
The study found that TC-5 achieved an impressive BaP removal efficiency of up to 63.94%, with a degradation efficiency of 32.89%. These results suggest that TC-5 has significant potential for addressing food-borne BaP contamination. “Our findings not only highlight the potential of TC-5 in food safety but also expand the application possibilities of Xinjiang fermented milk products,” Duo added.
The implications of this research extend beyond the food industry. The energy sector, which often deals with similar contaminants in biofuels and other products, could benefit from the development of microbial detoxification methods. The use of food-derived microbial strains like TC-5 offers a safe, specific, and sustainable approach to detoxifying harmful compounds, reducing the need for more environmentally damaging processes.
As the world continues to seek greener and more efficient solutions to environmental and health challenges, research like Duo’s provides a beacon of hope. By leveraging the power of naturally occurring microorganisms, we can develop innovative strategies that are both effective and sustainable. The study published in *Foods* not only advances our understanding of BaP degradation but also paves the way for future developments in food safety and environmental protection.