Duo Zhixian, Li Haohao, Wang Zeyu, Zhang Zhiwei, Yang Zhuonan, Jin Aofei, Zhang Minwei, Zhang Rui, Qin Yanan
College of Smart Agriculture (Research Institute), Xinjiang University, Urumqi 830017, China.
Xinjiang Key Laboratory of Biological Resources and Genetic Engineering, Xinjiang University, Urumqi 830046, China.
Foods. 2025 Aug 4;14(15):2727. doi: 10.3390/foods14152727.
Microbial detoxification, as an environmentally friendly strategy, has been widely applied for benzo[a]pyrene (BaP) degradation. Within this approach, food-derived microbial strains offer unique advantages in safety, specificity, and sustainability for detoxifying food-borne BaP. In this study, we aimed to explore the potential of such strains in BaP degradation. TC-5, a strain that degrades BaP, was isolated from kefir grains. Surprisingly, 12 genes encoding dehydrogenases, synthases, and oxygenases, including , , , , and , which are related to BaP degradation, were up-regulated by 2.01-fold to 4.52-fold in TC-5. Two potential degradation pathways were deduced. In pathway I, dioxygenase, betaine aldehyde dehydrogenase, and beta-ketoacyl-ACP synthase III FabHB 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 presence of the cytochrome P450 enzyme, BaP progressively mediates ring cleavage via the anthracene pathway, eventually forming 3-methyl-5-propylnonane in pathway II. Notably, 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 application in addressing food-borne BaP contamination. Moreover, our findings expand the application possibilities of Xinjiang fermented milk products and add to the available green strategies for BaP degradation in food systems.
微生物解毒作为一种环境友好型策略，已被广泛应用于苯并[a]芘（BaP）的降解。在这种方法中，源自食品的微生物菌株在解毒食源性BaP方面具有安全性、特异性和可持续性等独特优势。在本研究中，我们旨在探索此类菌株在BaP降解方面的潜力。从开菲尔粒中分离出一株降解BaP的菌株TC-5。令人惊讶的是，在TC-5中，12个编码脱氢酶、合成酶和加氧酶的基因，包括与BaP降解相关的 、 、 、 和 ，上调了2.01倍至4.52倍。推导了两条潜在的降解途径。在途径I中，双加氧酶、甜菜碱醛脱氢酶和β-酮脂酰-ACP合成酶III FabHB依次作用于BaP，通过邻苯二甲酸途径形成4H-吡喃-4-酮，2,3-二氢-3,5-二羟基-6-甲基。在细胞色素P450酶存在的情况下，BaP通过蒽途径逐渐介导环裂解，最终在途径II中形成3-甲基-5-丙基壬烷。值得注意的是，TC-5实现了高达63.94%的BaP去除效率，降解效率为32.89%。这些结果表明，TC-5在解决食源性BaP污染方面具有巨大的应用潜力。此外，我们的研究结果扩展了新疆发酵乳制品的应用可能性，并为食品系统中BaP降解的现有绿色策略增添了内容。
