16S rDNA sequencing of mixed bacterial samples with different degradation rates of DON

Vomitoxin, also known as deoxynivalenol (DON), is a fungal toxin primarily produced by the genus Fusarium and widely found in contaminated cereals, cereal products, and feeds, posing a serious threat to the edible safety of cereals and their products. Excessive intake of deoxynivalenol can severely jeopardize the health of humans and animals, making the detoxification research of deoxynivalenol a current research hotspot. This study aims to degrade deoxynivalenol using biological methods and detect its concentration through ELISA. By combining microbial 16S rDNA diversity sequencing, we selectively isolated and screened deoxynivalenol-degrading bacteria from the cecal contents of chickens, which are the least sensitive to deoxynivalenol, and conducted in-depth exploration of their characteristics. Apparent identification of the strains was conducted through morphological identification, Gram staining, and molecular biological identification methods, and their probiotic functions were further explored through whole-genome sequencing. We investigated their growth characteristics, stress resistance, and inhibitory effects on pathogenic bacteria. The degradation pathway was determined by measuring the degradation rate of DON by different components of the strains. Finally, in vitro cellular experiments were conducted to explore the effects of co-culture of degradation bacteria and DON on IPEC-J2 cell proliferation, intestinal tight junctions, host defense peptides, and the expression of inflammation-related genes and proteins. This research lays the foundation for the development of efficient, safe, and environmentally friendly microecological preparations for DON detoxification.

呕吐毒素（Vomitoxin），又名脱氧雪腐镰刀菌烯醇（deoxynivalenol，DON），是一类主要由镰孢菌属（Fusarium）产生的真菌毒素，广泛分布于受污染的谷物、谷物制品及饲料中，对谷物及其制品的食用安全构成严重威胁。过量摄入脱氧雪腐镰刀菌烯醇会严重损害人类与动物的机体健康，使得脱氧雪腐镰刀菌烯醇的脱毒研究成为当前的研究热点。本研究拟通过生物法降解脱氧雪腐镰刀菌烯醇，并采用酶联免疫吸附试验（ELISA）检测其浓度。结合微生物16S rDNA多样性测序技术，本研究从对脱氧雪腐镰刀菌烯醇最不敏感的鸡盲肠内容物中，选择性分离筛选出可降解脱氧雪腐镰刀菌烯醇的菌株，并对其生物学特性展开深入探究。通过形态学鉴定、革兰氏染色及分子生物学鉴定手段对菌株进行明确鉴定，并借助全基因组测序进一步解析其益生功能。本研究考察了该菌株的生长特性、抗逆性能及对致病菌的抑制活性。通过测定菌株不同组分对脱氧雪腐镰刀菌烯醇的降解率，明确其降解途径。最终开展体外细胞实验，探究降解菌株与脱氧雪腐镰刀菌烯醇共培养对IPEC-J2细胞增殖、肠道紧密连接、宿主防御肽及炎症相关基因与蛋白表达的影响。本研究为开发高效、安全、环保的脱氧雪腐镰刀菌烯醇脱毒微生态制剂奠定了基础。