暗纹东方鲀冷藏期间细菌群落结构与功能变化

Microbial Community Structure and Function Succession of Puffer Fish(Takifugu obscurus)During Refrigeration

目的:探究暗纹东方鲀(Takifugu obscurus)冷藏期间的微生物群落结构与功能变化规律,明确贮藏过程的优势菌属。方法:通过高通量测序技术研究冷藏期间(4℃,8 d)暗纹东方鲀细菌群落结构组成与变化规律,利用Tax4Fun2软件进行细菌群落功能预测,并测定其挥发性盐基氮(Total Volatile Basic-N,TVB-N)、pH、感官评分等指标变化。结果:高通量测序表明贮藏期间样品细菌群落发生显著变化,初期的主要菌属有不动杆菌属(Acinetobacter)、乳杆菌属(Lactobacillus)、气单胞菌属(Aeromonas)、假单胞菌属(Pseudomonas)等,贮藏后期假单胞菌属(Pseudomonas)的相对丰度增至91.7%以上,成为优势菌属。贮藏初期α多样性指数较高,贮藏后期明显降低。细菌群落功能预测结果显示贮藏后期的氨基酸代谢、细胞交流、膜运输等功能通路丰度升高。贮藏后期样品pH、挥发性盐基氮值、菌落总数呈上升趋势,感官评分呈下降趋势。结论:样品贮藏过程中,微生物群落结构与功能发生明显演替,假单胞菌属(Pseudomonas)是贮藏过程中的优势菌属;该结果可为暗纹东方鲀后续相应保鲜技术的开发提供理论指导。

Objective:To reveal the microbial community and its function succession principles of puffer fish(Takifugu obscurus),and to identify the dominant microbial genera on puffer fish during refrigerated storage.Methods:High-throughput sequencing was employed to investigate the microbial composition of puffer fish during refrigeration(4℃,8 d),the community function was predicted by Tax4fun2,and the total volatile basic-nitrogen(TVB-N),pH and organoleptic values of puffer fish were measured as well.Results:The high-throughput sequencing demonstrated that during refrigeration the bacterial community of puffer fish succeed significantly,which were mainly composed of genera Acinetobacter,Lactobacillus,Aeromonas and Pseudomonas at the initial stage,while at the last stage composed almost of genera Pseudomonas(>91.7%),which was considered as the dominant genera on puffer fish.Theα-diversity index of the community was higher at initial stage,while decreased during the storage.The microbial community function prediction results showed that the relative abundance of the amino-acid metabolism pathway and the cellular communication pathway increased at the last stage of the storage.As for the physicochemical properties,TVB-N,pH and total microbial counts increased while sensory scores decreased during the storage.Conclusion:The microbial community and its functional profile changed significantly during refrigeration,Pseudomonas was the dominant genera of puffer fish,and the above conclusion would provide theoretic guidelines for developing novel preserving technology for puffer fish.