传统咸干鲅鱼自然风干过程细菌菌群变化

Change of bacterial flora during natural air drying of traditional dried salted mackerel

目的揭示咸干鲅鱼自然风干过程中细菌菌落结构的变化规律。方法采用高通量测序技术对新鲜鲅鱼以及风干2、4、6、8、12d的鲅鱼样品中的细菌种类及其丰度进行分析。结果新鲜鲅鱼中发光杆菌属(Photobacterium)、嗜冷单胞菌属(Psychrobacter)、交替假单胞菌属(Pseudoalteromonas)和黄杆菌属(Flavobacterium)所占比例较高,是新鲜鲅鱼的优势菌;风干过程中,Pseudoalteromonas在风干前期比例增加,4 d后比例逐渐减少;Photobacterium在风干前2 d比例降低,之后比例迅速增加,12 d时比例高达80%,是传统咸干鲅鱼的优势菌属。鲅鱼风干过程微生物种类趋向简单化,菌群功能主要聚焦在化能异养作用、有氧异养作用和发酵,其中化能异养作用、有氧异养作用对应的丰度相对稳定,而发酵对应的丰度在风干后期呈增加趋势。胁迫耐受、兼性厌氧、运动性等表型丰度增加,好氧对应的丰度降低,这与风干后期发酵功能对应的丰度增加的现象一致。结论高通量测序的结果更加全面地揭示了咸干鲅鱼风干过程细菌菌落结构及其丰度的变化规律,这为进一步了解传统水产制品中的未培养微生物、优化加工工艺提供了参考。

Objective To reveal the changing rule of bacterial colony structure of dried salted mackerel during natural air drying.Methods The bacterial species and abundance of fresh sample and samples dried for 2,4,6,8 and 12 d were analyzed using high throughput sequencing technology.Results The fresh mackerel was dominated by the genera Photobacterium,Psychrobacter,Pseudoalteromonas and Flavobacterium,with a high proportion;during the air drying process,the proportion of Pseudoalteromonas increased in the early stage of air drying and gradually decreased after 4 d;the proportion of Photobacterium was decreased 2 d before air drying and then increased rapidly,reaching 80%at 12 d,making it the dominant strain of traditional dried salted mackerel.The microbial species tended to be simplified in the air drying process of mackerel,and the microbial community function was mainly focused on chemical energy heterotrophic effect,aerobic heterotrophic effect and fermentation,and the abundance corresponding to chemical energy heterotrophic effect and aerobic heterotrophic effect was relatively stable,while that corresponding to fermentation showed an increasing trend in the late air drying.The abundance of such phenotypes as stress tolerance,facultative anaerobic and kinesthetic increased,while the abundance corresponding to aerobic decreased,which was consistent with the increase in abundance corresponding to the fermentation function in the later stage of air drying.Conclusion The results of high throughput sequencing reveal more comprehensively the structure of bacterial colonies and their abundance during the air drying process of salted dried mackerel,which provides a reference for further understanding the uncultured microorganisms in traditional aquatic products and optimizing the processing process.