Investigation of microbial ecology of salted seafood based on culture method and 16S rRNA metagenome sequencing

Abstract

The present study attempted to identify the entire microbial ecology of salted seafood using both a culturedependent method and high-throughput sequencing. Samples (10 types: shrimp, squid, oyster, Alaska pollock roe, cutlassfish intestine, beka squid, croaker, long-arm octopus, flatfish, and damselfish) from two different brands were collected in two seasons (summer and winter) (n = 120). Aerobic plate counts in summer (average 5.87 log CFU/g) were higher than in winter (average 5.05 log CFU/g). Coliforms were not discovered in most samples but were detected in the salted oyster, cutlassfish intestine, and flatfish (below LOQ-2.40 log CFU/g). Lactic acid bacteria were especially abundant in salted flatfish. Salted seafood contains both beneficial and potentially hazardous bacteria. Leuconostocaceae, which showed the largest relative abundance at the family level (34.97%), were especially prominent in salted long-arm octopus (65.35%). Enterobacteriaceae and Staphylococcus, potentially dangerous bacteria, were detected in salted Alaska pollock roe. Diversity analysis demonstrated that raw materials had a substantial impact on the microbial community of salted seafood. This is the first study to use two methods to study a wide variety of salted seafood. By presenting deep understandings of the microbiome of salted seafood, this study provides a foundation for research on fermented seafood.