Effects of consuming fermented fish (Surströmming) on the fecal microflora in healthy individuals. The effect of Swedish fermented fish on the microbiome

The initial study followed 19 (11 male, 8 female) individuals, recruited from an academic institution in Sweden, over a single period. They ranged in age from 20 to 80. Participnats submitted a baseline sample, attended a party where they consumed Surströmming, a Swedish fermented fish, and provided several follow up samples. Additionally, the Surströmming microbiome was sampled. Samples were sequenced using 16s rRNA sequencing targeting the V34 hypervariable region (341F-805R) primers using a 2x300 kit on an Illumina MiSeq. The follow up focused on a man in his 70s who consumed Surströmming as part of a restricted diet over the course of a week. Samples were sequenced using a 2x150 paired end approach on a BGI DNBseq. Human removal was performed using kraken2 filtering against the Genome Reference Consortium human build 38 reference.