Metataxonomic Exploration of Non-Korean Kimchi Made With Sea Fennel (Crithmum maritimum L.)

In this study, a non-Korean kimchi formulated with the unconventional ingredient sea fennel (Crithmum maritimum L.) was investigated under both spontaneous and starter-driven fermentation to assess microbial composition and dynamics. Metataxonomic analyses revealed significant differences between starter-inoculated and control (spontaneously fermented) kimchi. Weissella koreensis and members of the genus Companilactobacillus dominated the control samples, whereas Levilactobacillus spp., Lactiplantibacillus plantarum, and Pediococcus pentosaceus prevailed in the starter-inoculated kimchi. Fungal community profiling consistently showed the dominance of the genus Alternaria throughout fermentation in both prototypes. Kazachstania servazzi became abundant at late fermentation in both kimchi types, while Saccharomyces cerevisiae appeared exclusively in the control samples during mid-fermentation. Isolation of lactic acid bacteria provided further insights into active microbial populations across fermentation stages. W. koreensis and Leuconostoc mesenteroides were the most frequently detected species. The isolates displayed considerable heterogeneity in enzymatic activity profiles: strong leucine arylamidase and β-glucosidase activities were identified, both potentially influencing kimchi's sensory traits. Importantly, no β-glucuronidase activity was detected, suggesting safety of the isolates with respect to cancer-associated risks. Conversely, three isolates carried the hdcA gene, and none exhibited bacteriocin activity against Listeria innocua (used as a surrogate for Listeria monocytogenes). Most isolates demonstrated robust growth and activity in a kimchi-like medium, underscoring their performance as starter or adjunct cultures for guided fermentation of kimchi. PRACTICAL APPLICATIONS: This scientific research used DNA-based microbial profiling to identify high technological lactic acid bacteria that can serve as starter cultures for guided kimchi fermentation. These findings may help producers create safe, more consistent, and high-quality fermented vegetables for global markets.