Kimchi is recognized worldwide as the flagship food of Korea. To date, most of the currently available microbiological studies on kimchi deal with Korean manufactures. Moreover, there is a lack of knowledge on the occurrence of eumycetes in kimchi. Given these premises, the present study was aimed at investigating the bacterial and fungal dynamics occurring during the natural fermentation of an artisan non-Korean kimchi manufacture. Lactic acid bacteria were dominant, while Enterobacteriaceae, Pseudomonadaceae, and yeasts progressively decreased during fermentation. Erwinia spp., Pseudomonasveronii, Pseudomonasviridiflava, Rahnellaaquatilis, and Sphingomonas spp. were detected during the first 15 days of fermentation, whereas the last fermentation phase was dominated by Leuconostoc kimchi, together with Weissellasoli. For the mycobiota at the beginning of the fermentation process, Rhizoplaca and Pichia orientalis were the dominant Operational Taxonomic Units (OTUs) in batch 1, whereas in batch 2 Protomyces inundatus prevailed. In the last stage of fermentation, Saccharomyces cerevisiae, Candida sake,Penicillium, and Malassezia were the most abundant taxa in both analyzed batches. The knowledge gained in the present study represents a step forward in the description of the microbial dynamics of kimchi produced outside the region of origin using local ingredients. It will also serve as a starting point for further isolation of kimchi-adapted microorganisms to be assayed as potential starters for the manufacturing of novel vegetable preserves with high quality and functional traits.

Background/Objectives: Due to the rising problem of antimicrobial resistance, there is increasing attention in the scientific community towards alternative approaches to combat Antimicrobial-Resistant (AMR) pathogens that do not involve the use of antibiotics. In this regard, the European Medicines Agency (EMA) and the European Food Safety Authority (EFSA) have promoted experimentation with predatory bacteria to fight antibiotic resistance. With the aim of identifying predatory bacteria suitable for the control of antibiotic-resistant bacteria, in this work we isolated a strain of Halobacteriovorax from an estuarine aquatic environment using a CTX-M-producing E. coli strain as prey and characterized it with respect to optimal physico-chemical parameters for growth and predation. Furthermore, we studied its predatory capacity against other E. coli strains and Multi-Drug-Resistant (MDR) Salmonella. Finally, we conducted challenge experiments to evaluate the growth of predator and prey over time. Methods: The Halobacteriovorax strain, designated HE7, was identified by 16S rRNA analysis. To isolate Halobacteriovorax and to evaluate its predatory ability towards different preys, the double-layer agar plating technique was applied. Results: HE7 showed in vitro predatory activity against all MDR strains of E. coli and Salmonella tested. In the 10⁷ predator/10³ prey and 10⁷ predator/10⁷ prey challenges, HE7 after 6 h achieved the total killing and a reduction of about 6 logs in the prey, respectively, maintaining this effect for up to 24 h. Conclusions: The results of this study highlight that HE7, but more generally Halobacteriovorax, could find application both alone and in an integrated context of antimicrobial strategies as an alternative to antibiotics.

It is known that the consumption of edible lamellibranch mollusks (ELMs), undercooked or raw, is a vehicle for the oral transmission of viral and bacterial pathogens. The ELMs most frequently fished/cultivated and consumed in Italy are Mytilus galloprovincialis and Chamelea gallina. The aim of this project was to standardize the cooking conditions of M. galloprovincialis and C. gallina, reproducible in a domestic environment, to obtain food in which the microbiological risk was eliminated but, at the same time, preserved the original organoleptic characteristics. The results showed that for C. gallina and M. galloprovincialis, cooking for 2 minutes after opening all shells, according to a method suitable for home application, is sufficient to eliminate the microbiological risk.