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Salted and ripened fish foods are susceptible to cause histamine poisoning. The present study focuses on microbial histamine degradation from high salted fermented fishery products to deepen our understanding about this new and growing field of research. As a result of this first study related to salted-ripened anchovies (Engraulis anchoita), fifty seven moderate and extreme halophilic microbial isolates from salt and salted-ripened anchovy processes were characterized in terms of their phenotype and histamine-degrading capacity. Only 7%-4 isolates-were able to degrade histamine. None of the histaminedegrading isolates presented proteolytic and/or lipolytic activity. One of them designated A18 was chemotactic toward histamine, an interesting property not previously reported for that chemoattractant. However, the S18 and A18 isolates, genotypically identified as Halobacterium sp. and Halomonas sp. respectively, produced indole and/or H 2 S, both undesirable characteristics associated to off-flavors occurrence. On the other hand, A28 and S20, identified as Halovibrio sp. and Halobacterium sp. respectively, presented desirable properties, such as cytochrome oxidase and catalase activity, and nonproduction of H 2 S and indole. These strains also showed characteristics previously reported as dominant in the ripened stage. The results are promising, and A28 and S20 may have the desirable features to improve the anchovy salting-ripening process. KeywordsSalted and ripened anchovy • Halophilic prokaryotes • Phenotypic characterization • Chemotaxis • Histamine • 16S rRNA identification Communicated by A. Oren.

A facultative aerobic, Gram-negative, motile, non-endospore forming and extremely halophilic bacterium, strain 11aii⊺, isolated from salted-ripened anchovy, was examined using a polyphasic approach to characterize and clarify its phylogenetic and taxonomic position. Sequences of the 16S rRNA gene revealed close relationships to species of the genera Lentibacillus and Virgibacillus (94.2% similarity). The organism grew optimally in the presence of 20-35 % NaCl. The major fatty acids of strain 11aii⊺ were C16:0 (42.1%) and anteiso-C15:0 (31.2%) and also presented iso-C16:0 (11.0%), anteiso-C17:0 (10.4%) and C18:0 (5.2%). Based on data presented here, strain 11aii⊺ is considered to represent a novel genus and species, for which the name Haloargentinum marplatensis gen. nov. sp. nov. is proposed with the strain 11aii⊺ as type strain.