Isolation and Distribution of a Variety of Halophilic Bacteria and Their Classification by Salt-Response

Abstract

A variety of halophilic bacteria were isolated from various saline materials of different salt concentrations. Enriched cultures were used with 4 M NaCI Sehgal and Gibbons complex medium conventionally applied for cultivation of extremely halophilic bacteria. The isolates were classified into nine types from halotolerant to extremely halophilic, based on the salt-response pattern of growth. Among 168 isolates, 75 isolates belonged to type III-A that was moderately halophilic and grew well in added NaCI but not with KCl. This type of bacteria was distributed widely in salted fish, dried fish, salt farm samples, crude salt for soy-sauce making, soy-sauce mashes, seasands and seaweeds. Very high bacterial rates were found in the first three materials. When two enrichment culture media containing 4 M Naci and 4 M KCL were used in parallel, isolates of different salt-response types were obtained from the same material. No isolate requiring KCl specifically was found, even with 4 M KCL medium. © 1980, Japan Society for Bioscience, Biotechnology, and Agrochemistry. All rights reserved.