Vitamin B12-producing bacteria as a nutritive complement for a culture of the rotifer Brachionus plicatilis

摘要: Out of 31 bacterial strains isolated from culture tanks the rotifer Brachionus plicatilis, only 8 which were vitamin B12 producers supported growth germ-free when they added into yeast suspension. Of 6 taxonomically examined, identified as Pseudomonas. Their productivity was measured by Euglena bioassay method. The concentrations in suspension daily and higbest levels estimated to be 1.2-16.5ng/ml during day culture. Most (98.1-99.3%) produced accumulated inside cells. growths tested batch cultures under condition, provided with B12-producing bacteria sole food source, these a complement Nannochloropsis oculata or baker's Saccharompces cerevisiae. showed rapid producing cells supplied range 107-1011cells/ml. results imply that mass production tank might play an important role supplier.