title: Efficient cyclic system to yield ectoine using Brevibacterium sp. JCM 6894 subjected to osmotic downshock.
abstract: Brevibacterium sp. JCM 6894 cells grown in the presence of 1.5-2.5 M NaCl for 24 h at 30 degrees C were subjected to the osmotic downshock. Downshocked cells after ectoine release were grown for further 24 h in the fresh medium with same salinity as before shock. When this cyclic system was applied to the strain JCM 6894, the amount of ectoine in the cells increased with an increase of incubation time, which indicates that the cells manipulated by the present conditions were enough active to survive and synthesize ectoine after several times of osmotic downshock. In the presence of 2 M NaCl, the highest yield of ectoine released was achieved in this cyclic system, more than 2.4 g/L during 7 days of incubation. (1)H and (13)C-NMR analyses of solutes released from the cells by the osmotic downshock showed the presence of only ectoine with high purity. Release of ectoine from the cells was carried out within 5 min and its rates were increased by the dilution in the downshock treatment. For the convenience of operations, non-sterilized medium containing 2 M NaCl was examined for the cell growth in the present system, in which almost same level of ectoine yield, release rates, and cell viability were observed as those of sterilized medium.
authors: Environmental Biochemistry Division, Research Center for Inland Seas, Kobe University, Hyogo 658-0022, Japan. nagata@maritime.kobe-u.ac.jp
authors: Shinichi
authors: S
authors: Nagata
authors: Yaoqiang
authors: Y
authors: Wang
authors: Akinobu
authors: A
authors: Oshima
authors: Linghua
authors: L
authors: Zhang
authors: Hideyoshi
authors: H
authors: Miyake
authors: Hideaki
authors: H
authors: Sasaki
authors: Akio
authors: A
authors: Ishida
mesh_terms: D000599:Amino Acids, Diamino / Q000378:metabolism*; D001951:Brevibacterium / Q000187:drug effects / Q000502:physiology*; D018929:Cell Culture Techniques / Q000379:methods*; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D009997:Osmotic Pressure / Q000187:drug effects; D012965:Sodium Chloride / Q000494:pharmacology*
chemical_list: D000599:Amino Acids, Diamino; D012965:Sodium Chloride; C045628:ectoine