Identification of a Blue Pigment Producing Strain and Characterization of Produced Pigment

Purposes: To identify the classification position of a blue pigment producing strain named as B9-8 isolated from low temperature sewage and to characterize pigment produced by it.Methods: Based on morphological observation and 16 S rRNA sequence alignment,the strain was identified as a possible new member of the genus Janthinbacterium.Results: The blue pigment from this strain showed a maximum absorption peak at 579 nm and had good solubility in water and organic solvents.In addition,it was stable to heat and pH but unstable to light.After 3 d of exposure to natural sunlight a loss of 61.3% was found.Low concentrations of metal ions had little effects on its stability,whereas some metal ions at high concentrations,especially Al3+,had a great impact on its stability,resulting in a loss as high as 73.1%.Conclusion: Therefore,we speculated that the blue pigment might be violacein.