Abstract: For the synthesis of carotenoids bacterium Erwinia uredovora.MgSO4 had the best positive effects among 8 inorganic salts,which can promote the growth of Erwinia uredovora and increase its pigments yield.All of the four carbon sources （glucose,sucrose,maltose and glycerol）could promote the cell biomass and biosynthesize the carotenoids with glucose as the best.As for the 5 nitrogen sources,yeast extract served as the best nitrogen source for the growth and pigments accumulation, followed by peptone and beef extract.Erwinia uredovora could not utilize urea and ammonium nitrate.The carbon and nitrogen cencentrations the culture media are 2.45～4.90g/L and 1.60～2.40g/L respectively,beneficial to both the cell growth and carotenoids production.The optimal C:N ratio is 2.5:1.It showed that the stability of carotenoids the acetone extract of Erwinia uredovora becomes worse and degrades fast during the first 24h under the room temperature.11 pigments are detected from Erwinia uredovora.

Key words: Erwinia uredovora, inorganic salts, carbon and nitrogen sources, carotenoid yield, stability