Optimization of β-carotene production by a newly isolated Serratia marcescens strain

β-carotene is a commonly used food colorant. in this work, a novel β-carotene producing strain, serratia marcescens rb3, was isolated and identified by physiological and biochemical tests, as well as 16s rdna sequence analysis. the production of β-carotene by s. marcescens rb3 was identified through hplc analysis. the cultivation conditions for β-carotene production by s. marcescens rb3 were optimized as 2.0% lactose, 2.0% peptone, 0.3% beef extract, 1.0% nacl supplemented with 0.05% fe2+, ph 6.0 and 30oc. under the optimal conditions, the yield of β-carotene achieved 2.45 μg/ml.