isolation, identification and physiological characteristics of high carotenoids yield rhodopseudomonas faecalis psb-b

Carotenoid is a natural antioxidant and rich in the photosynthetic bacteria. We described here the isolation of strain PSB-B, which has the ability of high produce with carotenoids, from Fenhe River in China. Based on phenotypic, physiological, biochemical and phylogenetic (16S rDNA) studies, strain PSB-B could be classified as a strain of R. faecalis. The condition of fermentation carotenoids from strain PSB-B was optimized of temperature, inoculum concentration and light intensity 3 aspects by response surface methodology. The results showed that the optimal conditions were 30.88 °C, 2172 lux and 9.66 % inoculum concentration. Under these conditions, the practical yield of carotenoids was 16.93 mg/L.