Effects of Various Phosphates on Biosurfactant Fermentation by Ochrobactrum Intermedium XY-1

Abstract

Phosphates are important components in the fermentation medium for biosurfactant production. In the present study, Ochrobactrum intermedium strain XY-1 was used as the experimental strain, the effects of various phosphates used in the biosurfactants fermentation media was preliminarily investigated on cell growth, and surface tension, and emulsifying activity of fermentation broth. Under the same total phosphorus concentration of 0.035 mol/L, KH2PO4 + Na2HPO4, KH2PO4, and Na2HPO4 was respectively used as the phosphorus source of biosurfactant fermentation at 30 °C and 160 rpm. The results showed that the bacteria grew slowly and the maximum emulsifying activity of fermentation broth reached 52.95% in the fermentation with KH2PO4 + Na2HPO4 as phosphorus source, and larger bacterial growth and 35.9% maximum emulsifying activity exhibited in the fermentation with KH2PO4, smaller bacterial growth and 24.54% maximum emulsifying activity exhibited in the fermentation with Na2HPO4. The phosphate mixture of KH2PO4 and Na2HPO4 benefits the biosurfactant fermentation by limiting the growth of Ochrobactrum intermedium strain XY-1, which might be the earliest report on the phosphorous source of biosurfactant fermentation by Ochrobactrum intermedium.