Biosurfactant production by a Bacillus megaterium strain.

The aim of the present study was to investigate the ability of Bacillus megaterium IBB(Po17) (GenBank KX499518) cells to produce biosurfactant when the growth was done in the presence of long-chain n-alkane n-hexadecane on medium supplemented with yeast extract, proteose peptone, starch, or cellulose. B. megaterium IBB(Po17) revealed a higher growth in the presence of n-hexadecane when the medium was supplemented with yeast extract, proteose peptone, or starch, compared with cellulose. Biosurfactant production was higher when B. megaterium IBB(Po17) was grown in the presence of n-hexadecane on yeast extract, proteose peptone, or starch supplemented medium, compared with biosurfactant produced on cellulose supplemented medium. A direct correlation between cell growth and biosurfactant production was observed. When the growth of B. megaterium IBB(Po17) cells was higher, the decrease in pH values of the medium was higher too, and more amount of CO(2) was released. Changes in cell morphology, aggregation of the cells in clusters, and biofilm formation were observed when B. megaterium IBB(Po17) was grown in the presence of n-hexadecane on medium supplemented with yeast extract, proteose peptone, starch, or cellulose. Due to its physiological abilities, this Gram-positive bacterium could be a promising candidate for the bioremediation of petroleum hydrocarbon polluted environments.