Gentamicin production by Micromonospora echinospora (Me- 22) in stirred tank reactor: effect of various parameters.

Effect of production medium components, initial starch and soyabean meal concentrations, for the enhanced production of gentamicin by Micromonospora echinospora (Me- 22) was studied in a lab scale stirred tank reactor. Also effect of different aeration (0.5, 1, 2, and 4 vvm) and agitation rates (100, 200, 300 and 400 rpm) in a stirred tank reactor was examined. A maximum gentamicin concentration of 2.68 g l(-1) was achieved in the medium having low concentrations of initial starch (7.5 g l(-1)) and high concentrations of initial soyabean meal (4 g l(-1)). Both aeration and agitation significantly affected gentamicin concentration, productivity and biomass formation. The maximum gentamicin concentration of 4.12 g l(-1) and the highest yield of gentamicin on substrate 0.967 g g(-1) were obtained at impeller speed of 200 rpm and aeration rate of 2 vvm. Under optimal culture conditions in STR the production of gentamicin could be increased 3 fold when compared with shake flask.