Optimization of the medium constituents for maximizing antibiotic production by marine actinomycete exhibiting promising antibacterial activity.

In order to improve the productivity of activities substance of actinomycetes SLB-8, the effects of the medium components, fermentation time, and initial PH on the biological activity of SLB-8 were investigated by detecting the mycelium growth inhibition rate of SLB-8. The results show that the inhibition rate is the highest under the optimum medium composition (g/L) containing sucrose 15.0, Malt extract 10.0, K2HPO4 0.5, MgSO4 0.5, NaCl 0.5 and FeSO4 0.01 Caco3 0.5. KNO3 1.0, Distilled water 1.0L The maximum antibiotic activity is obtained at the inoculation volume 10%, medium volume in 250 ml flask 50 ml, rotary speed of 180 r/min, fermentation time 4 days, temperature 28°C and initial pH 8.0. The inhibition rate has been increased by 6.71% under the optimized condition.