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Enzymes are important raw material for the detergent industry. In order to develop enzymes for detergents, Bacillus licheniformis D5, a strain with high alkaline protease production, was screened in this study. The alkaline protease production was optimized using response surface methodology (RSM). The optimized fermentation medium (w/v) consisted of soybean cake flour (4.0%), peanut cake flour (2.69%), beef paste (0.95%), maltodextrin (4.0%), glucose (2.23%), KCl (0.1%), KH2PO4 (0.2%), K2HPO4·12H2O (0.40%), CaCl2 (0.04%), MgSO4·7H2O (0.04%), Tween-80 (0.05%) and serine (0.05%). The fermentation level increased by 2.12-fold compared with the control. The culture temperature was 33°C, and the initial pH was 10. The fed-batch fermentation was performed in a 30 L fermenter. The fermentation level was increased by 47.4% (from 43,587 U/mL to 60,830 U/mL), and the fermentation time was shortened from 78 h to 54 h. The results demonstrated significantly improved fermentation level, reduced fermentation cost, simplified large-scale production of alkaline protease, and thereby promote application of alkaline protease in detergent industry. [ABSTRACT FROM AUTHOR]