Abstract:To screen strains with antibacterial and antitumor activity, pregnenolone was used as the sole carbon source for screening bacteria from soil. Based on bacteriostatic activity assay, Pseudomonas aeruginosa HBD-12 was found to be effectively inhibiting the growth of Escherichia coli, Bacillus thuringiensis, Penicillium digitatum and Penicillium italicum, and its fermentation broth was separated and purified using column chromatography. Then, structure of the obtained monomeric compounds was analyzed by spectrum analysis, and their antitumor activity was measured using HTRF kinase detection kit. The isolated monomeric compounds 1-hydroxy-9,10-phenanthroline and 3-hydroxy-9,10-dihydrophenanthroline had significant antitumor activity. At 20 μg/mL, 1-hydroxy-9,10-phenanthroline and 3-hydroxy-9,10-dihydrophenanthroline inhibited 78.39±2.29% and 60.34±8.35% Aurora kinase A, respectively. Therefore, the secondary metabolites of Pseudomonas aeruginosa HBD-12 have the potential to develop antibacterial and antitumor drugs.