[Isolation, purification and antitumor activity of Bacillomycin D from Bacillus amyloliquefaciems Q-426]

Cyclic lipopeptide has extensive application prospect in the field of medicine due to its unique chemical structure and biological activity. This study aims to obtain high purity of cyclic lipopeptide monomer from Bacillus amyloliquefaciems strain Q-426, and illuminate preliminary antitumor mechanism of C-15 Bacillomycin D and C-16 Bacillomycin D. Firstly, crude cyclic lipopeptide solution was prepared by two-steps purification of acid precipitation and double-resins chromatography. In order to obtain purer product preparative HPLC was utilized to separate and purify cyclic lipopeptide. Component 1 and component 2 were detected as C-15 Bacillomycin D and C-16 Bacillomycin D by HPLC-MS and ESI-MS/MS. Secondly, the effect of C-15 Bacillomycin D, C-16 Bacillomycin D and their mixture (1:1, mol:mol) on cell proliferation was measured using human cancer cells (Hela, MG, Hep-G2 and HT-29). The cyclic peptide showed a dose dependent manner on the cell proliferation inhibition of Hela and MG cells. Finally, the results of the scratch wound healing assay and FACS analysis revealed that C-16 Bacillomycin D can effectively influence the cells migration and the cells treated with C-16 Bacillomycin D showed typical apoptotic morphology with the increase of drug concentration in the early apoptosis, late apoptosis percentage increased, and G₀G₁ arrest was induced significantly.