【摘要】 在研究双孢菇的抗肿瘤活性成分时,发现其内生的一个枯草芽孢杆菌AB154的代谢产物,该产物具有较强的抑制人结肠癌Caco-2细胞活性。借助体外多种细胞毒活性跟踪测试,利用硫酸铵沉淀法和DEAESephadex阴离子交换柱层析,从枯草芽孢杆菌AB154发酵液中分离得到抑制人结肠癌Caco-2细胞的活性组分,其IC50为109.94μg/m L,而对人正常支气管上皮细胞（NHBE）的抑制作用较弱。经高效液相色谱（HPLC）制备,结合MALDI-TOF MS、ESI-MS/MS分析和查阅文献,从活性组分中分离鉴定了2个亚组分表面活性肽（surfactin）和丰原素（fengycin）B1类脂肽,其抑制人结肠癌Caco-2细胞的IC₅₀依次为80.7μg/m L和312.5μg/m L。此研究首次发现fengycin B1类脂肽具有抑制人结肠癌Caco-2细胞的活性,机理研究发现fengycin B1在12 h时将细胞周期阻滞在G₀/G₁期,在24 h时阻滞在S期,同时能够损伤肿瘤细胞的细胞核。更多还原

【Abstract】 A Bacillus subtilis AB154 with anti-proliferation activity on human cancer cells was isolated from the fruit body of white button mushroom（Agaricus bisporus）, when we studied the anti-tumor activity of A. bisporus mushroom. The peptide with proliferation inhibiting activity produced by endophyte Bacillus subtilis AB154 was extracted using ammonium sulfate precipitation and DEAE-Sephadex ion exchange chromatography, followed by anti-tumor activity investigation. The results showed that it had a better inhibitory activity against the human colon cancer cell line Caco-2 with IC₅₀ value of 109.94 μg/m L, while the inhibitory ability on human normal bronchial epithelial cell line NHBE was the lowest. Then a peptide component with anti-tumor ability was purified by the high performance liquid chromatography（HPLC）, and its structure was identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry（MALDI-TOF MS） and electro spray ionization tandem mass spectrometry（ESI-MS/MS）. The result showed that the peptide produced by Bacillus subtilis AB154 belonged to the lipopeptide family of fengycin B1. This research first reported an fengycin B1 lipopeptide with anti-human colon cancer cell Caco-2 activity. The study of inhibitory mechanism showed that the cell cycle of Caco-2 cells treated with fengycin for 12 h were arrested in the G₀/G₁ phase, and the cell cycle was arrested in the S phase at 24 h. The fragmentation of nuclear chromatin within Caco-2 cells was induced by fengycin.更多还原