Identification of a Novel Antibiotic from Myxobacterium Stigmatella Eracta WXNXJ-B and Evaluation of its Antitumor Effects In-vitro

This work was to isolate and identify the bioactive secondary metabolite which was produced by myxobacterium stigmatella eracta wxnxj-b, and to evaluate its antitumor and apoptosis-inducing effects. the results showed that one novel compound (molecular formula c29h25no3) was isolated, purified by sephadex lh-20 column chromatography and preparative rp-hplc, and identified as 5-(6-benzyl-quinolin-3-ylmethyl)-6- phenyl-3,7-dioxa- bicycle [4.1.0] heptan-3-one (named as quinoxalone) according to its uv, ir, hrms and nmr spectra. the compound showed strong antitumor activity on b16, hepg2, mcf-7, sgc-7901, mdamb231 and ct-26 six tumor cell lines in-vitro. nevertheless, it showed less cytotoxic to the mouse normal spleen cells (ic50 was 836.27 ± 13.02 μg ml-1). the cytotoxic study on hepg2 cells in-vitro showed that quinoxalone could induce the change of cell nuclear and arrested the cell division in the s and g2/m phase. our results suggest that quinoxalone could be a potential anti-cancer agent.