School of Life Science, Northeast Agricultural University, Harbin 150030, PR China.
J Agric Food Chem. 2010 Feb 10;58(3):1933-8. doi: 10.1021/jf9035194.
A strain Actinoplanes sp. HBDN08 was screened by PCR-guided method using primers derived from conserved regions of halogenase genes. A new chlorinated isoflavone, 3',8-dichlorogenistein (1), along with 8-chlorogenistein (2) were isolated from the fermentation broth of Actinoplanes sp. HBDN08. Their structures were elucidated on the basis of extensive 1D and 2D NMR as well as HRESI-MS, ESI-MS, UV, and IR spectroscopic analyses. The origin of the two compounds was also investigated by high-performance liquid chromatography (HPLC) analysis. The results demonstrated that they were not biosynthesized but derived from the biotransformation of genistein by Actinoplanes sp. HBDN08. The antioxidant activities of the isolated compounds 1 and 2 were evaluated by using the lipid peroxidation assay. Their antitumor activities were calculated according to the inhibitory rate of cell proliferation against the human breast cancer cell line MDA-MB-231. The results indicated that compounds 1 (IC(50) = 5.2 microM) and 2 (IC(50) = 7.5 microM) showed stronger antioxidant activities than genistein (IC(50) = 13.6 microM). In comparison with the antitumor activities of genistein, those of compounds 1 and 2 increased 7.7- and 2.6-fold, respectively. These results suggest that the PCR-guided screening strategy is a rapid method for obtaining halometabolite-producing strains. Moreover, these results reveal that chlorination has significant effects on the bioactivities of genistein. This could be important information for studying the structure-activity relationships of genistein.
一株放线菌 Actinoplanes sp. HBDN08 通过聚合酶链式反应（PCR）引导的方法，利用卤化酶基因保守区的引物进行筛选。从 Actinoplanes sp. HBDN08 的发酵液中分离得到了一种新的氯化异黄酮 3'，8-二氯染料木黄酮（1）和 8-氯染料木黄酮（2）。通过广泛的 1D 和 2D NMR 以及高分辨质谱（HRESI-MS）、电喷雾质谱（ESI-MS）、紫外（UV）和红外（IR）光谱分析确定了它们的结构。通过高效液相色谱（HPLC）分析还研究了这两种化合物的来源。结果表明，它们不是生物合成的，而是由 Actinoplanes sp. HBDN08 对染料木黄酮的生物转化而来。通过脂质过氧化测定法评价了分离得到的化合物 1 和 2 的抗氧化活性。根据对人乳腺癌细胞系 MDA-MB-231 的细胞增殖抑制率计算了它们的抗肿瘤活性。结果表明，化合物 1（IC50 = 5.2 μM）和 2（IC50 = 7.5 μM）的抗氧化活性强于染料木黄酮（IC50 = 13.6 μM）。与染料木黄酮的抗肿瘤活性相比，化合物 1 和 2 的活性分别提高了 7.7 倍和 2.6 倍。这些结果表明，PCR 引导的筛选策略是获得产生卤代谢物的菌株的快速方法。此外，这些结果表明氯化对染料木黄酮的生物活性有显著影响。这可能是研究染料木黄酮结构-活性关系的重要信息。
