A streamlined high throughput screening method for the Mycobacterium neoaurum mutants with expected yield of biotransformation derivatives from sterols

Steroidal drugs have wide indications such as anti-inflammation, anti-tumor, endocrine regulation,fertility management. Phytosterol is the main starting materials for the industrial synthesis of steroid drugs. Microbial transformation of phytosterol is a simple and environmentally friendly process. Efficient microbial strains for industrial phytosterol transformation are critical for the commercial success. To this end, a 96-well plate based method was developed to discriminate the mixture of 4-androstene-3,17-dione, androsta-1,4-diene-3,17-dione, and bisnoraldehyde, with different ratio of the 3 components in the mixture, which mimics the sterol bioconversion products by using the Mycobacterium neoaurum. The M. neoaurum bioconversed broth test using phytosterol as substrate also found that the spectrum methodology can evaluate the relative content of different compounds. The method is practical, high throughput and can replace the conventional HPLC-based assay for rapid selection of desired microbial strains.

红葱的化学成分研究

目的研究红葱Eleutherine americana的化学成分。方法采用硅胶柱色谱、Sephadex LH-20柱色谱及重结晶等方法,分离纯化红葱的化学成分,通过MS、NMR等波谱技术确定化合物结构。结果确定了7个化合物的结构,分别为9-hydroxy-8-methoxy-1-methyl-1,3-dihydronaphtho[2,3-c]furan-4-O-β-D-glucopyranoside(1)、eleutherinoside A(2)、豆甾醇-3-O-β-D-葡萄糖苷(3)、kadsuric acid(4)、豆甾醇(5)、1,2-二羟基-8-甲氧基-3-甲基蒽醌(6)、9-methoxy-1,3-dimethyl-1H-naphtho[2,3-c]pyran-5,10-dione(7)。结论化合物1为新化合物,命名为红葱新苷。化合物3～5为首次从该植物中分离得到,化合物6和7为首次获得的新天然产物。