Broussochalcones A (BCA, 1) and B (BCB, 2) are major bioactive constituents isolated from Broussonetia papyrifera, a polyphenol-rich plant belonging to the family Moraceae. Due to their low yields from natural sources, BCA (1) and BCB (2) were prepared synthetically by employing Claisen–Schmidt condensation, and these were used as substrates for microbial transformation to obtain novel derivatives. Microbial transformation of BCA (1) and BCB (2) with the endophytic fungus Aspergillus niger KCCM 60332 yielded 10 previously undescribed chalcones (1a–1e and 2a–2e). Their structures were established based on the spectroscopic methods. The cytotoxicity of BCA (1), BCB (2), and their metabolites (1a–1e and 2a–2e) was determined by human cancer cell lines A375P, A549, HT-29, MCF-7, and HepG2, with 1e shown to be most cytotoxic.

中文翻译：

---

黑曲霉对布鲁索查耳酮 A 和 B 的微生物转化

Broussochalcone A (BCA, 1 ) 和 B (BCB, 2 ) 是从Broussonetia papyrifera分离的主要生物活性成分，这是一种属于桑科的富含多酚的植物。由于天然来源的产量低，BCA ( 1 ) 和 BCB ( 2 ) 通过采用克莱森-施密特缩合合成制备，并将它们用作微生物转化的底物以获得新型衍生物。BCA ( 1 ) 和 BCB ( 2 ) 与内生真菌Aspergillus niger KCCM 60332 的微生物转化产生了 10 个以前未描述的查耳酮 ( 1a – 1e和2a )– 2e )。它们的结构是基于光谱方法建立的。BCA ( 1 )、BCB ( 2 ) 及其代谢物（1a – 1e和2a – 2e）的细胞毒性由人类癌细胞系 A375P、A549、HT-29、MCF-7 和 HepG2 确定，1e显示细胞毒性最强。