Through genome mining, a type II polyketide synthase (PKS) gene cluster was identified within the genome of Streptomyces sp. YINM00050. This gene cluster exhibits a high degree of similarity to the biosynthetic gene cluster responsible for the production of alnumycin, a benzoisochromanequinone (BIQ) compound. Nevertheless, no BIQs were isolated from the fermentations of the wild-type strain YINM00050 using various media. Subsequently, the global regulatory plasmid pSH152-tRNA-Asp-AUC was introduced into the wild-type strain, thereby generating the mutant strain YINM00050- tRNA. The subsequent fermentation of this mutant strain enabled the targeted isolation of BIQs. Moreover, a novel anti-tumor compound, alnumycin E, was identified.

Two new linear furocoumarins were isolated from Notopterygium incisum using silica gel, gel Sephadex LH-20 column chromatography, and preparative high-performance liquid chromatography. The structures of the new compounds were elucidated through analysis of spectroscopic evidence, including data obtained from high-resolution electrospray ionization mass spectrometry (HRESIMS) and nuclear magnetic resonance (NMR). The absolute configurations of Notoprenylate L (1) and Nototerprinol K (2) were further confirmed using electronic circular dichroism (ECD) calculations. Compound 1 demonstrated the ability to inhibit the expression of nitric oxide (NO), a pro-inflammatory factor, in lipopolysaccharide-induced RAW264.7 macrophages at a concentration of 7.5 μmol/L, indicating its potential for anti-inflammatory activity.