Secondary Metabolites from Aspergillus sparsus NBERC_28952 and Their Herbicidal Activities.

Fungi have been used in the production of a wide range of biologically active metabolites, including potent herbicides. In the search for pesticides of natural origin, NBERC_28952, a fungal strain with herbicidal activity, was obtained. Chemical study of secondary metabolites from NBERC_28952 resulted in the isolation of three new asperugin analogues, named Aspersparin A-C (-), and a new azaphilone derivative, named Aspersparin D (), together with two known compounds, Asperugin B () and sydonic acid (). The structures of these compounds were elucidated based on extensive spectroscopic data and single-crystal X-ray diffraction analysis. All of the isolated compounds were evaluated for their herbicidal activities on seedlings of and through Petri dish bioassays. Among them, compounds and exhibited moderate inhibitory activities against the growth of the roots and shoots of . seedlings in a dose-dependent manner, while showed obvious inhibitory effect on seedlings of . with an inhibitory rate of 78.34% at a concentration of 200 μg/mL. These herbicidal metabolites represent a new source of compounds to control weeds.