Allelochemicals stimulation (ACS) strategy: Potential for studying allelopathy and discovery of phytotoxins

This study simulated the natural cultivation conditions of fungi to investigate the relationship between host plants and their endosymbiotic microorganisms. By supplementing the culture medium with para-hydroxybenzoic acid (p-HB), three previously unreported acylated amino acid compounds, asperamides A-C (1-3), were isolated and identified from the seagrass-derived fungus Aspergillus fumigatiaffinis SYSU-6786. These compounds exhibited significant phytotoxic activity. In response to the novel observation that microorganisms can produce bioactive substances to influence their host under allelochemical stimulation, the "Allelochemicals Stimulation (ACS)" strategy was proposed to account for this phenomenon. To test the general applicability of this strategy, similar experiments were conducted using another seagrass-derived fungus, Aspergillus alabamensis SYSU-6778, which further supported the universality of the ACS strategy. This approach enhances the understanding of the allelopathic interactions between host plants and their associated fungi and may serve as a valuable tool for future investigations into fungal chemical ecology and natural product discovery.