Characterization and bioactive potentials of secondary metabolites from Fusarium chlamydosporum

Abstract

A search for bioactive secondary metabolites from the endophytic fungus Fusarium chlamydosporum, isolated from the root of Suaeda glauca, led to the isolation of three indole derivatives (1–3), three cyclohexadepsipeptides (4–6), and four pyrones (7–10). The structures of new (1) and known compounds (2–10) were elucidated on the basis of extensive spectroscopic analysis. All these compounds were evaluated for phytotoxic, antimicrobial activities, and brine shrimp lethality. Compound 1 showed significant phytotoxic activity against the radicle growth of Echinochloa crusgalli, even better than the positive control of 2,4-D. Cyclohexadepsipeptides (4–6) and pyrones (7–10) exhibited brine shrimp lethality, especially 4 and 7 with the LD₅₀ values of 2.78 and 7.40 μg mL⁻¹, respectively, better than the positive control.

Graphical Abstract

Keywords:

• Endophytic fungus
• Secondary metabolites
• Phytotoxic activity
• Brine shrimp lethality
• Antimicrobial activity

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This project was supported by National Natural Science Foundation of China (No. 31401795), Key Research and Development Program of Shandong Province (No. 2016GSF121007 and 2018GSF121036), Applied Fundamental Research Program of Qingdao (No. 15-9-1-29-jch), and High-level Talents Foundation of Qingdao Agricultural University (No. 631419 and No. 631431).