Alkylated Salicylaldehydes and Prenylated Indole Alkaloids from the Endolichenic Fungus Aspergillus chevalieri and Their Bioactivities

• DOI: 10.1021/acs.jafc.1c01148
• Publication Date: 2021-06-07T13:19:42Z
• Authors: Li-Bin Lin; Yu-Qi Gao; Rui Han; Jian Xiao; Yi-Meng Wang; Qiang Zhang; Yi-Jie Zhai; Wen-Bo Han; Wen-Li Li; Jin-Ming Gao
• Keywords: Cereus; Phthalide

Sixteen metabolites, including seven C7-alkylated salicylaldehyde derivatives (1–7) and nine prenylated indole alkaloids (8–16), three of which are new, namely, asperglaucins A B (1 2) neoechinulin F (8), were separated from the endolichenic fungus Aspergillus chevalieri SQ-8. Asperglaucin (1) represents an unusual phthalide-like derivative with a benzo[c]thiophen-1(3H)-one scaffold. All compounds assessed in vitro for antibacterial, antineuroinflammatory, antioxidant activities. Notably, exhibited potent antibacterial activities against two plant pathogens Pseudomonas syringae pv actinidae (Psa) Bacillus cereus, MIC value 6.25 μM; further SEM analyses illustrated that possible bacteriostatic mechanisms 1 2 to alter external structure B. cereus Psa, cause rupture or deformation cell membranes, respectively, results suggest may serve as potential promising candidates lead agrochemical bactericides. Furthermore, 6 10 significantly inhibited nitric oxide production IC50 ca. 12 μM, anti-inflammatory involved also studied by molecular docking. Finally, tested phenolics 3–5 showed significant antioxidative effects. Thus, strain SQ-8 novel resource these bioactive metabolites be utilized.