Bioactive secondary metabolites produced by an endophytic fungus Gaeumannomyces sp. JS0464 from a maritime halophyte Phragmites communis

Abstract

Endophytes, important plant-associated mycobionts, have attracted a great deal of attention because of their bioactive secondary metabolites. Even though halophytes have been reported to overcome salt stress via associations with their endophytes, few studies have investigated the metabolites produced by the endophytes from halophytes. In this study, a dark septate endophytic fungal strain (JS0464), identified as Gaeumannomyces sp. by ITS sequencing, was isolated from the rhizome of a halophyte, Phragmites communis, in Suncheon bay, South Korea. This strain was cultured on a large scale and extracted with ethyl acetate. Chemical investigations of extracts of JS0464 led to the isolation of two glycosylated dialkylresorcinol derivatives (1-2), an anthraquinone derivative (3) and eight known compounds (4-11), which were identified by spectroscopic analyses incorporating one-dimensional/2D NMR and MS. Nine compounds showed significant nitric oxide reduction activity in lipopolysaccharide-stimulated microglia BV-2 cells, seven of which did not impair cell viability. The results suggest that endophytes from the halophytes could be potential resources for bioactive natural products.

Anti-leishmanial and Anti-inflammatory Agents from Endophytes: A Review

“…A dozen studies reporting the activity of metabolites from endophytes of marine plants have been reported. [124]. In another investigation, three new sesquiterpenoids, trichoacorenols B-C and cyclonerodiol B, along with three known ones, isolated from the mangrove plant endophytic fungus Trichoderma sp.…”

Prospective Leads from Endophytic Fungi for Anti-Inflammatory Drug Discovery

“…5α,8α-epidioxy-(22E,24 R)-23-methylergosta-6,22-dien-3β-ol (44) Gaeumannomyces sp. Phragmites communis [14] 18. 5α,8α-epidioxyergosta-6,22-dien-3β-ol (38) Colletotrichum sp.…”

“…They are characterized by a highly substituted per hydro-isoindolone moiety to which a macrocyclic ring like a carbocycle, a lactone, or a cyclic carbonate is fused [54]. Four AI cytochalasan derivatives [cytochalasin J (12) and H (13), yamchaetoglobosin A (14), and phomopchalasin C (15)] from endophytic fungal sources were reported (▶ Fig. 2).…”

“…These compounds had been reported as NO and IL-6 inhibitors. Compound phomopsterone B (40) was found to be potentially active exhibiting IC 50 value of 4.65 µM (▶ Table 2) [14][15][16][17]43].…”

Secondary Metabolites of The Endophytic Fungus Alternaria alternata JS0515 Isolated from Vitex rotundifolia and Their Effects on Pyruvate Dehydrogenase Activity

“…Halophytes are plants that have adapted to growing in highly saline water, and they comprise only 2% of all plant species [8]. The relationships between halophytes and their endophytes could help the plants adapt to highly saline conditions [9].…”