Curvulin and spirostaphylotrichins R and U from extracts produced by two endophytic Bipolaris sp. associated to aquatic macrophytes with antileishmanial activity

Abstract

In the present study, biological activity and chemical composition of two crude extracts of endophytic fungal strains of Bipolaris genera isolated from two species of aquatic macrophytes: Eichhornia azurea (Kunth) and Eichhornia crassipes (Mart.) were investigated. The nuclear magnetic resonance and mass spectrometry data provided the identification of three main compounds: curvulin (1), spirostaphylotrichin R (2) and U (3). The fragmentation mechanism of the precursor ions towards collision induced dissociation (CID) tandem mass spectrometry experiment (MS/MS) is also proposed. Furthermore, biological screening of the crude extracts displayed antileishmanial activity with IC values ranging from 70-84.2 μg.mL.

Curvulin and Phaeosphaeride A from Paraphoma sp. VIZR 1.46 Isolated from Cirsium arvense as Potential Herbicides

“…The identification of curvulin was also supported from the data from its ESI MS spectrum ( Figure S5 ) which, beside the expected sodium cluster [M + Na] + and the pseudomolecular ion [M + H] + at m / z 261 and 239, respectively, showed the significant fragmentation ions, not previously reported, at m / z 211, 197, 193, 165 generated from the pseudomolecular ion by alternative loss of C 2 H 4 , CH 2 CO, C 2 H 5 OH, C 2 H 5 CO 2 H, while the ion observed at m / z 123 was produced by the latter ion at m / z 165 by loss of CH 2 CO. When curvulin was isolated from both Curvularia siddiqui and Curvularia lunata no any biological activity was reported but when it was more recently isolated from two Bipolaris strains and two Eichhornia macrophytes species, together with spirostaphylotrichin R and U, the three metabolites showed antileishmanial activity [ 33 ]. However, this is the first report on the isolation of curvulin from a Paraphoma sp.…”

The identification and deletion of the polyketide synthase‐nonribosomal peptide synthase gene responsible for the production of the phytotoxic triticone A/B in the wheat fungal pathogen Pyrenophora tritici‐repentis

“…Given the metabolic cost of producing specialized metabolites, a survival advantage is presumed to be necessary for the retention of the biosynthetic capacity (Calvo et al ., ; Pickens et al ., ). Triticones have been investigated for a wide range of biological activities including anti‐influenza (Wang et al ., ), anti‐leishmanial (de Almeida et al ., ) and phytotoxicity (Sugawara et al ., ; Hallock et al ., ; Masi et al ., ); however, their role in the pathogenicity of Ptr on wheat has never been directly tested. Deletion of TtcA in Ptr prevented the production of the all triticone compounds but did not noticeably impact the degree of virulence of M4 on wheat.…”

“…Triticones A to F were first purified from Ptr culture filtrates but have since been found, along with an additional 18 other triticone compounds, in 5 other ascomycete fungi, Staphylotrichum coccosporum, Curvularia pallescens, Pyrenophora seminiperda, Cochliobolus lunatus and Bipolaris spp. Tamm, 1989a,b, 1990;Hallock et al, 1993;Abraham et al, 1995a;de Almeida et al, 2017;Wang et al, 2018). Triticone A and B are known to be phytotoxic, producing yellowishbrown lesions following leaf puncture assays on a range of hosts including wheat.…”

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

“…The fractionation led to seven compounds including 10-acetyl trichoderonic acid A (21), 6′-acetoxy-piliformic acid (22), 5′,6′-dehydropiliformic acid (23), piliformic acid (24), hydroheptelidic acid (25), xylaric acid D (26), and cytochalasin D (27) [36]. Similarly, three new azaphilones named mycoleptones A, B, and C (36)(37)(38) along with austdiol (39), eugenitin (40), 6-methoxyeugenin (41), and 9-hydroxyeugenin (42), were also isolated from extract of Mycoleptodiscus indicus, a fungus associated with the medicinal plant Borreria verticillata. When tested for their antileishmanial activity, all the seven compounds exhibited moderate to weak potency [37].…”

“…Curvulin (43), spirostaphylotrichins R (44) and U (45) were identified as the main components. These compounds exhibited moderate antileishmanial activity with IC 50 values ranging from 70-84.2 μg/mL [38]. An endophytic fungus Fusarium tricinctum isolated from fruits of Hordeum sativum Jess was reported to produce well-known antibiotics compounds Enniatins A, A1, B, B1, B2 and Q exhibiting moderate antileishmanial activity [39].…”