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Five fungal endophytes, <italic>Alternaria</italic> sp., <italic>Aspergillus</italic> sp., <italic>Chaetomium</italic> sp., <italic>Rhizopus</italic> sp. and <italic>Curvularia</italic> sp., were isolated from an Egyptian herbaceous plant, <italic>Tribulus terrestris</italic>, and tested for their antibacterial activity against three phytopathogenic bacteria (<italic>Pectobacterium carotovorum</italic> subsp. <italic>carotovorum, Ralstonia solanacearum, Pseudomonas syringae</italic> pv. <italic>syringae</italic>). <italic>Chaetomium</italic> sp. showed the highest antibacterial activity. This strain was identified morphologically and molecularly as <italic>Chaetomium cochliodes</italic> MS03 (MW898133) based on the ITS1-5.8S rRNA-ITS2 genomic region. <italic>Chaetomium cochliodes</italic> caused 15 and 8 mm inhibition zones of <italic>P. carotovorum</italic> subsp. <italic>carotovorum</italic> and <italic>R. solanacearum</italic>, respectively. <italic>Chaetomium cochliodes</italic> isolate was fermented and extracted with ethyl acetate. The crude extract of <italic>C. cochliodes</italic> showed strong antibacterial activity against <italic>P. carotovorum</italic> subsp. <italic>carotovorum</italic> (inhibition zone = 27 mm). Bioassay guided isolation of the crude extract using silica gel column chromatography was conducted to isolate bioactive secondary metabolites. Minimum inhibitory concentrations (MICs) were 500, 32 and 4 mg/L for <italic>C. cochliodes</italic> extract, fraction 14 and fraction 15, respectively, against <italic>P. carotovorum</italic> subsp. <italic>carotovorum</italic>. Bioactive fractions were analyzed by GC/MS. The bioactive pure compound was identified as 9,12-octadecadienoic acid (Z,Z) and the chemical structure was confirmed by H1 NMR and C13 NMR spectral analysis. The isolated compound showed a promising antibacterial activity against <italic>P. carotovorum</italic> subsp. <italic>carotovorum</italic> with MIC value of 32 mg/L.
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Five fungal endophytes, Alternaria sp., Aspergillus sp., Chaetomium sp., Rhizopus sp. and Curvularia sp., were isolated from an Egyptian herbaceous plant, Tribulus terrestris, and tested for their antibacterial activity against three phytopathogenic bacteria (Pectobacterium carotovorum subsp. carotovorum, Ralstonia solanacearum, Pseudomonas syringae pv. syringae). Chaetomium sp. showed the highest antibacterial activity. This strain was identified morphologically and molecularly as Chaetomium cochliodes MS03 (MW898133) based on the ITS1-5.8S rRNA-ITS2 genomic region. Chaetomium cochliodes caused 15 and 8 mm inhibition zones of P. carotovorum subsp. carotovorum and R. solanacearum, respectively. Chaetomium cochliodes isolate was fermented and extracted with ethyl acetate. The crude extract of C. cochliodes showed strong antibacterial activity against P. carotovorum subsp. carotovorum (inhibition zone = 27 mm). Bioassay guided isolation of the crude extract using silica gel column chromatography was conducted to isolate bioactive secondary metabolites. Minimum inhibitory concentrations (MICs) were 500, 32 and 4 mg/L for C. cochliodes extract, fraction 14 and fraction 15, respectively, against P. carotovorum subsp. carotovorum. Bioactive fractions were analyzed by GC/MS. The bioactive pure compound was identified as 9,12-octadecadienoic acid (Z,Z) and the chemical structure was confirmed by H1 NMR and C13 NMR spectral analysis. The isolated compound showed a promising antibacterial activity against P. carotovorum subsp. carotovorum with MIC value of 32 mg/L.

Antibacterial potential of extracts and metabolites isolated from the endophytic fungus <italic>Chaetomium cochliodes</italic> against phytopathogenic bacteria

Department of Pesticide Chemistry and Technology

Faculty of Agriculture, El-Shatby, Alexandria University

Hellenic Plant Protection Journal

This work is licensed under the Creative Commons Attribution 4.0 International License.

Antibacterial potential of extracts and metabolites isolated from the endophytic fungus  against phytopathogenic bacteria

Five fungal endophytes, Alternaria sp., Aspergillus sp., Chaetomium sp., Rhizopus sp. and Curvularia sp., were isolated from an Egyptian herbaceous plant,...

Antibacterial potential of extracts and metabolites isolated from the endophytic fungus Chaetomium cochliodes against phytopathogenic bacteria

Published Online: Jul 18, 2024

Page range: 85 - 96

Received: Oct 02, 2022

Accepted: Jun 30, 2024

DOI: https://doi.org/10.2478/hppj-2024-0008

© 2024 M.M.G. Saad et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.