Muscotoxins are cyanobacterial cyclic lipopeptides with potential applications in biomedicine and biotechnology. In this study, Desmonostoc muscorum CCALA125 strain extracts were enriched by polymeric resin treatment, and subjected to HPCCC affording three cyclic lipopeptides (1–3), which were further repurified by semi-preparative HPLC, affording 1, 2, and 3, with a purity of 86%, 92%, and 90%, respectively. The chemical identities of 2–3 were determined as muscotoxins A and B, respectively, by comparison with previously reported ESI-HRMS/MS data, whereas 1 was determined as a novel muscotoxin variant (muscotoxin C) using NMR and ESI-HRMS/MS data. Owing to the high yield (50 mg), compound 2 was broadly screened for its antimicrobial potential exhibiting a strong antifungal activity against Alternaria alternata, Monographella cucumerina, and Aspergillus fumigatus, with minimum inhibitory concentration (MIC) values of 0.58, 2.34, and 2.34 µg/mL; respectively, and weak antibacterial activity against Bacillus subtilis with a MIC value of 37.5 µg/mL. Compounds 1 and 3 were tested only against the plant pathogenic fungus Sclerotinia sclerotiorum due to their low yield, displaying a moderate antifungal activity. The developed chromatographic method proved to be an efficient tool for obtaining muscotoxins with potent antifungal properties.

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The efficacy of entomopathogenic fungi from genus Lecanicillium, Isaria, Beauveria, and Purpureocillium were tested against larvae and adults of bean weevil (Acanthoscelides obtectus Say.). Some strains of Lecanicillium, Isaria and Beauveria showed obvious efficacy against adults of bean weevil but no treatment of bean seeds prevented the reproduction of adults, oviposition nor subsequent infestation of bean seeds.

Ondřej M., Cagaš B., Ondráčková E. (2010): Effect of the mycoflora of ergot (Claviceps purpurea) sclerotia on their viability. Plant Protect. Sci., 46: 66-71.Twenty fungal species were isolated from sclerotia of ergot (Claviceps purpurea) originating from rye. In in vitro tests with the anamorphic stage of ergot (known as Sphacelia segetum) high mycoparasitic activity was exhibited only by two of them -Clonostachys rosea and Trichoderma harzianum, moderate mycoparasitic activity was detected in Ulocladium sp., Clonostachys catenulata, Trichoderma hamatum, and Trichothecium roseum. In in vitro tests of mycoparasitic activity with sclerotia of the fungus Sclerotinia sclerotiorum their rapid and total destruction was brought about only by the fungi Clonostachys rosea and Trichoderma harzianum. The viability of overwintering ergot sclerotia in the soil was influenced by their placement, age, depth of placement and treatment with a conidial suspension of the fungus Clonostachys rosea. The highest viability values were reported in fresh one-year-old sclerotia. In two-year-old sclerotia their viability was reduced and their sensitivity to microbial activity was higher. The sclerotia aged 3 years or more did not germinate and were all microbiologically degraded in the soil. More than 80% of degradation of sclerotia which were 1 to 2 years old was caused by the fungus Clonostachys rosea. The degradation of sclerotia aged 3 to 4 years was brought about by bacteria, soil edafauna (mites, nematodes) and fungi of the genera Trichoderma, Fusarium, Clonostachys, etc.