BioTechnologia (Jun 2020)

Screening and identification of novel cellulolytic Trichoderma species from Egyptian habitats

  • Omar A. Hewedy,
  • A.M. El-Zanaty,
  • A.I. Fahmi

DOI
https://doi.org/10.5114/bta.2020.96413
Journal volume & issue
Vol. 101, no. 2
pp. 117 – 133

Abstract

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The present study aimed to isolate indigenous Trichoderma fungi possessing cellulolytic activities from different geographical locations in Egypt. Such strains can be used to convert crop residues to bioproducts, which presently is one of the most important issues in developing countries. The isolates were identified using molecular approaches and morphological characteristics. Favorable growth conditions for Trichoderma isolates (media & temperature) were assessed in vitro. The growth rate of Trichoderma isolates was assessed on two media, namely Potato Dextrose Agar (PDA) and Synthetic Nutrient Agar (SNA), and morphological parameters, i.e., shape, pigment, and edge were observed. A comparison of sequences encoding for internal transcribed spacer (ITS) and translation elongation factor 1-α (tef1 ) was conducted to determine the species. Cellulase assay was performed using different cellulose substrates (Swollen, CMC (low viscosity carboxymethylcellulose), and Avicel). Among the isolated fungi, Trichoderma viride EGY-T27 had the highest endoglucanase activity, while Trichoderma harzianum EGY-T30 showed the highest exoglucanase activity. A total of 27 strains of Trichoderma were identified using ITS, and the tef1 gene was sequenced for 23 strains. The tested strains were identified with acceptable quality based on ITS sequences, which ranged from 98 to 100%, except for strain MH908499 (85%). This research constitutes the most comprehensive study on screening for fungal strains with the highest biodegradable potential isolated from various locations in Egypt.

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