Use of water hyacinth as a substrate for the production of filamentous fungal hydrolytic enzymes in solid-state fermentation

Abstract

The objective of the present work was to evaluate the water hyacinth (WH) as a substrate for the production of hydrolytic enzymes (cellulases and hemicellulases) of 100 strains of filamentous fungi under conditions of solid growth. Five fungal strains, identified as Trichoderma harzianum, Trichoderma atroviride, Penicillium griseofulvum, Penicillium commune and Aspergillus versicolor, were selected and studied for their ability to grow on water hyacinth as a substrate and carbon source only, evaluating hydrolytic enzymatic activities (α-l-arabinofuranosidase, cellulase, xylanase and β-d-xylopyranosidase) and extracellular protein per g of water hyacinth dry matter (gdm). The five strains selected were able to produce the four enzymes studied; however, T. harzianum strain PBCA produces the highest xylanase (149.3 ± 14.3 IU/gdm at 108 h), cellulase (16.4 ± 0.6 IU/gdm at 84 h) and β-d-xylopyranosidase (127.7 ± 14.8 IU/gdm at 48 h). In contrast, the fungus with the highest α-l-arabinofuranosidase activity was A. versicolor, with 129.8 ± 13.3 IU/gdm after 108 h. In conclusion, T. harzianum showed the best production of the hydrolytic enzymes studied, using as a matrix and carbon source, water hyacinth. In addition, catalytic activities of arabinofuranosidase and xylopyranosidase were reported for the first time in T. versicolor and T. harzianum.