Analyse des facteurs influençant la production de protéase par des Aspergillus marins.

Abstract

Endophytic fungi associated with marine algae represent a promising resource for the production of hydrolytic enzymes of industrial interest. The present study aimed to investigate the factors affecting the production of an extracellular protease by fungal isolates obtained from marine algae collected from the beaches of Salamandre and Sidi Lakhdar in the Mostaganem province. A methodological approach was carried out, including fungal isolation, purification, and both macroscopic and microscopic identification. Qualitative screening of proteolytic activity on skim milk agar enabled the selection of the isolate exhibiting the highest proteolytic activity, which was identified as Aspergillus terreus. This species was subsequently cultivated under submerged fermentation conditions to evaluate its ability to secrete an extracellular protease. The crude enzyme extract was recovered after an incubation period under agitation through filtration followed by centrifugation. The influence of different culture parameters, including pH, temperature, incubation time, and carbon source, on protease production was evaluated. Enzymatic activity was determined under each experimental condition. The results revealed a maximum protease activity of 88.018 U/mL under the following optimal conditions: pH 8, temperature of 28 °C, incubation period of 5 days, and glucose as the carbon source. In conclusion, the marine-derived Aspergillus terreus strain isolated in this study demonstrates significant biotechnological potential for protease production. Optimization of production parameters appears essential for enhancing enzyme yield and promoting its potential industrial applications.