Informatics Publishing Limited

Gaston Ezequiel Ortiz ¹, Diego Gabriel Noseda ¹, Maria Clara Ponce Mora ¹, Matias Nicolas Recupero ¹, Martin Blasco ¹, Edgardo Alberto ¹

Affiliations
1 Instituto de Investigaciones Biotecnologicas-Instituto Tecnologico de Chascomus (IIB-INTECH), Universidad Nacional de San Martın (UNSAM) and Consejo Nacional de Investigaciones Cientıficas y Tecnicas (CONICET), San Martın, 1650 Buenos Aires, AR

Abstract

A comparative study of the proteolytic enzymes production using twelve Aspergillus strains previously unused for this purpose was performed by solid state fermentation. A semiquantitative and quantitative evaluation of proteolytic activity were carried out using crude enzymatic extracts obtained from the fermentation cultures, finding seven strains with high and intermediate level of protease activity. Biochemical, thermodynamics, and kinetics features such as optimum pH and temperature values, thermal stability, activation energy (E_a), quotient energy (Q ₁₀), K _m, and V_max were studied in four enzymatic extracts from the selected strains that showed the highest productivity. Additionally, these strains were evaluated by zymogram analysis obtaining protease profiles with a wide range of molecular weight for each sample. From these four strains with the highest productivity, the proteolytic extract of A. sojae ATCC 20235 was shown to be an appropriate biocatalyst for hydrolysis of casein and gelatin substrates, increasing its antioxidant activities in 35% and 125%, respectively.

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