Evaluation of the biological activities of peptides released from the hydrolysis of caprine casein by proteases synthesized by filamentous fungi

Author(s)

José Erick Galindo Gomes

• Document type: Doctoral Thesis
• Press: São José do Rio Preto. 2018-04-25.
• Institution: Universidade Estadual Paulista (Unesp). Instituto de Biociências Letras e Ciências Exatas. São José do Rio Preto
• Defense date: 2018-03-23
• Advisor: Roberto da Silva; Keila Aparecida Moreira

Abstract

Bioactive peptides are molecules of natural origin that can aid physiological functions in organisms. The present study aimed to produce proteases by different filamentous fungi, to hydrolyze caprine casein and to evaluate the potential of biological activities of the released peptides. Based on the results of hydrolysis degree (GH), which varied between 33.59% and 71.81% and in biological activities, the fungi Mucor subtilissimus URM 4133 and Mucor guilliermondii URM 5848 were chosen to continue the work. For the purification of both enzymes, a factorial design 24 was used, in order to verify the best conditions of enzymatic production. Protease activity was maximal at pH 8.5 at 45 °C for M. subtilissimus URM 4133 and at pH 8.0 at 40 °C for the M. guilliermondii URM 5848 enzyme; however, remained stable in practically every pH range and thermostable up to 40 ° C and 45 ° C, respectively. Both proteases were completely inhibited by phenylmethanesulfonyl fluoride (PMSF). Purified proteases from both fungi were used separately to hydrolyze caprine casein. The hydrolysates obtained in the time of 12 hours presented better general results of biological activities both for the protease of the fungus M. subtilissimus URM 4133 and for the protease of the fungus M. guilliermondii URM 5848. The antihypertensive activity presented results of 92.57 % and 83.42% for inhibition of angiotensin converting enzyme (ACE). Among the fractions separated in FLPC, the fraction P5 (URM 4133) and the fraction P3 (URM 5848) presented an IC50 of antihypertensive activity of 35.42 and 22.97 μg.mL-1, respectively. The peptides released were efficient to perform all the proposed biological activities, with emphasis on the inhibition of the enzyme ACE, which showed the potential of these molecules to assist in the control of blood pressure. (AU)

• FAPESP's process: 14/13700-3 - Evaluation of biological activity of peptides released from the hydrolysis of caprine casein by proteases synthesized by filamentous fungi
• Grantee: José Erick Galindo Gomes
• Support Opportunities: Scholarships in Brazil - Doctorate