Ruann Janser Soares de Castro

Biologically active peptides: Processes for their generation, purification and identification and applications as natural additives in the food and pharmaceutical industries

Recent technological advances have created great interest in the use of biologically active peptides. Bioactive peptides can be defined as specific portions of proteins with 2 to 20 amino acids that have desirable biological activities, including antioxidant, anti-hypertensive, antithrombotic, anti-adipogenic, antimicrobial and anti-inflammatory effects. Specific characteristics, including low toxicity and high specificity, make these molecules of particular interest to the food and pharmaceutical industries. This review focuses on the production of bioactive peptides, with special emphasis on fermentation and enzymatic hydrolysis. The combination of different technologies and the use of auxiliary processes are also addressed. A survey of isolation, purification and peptide characterization methods was conducted to identify the major techniques used to determine the structures of bioactive peptides. Finally, the antioxidant, antimicrobial, anti-hypertensive, anti-adipogenic activities and probiotic-bacterial growth-promoting aspects of various peptides are discussed.

Protease from Aspergillus oryzae: Biochemical Characterization and Application as a Potential Biocatalyst for Production of Protein Hydrolysates with Antioxidant Activities

This study reports the biochemical characterization of a protease from Aspergillus oryzae LBA 01 and the study of the antioxidant properties of protein hydrolysates produced with this protease. The biochemical characterization showed that the enzyme was most active over the pH range 5.0–5.5 and was stable from pH 4.5 to 5.5. The optimum temperature range for activity was 55–60°C, and the enzyme was stable at temperatures below 45°C. The activation energy () for azocasein hydrolysis and temperature quotient () were found to be 37.98 kJ mol−1 and 1.64–1.53 at temperature range from 30 to 55°C, respectively. The enzyme exhibited of 97.63 min and a value of 324.31 at the optimum temperature for activity (57.2°C). Protease from A. oryzae LBA 01 was shown as a potentially useful biocatalyst for protein hydrolysis, increasing the antioxidant activities of soy protein isolate, bovine whey protein, and egg white protein from 2.0- to 10.0-fold.

Improving antioxidant activity of black bean protein by hydrolysis with protease combinations

This study explored the use of a simplex centroid design to produce protein hydrolysates with antioxidant properties using Alcalase 2.4L, Flavourzyme 500L and Neutrase 0.8L. Proteases kinetic parameters and the ultrafiltration of protein hydrolysates were also investigated. The highest antioxidant activity, in the studied conditions, was reached when the mixture of Alcalase 2.4L and Flavourzyme 500L was used in the hydrolysates production. The antioxidant power of the black bean proteins, measured by the total antioxidant capacity and reducing power assay, increased after hydrolysis by 31% and 70%, respectively. The black bean proteins hydrolysates fractions (3–30 kDa) showed an antioxidant activity decrease along with a reduction in molecular weight, demonstrating that a set of varied molecular weight peptides was responsible for the antioxidant characteristics of black bean protein hydrolysates.

Determinação das propriedades físico-químicas de hidrolisados de concentrado proteico de vísceras de frango como parâmetro para aplicações tecnológicas e funcionais

Resumo O objetivo do presente estudo foi avaliar a hidrólise enzimática de concentrado proteico obtido a partir de farinha de vísceras de frango utilizando diferentes preparações enzimáticas de proteases. Os hidrolisados proteicos obtidos foram avaliados quanto às suas propriedades físico-químicas, as quais incluíram solubilidade, estabilidade térmica, propriedades emulsificantes e capacidade de formação de espuma.

Chicken viscera protein concentrate as a source of bioactive peptides: enzymatic hydrolysis as a strategy to enhance the angiotensin I-converting enzyme (ACE) inhibitory activities

In this study, protein hydrolysates from chicken viscera were obtained using different commercial proteases and a statistical mixture design. The protein hydrolysates obtained were used as a source of bioactive peptides with angiotensin I-converting enzyme (ACE) inhibitory activities (antihypertensive activity). The results from this research showed that the chicken viscera protein concentrate in its non-hydrolyzed form (control) was able to inhibit 73.9% of the activity of the angiotensin I-converting enzyme (ACE) at 1mg/mL. On the other hand, enzymatic hydrolysis enhanced the biological properties of the proteins, increasing their ACE inhibitory activities. The maximum values of inhibition detected were 82.1, 82.5 and 83.7% using the binary mixture of Flavourzyme® 500L (50%) and Alcalase® 2.4L (50%), the ternary mixture of Flavourzyme® 500L (33.33%), Alcalase® 2.4L (33.33%) and Neutrase® 0.8L (33.33%) and Neutrase® 0.8L (100%), respectively.

Enzymatic hydrolysis of bean protein concentrates for the production of antioxidant peptides using a statistical mixture design

In this study, hydrolysates from three different varieties of bean protein concentrate were obtained using the commercial proteases Flavourzyme® 500L, Alcalase® 2.4L and Neutrase® 0.8L and a statistical mixture design for study of their antioxidant properties. The results from this research demonstrated the viability of applying commercial protease preparations singly and combined for protein hydrolysis, thus increasing the antioxidant activities of the bean protein concentrates from different varieties.