Evaluation of protein content and antimicrobial activity of biomass fromSpirulinacultivated with residues from the brewing process

Abstract

BACKGROUND: Spirulina is a microalga that has a high protein content, in addition to having nutritional and pharmaceutical properties; therefore, it is a potential source for obtaining bioactive peptides. The obtaining of biocomposites of interest from microalgal biomass can be influenced by factors of cultivation, such as aeration, temperature, culture medium, and pH. Thus, this work aimed at evaluating the protein contents and antimicrobial activity of hydrolyzed and non-hydrolyzed biomass of the Spirulina microalgae grown under optimized conditions of the brewing residue by applying Design of Experiments (DOE) framework. The influence of airflow and concentration of brewing residue on microalgal culture was firstly analyzed using the Design of Experiments technique. The cultivation was carried out on a larger scale with subsequent enzymatic hydrolysis of the microalgal protein extract to analyze the hydrolysis degree, protein content, and antimicrobial activity. RESULTS:The results obtained indicated that there are no significant effects of the factors evaluated on the response variables. However, the obtained biomass showed a high protein content, above 51.88%. Regarding the extraction and hydrolysis of microalgae proteins, a degree of hydrolysis of 52.28% was obtained; however, the analyzed samples did not show antimicrobial activity under the studied conditions. CONCLUSION: Thus, it is demonstrated that the cultivation of Spirulina with residues from the brewing process has the potential for obtaining compounds of interest, such as proteins.

Mechanisms of Sodium-Acetate-Induced DHA Accumulation in a DHA-Producing Microalga, Crypthecodinium sp. SUN

“…Except for starches and lipids, protein is another essential component; it is mainly used as enzymes involved in multiple enzymatic reactions and constitutes structural components in cells [ 28 ]. Variations in the protein content in Crypthecodinium sp.…”