Avaliação do potencial antioxidante de extrato contendo pigmento extraído de Spirulina platensis

Abstract

The high demand for natural and sustainable ingredients, promote the use of cyanobacteria such as Spirulina platensis, in the food, pharmaceutical and cosmetic industries. The present study aimed to evaluate the antioxidant activity of a natural extract obtained from the cyanobacteria Spirulina platensis using the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical method. For this purpose, the extraction of bioactive pigments from the cyanobacteria was performed based on the orbital agitation methodology. The analyses were carried out at Laboratory D002 of the Federal Technological University of Paraná, in which the parameters temperature, concentration, and pre-treatment were evaluated, in triplicate samples. After the extraction process, the results indicated that the temperature of 30 °C favored higher concentration and purity of phycocyanin (pigment that has bioactive activities), while higher temperatures (50 °C) promoted protein degradation. Moreover, a biomass proportion of 0.1 g/mL resulted in higher pigment yield. Subsequently, the obtained extracts were subjected to the DPPH assay to determine antioxidant activity. It was observed that the concentration of 0.1 g/mL showed a higher percentage of radical inhibition compared to 0.08 g/mL, demonstrating a direct relationship between extract concentration and antioxidant efficiency. The sample maintained at 30 °C exhibited a slower response, stabilizing after 60 minutes, whereas the one at 50 °C showed a continuous increase in inhibition, reaching values above 100% at 90 minutes, possibly due to optical interference or radical instability. It is concluded that Spirulina platensis is a promising source of phycocyanin and natural antioxidant compounds, presenting high potential for application in the pharmaceutical, food, and cosmetic industries due to its ability to neutralize free radicals and its stability under controlled thermal conditions.