AVALIAÇÃO MICROBIOLÓGICA DE SUPLEMENTOS COMERCIAIS À BASE DE SPIRULINA PLATENSIS

Abstract

The consumption of dietary supplements based on Spirulina platensis has become increasingly popular, mainly due to its high nutritional value, functional properties, and safety profile when properly processed. S. platensis is a blue-green filamentous cyanobacterium known for its high protein, vitamin, mineral, and antioxidant content. Therefore, it is widely used as a nutritional supplement, available in various commercial forms, such as capsules and powder. However, the microbiological quality and morphological authenticity of these products are not always guaranteed, which can affect their efficacy and safety for consumers. This study aimed to evaluate the microbiological and physicochemical quality and verify the presence of Spirulina platensis in commercial supplement samples purchased in the city of João Pessoa, Paraíba. Microbiological analyses included aerobic mesophilic microorganism counts, enterobacteriaceae counts, and yeast and mold counts, based on the criteria established by ANVISA Normative Instruction No. 161/2022. For the physicochemical analysis, water activity (Aw) and pH parameters were determined. For morphological analysis, the samples were examined under a brightfield optical microscope at 400× magnification to identify spiral filaments or curved fragments typical of cyanobacteria. The results showed that three of the four capsule samples were contaminated with microorganisms above the permitted limits, particularly molds, yeasts, and enterobacteria, indicating noncompliance with current legislation. However, the powder sample and one capsule sample were within the stipulated limits. Physicochemical analysis confirmed the vulnerability of the products, revealing that all samples had a water activity (Aw) above the safety threshold of 0.60, indicating inefficient drying. Morphological analysis confirmed the presence of Spirulina platensis in all samples through its fragmented filaments, demonstrating widespread structural damage resulting from processing, and revealed the presence of a visual contaminant in one of the brands. These results highlight the importance of strengthening oversight and quality control of these products, from manufacture to sale. The presence of contamination suggests potential health risks and raises doubts about the authenticity of some supplements available on the market. Therefore, we can conclude that, although Spirulina platensis is a nutritional source, its effectiveness as a supplement depends on strict adherence to good manufacturing practices and constant verification of its composition and integrity.