Análise das propriedades físico-químicas e do potencial antimicrobiano do extrato de propolis de abelhas sem ferrão como conservante alternativo em queijos

Abstract

The search for natural alternatives to synthetic preservatives has driven research involving bioproducts such as stingless bee propolis, which is rich in phenolic compounds and flavonoids with well-documented antioxidant and antimicrobial activities. This study aimed to evaluate the physicochemical properties, antioxidant capacity, and antimicrobial potential of aqueous and hydroalcoholic extracts of propolis from four native stingless bee species: Tetragona clavipes (Borá), Scaptotrigona polysticta (Benjoí), Scaptotrigona bipunctata (Tubuna), and Tetragonisca angustula (Jataí). The extracts were analyzed for extraction yield, wax content, insoluble residue, total phenolic compounds (Folin–Ciocalteu), total flavonoids (AlCl3), antioxidant activity (DPPH), and antibacterial activity against Staphylococcus aureus and Escherichia coli through Minimum Inhibitory Concentration (MIC)and Minimum Bactericidal Concentration (MBC) assays. Hydroalcoholic extracts exhibited higher concentrations of bioactive compounds and better performance in the analyses, particularly the extract from T. clavipes, which showed 2.2912 mgGAE/mLEP of total phenolics, 1477 µMTE/mLEP of antioxidant activity, and MIC/MBC values of 0.24 mg/mL against S. aureus. Statistical analysis revealed significant differences (p < 0.05) among species and extract types. Although the levels of insoluble residue exceeded the limits established for Apis mellifera propolis, these results reflect the natural characteristics of stingless bee propolis, which contains cerumen and incorporates more solid materials, highlighting the need to revise current quality standards. It is concluded that stingless bee propolis, especially in its hydroalcoholic form, presents high potential as a natural preservative in the food industry, particularly for application in cheese, contributing to enhanced microbiological safety, extended shelf life, and the valorization of Brazilian apicultural biodiversity.