Optimization of bioactive compound extraction from Brazilian forest bark species: effects of solvent mixtures on metal ion chelation and urease enzyme inhibition

Abstract The bark of forest species is a resource with a high concentration of bioactive compounds that have antioxidant, chelating and antimicrobial properties. Bioprospecting bioactive compounds from bark can generate income for local communities and contribute to the social and economic development of rural areas, especially in regions where traditional logging activity is in decline. Optimizing extraction is crucial to ensure that extracts with a high content of bioactive compounds are obtained. In this study, we optimized the extraction of bioactive compounds from the bark of Stryphnodendron adstringens and Myrcia eximia , evaluating the effects of mixtures of water, ethanol, and acetone on the chelation of Fe(II), Zn(II), and Cu(II) ions and on the inhibition of the urease enzyme. The results showed that both extracts have chelation and urease inhibition capacity. The simplex–centroid experimental design identified the ideal formulations for each response. Notably, maximum urease inhibition was achieved with a mixture of 7% water, 50% ethanol, and 43% acetone for S. adstringens and a mixture of 8% water, 75% ethanol, and 17% acetone for M. eximia . These findings highlight the importance of optimizing extraction conditions for each species, as efficiency is sensitive to solvent polarity and material matrix.