Is There a Relationship between the Concentration of Phenolic Compounds and the Versatility of Medicinal Plants in the Caatinga Biome?

This study explored the correlation between concentrations of phenolic compounds (phenols, tannins, and flavonoids) and the versatility of woody medicinal plants in the Caatinga, a seasonally dry forest region in Brazil. We examined whether these compounds influence the versatility of plants used by populations, given their known therapeutic properties. Plants were categorized as high or low versatility based on their relative importance (RI) values ​​at the regional level. Samples collected in Catimbau National Park, Pernambuco, were analyzed using colorimetric methods: Folin-Ciocalteu reagent for total phenols, casein precipitation for tannins, and aluminum chloride complexation for flavonoids. Contrary to expectations, no significant differences in phenolic compound concentrations were found between the high and low versatility groups. Higher levels of total phenols and tannins were observed in Myracrodruon urundeuva and Anadenanthera colubrina, both highly versatile species. However, less versatile species, such as Mimosa tenuiflora and Schinopsis brasiliensis, also showed high levels. Flavonoid content, notably lower than phenols and tannins, did not show significant variation between groups. Although phenolic compounds contribute to the therapeutic properties of medicinal plants, their concentration alone does not determine the versatility of plants in the Caatinga. Versatility is more likely influenced by ecological conditions, cultural practices, and species availability. This study highlights the need to integrate multiple perspectives in ethnopharmacological research.