Bioactive compounds and therapeutic potential of the Brazilian genus Kielmeyera (Calophyllaceae): a comprehensive review.

The genus Kielmeyera Mart. (Calophyllaceae) comprises dozens of species, most of which are endemic to South American biomes, particularly the Cerrado, coastal ecosystem, and rupestrian grasslands. Several species have long been used in Brazilian traditional medicine for the treatment of inflammation, wound healing, gastrointestinal disorders, ulcers, leishmaniasis, fevers, and diverse infectious diseases. Despite the ecological and medicinal relevance of the genus, phytochemical and pharmacological investigations remain relatively limited. Available studies indicate that Kielmeyera species possess a specialized secondary metabolism rich in phenolic polyketide-derived compounds, especially xanthones and benzophenones, together with flavonoids and triterpenes. Based on the taxonomic treatment adopted in this review, we identified 55 accepted species of Kielmeyera. Of these, 22 species have been investigated phytochemically, whereas biological or pharmacological activities have been reported for only 13 species. Thus, 33 species had no phytochemical or pharmacological studies identified in the literature surveyed. Experimental studies have reported antimicrobial, antiparasitic, anti-inflammatory, antioxidant, cytotoxic, and other bioactivities that partially support their traditional medicinal uses. However, no published clinical evidence, including randomized controlled trials, observational studies, or well-documented case series-currently supports the therapeutic efficacy of Kielmeyera preparations in humans. This review provides the first comprehensive and critical synthesis of more than six decades of published research on the taxonomy, ethnobotany, phytochemistry, and pharmacological properties of Kielmeyera species, while highlighting current knowledge gaps and future research priorities.