Plant secondary metabolites have made a large contribution to health and human well-being (Roy, 2017), as sources of new bioactive compounds that can be directly used as medicines, or as inspiration for the development of drugs to treat diseases (Newman and Cragg, 2020; Thawabteh et al., 2019). In this context, alkaloids are a class of secondary metabolites that deserve attention due to their bioactivity, such as antimalarial, antibacterial, antiviral, antifungal, and antioxidant, as well as their action on the central nervous system, mainly on chemical transmission (Roy, 2017; Thawabteh et al., 2019). The true alkaloids are structurally characterized by the presence of carbon scaffolds with a nitrogen atom that is derived from an amino acid and is part of a heterocycle. They are classified according to their biosynthetic precursor and heterocyclic ring system (O'Connor, 2010).

The Tabernaemontana genus belongs to the Apocynaceae family, which includes more than 4600 species, classified in 424 genera that are concentrated in five subfamilies: Rauvolfioideae, Apocynoideae, Periplocoideae, Secamonoideae, and Asclepiadoideae (Bhadane et al., 2018). In Brazil, 760 species belonging to 77 genera are registered, more than half of which are endemic species (Flora do Brasil, 2020). Several species are used in traditional medicine to treat stomach pain, diarrhea, fever, skin infections, rheumatism, malaria, and others (Bhadane et al., 2018; Marinho et al., 2016).

Ethnopharmacological reports show that several Tabernaemontana species have been used in Brazil by indigenous people and other communities, including those listed in the Yanomami Pharmacopeia. Moreover, they are considered promising for the discovery of new drugs (Athipornchai, 2018; Silveira et al., 2017), since MIAs might be responsible for a wide range of pharmacological activities, including anticancer, antimalarial, and antiarrhythmic (O'Connor and Maresh, 2006).

Marinho et al. (2016), gathered information on 73 MIAs. The following bioactivities are described in the literature for Brazilian Tabernaemontana species: antimicrobial, antiparasitic, cytotoxic, and anticancer, anti-acetylcholinesterase, anti-butyrylcholinesterase, antiophidic, antioxidant, among others. Herein, 48 additional alkaloids occurring in the Brazilian Tabernaemontana species are described, according to the taxonomical names listed in (Flora do Brasil, 2020). The publication reports experimentally demonstrated biological activities are reported, intending to answer the following questions: Are the Tabernaemontana species occurring in Brazil promising for the discovery of bioactive compounds? Is knowledge on the chemical composition, biological activities, and other information about native or endemic Brazilian Tabernaemontana species being lost as a consequence of deforestation, forest fires, and forest degradation?

Therefore, the aims of this review were to carry out a literature survey of the period from 1960 until June 2023 on Tabernaemontana species occurring in Brazil, as well as to update the existing reviews (Athipornchai, 2018; Danieli and Palmisano, 1986; Marinho et al., 2016; Naidoo et al., 2021; Silveira et al., 2017; Van Beek et al., 1984), in order to provide a foundation for further research on the development of new drugs as well as validation of the traditional use of plants belonging to this taxon. Therefore, the focus of this review was the MIAs occurring in these species and the reported biological activities.