Distribution and bioactivities of tirucallane-type triterpenoids from Meliaceae family

Tirucallane-type triterpenoids are one of the most structurally diverse classes of secondary metabolites in Meliaceae family, which is predominantly distributed across tropical and subtropical regions. A total of 373 tirucallane derivatives have been reported between 1967 and 2025, from 48 species belonging to 17 genera. These compounds were isolated from different plant parts, including bark, stem bark, roots, leaves, fruits, twigs, seeds, and aerial tissues. Therefore, this review aims to integrate current reports on tirucallane-type triterpenoids from 17 Meliaceae genera, emphasizing structural complexity, taxonomic occurrence, and pharmacological relevance to guide future chemotaxonomic and drug discovery efforts. Literature collection was performed through Google Scholar, Reaxys, PubMed, and SciFinder. The results showed that based on the structural characteristics, tirucallane derivatives were categorized into intact, seco, heteroatom-substituted, degraded, and highly rearranged, with the intact subgroup being the most abundant. Furthermore, tirucallane derivatives have a broad spectrum of biological properties, including cytotoxic, antimicrobial, antiplasmodial, antidiabetic, anti-inflammatory, immunomodulatory, FXR agonistic, and insecticidal effects, indicating significant potential therapeutic value. Among the reported compounds, laxiracemosin E (361) showed the strongest anticancer potential with IC₅₀ = 1.5 µM, while aphanamgrandin C (372), aphanamgrandin D (373), and dubione B (227) demonstrated potent antibacterial activity (MIC = 1.57-3.13 µg/mL). Hispidol A (2) indicated remarkable antiplasmodial activity (IC₅₀ = 2.45 µM), while meliasenin G (64), phellochin (66), and methyl angolensate (343) were identified as promising α-glucosidase inhibitors (IC₅₀ = 6.1 µM). In conclusion, tirucallane triterpenoids from Meliaceae offer an outstanding structural platform for future drug discovery and bioactivity optimization.