Bioactive Potential of Terpenes from Mediterranean Scrub Plants: A Review

The Mediterranean ecosystem is characterized by marked seasonality; it is composed of species such as shrublands that are subjected to high levels of water and thermal stress, making these species an important source of secondary metabolites of significant chemical and ecological interest. In this work, 21 plants were selected from the Mediterranean scrub. These abundant and characteristic representations of the ecosystem produce a total of 197 terpenes. The majority of these are monoterpenes (46.70%), followed by sesquiterpenes (38.07%), with a minority of diterpenes (5.53%) and triterpenes (10.15%). Tetraterpenes accounted for only 0.5% of the total compounds in the species studied, corresponding to only 1%. The major terpenes include 1,8-cineole, terpinen-4-ol, α-terpineol, borneol, camphor, γ-terpinene, limonene, linalool, o-cymene, α-tujene, α-pinene, β-pinene, sabinene, myrcene, β-phellandrene, and β-caryopylene. Species such as Pistacea terebinthus, Rosmarinus officinalis, Cistus ladanifer, Myrtus communis, Lavandula stoecha, and Thymus mastichina contain the most terpenic compounds in their chemical composition. Furthermore, these metabolites are involved in various biological functions, including antimicrobial, antioxidant, neuroprotective, antibacterial, cardiovascular, analgesic, antitumor, and insecticidal activities, among others. Various terpenes present in Mediterranean scrub species, such as 1,8-cineole, α-pinene, limonene, borneol, and terpinen-4-ol, have demonstrated synergistic effects that enhance their antimicrobial, insecticidal, and neuroprotective properties. These interactions between compounds make the natural extracts more effective than they would be individually, increasing their therapeutic and biotechnological value. The synergism among terpenes suggests a promising approach for developing more effective and sustainable phytotherapeutic products.