Schinus molle L. Essential Oil: Chemotypes, Bioactive Compounds, and Pharmaceutical Insights: A Systematic Review

Schinus molle L. Essential Oil (SMEO) displays a rich scientific literature, including preliminary studies on its antimicrobial, antioxidant, and anti-cancer properties. This review seeks to systematically analyze the influence of the chemotype diversity of SMEO on its biological and pharmaceutical applications, with a particular focus on antimicrobial, antioxidant, and anti-cancer activities, and to identify research gaps for effective pharmaceutical exploitation. The article selection process was carried out in June 2025 and focused on the PubMed, Scopus, and MDPI databases, producing 176 articles, of which 51 were selected for this review. The present systematic review included the articles published in English and Spanish, with no limitations on the year of publication; data from patent and symposium abstracts were excluded. A qualitative assessment of the selected articles was carried out, including a TRL (Technology Readiness Level) analysis. The results were summarized using hierarchical cluster analysis and a strategic patent search tree, and were processed into tables, graphs, and a heat map, which enabled discussions and proposals for new research trends to be developed. The chemical composition varies significantly depending on the production area, climatic conditions, and seasonality, but the presence of two prevalent chemotypes is evident, α-phellandrene and sabinene, respectively. Data on antimicrobial, antioxidant, and anti-cancer activity were promising, and some formulation prototypes are available, pointing toward the potential development of pharmaceutical and veterinary products. The use of nanotechnology appears to be crucial for the potential pharmaceutical application of SMEO, but further studies are needed. Specifically, further investigation of the properties of SMEO or its components in wound healing applications could represent a new research trend. This review highlights the state of the art of pharmacological research on SMEO and suggests future research directions with a view to develop formulations suitable for safety and efficacy improvements.