Volatile constituents and chemometric patterns of <i>Myrcia sylvatica</i> (G. Mey) DC. Essential oils: a systematic review of composition and bioactivity

This review compiles the chemical composition, chemometric patterns, and biological activities of essential oils from <i>Myrcia sylvatica</i> (G. Mey.) DC. A total of 216 volatile constituents were reported, mainly hydrocarbon and oxygenated sesquiterpenes, including (<i>E</i>)-caryophyllene, germacrene B, spathulenol, and (<i>Z</i>)-α-trans-bergamotene. Multivariate analyses revealed structured compositional clusters and putative chemotypes, highlighting metabolites responsible for sample differentiation and chemical variability among studies. Because the dataset integrates independent reports obtained under different ecological and methodological conditions, the chemometric results are interpreted as descriptive patterns rather than causal relationships. Reported bioassays indicate antioxidant activity, antibacterial effects against Gram-positive bacteria, and toxicity towards <i>Artemia salina</i>, suggesting pharmacological and agrochemical potential. However, the limited number of studies and methodological heterogeneity restrict comparisons. These findings provide a framework for understanding the chemical diversity of <i>M. sylvatica</i> essential oils and support future integrative studies using standardised sampling and molecular tools to clarify metabolic variability and enable sustainable applications.