Essential Oils from Seed-Depleted Infructescences of Industrial Hemp: Chemical Diversity and Biological Potential

Abstract

Industrial hemp is a chemically rich plant increasingly explored within sustainable production systems aimed at the full utilization of all plant fractions. While hemp inflorescences have been extensively investigated, the biological potential of seed-depleted infructescences remains largely underexplored. This study compared essential oils (EOs) distilled from inflorescences and seed-depleted infructescences of hemp (Cannabis sativa L. cv. Futura 75). Their chemical composition was determined by gas chromatography-mass spectrometry (GC-MS), and their cytotoxicity, hemocompatibility, effects on blood coagulation, and antibacterial activity against a panel of 11 Gram-positive, Gram-negative, and microaerophilic bacterial strains were evaluated. The major EO constituents included alpha-Pinene, (E)-Caryophyllene, Myrcene, alpha-Humulene, Caryophyllene oxide, and Cannabidiol. EOs obtained from seed-depleted infructescences exhibited distinct chemical profiles, low cytotoxicity toward BJ human skin fibroblasts, minimal haemolytic activity, no significant effects on blood coagulation, and, in most cases, stronger antibacterial activity than inflorescence-derived EOs. Particularly high activity was observed against skin- and oral-associated bacteria, including Cutibacterium acnes and Streptococcus species. These findings demonstrate that seed-depleted infructescences represent underutilized post-harvest biomass and a valuable and sustainable source of biologically active EOs, supporting their further investigation for potential pharmaceutical, cosmetic, and oral healthcare applications.