Comparative Bioactivities and Fatty Acid Composition of Pinus koraiensis Leaf Oils Obtained Using Different Extraction Methods

<i>Pinus koraiensis</i> leaves are known for various bioactivities, including anti-cancer, anti-obesity, anti-diabetic, and anti-hyperlipidemic effects. This study aimed to compare the essential oil from <i>P. koraiensis</i> leaves (EPO) and the supercritical-CO₂-extracted oil (SPO) for physicochemical traits, antibacterial and anticancer activities, and anti-inflammatory/antioxidant effects, and profiled fatty acids by means of GC-MS. SPO showed stronger antimicrobial activity than EPO against <i>Streptococcus mutans</i>, whereas EPO was more active against <i>Candida albicans</i>. In HaCaT keratinocytes and THP-1 monocytic cell line, SPO more effectively suppressed LPS-induced ROS and attenuated TNF-α and IL-6 upregulation. Across a panel of human cancer cell lines, SPO exerted greater cytotoxicity, particularly in non-small cell lung, prostate, and colon cancers. GC-MS revealed greater compositional diversity in SPO (16 fatty acids, 10 unique), while linolelaidic acid was detected only in EPO; pentadecenoic acid was abundant in all oils. Collectively, SPO demonstrates broader bioactivity and richer fatty-acid diversity than EPO, supporting its potential as a functional food or medicinal ingredient.