Composition, Antimicrobial, Anti-Inflammatory, and Potential Neuroprotective Activities of Volatile Oils in Solid Wood Boards from Different Tree Ages of Cryptomeria japonica

The wood of <i>Cryptomeria japonica</i> (Japanese cedar or sugi) is widely used in building and adornment. This study aims to identify the composition of the volatile oils (VOs) extracted from <i>C. japonica</i> solid wood boards by gas chromatography-mass spectroscopy, and to investigate their antimicrobial, anti-inflammatory, and potential neuroprotective activities. A total of 58 volatile organic compounds (VOCs) were identified in the VOs from <i>C. japonica</i> solid wood boards with tree ages of 40, 50, and 60 years (VO-40, 50, and 60), with sandaracopimarinol (13.74-17.59%), ferruginol (10.23-11.29%), abieta-7,13-diene (8.20-13.66%), (+)-<i>δ</i>-cadinene (7.15-9.27%), <i>cis</i>-cubenol (4.36-6.36%), and sandaracopimarinal (3.23-6.04%) as major compounds. The VOs exhibited antifungal potential, especially VO-50 against <i>Aspergillus fumigatus</i> (MIC = 0.312 mg/mL), and VO-60 against <i>Gloeophyllum trabeum</i> (MIC = 1.25 mg/mL). However, VOs exhibited weak antibacterial activity (MIC > 10 mg/mL). Additionally, VOs (10 μg/mL) exhibited anti-inflammatory and potential neuroprotective activities, with VO-60 demonstrating the strongest inhibition of NO (25.79% reduction), TNF-<i>α</i> (52.24% reduction), and IL-6 (27.10% reduction) production in lipopolysaccharide-induced RAW264.7 cells, while increasing cell viability by 70.36% and reducing lactate dehydrogenase release by 41.10% in corticosterone-induced PC12 cells. Correlation and docking analyses revealed that sandaracopimarinal, sandaracopimarinol, <i>β</i>-eudesmol, and ferruginol were the potential active compounds. The results demonstrated that the volatile components from <i>C. japonica</i> solid wood boards not only enhance the board's decay resistance, but also exhibit therapeutic potential for inflammatory disorders and neuropathic diseases.