Calocedrus formosana (Cupressaceae) is one of the five precious woods of Taiwan. In this study, we investigated the anti-melanogenic activity of C. formosana wood essential oil (CFEO) and its bioactive components in vitro. Initially, CFEO exhibited strong mushroom tyrosinase activity in the cell-free mushroom tyrosinase assay system with an IC₅₀ value of 2.72 µg/mL. Next, treatment with CFEO significantly as well as dose-dependently reduced a combination of α-melanocyte-stimulating hormone and forskolin (α-MSH-FSK)-induced melanin synthesis in B16-F10 cells. Indeed, 80 μg/mL CFEO completely inhibited melanin production, which is similar to that of control cells. Further studies revealed that treatment with CFEO significantly inhibited melanogenesis regulatory proteins, including TRP-1, TRP-2, and MITF, whereas tyrosinase was unaffected by either α-MSH-FSK or CFEO. In addition, the composition of the CFEO was characterized. The major components of CFEO were α-terpineol (23.47%), shonanic acid (10.45%), terpinen-4-ol (12.23%), thymol (5.3%), piperitone (3.44%), berbenone (2.81%), thujic acid (1.65%), and chaminic acid (0.13%). Among them, shonanic acid (1), thujic acid (2), and chaminic acid (3) were uncommon constitutes in essential oils, which could be the index compounds of CFEO, and the structure of these compounds were confirmed by spectral analysis. Furthermore, we found that thymol is an active ingredient responsible for CFEO’s anti-melanogenic activity. Based on these results, we suggest that CFEO or thymol could be a potential candidate for the development of skin whitening products for cosmetic purposes.

Phellinus noxius is a highly destructive fungus that causes brown root disease in trees, leading to decay and death. In Taiwan, five prized woods—Taiwania cryptomerioides, Calocedrus macrolepis var. formosana, Cunninghamia lanceolata var. konishii, Chamaecyparis formosensis, and Chamaecyparis obtusa var. formosana—are known for their fragrance and durability. This study aims to explore the anti-brown-root-rot-fungus activity of Cunninghamia lanceolata var. konishii (CL) essential oil (CLOL) and its primary components, while also delving into their mechanisms of action and inhibition pathways. The essential oil (CLOL) from CL wood demonstrated significant efficacy against P. noxius, with an inhibitory concentration (IC₅₀) of 37.5 µg/mL. Cedrol, the major component (78.48%) in CLOL, emerged as a potent antifungal agent, surpassing the reference drug triflumizole. Further assays with cedrol revealed a stronger anti-brown-root-disease activity (IC₅₀ = 15.7 µg/mL) than triflumizole (IC₅₀ = 32.1 µg/mL). Scanning electron microscopy showed deformation and rupture of fungal hyphae treated with CLOL and cedrol, indicating damage to the fungal cell membrane. Cedrol-induced oxidative stress in P. noxius was evidenced by increased reactive oxygen species (ROS) levels, leading to DNA fragmentation, mitochondrial membrane potential reduction, and fungal apoptosis through the mitochondrial pathway. Gel electrophoresis confirmed cedrol-induced DNA fragmentation, whereas TUNEL staining demonstrated increased apoptosis with rising cedrol concentrations. Moreover, protein expression analysis revealed cedrol-triggered release of cytochrome c, activation of caspase-9, and subsequent caspase-3 activation, initiating a caspase cascade reaction. This groundbreaking study establishes cedrol as the first compound to induce apoptosis in P. noxius while inhibiting its growth through oxidative stress, an increase in mitochondrial membrane permeability, and activation of the mitochondrial pathway. The findings offer compelling evidence for cedrol’s potential as an effective antifungal agent against the destructive brown root disease caused by P. noxius.

Soil microorganisms play a crucial role in long-term carbon storage, with mycorrhizal fungi being one of the most studied groups due to their ecological importance. These fungi form symbiotic associations with plants, significantly enhancing biomass accumulation and promoting the uptake of atmospheric CO2, thereby increasing plant carbon assimilation. This study was conducted at the Xitou nursery (elevation 1180–1200 m) of the Experimental Forest, National Taiwan University. Taiwan spruce (Picea morrisonicola), one of key native afforestation species in Taiwan, was selected to evaluate the effects of mycorrhizal inoculation on nutrient cycling and carbon dynamics in forest soils. Measurements of soil physicochemical properties, nutrient availability, microbial composition, spruce growth performance, and biochemical traits were carried out to identify potential correlations. Microbial community analysis revealed specific taxa closely linked to improved seedling growth and increased carbon sequestration potential. Observations of phenotypic and biochemical traits across developmental stages indicated that mycorrhizal fungi regulate seedling metabolic activity. Comparative analysis between inoculated and control treatments confirmed that mycorrhizal fungi significantly influence plant physiological responses and enhance soil carbon retention. The findings support the application of native mycorrhizal inoculants in sustainable soil management and reforestation strategies to strengthen the carbon sink function of forest ecosystems.

Ultraviolet B (UVB)-induced photoaging is characterized by oxidative stress, mitochondrial dysfunction, and epidermal barrier impairment. Although extracellular vesicles (EVs) have emerged as bioactive mediators of intercellular signaling, the dermatological relevance of fungal-derived EVs remains poorly understood. In this study, we investigated whether EVs isolated from liquid-cultured Taiwanofungus camphoratus mycelia (TCEVs) protect keratinocytes against UVB-induced damage. TCEVs displayed nanosized vesicular features with a mean particle size of 134.6 ± 4.6 nm and a stable negative surface charge. In HaCaT cells, TCEVs showed no obvious cytotoxicity and increased wound closure. In UVB-exposed keratinocytes, TCEV pretreatment improved cell viability, increased ATP production, reduced intracellular reactive oxygen species accumulation, and improved mitochondrial membrane potential. At the highest tested concentration (10 × 10¹⁰ particles/mL), TCEVs reduced UVB-induced relative ROS levels from 118.65% to 98.2% and increased relative ATP levels from 70.47% to 86.0%. TCEVs also increased the expression of ZO-1, occludin, and Claudin-3 and were associated with increased SIRT1 and p-AMPK expression and partial improvement of PGC-1α. In contrast, Nrf2 and TFAM did not differ significantly from the UVB-irradiated group. These findings support the potential of TCEVs to prevent UVB-induced keratinocyte damage under the present in vitro conditions.