Excellent anti-mildew effect of essential oil impregnation on sliced veneer plybamboo and its anti-mildew mechanism.

Sliced bamboo veneer used as a high-end decoration material is a highly innovative material for the deep processing of bamboo. However, bamboo is rich in starch and small molecular soluble sugars, making it susceptible to mildew infection and limiting the wide application of sliced veneer plybamboo. Spice essential oils are considered green and safe antimildew agents, which are cheap and accessible. The natural phenolic substances in plant essential oil have a good inhibitory effect on bamboo mildew. In this study, three types of spice essential oils (clove essential oil, oregano essential oil, and fennel essential oil) were employed, and their antifungal activity against bamboo mildews was assessed using the Oxford cup method, scanning electron microscopy, transmission electron microscopy, and a micro pH meter. The results demonstrated that the diameters of the Inhibition Zone against four common bamboo mildews (AN, Aspergillus niger; TV, Trichoderma viride; PC, Penicillium citrinum; MM, Mixed Mildews) caused by clove essential oil were 25.68 mm, 23.22 mm, 30.68 mm, and 25.43 mm, respectively. As an explanation, clove essential oil can inhibit or eliminate mildew by damaging and disrupting the cell membrane of the bamboo mildew, leading to significant shrinkage, distortion, surface roughness, formation of holes, or partial structural cracks in the mildew's mycelium. Additionally, it may interfere with and disrupt the pH balance of the intracellular and extracellular fluids within the cell. Furthermore, we also report that sliced veneer plybamboo impregnated with clove essential oil on each layer showed fine inhibition rates of 50%, 75%, 100%, and 25% against AN, TV, PC, and MM, respectively. This research underscores a sustainable approach to mildew prevention, crucial for advancing bamboo's utilization in high-value furniture decor applications.

Importance: Mildew growth in sliced veneer plybamboo poses a significant challenge, particularly in its use for high-end furniture and decor. Traditionally, chemical treatments have been the primary solution though they often raise environmental concerns. Essential oils, with their well-documented antimicrobial properties, have emerged as an important natural and eco-friendly alternative for preventing mildew. These oils inhibit mildew growth effectively while offering a sustainable, non-toxic solution that reduces harm to both the environment and human health. By leveraging essential oils, it becomes possible to extend the lifespan of bamboo products, making them more durable and suitable for broader applications in furniture and decor, all while addressing the ecological limitations of conventional mildew prevention methods.