Control efficiency and action mechanisms of camphor leaf extractives on mold resistance of wood

In order to investigate the control efficiency and the action mechanisms of camphor leaf extractives on mold resistance of wood, the cylinder-plate method was used to evaluate the antibacterial effect of different mass fraction of extractives on three common wood molds (Penicillium citrinum, Trichoderma viride and Aspergillus niger). The mold resistance mechanism was estimated using optical microscope and spectrophotometry, and mold resistance efficiency of the wood was evaluated. The results showed that camphor leaf extractives have growth-inhibition effect against Penicillium citrinum, Trichoderma viride and Aspergillus niger through disturbing mycelial structures and growth cycles of three kinds of molds. It was indicated the mass fraction of 12.50% extractives had the best bacteriostatic effect of three kinds of molds, and the corresponding inhibition diameters were 14.2 mm (Penicillium citrinum), 14.9 mm (Trichoderma viride) and 20.1 mm (Aspergillus nige). The minimum mass fractions for mold growth inhibition were 0.50%-1.00% against Penicillium citrinum, 0.50%-1.00% agaist Trichoderma viride, and 0.25% against Aspergillus niger. For different molds, it can make the minimum average infection and reached the maximum control effectiveness by adopting the following approach respectively: the brushing treatment was used against Penicillium citrinum, immersion treatment was used against Trichoderma viride and the mixed molds, and any kind of treatments were used against Aspergillus niger. The immersion treatment was found as the most popular method for mold treatment.