No abstract

This study investigated the efficacy of lauric arginate (LAE) as a potential preservative against wood deteriorating fungi. First, the antifungal properties of LAE against two brown rot fungi, Gloeophyllum trabeum (G.t.) and Rhodonia placenta (R.p.), and two white rot fungi, Trametes versicolor (T.v.) and Irpex lacteus (I.l.) were examined using malt-agar media as substrate. Then the biological resistance of LAE-treated wood specimens (10, 20, and 25 % LAE solutions) was tested following American Wood Protection Association (AWPA) E10 soil-block test procedures. The in vitro study showed LAE actively inhibited the growth of all the fungi tested compared to growth in control plates but there were no considerable changes observed in the morphology of fungi hyphae. Wood impregnated with LAE showed increased weight percent gain as a function of treatment concentration. Characterization of LAE-treated wood on a thermogravimetric analyzer showed LAE shifted the thermal degradation temperatures to lower stages but did not significantly improve the thermal stability of the treated specimen. LAE in wood significantly suppressed fungus growth, leading to decreased mass loss but it also leached out from wood specimens during fungi exposure.

Conservation of historic timber structures is of great importance for cultural inheritance and community identity promotion. However, most of the current methods available for ancient architecture protection significantly affect their original appearance and aesthetic value and finding wood elements that are similar to the ones in existing historic timber structures is not easy. Here we report a simple and effective method to archaize wood, Castanopsis sclerophylla, by ferric chloride (FeCl 3 ) treatment without significantly affecting its mechanical properties and durability. The lightness and the color indexes of treated wood are similar to the ancient wood sample. The mechanical properties of FeCl 3 treated wood are not statistically different from the control. Our durability testing results indicated that FeCl 3 treated wood has good decay resistance against Irpex lacteus and Trametes versicolor with a mass loss of less than 10 %. This study provides a convenient method for the restoration and protection of ancient buildings.