Antifungal Activity of Organic Acies and Their Impact on Wood Decay Resistance

Abstract

Organic acids are present in many bio-based chemicals suggested as active ingredients for wood preservative formulations, but their effects in wood have not been studied. However, an understanding of their effect in wood is necessary. The aim of this study was to determine the antifungal and wood-preserving activities in vitro of acetic, formic, and propionic acids against the wood-decaying fungi Coniophora puteana, Rhodonia (Poria) placenta, Gloeophyllum trabeum, and Trametes versicolor. Mixes of these three acids were also tested for possible synergetic effects. All the acids and mixtures showed antifungal activity against the pure cultures of wood-decaying fungi. Propionic acid by itself had the best performance, inhibiting at 1 g/L concentration the growth of all the decay fungi by 99-100%. Despite the antifungal activity of the organic acids, the pine sapwood specimens treated with 3% and 6% acid solutions and exposed to decay by C. puteana and G. trabeum did not differ significantly from the untreated pine. Leaching of the sapwood specimens caused an incremental mass loss of the sapwood specimens. In addition, the leached specimens had a lower mass than the same specimens before the acid impregnation, indicating that they were damaged by the acidic chemicals. The presence and acidity of organic acids in wood-derived bio-based chemicals need to be assessed before they are used as wood preservatives.

Epsilon poly-L-lysine as a novel antifungal agent for sustainable wood protection

“…Together with our preliminary study (unpublished), the minimal inhibitory concentration of EPL against all the fungi was determined to be 3 mg/ml, except for RP , which is 5 mg/ml. Similar research has reported that RP is least sensitive to different organic acids (Barbero-López et al, 2020 ). Our results are also consistent with previous research that EPL treatment causes a dose–response effect on various fungi, such as necrotrophic pathogenic fungi, Sclerotinia sclerotiorum and Botrytis cinerea , and fruit pathogens, Penicillium expansum and Colletotrichum gloeosporioides (Zhou et al, 2021 ; Bai et al, 2022 ; Lv et al, 2022 ).…”

“…Fungal growth in the malt agar substrate was monitored daily for 14 days as it takes different fungi about 7–14 days to fully cover the whole Petri dish, depending on the fungal strains (Barbero-López et al, 2020 ). Photos of each Petri dish due to different EPL treatments, fungal species, and replicates were taken every day using a customized box to minimize the stray light in the photos and to obtain clear pictures ( Supplementary Figure S1 ).…”

Molecular Docking Analysis of Potential Fatty Acid Compounds from Tiger Milk Mushroom (Lignosus rhinocerus (Cooke) Ryvarden) Against Thioesterase Domain of Polyketide Synthase Enzyme in Aspergillus ssp.

“…Hexadecanoic acid-methyl ester functions as an antibacterial [26]. Propionic acid functions as an antimicrobial [27], immunomodulator [28], and antifungal [29]. Palmitic acid functions as an energy source [30], cell structure component [31], and hormone production [32].…”

Evaluation of Chemical and Morphological Properties of Spruce Wood Stored in the Natural Environment

“…These acids emitted from wood have a corrosive effect on exposed exhibits [ 66 , 67 , 68 ]. The study by Barbero-López et al [ 69 ] examines the in vitro antifungal and wood preservative activities of acetic, formic, and propionic acids against the wood decay fungi Coniophora puteana, Rhodonia (Poria) placenta , Gloeophyllum trabeum , and Trametes versicolor .…”