Comparative archaeometric characterization of recent and historical oak (Quercus spp.) wood

Abstract

The present paper studied the chemical composition of recent and historical oak wood comparing the extractive, holocellulose, α-cellulose, lignin, and ash contents. Comprehensive knowledge of the chemical components in recent and historical oak wood will facilitate the use of conservation agent in the restoration and conservation process of the investigated artifacts. The cyclohexane–ethanol extract of historical oak wood was significantly lower compared to recent wood, which can be explained by the leaching of extractives into the soil. No significant differences in the holocellulose and α-cellulose content of recent and historical oak wood were found. The lignin and the ash contents were significantly higher in the historical samples. The EDX analysis of the ash of historical oak wood showed remarkably higher iron content compared to the recent material. The result indicated the degradation of hemicelluloses in the historical sample. The significant difference in the amount of ash between the samples was explained by sediment materials that have been introduced into the wood from the soil. SEM imaging made these materials clearly visible as depositions in the cell lumens.

Essential Oils as Alternative Biocides for the Preservation of Waterlogged Archaeological Wood

“…Through the action of extracellular enzymes that depolymerase the wood cell walls’ polymers (lignin, cellulose, and hemicelluloses), these microorganisms produce different decay forms that can be grouped in three main categories soft, brown, and white rot [ 1 , 2 , 3 , 4 , 9 , 10 ]. Microbial degradation patterns and cell wall polymers degradation have been widely studied and characterized through microscopic, chemical, and physical analyses [ 11 , 12 , 13 , 14 , 15 , 16 , 17 ].…”

Characterization of Archaeological European White Elm (Ulmus laevis P.) and Black Poplar (Populus nigra L.)

“…Finding has shown that tunneling bacteria (TB) can be present in conditions similar to soft rot, while erosion bacteria (EB) are capable of rotting wood in environments with very low oxygen supply [7]. When wood is submerged underwater or buried in soil, due to the absence of oxygen, the process of co-called wood fossilization is initiated [8]. The rate of wood fossilization and the degradation level of wood polymers increase by the time of deposition [9].…”

“…The rate of wood fossilization and the degradation level of wood polymers increase by the time of deposition [9]. The chemical composition of AW or subfossil wood and the resulting physical and mechanical properties during long-term contact with the soil imply lower cellulose and higher lignin content in fossil wood as compared with FW [8]. Changes in the chemical structure of AW due to environmental elements or application sites have been studied previously [10].…”

“…It is possible for the wood to absorb chemicals such as limestone, through storing it in the lumens. Still, the initial wood extractives would not increase and are more likely to decrease depending on the burial site [8]. Evaluation of archaeological elm (Ulmus sp.)…”

“…It is known that the combination of oxygen and solar radiation rapidly induces oxidation of lignin and hemicelluloses and also depolymerizes the amorphous part of cellulose [16]. The degraded products are water-soluble and will be easily removed from the wood surface by rain, and as a result discoloration of wood surface occurs [8,17,18]. These deterioration mechanisms depend on the conditions that wood is stored and used.…”