_________________________________________________________________________________ 19 th International Symposium on Wood, Fibre and Pulping Chemistry, Aug. 28-Sept. 01, 2017. Porto Seguro, BA, Brazil. Comparative Study of Fungal Deterioration in Liquidambar Orientalis Mill Heartwood Extractives *Roderquita K. Moore, Research Chemist, USDA-Forest Service, roderquitamoore@fs.fed.us Doreen Mann, Research Technician, USDA-Forest Service, dmann@fs.fed.us Nural Yilgor, Associate Professor, Istanbul University, yilgorn@istanbul.edu.tr *Corresponding author Abstract A comparative study was done on Liquidambar Orientalis Mill heartwood extractive samples. These extractives were collected from wood decay specimens. The objective of the study was to determine the chemical composition of the extractives remaining after exposure to brown rot fungi Tyromyces Palustris and white rot fungi Trametes Vericolor. All samples were extracted according to TAPPI Standard T-204. Samples were put through two different solvent systems and characterized by analytical techniques for any changes in chemical and morphological properties. The extracted chemicals collected were control 13%, T. versicolor 18% and T. palustris 69%. The polar composition remains higher than the nonpolar composition as is usually observed in hardwoods. Keywords: extractives, deterioration, wood fungi, polar, nonpolar, GC-MS Introduction Biodegradation by fungi will alter the chemical properties of some, if not most, of the general material that makes up tree tissue. So depending on the tree species, the tree anatomy, and the fungi group (white, brown, or soft) that a wood source is exposed to, the relative amounts of molecular structuring could change drastically. 1 It should be possible to determine structural degradation in the form of fungal decay within a tree species by comparing the extractives from a healthy wood sample along with extractives from wood samples exposed to fungi. Comparison of biodegradation from exposure to different fungi is another possibility because of the chemical alterations that are characteristically found to be associated with the fungi species. Extractives are exudates formed by the tree through secondary metabolism after damage or foreign attack by insects or fungi. Extractives form a variety of classes of chemicals according to their origin within the tree. Resin acids are located in the resin canal, fats and waxes are in the ray parenchyma cell and phenolic extracts are in the bark and heartwood. These chemicals are important and necessary for the tree to function. For example, fats are an energy source of the wood cells and terpenoids, while resin acids and phenolics protects the tree against microbial attack. 2,3 Extractives from Liquidambar Orientalis Mill are known for anti-fungal activity and one of the chemicals identified is Benzyl benzoate which has high toxicity against insects. In this study, Liquidambar Orientalis heartwood (LOH) samples were exposed to brown-rot fungi Tyromyces Palustris and white-rot fungi Trametes Vericolor. 1 Liquidambar Orientalis Mill is one of the most important endemic hardwoods, in Turkey. The main objective for this comparative study is to evaluate analytical and quantitative analyses of the changes in LOH extractives due to exposure to white and brown wood decay fungi. Experimental Sample Preparation Researchers in Turkey sent fungi-exposed Liquidambar Orientalis Mill heartwood chips along with a milled offsite untreated control sample. 1 Each of the fungi-treated wood samples were Wiley milled through a 40 mesh sieve. Extraction thimbles were filled with approximately 35.0 g of milled materials. The samples were extracted using the Soxhlet extraction apparatus with a 2 cycle per hour, up to 24 hours solvent turnover rate. The initial solvent composed of 500 mls of 2:1 toluene:ethanol (T:E) mixture was followed by 95% ethanol solvent extraction. Extractives were filtered for any impurities and solvent was evaporated using a rotary evaporator. Extracts were placed in a freezer. 4 Sample Extractions A sample containing 60-100 mg from each solvent extractions was transferred into 5 ml vials. Polar and nonpolar partitions were created from 30 ml total of a 5:1 hexane:chloroform solution. 5 Samples were mixed