Date of Degree
John J. Lee
In this study ATP photometry and energy charge (EC) measurements were used to detect and quantify fungal biomass in wood. Three species of wood decaying fungi were used: Phanerochaete chrysosporium (white rot), Poria placenta (brown rot), and Chaetomnium globosum (soft rot). The fungi were grown in malt extract broth (MEB) for one month at 25 °C, and sampled at selected intervals to measure the ATP content and the EC of the mycelium. The mycelia were ground and extracted with cold 5% trichloroacetic acid (TCA) for 20 hours. The conversion factors calculated were based upon the EC of the mycelium. When EC was equal, or larger than 0.6, the average ATP was 4.19 nM/mg of dry weight. When EC was below 0.6 the average ATP content of the mycelium was 2.06 nM/mg of dw. Protein and chitin conversion factors were also calculated (protein/dry weight = 48.04 µg/mg of dw, and chitin/dry weight = 41.76 µg/mg of dw). These conversion factors were used to estimate the fungal biomass in wood blocks incubated in vitro with the same species of fungi. The presence of wood in the samples interfered significantly with the protein and chitin assays, but not with the ATP and Energy Charge (EC) measurements. Wood samples were ground in a Wiley mill and extracted with cold 5% trichloroacetic acid for 20 hours. After three months of incubation, birch and loblolly pine lost 16% and 14.73% of their weight when colonized by P. chrysosporium. Their respective biomass of P. chrysosporium on each of these substrates was estimated to be 40 µg and 167 µg. The growth of C. globosum and P. placenta caused negligible weight loss (1.30 and 0.7% respectively), and their respective biomass was only 26xxxg and 10xxxg. This method was applied to assay fungal activity in three statues from the Egyptian collection of the Metropolitan Museum of Art (V Dynasty 2340 BC). The ATP measurements were not different from the background levels. It was concluded that the statues were not infected by fungi at the present time. This ATP assay technique is a rapid effective method to detect fungal biomass in wooden art objects.
Nieto, Fernando, "Measurement of Fungal Biomass in Wooden Art Objects Using ATP Photometry and Energy Charge" (1995). CUNY Academic Works.