Assessing biodeterioration in wood using ATP photometry. Part III. Estimation of the fungal biomass of Phanerochete chrysosporium in decayed wood using ATP and energy charge measurements

Measurements of ATP and Energy Charge (EC) were used to estimate the changes in biomass of P. chrysosporium (white rot), grown in wood blocks. The wood blocks were inoculated with P. chrysosporium and incubated for 3 months at 25°C and 95% RH. The blocks were sampled every month for concentrations of nucleotides (ATP, ADP, and AMP), EC, and weight loss. The possible interference of wood chemicals with the nucleotide assay was studied. EC levels for the three fungi remained below 0.52. The ADP and AMP concentrations were at least 10-fold larger than the ATP. The ATP data were converted into biomass using a conversion factor (ATP/Biomass=0.99 nM/mg of dry weight for EC values below 0.6). P. chrysosporium produced a larger biomass when grown on loblolly (167 μg/g of wood) than on birch (40 μg/g of wood) but the weight loss of the wood was larger in the birch blocks (16% vs 14.73%).