Quantification of microbial growth pattern on growth medium using image processing program and evaluation of antifungal activities of wood vinegar

Abstract

Digitized growth pattern images of wood-rotting fungi Fomitopsis palustris (FOM) and Trametes versicolor (TRA) were used with a video processing program with a new formula to calculate the numerical results of microbial inhibition by an active substance (wood vinegar). First, images of daily growth pattern were collected to generate calibration curves for each fungus. FOM stopped growing in 7 days, whereas TRA stopped growing in 11 days. The calibration curves FOM and TRA showed R2 = 0.9899 and 0.8880, respectively. The new methods allow numerical comparison by adding different concentrations of active components (wood vinegar) to assess the inhibition effect of microbial growth. Using the formula allowed the results of inhibition effect to be collected as numerical data. Through the image data, it was possible to present daily inhibitory efficacy data in detail, numerically. Based on these results, microbial growth pattern could be evaluated.