Content Analysis and Antimicrobial Activity of Pyrolysis Liquid Obtained From Oak Residue (Quercus Sp.)

Abstract

The search for organic pesticides continues due to the adverse effects of chemical pesticides used against plant pathogens such as bacteria, and fungi. The evaluation of agricultural and forestry residues within this framework is of vital importance from many perspectives. This study was conducted to determine the activity of pyrolysis liquid (PL) prepared at different concentrations ranging from 1% to 25%, v/v against certain plant pathogenic bacteria and fungi. The PL was obtained from a company that produces charcoal through carbonization at temperatures ranging from 100 to 550 °C. The study was carried out in vitro under a Randomized Plot Design with four replications. The content analysis of PL was determined using solid-phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS). The detection of antifungal activity was performed using the Poisoned Food Method on Malt Extract Agar, while antibacterial activity was determined using the Agar Well Diffusion Method on Mueller-Hinton Agar. Statistical analyses of the obtained datasets (factorial ANOVA) indicated that both the statistical significance of the concentration (P=0.001) and its practical importance (effect size=0.9953) were significant. It was determined that concentrations of PL at 2% and above (v/v) completely inhibited fungi populations. It is suggested that the PL used in this study has potential antifungal activity and can be utilized for various purposes, particularly in plant protection activities. © 2025, ALÖKI Kft., Budapest, Hungary.