Antifungal Activity\nof Phloroglucinol Derivatives\nagainst <i>Botrytis cinerea</i> and <i>Monilinia fructicola</i>

Naturally\nderived compounds show promise as treatments\nfor microbial\ninfections. Polyphenols, abundantly found in various plants, fruits,\nand vegetables, are noted for their physiological benefits including\nantimicrobial effects. This study introduced a new set of acylated\nphloroglucinol derivatives, synthesized and tested for their antifungal\nactivity in vitro against seven different pathogenic fungi. The standout\ncompound, 3-methyl-1-(2,4,6-trihydroxyphenyl) butan-1-one (<b>2b</b>), exhibited remarkable fungicidal strength, with EC<sub>50</sub> values of 1.39 μg/mL against Botrytis cinerea and 1.18 μg/mL against Monilinia fructicola, outperforming previously screened phenolic compounds. When tested\nin vivo, <b>2b</b> demonstrated effective antifungal properties,\nwith cure rates of 76.26% for brown rot and 83.35% for gray mold at\na concentration of 200 μg/mL, rivaling the commercial fungicide\nPyrimethanil in its efficacy against B. cinerea. Preliminary research suggests that <b>2b’</b>s antifungal\nmechanism may involve the disruption of spore germination, damage\nto the fungal cell membrane, and leakage of cellular contents. These\nresults indicate that compound <b>2b</b> has excellent fungicidal\nproperties against B. cinerea and holds\npotential as a treatment for gray mold.