Effect of phenolic compounds on growth and ligninolytic enzyme production in Botryosphaeria isolates

Abstract

Botryosphaeria spp. are ligninolytic ascomyceteous fungi that incite many diseases in economically important woody plant species. Four Botryosphaeria isolates, Botryosphaeria rhodina (Lasiodiplodia theobromae), Botryosphaeria obtusa, Botryosphaeria dothidea and Botryosphaeria ribis (Neofusicoccum ribis) were used in this study. Ten naturally occurring phenolic compounds from plants were tested to evaluate their effect on mycelium growth and the production of ligninolytic and pectinolytic enzymes. The effect of phenolic compounds in vitro varied with the Botryosphaeria isolates. Inhibition of mycelium growth was dose-dependent, and varied from 2 to 100% inhibition in the ten phenolic compounds tested except syringic acid, which has no toxic effect on mycelium of Botryosphaeria isolates. A significant decrease in laccase production occurred when Botryosphaeria isolates were grown on phenolic compounds. Benzoic acid significantly inhibited pectinase activity in all isolates. The percent inhibition of pectinase activity in B. dothidea and B. obtusa was significantly increased in the presence of salicylic acid and syringic acid, respectively.