The influence of N-acetylglucosamine: Inducing Rhodosporidium paludigenum to enhance the inhibition of Penicillium expansum on pears

Abstract

On the way to impel Rhodosporidium paludigenum to behave like a serviceable and beneficial biocontrol antagonist, it was found that adding different concentrations of N-acetylglucosamine (GlcNAc) during the culture can reduce the incidence of pears caused by Penicillium expansum. 0.1 % GlcNAc is an optimal concentration in the range of 0.001 %–2 %. R. paludigenum, cultivated and gathered from the medium with a final concentration of 0.1 % GlcNAc, declared the best impact on restraint on P. expansum on pears. This inhibitory effect is analogous to the consequence of spore germination experiments in vitro. The R. paludigenum gathered after GlcNAc induction, at the same time, displayed exceptional viability and vigour under different stress conditions, including sodium chloride (NaCl), calcofluor white (CFW), Congo red (CR) and sodium dodecyl sulfate (SDS). The enzyme activity and the relative gene expression levels of some antioxidant-related enzymes in R. paludigenum, including peroxisomal catalase (CAT), thioredoxin reductase (TrxR), glutathione peroxidase (GSH-PX), glutathione reductase (GR) and superoxide dismutase (SOD), were detected to be up-regulated in further testing. At the same time, the reactive oxygen species (ROS) remained at a low status.