Ethyl pyruvate (EP) suppressed post‐harvest blue mold of sweet cherry fruit by inhibiting the growth of Penicillium oxalicum

Abstract

BACKGROUND The shelf‐life of fresh sweet cherry is relatively short due to fungal decay during post‐harvest storage. To investigate the effect and the mechanism of action of ethyl pyruvate (EP) against blue mold of sweet cherry fruit caused by Penicillium oxalicum, the spores were treated with 25 mg L−1 EP. The spore germination rate of P. oxalicum, the integrities of the cell wall and plasma membrane, reactive oxygen species (ROS) and malondialdehyde (MDA) were evaluated. RESULTS EP treatment significantly suppressed post‐harvest blue mold of sweet cherry fruit. We found that the treatment of 25 mg L−1 EP significantly suppressed blue mold of post‐harvest sweet cherry fruit by directly inhibiting germination and the mycelial growth of P. oxalicum. After co‐inoculation with EP for 30 min, the spore germination rate of P. oxalicum was reduced by 83.5%. In addition, the pH of the EP solution was found to affect its antimicrobial activity. After treatment with EP, the cell surface structures of the spores of P. oxalicum were much more incomplete, and higher ROS and MDA values were recorded in the spores. CONCLUSIONS The results suggested that EP treatment destroyed the integrities of the cell surface structures and caused oxidative damage of the spores of P. oxalicum. © 2019 Society of Chemical Industry

Isolation, structural characterization and sporicidal properties of Baelezcin A, a novel cyclic lipopeptide from Bacillus velezensis SJ100083 against gray mold

“…Cherry preservation assay referenced by previous studies with a few modifications. 30 The selected perfect cherry fruit was soaked in 2% sodium hypochlorite (NaClO, v/v, Macklin, Shanghai, China) solution for 30 s. Then the fruit was rinsed three times with sterilized distilled water (DW) to remove the NaClO solution and airdried to use. Next, a sterile syringe was used to prick a 5 mm deep wound in the middle of each fruit.…”

“…The amount of reactive oxygen species (ROS) within Botrytis cinerea spores was determined as described previously, but with some modifications. 30 Spores of Botrytis cinerea (10 6 CFU mL −1 ) were incubated in PDB containing 0 or 25 mg L −1 Baelezcin A for 0-60 min. Centrifugally collected spores were washed in phosphate-buffered saline (PBS, 10 mM, pH 7.4) twice.…”

Identification of the Causal Agent of Aqueous Spot Disease of Sweet Cherries (Prunus avium L.) from the Jerte Valley (Cáceres, Spain)

“…The occurrence of brown rot in sweet cherries has been widely documented and can be caused by Monilia fructicola [7], Monilia fructigena [8], and Monilia laxa [9]. Different species of Penicillium have been responsible for cherry spoilage, such as Penicillium expansum [10], Penicillium crustosum [11], and Penicillium oxalicum [12]. Botrytis cinerea [13,14], Alternaria alternata [15], and Rhizopus stolonifer [16] are the other pathogens reported as rot causing agents in sweet cherries.…”