Biocontrol Agents Increase the Specific Rate of Patulin Production by Penicillium expansum but Decrease the Disease and Total Patulin Contamination of Apples

Abstract

Synthetic fungicides are commonly employed for the control of postharvest diseases of fruits. However, due to health concerns about the use of these chemicals, alternative control methods including biocontrol based on antagonistic yeasts are gaining in popularity. In this study, we investigated the effects of two biocontrol yeasts, Rhodotorula mucilaginosa strain 3617 and Rhodotorula kratochvilovae strain LS11, on blue mold and patulin (PAT) contamination caused by Penicillium expansum strains PY and FS7 in artificially inoculated Fuji apples stored at 20°C for 9 days. To correlate the development of the P. expansum strains in yeast-treated and untreated apples with PAT production, we quantified their biomass in the infected fruits using a recently published quantitative real-time polymerase chain reaction method based on specific primers for patF, a gene from P. expansum that is involved in PAT biosynthesis. Both yeasts significantly reduced the disease incidence caused by the two strains of P. expansum up to 5–7 days of incubation, and lowered their biomass and the progression of symptoms up to 9 days. Interestingly, both yeasts strains increased the rate of PAT production (expressed as ng patulin/μg fungal DNA) by the two pathogenic strains. Nevertheless, both biocontrol agents reduced the total PAT contamination, especially in the case of P. expansum strain FS7, the higher PAT producer of the two tested P. expansum strains. Comparing between the yeast strains, R. kratochvilovae LS11 was more effective than R. mucilaginosa 3617 for the control of P. expansum.

Assessment of Detoxification Efficacy of Irradiation on Zearalenone Mycotoxin in Various Fruit Juices by Response Surface Methodology and Elucidation of Its in-vitro Toxicity

“…The fungi predominantly infest cereals, and its by-products (Aldred et al, 2004 ; Mudili et al, 2014 ). However, over last few decades, researchers have ascertained that fruits were as well substantially contaminated with fungi and mycotoxins and pose health at risk (Barkai-Golan and Paster, 2011 ; Juan et al, 2017 ; Škrbić et al, 2017 ; Zheng et al, 2017 ; De Berardis et al, 2018 ; Sandoval-Contreras et al, 2018 ). Mycotoxins can persevere in fruits even once the fungi have been eradicated and could diffuse into healthy portion of fruits (Taniwaki et al, 1992 ; Restani, 2008 ).…”

Recent trends in detecting, controlling, and detoxifying of patulin mycotoxin using biotechnology methods

“…Although biocontrol agents can reduce disease and PAT contamination in fruit, some antagonistic microbes can, unfortunately, increase the amount of PAT produced by each fungus, which the authors of the relevant case study defined as specific mycotoxigenic activity in ng PAT/µg fungal DNA (Zheng et al., 2017). The study was carried out with two biocontrol yeasts, Rhodotorula kratochvilovae strain LS11 and Rhodotorula mucilaginosa strain 3617 used against P. expansum on apples stored at 20°C.…”

“…The study was carried out with two biocontrol yeasts, Rhodotorula kratochvilovae strain LS11 and Rhodotorula mucilaginosa strain 3617 used against P. expansum on apples stored at 20°C. Both microbial biocontrol agents diminished the total PAT contamination but increased the specific rate of production of this mycotoxin (Zheng et al., 2017).…”

Securing fruit production: Opportunities from the elucidation of the molecular mechanisms of postharvest fungal infections

“…The damage and risks caused by pathogenic molds contribute to fruit insecurity. In this context, we can mention pathogens, such as Penicillium expansum , that cause the blue mold disease on different fruit species (Samson & Frisvad, 2004; Zheng et al., 2017) including pome and stone fruits, Penicillium italicum , the blue mold infecting citrus fruit, and the specialized Penicillium digitatum , which produce the green mold disease in citrus fruit (Samson & Frisvad, 2004). A single fruit species may be vulnerable to different molds, with an example being the case of litchi that can be infected by a large number of fungal species, including Alternaria sp., Aspergillus spp., Agrostalagmus sp., Mucor sp., Neurospora sp., Cladosporium sp., Lasiodiplodia theobromae , Colletotrichum spp., Monilia sp.…”