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BACKGROUND: Fresh ginseng is typically accompanied by soil after harvest, leading to contamination with harmful fungi during storage and distribution. In this study, we investigated the incidence of fungal contamination in fresh ginseng (5–6 years old) purchased from 22 different stores in Geumsan, Korea. RESULTS: The incidence of fungal contamination in the samples was 67.4–111.5%. Fusarium solani was the most abundant species in the head (38.5%) and fine root (19.3%) parts of the ginseng samples, whereas F. oxysporum was the most abundant in the main root (22.0%) part. We isolated Aspergillus, Fusarium and Penicillium spp. (total number of isolates: 395) from the ginseng samples, and 138 isolates were identified using phylogenetic analysis. Polymerase chain reaction‐based screening of 65 mycotoxin‐producing species revealed that two P. expansum isolates were positive for citrinin and/or patulin, and five F. oxysporum isolates were positive for fumonisin biosynthesis gene. One P. expansum isolate produced 738.0 mg kg−1 patulin, and the other produced 10.4 mg kg−1 citrinin and 12.0 mg kg−1 patulin on potato dextrose agar (PDA) medium. Among the 47 representative F. oxysporum isolates, 43 (91.5%) produced beauvericin (0.1–15.4 mg kg−1) and four of them (8.5%) produced enniatin B and enniatin B1 (0.1–1.8 mg kg−1) as well. However, none of these toxins was detected in fresh ginseng samples. CONCLUSION: Fusarium solani and F. oxysporum were the most abundant species in fresh ginseng samples. Most F. oxysporum (43) and P. expansum (2) strains isolated from fresh ginseng produced beauvericin and enniatins (B and B1), and patulin or citrinin, respectively, on PDA medium. This is the first report of the mycotoxigenic potential of P. expansum and F. oxysporum strains isolated from fresh ginseng. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Blue mold caused by Penicillium expansum infection results in severe postharvest deterioration of apples. Salicylic acid (SA) is an effective elicitor of fruit resistance. However, the metabolic mechanism of P. expansum infection of apples and the SA-mediated metabolic responses are still unknown. In this study, the metabolite changes during P. expansum infection of apples and SA-mediated disease resistance were explored by performing ultra-performance liquid chromatography and quadrupole-time-of-flight mass spectrometry. A total of 472 different metabolites were identified between the five groups of sample comparisons, and the correlated metabolic pathways were revealed by bioinformatics analysis. The upregulation of the tricarboxylic acid (TCA) cycle, galactose metabolism, and starch and sucrose metabolism reflected energy conversion for P. expansum invasion and fruit disease resistance. Changes in glyoxylate and dicarboxylate metabolism and carbapenem biosynthesis reflected the biosynthesis of virulence factors and secondary metabolites for fungal infection. Metabolic pathways related to apple natural disease resistance mainly included the upregulation of secondary metabolite biosynthesis and sphingolipid metabolism. SA promoted the TCA cycle, reactive oxygen metabolism, and secondary metabolite biosynthesis of apples for disease resistance. This study revealed the metabolic pathways of P. expansum infection of apples and SA-mediated disease resistance, which helps to improve the understanding of the pathogenic mechanism and disease control. [ABSTRACT FROM AUTHOR]

[Display omitted] Penicillium expansum is a harmful plant fungal pathogen that causes blue mold disease and produces mycotoxin patulin, leading to huge economic losses and food safety hazard. Set1 associated complex Set1/COMPASS deposits the methylation at lysine 4 of histone H3, which is associated with gene expression in diverse biological processes of fungi. However, the function and underlying mechanisms of Set1/COMPASS are poorly defined in P. expansum. The study aimed to identify Set1/COMPASS and investigate its regulation mechanisms on growth, pathogenicity, and patulin biosynthesis of P. expansum. Analyses of phylogenetic relationship, conserved structural domain, and gene deletion were used to identify components of Set1/COMPASS. Phenotype analysis and stress tolerance test of gene deletion mutants were conducted to analyze the function of these components. Yeast two-hybrid, Co-Immunoprecipitation (Co-IP), and point mutation were performed to verify the protein interaction. Western blot was conducted for detection of H3K4 methylation levels. P. expansum owns six components of Set1/COMPASS besides PeSet1. Absence of each component resulted in reduction of H3K4 methylation levels and impaired growth, pathogenicity, and patulin biosynthesis, as well as altered stress responses of P. expansum. One component PeBre2p was found to interact with the conserved global regulator PeVelB (Ve lvet L ike protein B) at Asp294 of PeBre2p. This interaction affected fungal growth and utilization of fructose, lactose, glycine, and proline in P. expansum. This study revealed the important roles of Set1/COMPASS in P. expansum and clarified for the first time the combined regulation of PeBre2p and PeVelB in fungal growth and nutrition utilization. These results will provide potential targets for the control of blue mold disease. [ABSTRACT FROM AUTHOR]

Penicillium expansum is the predominant causal agent causing blue mold in postharvest fresh Codonopsis pilosula during storage. The pathogen reduces the yield and affects the quality of C. pilosula and even generates patulin, threatening human health. In this study, postharvest fresh, healthy C. pilosula was sprayed with P. expansum, and the control effect of ozone on postharvest diseases of C. pilosula was studied, and the effect of ozone on the contents in the main active ingredients of C. pilosula was compared; finally, the effect of ozone on reactive oxygen species (ROS) metabolism in C. pilosula was analyzed. The results showed that 2 mg L−1 ozone application significantly inhibited the occurrence of postharvest blue mold caused by P. expansum, reduced weight loss rate, controlled the accumulation of patulin and maintained the contents of the main active components in C. pilosula. The study will provide a theoretical basis for ozone treatment to control the occurrence of postharvest diseases of C. pilosula. [ABSTRACT FROM AUTHOR]

Patulin is a secondary metabolite primarily synthesized by the fungus Penicillium expansum, which is responsible for blue mold disease on apples. The latter are highly susceptible to fungal infection in the postharvest stages. Apples destined to produce compotes are processed throughout the year, which implies that long periods of storage are required under controlled atmospheres. P. expansum is capable of infecting apples throughout the whole process, and patulin can be detected in the end-product. In the present study, 455 apples (organically and conventionally grown), destined to produce compotes, of the variety "Golden Delicious" were sampled at multiple postharvest steps. The apple samples were analyzed for their patulin content and P. expansum was quantified using real-time PCR. The patulin results showed no significant differences between the two cultivation techniques; however, two critical control points were identified: the long-term storage and the deck storage of apples at ambient temperature before transport. Additionally, alterations in the epiphytic microbiota of both fungi and bacteria throughout various steps were investigated through the application of a metabarcoding approach. The alpha and beta diversity analysis highlighted the effect of long-term storage, causing an increase in the bacterial and fungal diversity on apples, and showed significant differences in the microbial communities during the different postharvest steps. The different network analyses demonstrated intra-species relationships. Multiple pairs of fungal and bacterial competitive relationships were observed. Positive interactions were also observed between P. expansum and multiple fungal and bacterial species. These network analyses provide a basis for further fungal and bacterial interaction analyses for fruit disease biocontrol. [ABSTRACT FROM AUTHOR]

Blue mold, a postharvest disease of pome fruits, is caused by the filamentous fungus Penicillium expansum. In addition to the economic losses caused by P. expansum, food safety can be compromised, as this pathogen is mycotoxigenic. In this study, forward and reverse genetic approaches were used to identify genes involved in blue mold infection in apple fruits. For this, we generated a random T-DNA insertional mutant library. A total of 448 transformants were generated and screened for the reduced decay phenotype on apples. Of these mutants, six (T-193, T-275, T-434, T-588, T-625, and T-711) were selected for continued studies and five unique genes were identified of interest. In addition, two deletion mutants (Δt-625 and Δt-588) and a knockdown strain (t-434KD) were generated for three loci. Data show that the ∆t-588 mutant phenocopied the T-DNA insertion mutant and had virulence penalties during apple fruit decay. We hypothesize that this locus encodes a glyoxalase due to bioinformatic predictions, thus contributing to reduced colony diameter when grown in methylglyoxal (MG). This work presents novel members of signaling networks and additional genetic factors that regulate fungal virulence in the blue mold fungus during apple fruit decay. [ABSTRACT FROM AUTHOR]

Penicillium expansum is the most popular post-harvest pathogen and causes blue mold disease in pome fruit and leads to significant economic losses worldwide every year. However, the fundamental regulation mechanisms of growth in P. expansum are unclear. Recently, non-coding RNAs (ncRNAs) have attracted more attention due to critical roles in normalizing gene expression and maintaining cellular genotypes in organisms. However, the research related to ncRNAs in P. expansum have not been reported. Therefore, to provide an overview of ncRNAs on composition, distribution, expression changes, and potential targets in the growth process, a comparative transcriptomic analysis was performed on spores and mycelia of P. expansum in the present study. A total of 2595 novel mRNAs, 3362 long non-coding RNAs (lncRNAs), 10 novel microRNAs (miRNAs), 86 novel small interfering RNAs (siRNAs), and 11,238 circular RNAs (circRNAs) were predicted and quantified. Of these, 1482 novel mRNAs, 5987 known mRNAs, 2047 lncRNAs, 40 miRNAs, 38 novel siRNAs, and 9235 circRNAs were differentially expressed (DE) in response to the different development stages. Afterward, the involved functions and pathways of DE RNAs were revealed via Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) database enrichment analysis. The interaction networks between mRNAs, lncRNAs, and miRNAs were also predicted based on their correlation coefficient of expression profiles. Among them, it was found that miR168 family members may play important roles in fungal growth due to their central location in the network. These findings will contribute to a better understanding on regulation machinery at the RNA level on fungal growth and provide a theoretical basis to develop novel control strategies against P. expansum. [ABSTRACT FROM AUTHOR]

β-1,3-glucanase plays an important role in the biodegradation, reconstruction, and development of β-1,3-glucan. An endo-β-1,3-glucanase which was encoded by PeBgl1 was expressed, purified and characterized from Penicillium expansum for the first time. The PeBgl1 gene was amplified and transformed into the competent cells of E. coli Rosetta strain with the help of the pET-30a cloning vector. The recombinant protein PeBgl1 was expressed successfully at the induction conditions of 0.8 mmol/L IPTG at 16 °C for 16 h and then was purified by nickel ion affinity chromatography. The optimum reaction temperature of PeBgl1 was 55 °C and it had maximal activity at pH 6.0 according to the enzymatic analysis. Na2HPO4-NaH2PO4 buffer (pH 6.0) and NaCl have inhibitory and enhancing effects on the enzyme activities, respectively. SDS, TritonX-100 and some metal ions (Mg2+, Ca2+, Ba2+, Cu2+, and Zn2+) have an inhibitory effect on the enzyme activity. The results showed that PeBgl1 protein has good enzyme activity at 50–60 °C and at pH 5.0–9.0, and it is not a metal dependent enzyme, which makes it robust for storage and transportation, ultimately holding great promise in green biotechnology and biorefining. [ABSTRACT FROM AUTHOR]

Penicillium expansum is a main producer of patulin that causes severe postharvest decay and food safety issues in the fruit industry. Development, pathogenicity, and patulin production of P. expansum are strongly influenced by the PacC-pH signaling pathway. Global transcription factor PacC regulates various fungal biological processes through a complicated molecular network. In the present study, three Ena family genes (PeEnas), PeEnaA, PeEnaB, and PeEnaC, as important downstream targets of PePacC, were identified in P. expansum. Deletion of PeEnaA, PeEnaB, and PeEnaC showed little effect on mycelial growth under alkaline or high salinity conditions, but double and triple deletion of these genes impaired the virulence of P. expansum on apple fruit. Notably, patulin biosynthesis of P. expansum was distinctly inhibited in the deletion mutants of PeEnas. PeEnas regulated expressions of the patulin gene cluster, AP1, CreA, Sge1, and Hog1 at the transcriptional level and played roles in maintaining membrane potential. Overexpression of PeEnaC in ΔPePacC restored the patulin production defect of ΔPePacC. Our results indicated that, as downstream targets of PePacC, the PeEna family proteins play a crucial role in patulin biosynthesis in P. expansum. [ABSTRACT FROM AUTHOR]

Communesins are rare alkaloids isolated from fungi of the genus Penicillium. In this work, the extract of a marine‐derived Penicillium expansum strain was studied using targeted molecular networking approach allowing to detect 65 communesins including 55 new ones. A fragmentation pattern for dimethylvinyl communesins was established and a script was implemented allowing to predict the structure and map all communesins in a global molecular network. A semisynthetic strategy was carried out to obtain some minor congeners from the two isolated communesins A and B. Nine communesins were then synthetised: two of them were already described as produced by the studied strain; four are new natural products which occurrence in the extracts was confirmed; three are new semi‐synthetic analogues never described so far. These communesins were evaluated for their cytotoxicity on two human cancer cell lines KB and MCF‐7 leading to a preliminary study of their structure‐activity relationships. [ABSTRACT FROM AUTHOR]

Onion is one of the most important salad and vegetable plants in all parts of Pakistan. Onions in storage are being affected by different types of diseases, but Blue Mold of Onions is one of the most important detrimental post-harvest diseases of onions. The research was conducted in the Plant Pathology Laboratory at Sindh Agriculture University, Tando Jam, to manage Penicillium expansum by applying different Botanical extracts, Viz., Caramon, Garlic and Neem. The efficacy of all three botanicals was tested on storage onion with three replications and data was collected at four days' intervals. After statistical analysis, it was observed that all three botanicals cause significant reductions in the rot severity of onion in storage: among the three botanicals, Neem was found most effective in reducing rot severity, followed by garlic and caramon. [ABSTRACT FROM AUTHOR]

One of the most significant challenges associated with postharvest apple deterioration is the blue mold caused by Penicillium expansum, which leads to considerable economic losses to apple production industries. Apple fruits are susceptible to mold infection owing to their high nutrient and water content, and current physical control methods can delay but cannot completely inhibit P. expansum growth. Biological control methods present promising alternatives; however, they are not always cost effective and have application restrictions. P. expansum infection not only enhances disease pathogenicity, but also inhibits the expression of host-related defense genes. The implementation of new ways to investigate and control P. expansum are expected with the advent of omics technology. Advances in these techniques, together with molecular biology approaches such as targeted gene deletion and whole genome sequencing, will lead to a better understanding of the P. expansum infectious machinery. Here, we review the progress of research on the blue mold disease caused by P. expansum in apples, including physiological and molecular infection mechanisms, as well as various methods to control this common plant pathogen. [ABSTRACT FROM AUTHOR]

erg4 is a key gene for ergosterol biosynthesis in filamentous fungi, but its function in Penicillium expansum remains unknown. Our results showed that P. expansum contains three erg4 genes, including erg4A, erg4B and erg4C. The expression levels of the three genes showed differences in the wild-type (WT) strain, and the expression level of erg4B was the highest, followed by erg4C. Deletion of erg4A, erg4B or erg4C in the WT strain revealed functional redundancy between them. Compared to the WT strain, erg4A, erg4B or erg4C knockout mutants reduced ergosterol levels, with erg4B deletion having the greatest effect. Furthermore, deletion of the three genes reduced sporulation of the strain, and Δerg4B and Δerg4C mutants showed defective spore morphology. In addition, Δerg4B and Δerg4C mutants were found to be more sensitive to cell wall integrity and oxidative stress. However, deletion of erg4A, erg4B or erg4C had no significant effect on colony diameter, spore germination rate, conidiophore structure of P. expansum or pathogenicity to apple fruit. Taken together, erg4A, erg4B and erg4C have redundant functions and are all involved in ergosterol synthesis and sporulation in P. expansum. In addition, erg4B and erg4C contribute to spore morphogenesis, cell wall integrity and response to oxidative stress in P. expansum. [ABSTRACT FROM AUTHOR]

Today, chemical agents are used to control post -harvest lesions of Fruits but its harmful effects could be considered as an important factor in reducing shelf life. Recently aloe vera has played an important role in maintaining the quality and health of fruits as well as controlling the pathogenic fungi. Aloe vera coating was used in different concentrations of gel (100,75,50,25%) during 36 days of storage at 4 degrees Celsius. Microbial stability, physicochemical properties (weight loss,tissue stiffness, pH, Soluble solids) and color sensory properties pears coated with aloe vera gel were evaluated after 36 days of storage compared to the control as well as the effect of aqueous and ethanolic extracts of aloe vera on two species of fungi penicillium expansum and aspergillus Niger were investigated. The results showed that the growth of microorganism has significantly been delayed by aloe vera gel coating and there was a reduction in weight loss compared to control and this coating to maintain better rigidity and reduction of soluble solids and it had a significant effect on the pH of the treatments. And had no significant effect on the sensory properties of color in different treatments compared to the control. Also,aqueous and ethanolic extract of aloe Vera has a growth in habiting effect on these fungi. As a result,coating aloe Vera gel on pear fruit increases its shelf life. [ABSTRACT FROM AUTHOR]

Blue mold decay caused by Penicillium expansum is one of the most important postharvest diseases of grapes, leading to considerable economic losses. Regarding the increasing demand for pesticide-free foods, this study aimed to find potential yeast strains for biological control of blue mold on table grapes. A total of 50 yeast strains were screened for antagonistic activity against P. expansum using the dual culture method and six strains significantly inhibited the fungal growth. All six yeast strains (Coniochaeta euphorbiae , Auerobasidium mangrovei , Tranzscheliella sp., Geotrichum candidum , Basidioascus persicus , and Cryptococcus podzolicus) reduced the fungal growth (29.6–85.0%) and the decay degree of wounded grape berries inoculated with P. expansum while G. candidum was found to be the most efficient biocontrol agent. On the basis of antagonistic activity, the strains were further characterized by in vitro assays involving inhibition of conidial germination, production of volatile compounds, iron competition, production of hydrolytic enzymes, biofilm-forming capacity, and exhibited three or more putative mechanisms. To our knowledge, the yeasts are reported for the first time as potential biocontrol agents against the blue mold of grapes but more study is required to evaluate their efficiency related to field application. [Display omitted] • Fifty yeast strains were screened for antagonistic activity against P. expansum in vitro. • Six novel yeast strains with biocontrol activity against P. expansum on grapes were introduced. • Treatment of grapes with G. candidum resulted in an 85% reduction in P. expansum growth. • G. candidum showed higher biofilm-forming capacity in vitro than the other strains. [ABSTRACT FROM AUTHOR]

Blue mold, caused by Penicillium expansum, is the most destructive fungal disease of apples and causes great losses during the post-harvest storage of the fruit. Although some apple cultivars are resistant to P. expansum, there has been little information on the molecular mechanism of resistance. In this study, differential proteomic analysis was performed on apple samples infected and uninfected with P. expansum. Parallel reaction monitoring (PRM) technology was used to target and verify the expression of candidate proteins. The label-free technique identified 343 differentially expressed proteins, which were mainly associated with defense responses, metal ion binding, stress responses, and oxidative phosphorylation. The differential expression of enzymes related to reactive oxygen species (ROS) synthesis and scavenging, the activation of defense-related metabolic pathways, and the further production of pathogenesis-related proteins (PR proteins) during P. expansum infection in apples, and direct resistance to pathogen invasion were determined. This study reveals the mechanisms of apple response at the proteomic level with 9 h of P. expansum infection. [ABSTRACT FROM AUTHOR]

Salicylic acid (SA) is a natural inducer of disease resistance in fruit, but its application in the food industry is limited due to low water solubility. Here, SA was encapsulated in β-cyclodextrin (β-CD) via the host–guest inclusion complexation method, and the efficacy of SA microcapsules (SAM) against blue mold caused by Penicillium expansum in postharvest apple fruit was elucidated. It was observed that SAM was the most effective in inhibiting the mycelial growth of P. expansum in vitro. SAM was also superior to SA for control of blue mold under in vivo conditions. Enzyme activity analysis revealed that both SA and SAM enhanced the activities of superoxide dismutase (SOD) and phenylalanine ammonia lyase (PAL) in apple fruit, whereas SAM led to higher SOD activities than SA. Total phenolic contents in the SAM group were higher than those in the SA group at the early stage of storage. SAM also improved fruit quality by retarding firmness loss and maintaining higher total soluble solids (TSS) contents. These findings indicate that microcapsules can serve as a promising formulation to load SA for increasing P. expansum inhibition activity and improving quality attributes in apple fruit. [ABSTRACT FROM AUTHOR]

Deoxyacetyl-donacinoic acid B (1), a new bergamotane-type sesquiterpenoid, was isolated from the rice solid fermentation of Penicillium expansum GY618. The structure of compound 1 was well established by the detailed interpretation of NMR and HR-ESI-MS data, as well as ECD measurement powered by molecular calculation. The antibacterial activities of compound 1 were evaluated. [ABSTRACT FROM AUTHOR]

Penicillium expansum is one of the primary pathogens causing postharvest blue mold of pears, which leads to the spoiling of pulp and produces patulin, endangering food security. Mitogen-activated protein kinase (MAPK) signaling pathway regulates the growth and development, cell wall integrity, and pathogenicity of fungi. Mitogen-activated protein kinase kinase (MKK) in the MAPK signaling pathway has been reflected to be associated with fungal cell wall integrity. Nevertheless, the pivotal function of MKK in the process of P. expansum infection remained unexplored. In this study, MKK was knocked out and repaired by the Agrobacterium -mediated homologous recombination technology to explore the function of MKK in P. expansum infection process. It has been found that the deletion of MKK induces morphological changes in the mutant strain and delayed mycelium and spore growth. Further studies showed that the mutant strain was susceptible to cell wall interference compounds and showed a significant decrease in decay diameters and virulence during the infection of the pears. RT-qPCR analysis showed that the deletion of MKK affected the relative expression levels of its upstream and downstream genes. Our results suggest that MKK is essential in the growth and development, cell wall integrity, pathogenicity, and toxigenic capacity of P. expansum. • MAP kinase MKK negatively affects the growth of Penicillium expansum. • The knockout of MKK reduces the ability of P. expansum to infect the pears. • The knockout of MKK diminishes the toxigenic capacity of P. expansum infecting pears. [ABSTRACT FROM AUTHOR]

Apples (Malus domestica) are one of the most consumed fruits globally. It is a relevant crop in Argentina and Spain, and one of the main fruits for export and industrialization in these countries. Quality control of apples, fundamentally in the postharvest stage, is critical to prevent fungal diseases. The blue mould, caused by Penicillium expansum , is responsible for great economic losses due to the deterioration of the fruit and mycotoxin production. Many studies have characterized this pathogen; however, little is known about the differences between populations from distant geographical origins. The objective of the present study was to characterize two P. expansum populations, from Argentina and Spain, through morphological, metabolomic and molecular approaches, and to evaluate the existence of differences related to their geographical source. A total of 103 isolates, 53 from Argentina and 50 from Spain were studied. Their morphological features were consistent with the species description. The secondary metabolite profiles revealed low chemical diversity. All 103 isolates shared the production of 13 compounds, namely andrastins, aurantioclavine, chaetoglobosins, communesins, expansolides, roquefortine C and patulin. Penostatins and citrinin were produced by 102 and 101 isolates, respectively. A region of the β-tubulin gene was selected to analyse the diversity of the P. expansum isolates. No substantial differences were observed between isolates of different geographical origins through morphology, patulin accumulation, secondary metabolite profiles and phylogenetic analysis. However, the analysis of polymorphisms revealed 29 haplotypes with a relative separation between isolates of both populations; 13 haplotypes contained Argentinean isolates, while Spanish isolates were separated into 16 haplotypes. The diversity indices of Shannon (H'= 2.075; H'= 2.402) and Simpson (Si D = 0.850; Si D = 0.895) for isolates from Argentina and Spain, respectively, indicated that the diversity of P. expansum is greater in Spain than in Argentina. This distribution could be explained both by the existence of haplotype exchange between both countries, with the ancestral haplotypes originating in Spain, and the subsequent adaptation to the environmental conditions or apples varieties grown in each region. • Penicillium expansum populations from Argentinean and Spanish apples were compared. • P. expansum populations showed low secondary metabolite diversity. • Phylogenetic analyses did not allow establishing evolutionary relationships. • Relative separation was revealed by analysis of polymorphisms in the β-tub fragment. • A significant geographical genetic structure was found in the populations. [ABSTRACT FROM AUTHOR]

Penicillium digitatum and Penicillium expansum are plant pathogenic fungi that cause the green and blue mold diseases, respectively, leading to serious postharvest economic losses worldwide. Moreover, P. expansum can produce mycotoxins, which are hazardous compounds to human and animal health. The development of tools that allow multiple and precise genetic manipulation of these species is crucial for the functional characterization of their genes. In this sense, CRISPR/Cas9 represents an excellent opportunity for genome editing due to its efficiency, accuracy and versatility. In this study, we developed protoplast generation and transformation protocols and applied them to implement the CRISPR/Cas9 technology in both species for the first time. For this, we used a self-replicative, recyclable AMA1-based plasmid which allows unlimited number of genomic modifications without the limitation of integrative selection markers. As test case, we successfully targeted the wetA gene, which encodes a regulator of conidiophore development. Finally, CRISPR/Cas9-derived ΔwetA strains were analyzed. Mutants showed reduced axenic growth, differential pathogenicity and altered conidiogenesis and germination. Additionally, P. digitatum and P. expansum ΔwetA mutants showed distinct sensitivity to fungal antifungal proteins (AFPs), which are small, cationic, cysteine-rich proteins that have become interesting antifungals to be applied in agriculture, medicine and in the food industry. With this work, we demonstrate the feasibility of the CRISPR/Cas9 system, expanding the repertoire of genetic engineering tools available for these two important postharvest pathogens and open up the possibility to adapt them to other economically relevant phytopathogenic fungi, for which toolkits for genetic modifications are often limited. [ABSTRACT FROM AUTHOR]

Blue mold caused by Penicillium expansum is one of the most common apple diseases, and it is becoming a serious threat in apple production. The strain Bacillus amyloliquefaciens Ba168 showed high levels of antimicrobial activity in our previous study. To analyze the antimicrobial protein of Ba168, a high-resolution LC-MS/MS proteomic analysis was performed. A total of 1155 proteins were identified from 5233 unique peptides. A total of 16 potential antimicrobial-activity-related proteins were identified; 10 of these proteins have direct antimicrobial effects, while 6 of these proteins are associated with the formation of antimicrobial substances. Then, an antifungal protein of Ba168 was isolated and purified by the sequential chromatography of DEAE Bio-sep FF anion exchange and Sephadex G-75. The single protein, named BP8-2, showed antifungal activity towards Penicillium expansum. The peptide mass fingerprinting of the protein band of BP8-2 had a high similarity with the amino acid sequences of flagellin protein. The results showed that BP8-2 significantly inhibited the growth of P. expansum and slowed the spread of apple blue mold. The results indicated that flagellin is one of the important antimicrobial substances from Ba168. [ABSTRACT FROM AUTHOR]

Penicillium expansum causes blue mold in fruit, leading to the accumulation of patulin, a harmful toxin. Current detection methods for patulin are costly and complex, highlighting the need for a simplified approach. This study investigates the impact of P. expansum on 'Golden Delicious' and 'Fuji' apples, focusing on significant changes in lesion characteristics and fruit properties. Correlation analysis revealed strong positive associations between patulin content and lesion diameter, lesion depth, and fruit weight loss, while negative correlations were observed with apple firmness and flesh firmness. Of the four machine learning models used - Back Propagation Neural Network (BPNN), Random Forest (RF), Extreme Gradient Boosting (XGBoost) and Gradient Boosting Regression Tree (GBRT) - all showed good predictive performance without overfitting the data. BPNN outperformed the others in accurately predicting patulin accumulation (Golden Delicious: RMSE=0.72, MAE=0.217, R²=0.982; Fuji: RMSE=0.289, MAE=0.08, R²=0.994). Key features influencing patulin accumulation, identified using SHapley Additive exPlanation (SHAP) measures, included lesion diameter, lesion depth, and fruit weight loss. This research highlights the potential of machine learning to predict patulin accumulation based on these critical factors, providing a simplified detection method for postharvest fruit quality management. • The BPNN model excels at accurately predicting patulin levels in apples. • SHAP measures identify key characteristics that influence patulin accumulation. • Simplified patulin detection using lesion characteristics and fruit characteristics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Penicillium expansum has the smallest mitogenome among other Penicillium mitogenomes reported. • Mitochondrial genomes of all Penicillium species retained the core protein-coding genes and had fewer intronic regions compared to other ascomycetes. • Among Penicillium species, cob exhibited the highest genetic distance while atp 8 exhibited the lowest genetic distance. Penicillium expansum is an important phytopathogenic fungus that causes blue mold disease. In this study, the novel mitochondrial genome of P. expansum was sequenced, assembled, annotated, and compared with the previously published Penicillium mitogenomes. P. expansum mitogenome is composed of circular DNA molecules with a genome size of 25,496 bp. It encodes 16 protein-encoding genes (PCGs), two rRNA genes, and 25 tRNA genes. Comparative analysis with six other Penicillium species revealed that gene length, GC content, AT skew, and GC skew were variable among the core protein-coding genes. The Penicillium species' gene synteny analysis identified several gene rearrangements. Among the core 15 PCGs, atp8 had the lowest K2P genetic distance, which shows that this gene is highly conserved. The Ka/Ks value of most PCGs was less than 1, which shows that these genes have undergone purifying selection. Phylogenetic analysis based on 14 concatenated core mitochondrial genes revealed that P. expansum shares a close relationship with P. solitum. This study served as a first report on the complete mitochondrial genome of P. expansum and its comparative analysis that will contribute to population genetics and rapid evolutionary studies among Penicillium species. [ABSTRACT FROM AUTHOR]

Fruit decay and toxin contamination caused by pathogenic fungi have attracted public attention. As the causal agent of blue mold, Penicillium expansum has caused serious losses to various fruit. Additionally, P. expansum produces patulin, a carcinogenic toxin that can contaminate fruit and fruit products. Wuyiencin has been widely used to control fungal diseases. However, the inhibitory effects of wuyiencin on P. expansum and its mechanisms of action are still unclear. In this study, the effects of wuyiencin on the growth, spore germination, virulence and patulin production of P. expansum were investigated. Possible mechanisms were examined and verified by transcriptomic analysis, RT-qPCR, FDA/PI staining and cell leakage detection. Wuyiencin inhibited the growth, spore germination, virulence and patulin production of P. expansum. A large number of genes encoding membrane proteins were up-regulated and expressed. However, genes encoding membrane-bound organelles were down-regulated under wuyiencin treatment. The integrity of the cell membrane was destroyed. In addition, the expression of some genes related to patulin synthesis and translation/protein processing was altered. These results suggested that wuyiencin effectively controlled the growth, spore germination, virulence, and patulin production of P. expansum by destroying cell membrane integrity and altering the expression of patulin synthesis-related genes and translation/protein processing related genes. • Wuyiencin inhibited the growth, virulence and patulin production of P. expansum. • Wuyiencin could disrupt the cell membrane integrity of P. expansum. • Patulin synthesis-related genes expression in P. expansum were altered by wuyiencin. • Wuyiencin altered the expression of translation/protein processing-related genes. [ABSTRACT FROM AUTHOR]

Penicillium expansum is a necrotrophic plant pathogen that has a broad range of fruit hosts and is responsible for blue mold rot. This rot has a significant impact on the fruit industry, causing economic losses during storage, transport, and sale. Polygalacturonase (PGs) enzymes are essential for pathogenic fungi to break down pectin, as they hydrolyze the polygalacturonic acid chain along the oxygen bridge. This enzyme has been identified in decayed tissue and is linked to multiple soft rot diseases. This study encompasses a thorough examination of the PGs gene family within the genome of P. expansum , utilizing a genome-wide analysis approach. As a result, a total of seven PG genes were successfully found. These genes were phylogenetically divided into four distinct clades. The gene structural characteristics of each group exhibited a fundamental level of conservation. Furthermore, the gene architectures and motif compositions exhibited robust evidence in favor of the credibility of the phylogenetic relationship. Motif analysis reveals that most of the motifs predicted had Glycosyl hydrolases family 28 conserved domains (PF00295). Analysis of RNA-seq data and the PG genes identified by RT-qPCR were mostly upregulated. Hence, comprehending the characteristics of PePGs holds significant scientific importance and will offer comprehensive insights into the PG superfamily in P. expansum and will make a valuable contribution to the ongoing validation of functional genes. • Genome-wide analysis reveals seven PG gene with GH28 domain in Penicillium expansum genome. • The seven PG genes are subgroup into four families and distributed on seven chromosomes. • Phylogenetic analysis reveals that P. expansum PGs are closely related to P. italicum. • RT-qPCR analysis confirms that most PG genes in P. expansum genome were upregulated. [ABSTRACT FROM AUTHOR]

Plants resist the invasion and establishment of pathogens through the existence of structural barriers and biochemical response mechanisms. In this regard, long non-coding RNAs (lncRNAs) have been found to play a role in various plant growth and developmental processes, as well as plant disease resistance. This study used high-throughput sequencing and bioinformatics to identify lncRNAs in kiwifruit and predict their function based on their inferred target genes. A total of 591 differentially expressed lncRNAs and 1819 mRNAs were identified in kiwifruit samples infected with P. expansum for 24 h. GO enrichment analysis indicated that the highest number of differentially expressed genes (DEGs) fell into the biological processes category of the three major ontology categories. KEGG pathway analysis indicated that most DEGs were annotated in the Plant-pathogen interaction and Plant hormone signal transduction pathways. LncRNAs in kiwifruit may be involved in the response to pathogen infections through salicylic acid (SA), gibberellin (GA), and abscisic acid (ABA) pathways. In this regard, genes, such as PP2C , GA20ox , and A-ARR , exhibited varying degrees of differential expression in kiwifruit in response to P. expansum infection. Our results provide insight into the molecular response of kiwifruit to invasion by P. expansum and provide a theoretical foundation for understanding and improving disease resistance. [Display omitted] • Identification of lncRNAs in tissues of kiwifruit. • Differential expression analysis of lncRNAs and mRNAs. • Studying the integrated relationship of lncRNAs and mRNAs. • Confirming the reliability of the differential expression genes by RT-qPCR. [ABSTRACT FROM AUTHOR]

Ypt GTPases are the largest subfamily of small GTPases involved in membrane transport. Here, a PeYpt7 gene deletion mutant of P. expansum was constructed. The Δ PeYpt7 mutant showed reduced colony growth with abnormal mycelial growth, reduced conidiation, and insufficient spore development. The mutation rendered the pathogen susceptible to osmotic stress and cell wall stressors. In addition, the absence of PeYpt7 reduced patulin production in P. expansum and significantly limited gene expression (PatG , PatH , PatI , PatD , PatF , and PatL). In addition, the mutant showed attenuated virulence in infected fruit and reduced expression of pathogenic factors was (PMG , PG , PL , and GH1). Thus, PeYpt7 modulates the growth, morphology, patulin accumulation, and pathogenicity of P. expansum by limiting the expression of related genes. • PeYpt7 deletion inhibited growth and development of P. expansum. • PeYpt7 deletion suppressed patulin biosynthesis. • PeYpt7 deletion attenuated the virulence of P. expansum on apple and pear fruits. [ABSTRACT FROM AUTHOR]

Antifungal proteins (AFPs) from filamentous fungi have enormous potential as novel biomolecules for the control of fungal diseases. However, little is known about the biological roles of AFPs beyond their antifungal action. Penicillium expansum encodes three phylogenetically different AFPs (PeAfpA, PeAfpB and PeAfpC) with diverse profiles of antifungal activity. PeAfpA stands out as a highly active AFP that is naturally produced at high yields. Here, we provide new data about the function of PeAfpA in P. expansum through phenotypical characterization and transcriptomic studies of null mutants of the corresponding afpA gene. Mutation of afpA did not affect axenic growth, conidiation, virulence, stress responses or sensitivity towards P. expansum AFPs. However, RNA sequencing evidenced a massive transcriptomic change linked to the onset of PeAfpA production. We identified two large gene expression clusters putatively involved in PeAfpA function, which correspond to genes induced or repressed with the production of PeAfpA. Functional enrichment analysis unveiled significant changes in genes related to fungal cell wall remodeling, mobilization of carbohydrates and plasma membrane transporters. This study also shows a putative co-regulation between the three afp genes. Overall, our transcriptomic analyses provide valuable insights for further understanding the biological functions of AFPs. [ABSTRACT FROM AUTHOR]

Sporidiobolus pararoseus Y16, a species of significant ecological importance, has distinctive physiological and biological regulatory systems that aid in its survival and environmental adaptation. The goal of this investigation was to understand the complex interactions between physiological and molecular mechanisms in pear fruits as induced by S. pararoseus Y16. The study investigated the use of S. pararoseus Y16 and ascorbic acid (VC) in combination in controlling blue mold decay in pears via physiological and transcriptomic approach. The study results showed that treatment of S. pararoseus Y16 with 150 μg/mL VC reduced pears blue mold disease incidence from 43% to 11%. Furthermore, the combination of S. pararoseus Y16 and VC significantly inhibited mycelia growth and spore germination of Penicillium expansum in the pear's wounds. The pre-treatment did not impair post-harvest qualities of pear fruit but increased antioxidant enzyme activity specifically polyphenol oxidase (PPO), peroxidase (POD), catalase (CAT) activities as well as phenylalanine ammonia-lyase (PAL) enzyme activity. The transcriptome analysis further uncovered 395 differentially expressed genes (DEGs) and pathways involved in defense mechanisms and disease resistance. Notable pathways of the DEGs include plant-pathogen interaction, tyrosine metabolism, and hormone signal transduction pathways. The integrative approach with both physiological and transcriptomic tools to investigate postharvest pathology in pear fruits with clarification on how S. pararoseus Y16 enhanced with VC, improved gene expression for disease defense, and create alternative controls strategies for managing postharvest diseases. • Ascorbic acid and yeast combination increased PPO, POD, PAL, and CAT enzyme activities. • Ascorbic acid improved S. pararoseus Y16's altered 395 DEGs in pear fruits. • Ascorbic acid improved S. pararoseus Y16's biocontrol efficacy against P. expansum. [ABSTRACT FROM AUTHOR]

Penicillium expansum is the main pathogen in the postharvest storage of apples. Penicilliosis caused by P. expansum infection not only seriously affects the appearance and quality of fruits, but also the secondary metabolite Patulin (PAT) can cause harm to human health. Until now, little attention has been paid to the molecular mechanism of P. expansum infecting apples. Studying its molecular mechanism can help us better prevent and control apple postharvest blue mold. In this present investigation, we will use Label-Free technology to perform proteomic sequencing on apple samples at key time points of P. expansum infection, explore and screen key proteins and metabolic pathways during infection, and use Parallel Reaction Monitoring (PRM) technology to thoroughly validate proteomic data. The infection of P. expansum activates the MAPK signaling pathway, plant-pathogen interaction metabolic pathway and phenylpropanoid biosynthesis pathway of apple, participates in the regulation of ROS generation and oxidative stress process, promotes the synthesis of lignin and flavonoids, and the synthesis of Pathogenesis-Related Protein helps apple directly defend against P. expansum infection. This study provides the foundation for relevant postharvest control strategies, paving the way for further exploration of the proteome of pathogens infecting fruit and vegetables. Proteins are macromolecules essential to the life of organisms, as they participate in the function and structure of cells. Proteomics technology is currently one of the important means to study the the response mechanism of pathogenic bacteria to plant infection, which can reveal the essence of physiological and pathological processes and help to clarify the possible relationship between protein abundance and plant stress. The present study essentially uses recent proteome analysis technology, namely label-free and PRM techniques, and lays the foundations for studying the of the infection response between P. expansum and apples. In particular, it provides a broad perspective on the molecular mechanism of P. expansum in the early stage of apple infection through detailed functional exploration and verification of associated proteins. Thus, it provides a theoretical basis for preventing and treating apple postharvest blue mold. [Display omitted] • Proteomic data were validated using Parallel Reaction Monitoring (PRM). • Label-free technique was used to screened the key proteins of P. expansum infection. • Label-free technique was used to study the metabolic pathways of P. expansum infection. [ABSTRACT FROM AUTHOR]

Aims: This research sought to improve the ability of biocontrol yeast to suppress postharvest fungal disease and explore possible mechanisms of action. Methods and Results: The addition of 2% sodium glutamate (SG), which is edible and recognized as safe, enhances the inhibitory effect of Rhodosporidium paludigenum Fell & Tallman on Penicillium expansum in vivo and in vitro. Rhodosporidium paludigenum cells grown in medium with a final concentration of 2% SG, displayed viability under a variety of stress conditions, including sodium chloride (NaCl), calcofluor white (CFW), Congo red (CR) and sodium dodecyl sulphate (SDS). Activity and relative gene expression levels of 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 altered in the presence of SG. Levels of reactive oxygen species (ROS) increased in cells grown in the presence of SG as well as the content of several amino acids. Conclusions: In the presence of 2% SG R. paludigenum inhibited P. expansum and exhibited tolerance to a number of stressful conditions which may involve the upregulation of antioxidant enzymes and amino acids. Significance and Impact of the Study: The ability of culture conditions to enhance the fungal suppressive abilities of yeast has the potential to enhance the management of postharvest disease in fruit. [ABSTRACT FROM AUTHOR]

The present work aimed to study the essential oil (EO) variation of Dracocephalum moldavica L. under different phenological stages. The EO yield was highest in the flowering stage, followed by floral budding, fruit set, and vegetative stages. Twenty-three components in EOs were identified by GC-MS and quantified using GC-FID. Geranyl acetate (31–50 %), geranial (16–27 %), geraniol (12–13.4 %) and neral (10.67–17.30 %) were four main constituents. Antifungal assays of EO through mycelial growth inhibition percentages (MGI %) with four concentrations (0, 250, 500, and 750 µl/l) showed concentration-dependent responses. EOs showed the high potential of antifungal activity with ID50 values of (89–145), (27–88) and (183–339) µl/l and ID90 values of (667–1293), (509–1296), and (389–866) µl/l for Aspergillus niger, Penicillium expansum, and Trichoderma harzianum respectively. EO of D. moldavica showed considerable promise as a natural bio-preservative and bio-antifungal agent. [ABSTRACT FROM AUTHOR]

Antioxidant and antifungal activities of three essential oils (EOs): Melaleuca ericifolia Smith (rosalina; REO), Melaleuca quinquenervia (niaouli; NEO) and Abies alba (fir; FEO) were determined. The antioxidant capacity was investigated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and the disc diffusion method was applied to evaluate their antifungal efficacy (in four concentrations 62.5 µL/L, 125 µL/L, 250 µL/L, 500 µL/L used) against Penicillium (P.) expansum microscopic filamentous fungus isolated from bread samples. From the findings it can be clearly evident that antioxidant activities of the EOs were very weak with values ranging from 25.81 ± 7.8 TEAC (6.2 ± 1.4%; FEO) to 162.0 ± 2.1 TEAC (15.9 ± 0.4%; NEO). Regarding antifungal properties, our results revealed that the effects of the EOs on P. expansum growth inhibition were dose-dependent, and they were proportionally increased with increasing EOs concentrations. Detected inhibition zones ranged from 0.00 ± 0.00 mm (for all EOs at 62.5 µL/L) to 11.67 ± 1.15 mm (for REO at 500 µL/L). In conclusion, all analyzed EOs possess promising in vitro antifungal activity (despite their weak antioxidant capacity) suggesting their use as a promising natural preservative in the food industry. [ABSTRACT FROM AUTHOR]

Summary: Although several studies have shown the ability of l‐glutamate (glutamate) to mitigate the stress imposed by pathogens, the underlying mechanism is still in its infancy. To gain further knowledge, this study focussed on the effect of glutamate on primary nitrogen and carbon metabolisms during apple‐Penicillium expansum interaction. The obtained result showed that glutamate could effectively restrict blue mould rot development in apples, but had no direct impact on fungal growth in vitro. The application of glutamate increased the level of nitrogen in apples, resulting in a disrupted balance of carbon and nitrogen. Consistently, the key enzymes glutamine synthetase (GS) and glutamate synthase (GOGAT) involved in the GS/GOGAT cycle, and the deaminating activity of glutamate dehydrogenase (GDH), forming 2‐oxoglutarate and ammonium from glutamate, were promptly stimulated by glutamate. Interestingly, glutamate led to considerable consumption of the tricarboxylic acid (TCA) cycle intermediates, such as isocitric acid and citric acid, accompanied by the enhancement of malate dehydrogenase and succinate dehydrogenase activities. Collectively, exogenous application of glutamate might confer blue mould resistance in apples, at least in part, by redirecting host's primary nitrogen and carbon metabolisms, such as the activation of the GS/GOGAT cycle, deaminating activity of GDH and the TCA cycle. [ABSTRACT FROM AUTHOR]

Penicillium expansum is a necrotrophic wound fungal pathogen that secrets virulence factors to kill host cells including cell wall degrading enzymes (CWDEs), proteases, and mycotoxins such as patulin. During the interaction between P. expansum and its fruit host, these virulence factors are strictly modulated by intrinsic regulators and extrinsic environmental factors. In recent years, there has been a rapid increase in research on the molecular mechanisms of pathogenicity in P. expansum; however, less is known regarding the bacteria–fungal communication in the fruit environment that may affect pathogenicity. Many bacterial species use quorum-sensing (QS), a population density-dependent regulatory mechanism, to modulate the secretion of quorum-sensing signaling molecules (QSMs) as a method to control pathogenicity. N-acyl homoserine lactones (AHLs) are Gram-negative QSMs. Therefore, QS is considered an antivirulence target, and enzymes degrading these QSMs, named quorum-quenching enzymes, have potential antimicrobial properties. Here, we demonstrate that a bacterial AHL lactonase can also efficiently degrade a fungal mycotoxin. The mycotoxin is a lactone, patulin secreted by fungi such as P. expansum. The bacterial lactonase hydrolyzed patulin at high catalytic efficiency, with a kcat value of 0.724 ± 0.077 s−1 and KM value of 116 ± 33.98 μM. The calculated specific activity (kcat/KM) showed a value of 6.21 × 10³ s−1M−1. While the incubation of P. expansum spores with the purified lactonase did not inhibit spore germination, it inhibited colonization by the pathogen in apples. Furthermore, adding the purified enzyme to P. expansum culture before infecting apples resulted in reduced expression of genes involved in patulin biosynthesis and fungal cell wall biosynthesis. Some AHL-secreting bacteria also express AHL lactonase. Here, phylogenetic and structural analysis was used to identify putative lactonase in P. expansum. Furthermore, following recombinant expression and purification of the newly identified fungal enzyme, its activity with patulin was verified. These results indicate a possible role for patulin and lactonases in inter-kingdom communication between fungi and bacteria involved in fungal colonization and antagonism and suggest that QQ lactonases can be used as potential antifungal post-harvest treatment. [ABSTRACT FROM AUTHOR]

Penicillium expansum is one of the most common and destructive post-harvest fungal pathogens that can cause blue mold rot and produce mycotoxins in fruit, leading to significant postharvest loss and food safety concerns. Arginine methylation by protein arginine methyltransferases (PRMTs) modulates various cellular processes in many eukaryotes. However, the functions of PRMTs are largely unknown in post-harvest fungal pathogens. To explore their roles in P. expansum, we identified four PRMTs (PeRmtA, PeRmtB, PeRmtC, and PeRmt2). The single deletion of PeRmtA, PeRmtB, or PeRmt2 had minor or no impact on the P. expansum phenotype while deletion of PeRmtC resulted in decreased conidiation, delayed conidial germination, impaired pathogenicity and pigment biosynthesis, and altered tolerance to environmental stresses. Further research showed that PeRmtC could regulate two core regulatory genes, PeBrlA and PeAbaA, in conidiation, a series of backbone genes in secondary metabolism, and affect the symmetric ω-NG, N’G-dimethylarginine (sDMA) modification of proteins with molecular weights of primarily 16–17 kDa. Collectively, this work functionally characterized four PRMTs in P. expansum and showed the important roles of PeRmtC in the development, pathogenicity, and secondary metabolism of P. expansum. [ABSTRACT FROM AUTHOR]

Blue mold of apple is caused by several different Penicillium species, among which P. expansum and P. solitum are the most frequently isolated. P. expansum is the most aggressive species, and P. solitum is very weak when infecting apple fruit during storage. In this study, we report complete genomic analyses of three different Penicillium species: P. expansum R21 and P. crustosum NJ1, isolated from stored apple fruit; and P. maximae 113, isolated in 2013 from a flooded home in New Jersey, USA, in the aftermath of Hurricane Sandy. Patulin and citrinin gene cluster analyses explained the lack of patulin production in NJ1 compared to R21 and lack of citrinin production in all three strains. A Drosophila bioassay demonstrated that volatiles emitted by P. solitum SA and P. polonicum RS1 were more toxic than those from P. expansum and P. crustosum strains (R27, R11, R21, G10, and R19). The toxicity was hypothesized to be related to production of eight-carbon oxylipins. Putative lipoxygenase genes were identified in P. expansum and P. maximae strains, but not in P. crustosum. Our data will provide a better understanding of Penicillium spp. complex secondary metabolic capabilities, especially concerning the genetic bases of mycotoxins and toxic VOCs. [ABSTRACT FROM AUTHOR]

The blue mold disease caused by Penicillium expansum is one of the most important post-harvest diseases of pears. Some microorganisms and essential oils have the ability to inhibit the growth of P. expansum. The aim of this study was to determine the antagonistic effect of Bacillus subtilis, Trichoderma harzianum and thyme oil in the n the 'Karyağdı' pear cultivar against Penicillium expansum". In vitro antagonism tests, T. harzianum was more effective than Bacillus subtilis and the % inhibition rates were determined as 55.97% and 49.37%, respectively. The mycelial growth of P. expansum was inhibited by 59.62-100% in the contact application of thyme oil and 54.17-100% in the fumigant application. In fruit bioassays, B. subtilis, T. harzianum and thyme oil reduced fruit rot by 31.69-72.37 % at 25 °C and by 22.19 - 66.83 at 0°C. While the contact application of 500 μl / L thyme oil was most effective against caries lesions in pear fruits, the fumigant application of 1% thyme oil showed the least effect. As a result of the studies, it was concluded that it would be beneficial to use thyme oil and antagonistic microorganisms (B. subtilis, T. harzianum) against P. expansum, which is one of the postharvest diseases of pears, due to their environmental friendliness. [ABSTRACT FROM AUTHOR]

Penicilliumphytopathogenic species provoke severe postharvest disease and economiclosses.Penicillium expansumis the main pome fruit phytopathogen whilePenicillium digitatumandPenicillium italicumcause citrus green and blue mold, respectively. Control strategies rely on theuse of synthetic fungicides, but the appearance of resistant strains and safety concerns have ledto the search for new antifungals. Here, the potential application of different antifungal proteins(AFPs) including the threePenicillium chrysogenumproteins (PAF, PAFB and PAFC), as well as theNeosartorya fischeriNFAP2 protein to controlPenicilliumdecay, has been evaluated. PAFB wasthe most potent AFP againstP. digitatum,P. italicumandP. expansum, PAFC and NFAP2 showedmoderate antifungal activity, whereas PAF was the least active protein. In fruit protection assays,PAFB provoked a reduction of the incidence of infections caused byP. digitatumandP. italicuminoranges and byP. expansumin apples. A combination of AFPs did not result in an increase in theefficacy of disease control. In conclusion, this study expands the antifungal inhibition spectrum of theAFPs evaluated, and demonstrates that AFPs act in a species-specific manner. PAFB is a promisingalternative compound to controlPenicilliumpostharvest fruit decay. [ABSTRACT FROM AUTHOR]

Patulin, one of the most common mycotoxins produced primarily by the Penicillium , Aspergillus and Byssochlamys species, is often associated with fruits and fruit-based products. Biodegradation by microbes is an effective method to remove or detoxify mycotoxins. In this study, a bacterial strain with patulin degradation capability was selectively isolated using oxindole, an analogue to patulin, as the sole carbon source, and identified as Pseudomonas poae JSU-Y1 by phylogenetic analysis on the basis of 16S rRNA sequence. This isolated bacterium could inhibit the growth of Penicillium expansum both on plate medium and apple fruit with inhibition ratio of 30.3% and 44.9%, respectively. Up to 87.7% of the initial patulin (2.5 μg/mL) was removed after incubation with Pseudomonas poae JSU-Y1 in liquid medium at 30 °C for 72 h. When challenged with apple juice, 79% of patulin could be degraded by this isolated strain. Additionally, ascladiol was tentatively identified as the patulin degradation intermediate by LC-MS analysis. Taken together, the experiment results indicated that the isolated Pseudomonas poae JSU-Y1 would be a promising bacterial resource to control patulin contamination and toxigenic fungal growth in agricultural products. [Display omitted] • Pseudomonas poae JSU-Y1 can degrade patulin. • P. poae JSU-Y1 exhibits growth inhibition on Penicillium expansum. • P. poae JSU-Y1 reduces blue mold rot of apple fruits. • Ascladiol is tentatively to be the patulin degradation intermediate. [ABSTRACT FROM AUTHOR]

Patulin is a secondary metabolite produced primarily by the fungus Penicillium expansum, responsible for the blue mold disease on apples. It is found in apple products including apple cider when apple juice is added after fermentation. In the present study, two hundred and twenty-five ciderapples of the variety “Bedan”, cultivated in Brittany in France, were sampled from the orchard during harvesting until the storage step, right before processing. The patulin analysis on these samples reported a low contamination at the orchard and a significantly higher-level of contamination in the cider-apples starting from the transporting bin. The percentage of positive samples increased from 6% to 47% after 12 h in the harvesting bin before transporting and reached 95% after 24 h of transporting, decreasing then to 69% at the end of the storage. Penicillium expansum was quantified on the surface of apples using real-time PCR and was observed to be mostly consistent between the harvest and post-harvest steps. It was detected on average, on the surface of 85% of all sampled apples with a mean value around 2.35 × 106 Penicillium expansum DNA/g of apple. Moreover, the changes in the fungal and bacterial epiphytic microbiota in the different steps were studied using a metabarcoding approach. The alpha and beta diversity analysis revealed the presence of unique and more diverse bacterial and fungal communities on the surface of apples picked from the orchard compared to the rest of the sampling steps. Potential indigenous biological control agents were identified on the surface of sampled apples. Future perspective includes developing actions of prevention and control of the contamination by Penicillium expansum during the harvest and along the various critical post-harvest stages before transformation in a sustainable development concern. [ABSTRACT FROM AUTHOR]

Fungal attacks on stored fruit and vegetables are responsible for losses of products. There is an active research field to develop alternative strategies for postharvest disease management, and the use of biocontrol agents represents a promising approach. Understanding the molecular bases of the biocontrol activity of these agents is crucial to potentiate their effectiveness. The yeast Papiliotrema terrestris is a biocontrol agent against postharvest pathogens. Phenotypic studies suggest that it exerts its antagonistic activity through competition for nutrients and space, which relies on its resistance to oxidative and other cellular stresses. In this study, we developed tools for genetic manipulation in P. terrestris to perform targeted gene replacement and functional complementation of the transcription factors Yap1 and Rim101. In vitro phenotypic analyses revealed a conserved role of Yap1 and Rim101 in broad resistance to oxidative stress and alkaline pH sensing, respectively. In vivo analyses revealed that P. terrestris yap1D and rim101D mutants display decreased ability to colonize wounded fruit compared to that of the parental wild-type (WT) strain; the yap1D mutant also displays reduced biocontrol activity against the postharvest pathogens Penicillium expansum and Monilinia fructigena, indicating an important role for resistance to oxidative stress in timely wound colonization and biocontrol activity of P. terrestris. In conclusion, the availability of molecular tools developed in the present study provides a foundation to elucidate the genetic mechanisms underlying biocontrol activity of P. terrestris, with the goal of enhancing this activity for the practical use of P. terrestris in pest management programs based on biological and integrated control. [ABSTRACT FROM AUTHOR]

Blue mold caused by Penicilliumexpansum (P. expansum) causes severe fruit losses, and there is an urgent need to explore safe natural products to control post-harvest diseases and investigate potential antifungal mechanisms. In this study, flavonoids (GBLF) were extracted and purified from mature Ginkgo biloba leaves (GBL). According to an analysis of UV-visible spectroscopy, FTIR, and LC-MS, GBLF contained 10 flavonoids, including 8 quercetin and kaempferol derivatives. The inhibition halo diameter by GBLF ethanol solution reached a maximum of 11.2 ± 0.3 mm, which significantly inhibited the growth of P. expansum. In the GBLF ethanol solution treatment trial, the mycelial cells of P. expansum reached their maximum cell conductivity, protein leakage rate, and malondialdehyde (MDA) content at 48 h, with values of 3.89 ± 0.17 ms/cm, 5.22 ± 0.08 mg/L, and 5.76 ± 0.09 mmol/kg, respectively, which were 2.7, 13.74, and 4.76 times higher than those of the control. Compared with 12 h, the activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) in the enzyme antioxidant system were 3.38 ± 0.11 U/mg, 5.23 ± 0.09 U/mg, and 2.66 ± 0.10 U/mg, respectively, which decreased by 30.2%, 20.09%, and 51.47%. In conclusion, quercetin and kaempferol derivatives in GBLF may act on P. expansum by increasing the permeability of cell membranes, reducing enzymatic antioxidant activity, and accelerating lipid peroxidation.Graphical Abstract: Blue mold caused by Penicilliumexpansum (P. expansum) causes severe fruit losses, and there is an urgent need to explore safe natural products to control post-harvest diseases and investigate potential antifungal mechanisms. In this study, flavonoids (GBLF) were extracted and purified from mature Ginkgo biloba leaves (GBL). According to an analysis of UV-visible spectroscopy, FTIR, and LC-MS, GBLF contained 10 flavonoids, including 8 quercetin and kaempferol derivatives. The inhibition halo diameter by GBLF ethanol solution reached a maximum of 11.2 ± 0.3 mm, which significantly inhibited the growth of P. expansum. In the GBLF ethanol solution treatment trial, the mycelial cells of P. expansum reached their maximum cell conductivity, protein leakage rate, and malondialdehyde (MDA) content at 48 h, with values of 3.89 ± 0.17 ms/cm, 5.22 ± 0.08 mg/L, and 5.76 ± 0.09 mmol/kg, respectively, which were 2.7, 13.74, and 4.76 times higher than those of the control. Compared with 12 h, the activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) in the enzyme antioxidant system were 3.38 ± 0.11 U/mg, 5.23 ± 0.09 U/mg, and 2.66 ± 0.10 U/mg, respectively, which decreased by 30.2%, 20.09%, and 51.47%. In conclusion, quercetin and kaempferol derivatives in GBLF may act on P. expansum by increasing the permeability of cell membranes, reducing enzymatic antioxidant activity, and accelerating lipid peroxidation. [ABSTRACT FROM AUTHOR]

Blue mold decay caused by Penicillium expansum is a global destructive postharvest disease, which has brought huge economic losses to the pear industry. Transcription factors play an important role in pear anti-infection defense, and it has been observed that they have multiple functions. However, the roles of numerous TFs in the defense of pear against P. expansum have not been adequately explored. In this study, ATAC-seq was used to screen the TFs of pear against P. expansum , thereby understanding the chromatin-mediated gene regulation in the defense of pear against infection. The peak of differential expression enriched 9 transcription factors (AGL27, AT5G02460, AT2G28810, AT5G66940, AT3G46070 and OBP1, TCP3, BPC1 and TCP17). The up-regulated genes in our study were implicated in the MAPK signaling pathway-plant, plant hormone signal transduction pathway, plant-pathogen interaction pathway, glutathione metabolism pathway, phenylpropanoid biosynthesis, flavonoid biosynthesis pathway and carotenoid biosynthesis pathway were identified. Especially the transcription factors TGA, gene SAUR and CYCD3 in plant hormone signal transduction pathway and NCED , CYP707A in carotenoid biosynthesis pathway were differentially regulated. RT-qPCR analysis of twelve randomly selected differentially expressed peak-related genes confirmed the accuracy of ATAC-seq analysis of P. expansum infected pear. • Transcription factors of pear against P. expansum infection were screened by ATAC-seq. • MAPK signaling pathway in pear was activated by P. expansum. • SAUR , CYCD3 and TF TGA in plant hormone signal transduction pathway were up-regulated. • NCED and CYP707A in carotenoid biosynthesis pathway were up-regulated. [ABSTRACT FROM AUTHOR]

Blue mold caused by Penicillium expansum is a prevalent postharvest disease that affects quality of apples during storage and transportation and is responsible for considerable, economic losses to the apple industry. Patulin (PAT), a secondary metabolite of P. expansum , is toxic and widely found in apples and their products, which is hazardous to human health. In this study, Fuji apples were inoculated with P. expansum then subjected to both room-temperature storage and cold storage. Measurements of the lesion diameter and PAT content revealed that the growth rate of P. expansum was lower during cold storage but the PAT content was higher, even in samples with the same lesion diameter. Non-targeted high-resolution mass spectrometry was employed to examine the metabolic changes in the infected tissues for a fixed lesion diameter (after 24 d of cold storage and 7 d of room-temperature storage). Clear differences were observed in the contents of organic acids, lipids, flavonoids, sugars, and other metabolites. Compared with the apples stored at room temperature, downregulation of metabolic pathways related to disease resistance and upregulation of those related to PAT synthesis at cold storage. The obtained results further elucidate the effects of temperature on P.expansum infection and apple resistance, thus providing a theoretical basis for the prevention and control of this problematic plant pathogen. • Low temperature inhibited the growth of Penicillium expansum. • Low temperature does not inhibit patulin synthesis, but may stimulate it. • The expression of PAT synthesis-related pathways was affected by temperature. [ABSTRACT FROM AUTHOR]

Chitosan is a natural polysaccharide that is abundant, biocompatible and exhibits effective antifungal activity against various pathogenic fungi. However, the potential intracellular targets of chitosan in pathogenic fungi and the way of activity of chitosan are far from well known. The present work demonstrated that chitosan could inhibit Penicillium expansum , the principal causal agent of postharvest blue mold decay on apple fruits, by binding to DNA and triggering apoptosis. UV–visible spectroscopy, fluorescence spectroscopy and electrophoretic mobility assay proved the interaction between chitosan and DNA, while atomic force microscope (AFM) observation revealed the binding morphology of chitosan to DNA. Chitosan could inhibit in vitro DNA replication, and cell cycle analysis employing flow cytometry demonstrated that cell cycle was retarded by chitosan treatment. Furthermore, the reactive oxygen species (ROS) assay and membrane potential analysis showed that apoptosis was induced in P. expansum cells after exposure to chitosan. In conclusion, our results confirmed that chitosan interacts with DNA and induces apoptosis. These findings are expected to provide a feasible theoretical basis and practical direction for the promoting and implementing of chitosan in plant protection and further illuminate the possible antifungal mechanisms of chitosan against fungal pathogens. [ABSTRACT FROM AUTHOR]

As a core component of the Pal/Rim-pH signaling pathway in pathogenic fungi, the transcription factor PacC induces the partial acidification of host tissues and modulates the activity of extracellular fungal enzymes. However, the spatial regulation of PacC on phospholipase activity in fruit has not been reported. In this study, the role of the PePacC in Penicillium expansum was investigated by analyzing pH, phospholipid metabolism, cell membrane permeability, and malondialdehyde (MDA) levels in different tissues of apple fruit inoculated with a PePacC -deficient strain of P. expansum (Δ PePacC). The results showed that the pathogenicity and acidification ability were impaired when PePacC was deleted in P. expansum. Compared to the WT inoculation, deletion of PePacC spatially and dynamically regulated the activities of phospholipase A1 (PLA1), PLA2, PLC, and PLD, and the levels of phosphatidylcholine (PC), inositol 1, 4, 5-trisphosphate (IP3), phosphatidylinositol 4, 5-bisphosphate (PIP2), phosphatidylinositol (PI), and phosphatidic acid (PA), and altered the extent of damage to the cell membrane integrity at and outside of the junction of the leading edge of decay in apple fruit during P. expansum infection. Taken together, the present study showed that PacC could mediate the acidifying ability of P. expansum to colonize host fruit, and dynamically regulate the spatial changes of phospholipid metabolism in different apple tissues. Furthermore, both host defense responses and pathogen virulence mechanisms are involved in the apples- P. expansum interaction. • The virulence and acidification ability of Δ PePacC mutant was impaired in apples. • PePacC regulated phospholipid metabolism during P. expansum infection in apples. • PePacC deletion altered the damage to cell membrane integrity in infected apples. [ABSTRACT FROM AUTHOR]

Penicillium expansum (P. expansum) is a harmful pathogenic mold responsible for huge postharvest losses in apples. Epsilon‐poly‐L‐lysine (ε-PL) is a non-toxic antiseptic peptide derived from Streptomyces albulus. Many food preservative strategies use ε-PL to suppress foodborne pathogens in condiments, cakes, fruit and vegetable juices. In the present research, ε-PL's inhibitory effects against P. expansum in vitro and in apples were investigated. The molecular mechanisms of ε-PL inhibiting P. expansum in apples were investigated by transcriptome analysis. Results showed that doses of 600 mg L−1 of ε-PL could prevent the development of P. expansum in vitro and control blue mold decay in apples. Plausible mechanisms of ε-PL against P. expansum in apples include: (i) reduction of antioxidant potential, including decreasing the expression of genes encoding superoxide dismutase (SOD), catalase (CAT), glutathione s-transferase (GST), xanthine dehydrogenase (XDH), D -amino-acid oxidase (DAO), weakening ROS scavenging ability of P. expansum cells and causing oxidative damage to cell, (ii) weakening its virulence towards apples, including reducing the expression of genes coding for cell wall degrading enzymes (CWDEs) such as pectinase and cellulase, (iii) disrupting mitochondrial function of P. expansum , including reducing expression of several rate-limiting enzyme coding genes of energy metabolic pathways such as EMP, TCA cycle and oxidative phosphorylation, which interfered with the cells' energy metabolism, leading to insufficient ATP synthesis, weakening P. expansum 's resistance to external stress, and finally slowing down the invasion process into apples, (ⅳ) damaging the membrane integrity of P. expansum , including reducing the expression of genes encoding diaphragm wall degradation enzymes, cytomembrane lipid and ergosterol synthetase, multi-drug transporter, and inhibiting the differentiation of conidia. • 600 mg L−1 of ε-PL can significantly inhibit P. expansum in vitro or in apples. • ε-PL decreased the expression of genes encoding antioxidant enzyme of P. expansum. • ε-PL reduced the expression of genes coding CWDEs, weakened its virulence to apples. • ε-PL interfered the mitochondrial function and energy metabolism of P. expansum. • ε-PL damaged the membrane integrity of P. expansum in apples. [ABSTRACT FROM AUTHOR]

Penicillium expansum is a major postharvest pathogen that mainly threatens the global pome fruit industry and causes great economic losses annually. In the present study, the antifungal effects and potential mechanism of cinnamon oil against P. expansum were investigated. Results indicated that 0.25 mg L−1 cinnamon oil could efficiently inhibit the spore germination, conidial production, mycelial accumulation, and expansion of P. expansum. In addition, it could effectively control blue mold rots induced by P. expansum in apples. Cinnamon oil could also reduce the expression of genes involved in patulin biosynthesis. Through a proteomic quantitative analysis, a total of 146 differentially expressed proteins (DEPs) involved in the carbohydrate metabolic process, most of which were down-regulated, were noticed for their large number and functional significance. Meanwhile, the expressions of 14 candidate genes corresponding to DEPs and the activities of six key regulatory enzymes (involving in cellulose hydrolyzation, Krebs circle, glycolysis, and pentose phosphate pathway) showed a similar trend in protein levels. In addition, extracellular carbohydrate consumption, intracellular carbohydrate accumulation, and ATP production of P. expansum under cinnamon oil stress were significantly decreased. Basing on the correlated and mutually authenticated results, we speculated that disturbing the fungal carbohydrate metabolic process would be partly responsible for the inhibitory effects of cinnamon oil on P. expansum growth. The findings would provide new insights into the antimicrobial mode of cinnamon oil. [ABSTRACT FROM AUTHOR]