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Brown rot, aspergillosis and soft rot are the primary diseases of postharvest peach fruit. Our study aimed to investigate the biocontrol effect of Wickerhamomyces anomalus on the primary postharvest diseases of peach fruit and to explore its underlying physiological mechanism. The findings demonstrated that W. anomalus had an obvious inhibitory effect on Monilinia fructicola , Aspergillus niger and Rhizopus stolonifer. At the same time, W. anomalus can grow stably on the wound and surface of peach fruit at 25 °C and 4 °C and can form biofilm. W. anomalus increased the activity of resistance-related enzymes such as PPO, POD, GLU and the content of secondary metabolites such as total phenols, flavonoids and lignin in peach. Furthermore, the application of W. anomalus led to a reduced MDA level in peach fruit and increased activity of the active oxygen-scavenging enzyme system. This increase involved various antioxidant defense enzymes such as SOD and CAT, as well as ascorbic acid-glutathione (AsA-GSH) enzymes, including APX, GPX, GR, DHAR, and MDHAR. Our findings demonstrate that W. anomalus exerts its biocontrol effect by growing rapidly, competing with pathogens for nutrition and space, and enhancing the disease resistance and antioxidative capabilities of the peach fruit. • W. anomalus could control brown rot, aspergillosis and soft rot decay of peach • W. anomalus can stably colonize the surface and wounds of peach • W. anomalus enhanced the defense enzyme (PPO, POD, GLU) activities of peach • W. anomalus increased flavonoids, phenolic and lignin content of peach • W. anomalus increased the antioxidant defense enzymes and AsA-GSH enzymes in peach [ABSTRACT FROM AUTHOR]

Postharvest disease of pears caused by pathogens results in great economic losses. The aim of this research was to isolate a strain of potential antagonistic yeast from soil of orchards, and to test the control efficacy against postharvest blue mold decay of pears. By molecular biological identification based on comparative sequence analysis of 5.8S rDNA gene, the antagonistic strain was identified as Wickerhamomyces anomalus. The results showed that W. anomalus significantly reduced the disease incidence and lesion diameter of blue mold of pears compared with the control in vivo. The disease incidence caused by Penicillium expansum of pears was only 5.56%, when treated with 1 × 108 cells/mL W. anomalus , compared with 100% disease incidence of the control. In vitro test showed that W. anomalus reduced the spore germination rate and germ tube length of P. expansum. Meanwhile, polyphenoloxidase (PPO), peroxidase (POD), catalase (CAT) and chitinase (CHI) activities of the pears treated by W. anomalus were significantly higher than that of the control. And the expression levels of defense-related enzymes were significantly induced by W. anomalus. All these results indicated that W. anomalus has the potential to control postharvest diseases of pears, and the mechanisms involved in inhibiting spore germination and germ tube length, induction of the activities of the defense-related enzymes of pears, and improvement of the expression levels of defense-related genes of pears. [ABSTRACT FROM AUTHOR]

Highlights • Y. lipolytica significantly controlled decay caused by P. rubens of grapes. • Y. lipolytica significantly reduced OTA content produced by P. rubens of grapes. • Spore germination and germ tube length of P. rubens were inhibited by Y. lipolytica. • PPO, POD, PAL, APX, GLU and CAT activities of grapes were induced by Y. lipolytica. • The expression levels of defense-related genes were up-regulated by Y. lipolytica. Abstract Table grapes are one of the most common fruits throughout the world. Decay of grapes caused by pathogenic fungal infections results in tremendous economic losses. The aim of this study was to evaluate the effect of Yarrowia lipolytica on the control of postharvest decay of grapes caused by Penicillium rubens and the possible mechanisms involved. The results showed that Y. lipolytica provided significant inhibition of the postharvest decay of grapes by P. rubens compared with the control. When the concentration of Y. lipolytica was 1 × 109 cells/mL, decay incidence and decay diameter of grapes were 12.45% and 6.19 mm, respectively. Y. lipolytica reduced spore germination and germ tube length of P. rubens. Moreover, the results also showed that the activities of defense-related enzymes, including polyphenoloxidase (PPO), peroxidase (POD), catalase (CAT), phenylalanine ammonialyase (PAL), ascorbate peroxidase (APX) and β-1,3 glucanase (GLU),were significantly enhanced in grapes treated with Y. lipolytica. Similarly, the expression levels of these genes were also increased in grape fruits treated with Y. lipolytica. The results suggested that the possible resistance mechanism of Y. lipolytica was to enhance the defense-related enzymes and genes, ultimately reduce postharvest decay caused by P. rubens in grapes. Altogether, the research work confirmed that Y. lipolytica has potential biocontrol efficacy and could be used as a biocontrol agent to prevent the postharvest decay of grape fruits. [ABSTRACT FROM AUTHOR]

• GABA-induced S. pararoseus Y16 reduced the natural decay rate of postharvest grapes. • GABA-induced S. pararoseus Y16 retained the quality of postharvest grapes. • GABA increased the expression of stress resistance-related proteins in S. pararoseus Y16. Sporidiobolus pararoseus Y16 is a potential antagonistic yeast against various plant fungal pathogens, especially table grapes, and its biocontrol efficacy could be induced significantly by γ-aminobutyric acid (GABA). Our previous studies explored the physiological mechanisms of induced biocontrol efficacy of the yeast by GABA, but the molecular mechanisms are still unknown. This study aimed to study the effects of GABA-induced culture of S. pararoseus Y16 on natural decay and different quality parameters of table grapes; to analyze the proteomic changes of GABA-induced S. pararoseus Y16. Our results indicated that GABA-induced S. pararoseus Y16 significantly reduced the natural decay rate of postharvest grapes but retained the quality parameters, such as weight loss percentage, firmness, soluble solids, titratable acid, soluble protein and vitamin C, compared to the control group. Proteomic technology could comprehensively explain the molecular mechanism of improved biocontrol efficacy of S. pararoseus Y16 by GABA induction. The proteomic analysis of GABA-treated S. pararoseus Y16 found that there were 326 DEPs, of which 160 were up-regulated and 166 were down-regulated. KEGG pathway analysis showed that the synthesis and metabolism of deoxynucleotides pathway, citric acid cycle and related metabolism pathway, GABA shunting and lysine synthesis pathway, synthesis of terpenoids pathway and zymosterol biosynthesis pathway were associated with the enhancement of yeast biocontrol efficacy. The analysis of related metabolic pathways and other DEPs showed that GABA-treated S. pararoseus Y16 enhanced the ability of growth, reproduction, metabolism, stress resistance and amino acid synthesis of S. pararoseus Y16, thereby improving the biocontrol efficacy of the yeast. These findings can provide new ideas and methods for enhancing the biocontrol efficacy of antagonistic yeast, thus promoting the commercial application of antagonistic yeast. [ABSTRACT FROM AUTHOR]

• D. hansenii significantly reduced the incidence of postharvest soft rot of strawberry. • D. hansenii can stably colonize the surface and wounds of strawberry. • D. hansenii reduced the spore germination rate and germ tube length of R. stolonifer. • D. hansenii induced the activities of SOD, POD, CAT, APX, PPO and PAL in strawberry. • D. hansenii increased total phenolic, flavonoid and anthocyanin content in strawberry. The postharvest disease of strawberries caused by Rhizopus stolonifer caused enormous financial losses. This study investigates the efficacy of antagonistic yeast Debaryomyce hansenii in the biocontrol of postharvest soft rot of strawberries and the physiological mechanisms involved. The results showed that D. hansenii significantly reduced the incidence of postharvest soft rot of strawberry, reduced the natural decay incidence of postharvest strawberry, and had no adverse effects on quality parameters of strawberries. In vitro experiments showed that D. hansenii reduced the spore germination rate and germ tube length of R. stolonifer. D. hansenii can also stably colonize the surface and wounds of strawberries at either 4 °C or 20 °C. Meanwhile, the activities of antioxidant-related enzymes superoxide dismutase, peroxidase, catalase, ascorbate oxidase and resistance-related enzymes polyphenol oxidase and phenylalanine ammonia-lyase were significantly higher in D. hansenii -treated strawberries than in control. Meanwhile, the contents of resistance-related substances including total phenols, flavonoids and anthocyanins were also increased in D. hansenii -treated strawberries. This study suggested that D. hansenii has the potential to control postharvest soft rot of strawberry by the mechanism involving inhibition of spore germination and germ tube length of R. stolonifer and induction of increased activities of defense-related enzymes and substances in strawberry. [ABSTRACT FROM AUTHOR]

Penicillium expansum is a pathogenic fungus that causes blue mold decay in various fruits and produces toxic substances. This study investigated the effect of alginate oligosaccharide (AOS) combined with Meyerozyma guilliermondii , a biocontrol yeast, to control blue mold decay in pears and the possible physiological biocontrol mechanisms. The results showed that AOS (5 g/L) combined with M. guilliermondii could significantly reduce the blue mold decay incidence and lesion diameter of pears. Moreover, AOS did not affect the growth and reproduction of M. guilliermondii in vitro or in vivo of pears. And could inhibit mycelium development, reduce spore germination rate and inhibit the germ tube elongation of P. expansum. AOS combined with M. guilliermondii increased the activities of superoxide dismutase (SOD), catalase (CAT), polyphenol oxidase (PPO), peroxidase (POD), phenylalanine ammonia-lyase (PAL), chitinase (CHI), total phenol content, and flavonoid content in pears. Overall, our study evidenced that AOS improves the efficacy of M. guilliermondii and could be used to control the blue mold decay in pears. • M. guilliermondii combined with AOS reduced the blue mold decay of pears. • AOS had no effect on the growth and reproduction of M. guilliermondii. • AOS combined with M. guilliermondii inhibited the growth of P. expansum in vitro. • AOS with M. guilliermondii induced defense-related enzyme activities of pears. [ABSTRACT FROM AUTHOR]

• The proteomics of grapes induced by Y. lipolytica was analyzed. • The transcriptomics of grapes induced by Y. lipolytica was analyzed. • Y. lipolytica increased the expression of resistance-related proteins in grapes. • Y. lipolytica induced the expression levels of resistance-related genes in grapes. Grape berries are vulnerable to pathogen infections, during the process of harvesting and transporting, which cause tremendous economic losses. It has been reported that Yarrowia lipolytica could effectively control postharvest diseases of grapes, however, there is a very limited amount of studies available to the researchers about molecular mechanism of induced resistance. This study aimed to reveal the molecular regulation of resistance mechanism of grapes induced by Y. lipolytica , using proteomics and transcriptomics approaches. The results of the proteomics analysis of Y. lipolytica triggered grape showed that resistant related proteins involved in the process of response to stress, pathogenesis related allergenic proteins, energy production, signal transduction and oxidoreductase of grapes were all induced by Y. lipolytica and up-regulated. Similarly, transcriptomics analysis also provided the information about the up-regulation of defence related genes in grapes treated with Y. lipolytica. Meanwhile, 9 up-regulated DEGs, identified through transcriptomics analysis were selected to validate the expression levels of the genes by RT-qPCR. The DEGs include pathogenesis related allergenic proteins (PR4 , PR5 and PR10) , hypersensitivity protein, WRKY transcription factor, peroxidase isoenzyme and DEGs related to the synthesis of phytoalexin. The present study evidenced that Y. lipolytica induced and increased the expression of resistance-related proteins in grapes, which were related to response stress, energy production, signal transduction and oxidoreductase, while the expression of resistance-related genes were also up-regulated, so as to enhance the defense response of grapes against various postharvest infections. [ABSTRACT FROM AUTHOR]

Apple is one of the largely grown fruits in China, and it suffers great economic losses caused by Penicillium expansum infection every year. In the present study, we ascertained the efficacy of Meyerozyma guilliermondii enhanced by 200 μmol/L methyl jasmonate (MeJA) in controlling the postharvest blue mold decay of apples and the possible mechanisms involved. The results demonstrated that the biological control ability of M. guilliermondii induced by MeJA in restraining P. expansum infection in apples. The efficacy of M. guilliermondii induced by MeJA significantly decreased the decay incidence and lesion diameter of apples. When treated with M. guilliermondii induced by MeJA, the decay incidence of apples was only 21.6%, while apples treated with M. guilliermondii was 42.4%. M. guilliermondii induced by MeJA also reduced the germ tube length, spore germination rate of P. expansum in PDB and colony diameter of P. expansum in PDA. The results also showed that antagonistic yeast induced by MeJA proliferated better in apple wounds and surface at 4 °C or 20 °C. Meanwhile, the activities of resistance-related peroxidase (POD), polyphenol oxidase (PPO), phenylalanine ammonia-lyase (PAL), Catalase (CAT), and the antibacterial substances of flavonoid contents, total phenolic content were all increased. The results manifested that M. guilliermondii induced by MeJA increased the expression levels of defense-related enzymes in apples. • M. guilliermondii induced by MeJA decreased blue mold decay of apples. • M. guilliermondii induced by MeJA colonized in apples steadily at 20 °C and 4 °C. • M. guilliermondii induced by MeJA decreased spore germination rate of P. expansum. • M. guilliermondii induced by MeJA increased PPO, POD, CAT, PAL activities of apples. • M. guilliermondii induced by MeJA increased the expression of PPO, POD, PAL, CAT. [ABSTRACT FROM AUTHOR]

• Yarrowia lipolytica controlled postharvest diseases in mandarins effectively. • Y. lipolytica treatment had no side effects on the quality of mandarins. • Y. lipolytica inhibited growth of Penicillium digitatum and P. italicum in vitro. • Y. lipolytica colonized in wounds and on surfaces of mandarins steadily at 20 °C and 4 °C. • Defense-related enzyme activities of mandarins were induced by Y. lipolytica. Green mold and blue mold caused by Penicillium digitatum and P. italicum respectively, are two main fungal diseases in Citrus reticulata (mandarin oranges) worldwide. They are difficult to prevent for the lack of effective antagonists. This study investigated the efficacy of Yarrowia lipolytica against these diseases in mandarins and the relative defense mechanisms. The results indicated that Y. lipolytica has a great potential to inhibit the infections by P. digitatum and P. italicum in mandarins, while both the decay incidence and lesion diameter decreased in Y. lipolytica treated mandarins, in a dose-dependent manner. Furthermore, Y. lipolytica treatment had no side effects on quality paraments of mandarins. In vitro tests demonstrated that, spore germination and germ tube length of P. digitatum and P. italicum were both inhibited by Y. lipolytica. In addition, Y. lipolytica had a better ability to adapt to the environment, occupy space and utilize nutrients than pathogens, which provided a favorable condition for Y. lipolytica to colonize wounds and surfaces of mandarins. This research also showed that, Y. lipolytica induced higher activities of polyphenol oxidase (PPO), peroxidase (POD), catalase (CAT), phenylalanine ammonia lyase (PAL), and increased the contents of flavonoid compounds and total phenols, which activated the defense mechanisms of mandarins. These results suggested that Y. lipolytica is a promising antagonistic yeast to control green mold and blue mold in mandarins. [ABSTRACT FROM AUTHOR]

Wickerhamomyces anomalus is an amazing yeast with a wide range of environmental adaptability and antimicrobial properties. It has numerous biotechnological applications and is categorized as a biosafety-level-one organism that is deemed safe for individuals in good health. However, compared to the baker's yeast (Saccharomyces cerevisiae), this yeast is less studied, even though it has several commercial applications. This review aims to comprehensively explore the multifaceted attributes of W. anomalus and its potential applications in mold control and biotechnology. The characteristics of W. anomalus , the chemical compound it produces, and its efficiency against different molds and mycotoxin biodegradation are discussed in detail. Furthermore, this review highlighted diverse biotechnological applications of W. anomalus , such as its role in the production of food, beverages, fuels, and biochemicals. Finally, application strategies and future perspectives regarding the utilization of W. anomalus are discussed in detail. The majority of W. anomalus strains have been reported as a promising regulators of mold growth in food and have a wide range of biochemical and biotechnological applications. Harnessing their biocontrol and biotechnological potential through genetic engineering and synthetic biology is important. By comprehensively exploring the various facets of this attractive yeast, we hope to stimulate further research and innovation in the field, paving the way for safer and more sustainable food production practices. • W. nomalus has the ability to withstand a wide range of environmental stress. • W. anomalus can control or hinder mold growth in food. • Different strains of W. anomalus has different biotechnological applications. • W. anomalus is important in food, beverages, fuels, and biochemicals productions. [ABSTRACT FROM AUTHOR]

Soft rot caused by Pectobacterium carotovorum is one of the most serious postharvest bacterial diseases of green peppers. The present research aimed to determine the biocontrol effect of Bacillus subtilis on postharvest soft rot of green peppers and to further delve into biocontrol mechanisms by analyzing the metabolism of reactive oxygen species (ROS) in green peppers. As key results, soft rot occurrence of green peppers was alleviated with the increase of the concentration of B. subtilis , and the disease incidence and index of the fruits treated with 1 × 109 CFU/mL of B. subtilis for 4 d were 28.3% and 12.7%, respectively, which were significantly decreased compared with that of the control. B. subtilis could significantly increase NADPH oxidase (NOX) activity in green peppers to trigger ROS outbreaks, which induced defense response of the fruits. Furthermore, it promoted the enzymatic activities of the ROS scavenging system, including antioxidant enzymes (superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT)), ascorbic acid-glutathione (AsA-GSH) cycle-related enzymes (ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR)), glutathione peroxidase (GPX) cycle-related enzymes (GPX, GR and glutathione- s -transferase (GST)). Besides, B. subtilis increased the non-enzymatic ROS scavenging system contents, including ascorbate (AsA) and glutathione (GSH) in green peppers. Importantly, the levels of O 2 −·, H 2 O 2 and malondialdehyde (MDA) in green peppers were reduced, thereby enhancing green pepper disease resistance. This study offers novel insights to advanced strategies in preventing and controlling postharvest soft rot in green peppers. • B. subtilis effectively reduced postharvest soft rot of green peppers. • B. subtilis alleviated the production of O 2 ‾·, and the contents of H 2 O 2 and MDA. • NOX activity in green peppers was increased by B. subtilis. • Antioxidant enzyme activities in green peppers were stimulated by B. subtilis. • B. subtilis triggered AsA-GSH and GPX cycles, along with GST in green peppers. [ABSTRACT FROM AUTHOR]

• Baobab and S. pararoseus induced the defense enzymes of apples. • Baobab improved viability of S. pararoseus under oxidative stress. • S. pararoseus and AB induced defense-related relative gene expression of apples. The efficacy of antagonistic yeast Sporidiobolus pararoseus Y16 alone or in combination with baobab (Adansonia digitata L.) was studied for the expression levels of defense-related genes, oxidative stress and enzymes activity of apple fruits. The results revealed that the treatment of S. pararoseus Y16 at 1 × 108 cells/mL amended with baobab (AB) improved the enzyme activity and then increased the defense mechanism on apple fruit. Moreover, the results of the study showed that the combination of antagonistic yeast and AB led to an enhancement of the efficacy of enzymes of superoxide dismutase, polyphenol oxidase, peroxidase, catalase, phenylalanine ammonia lyase, and chitinase activity during the storage period. Furthermore, results showed baobab improved the oxidative tolerance of S. pararoseus Y16, which led to an enhancement of biocontrol activity of antagonist. The proper combination of S. pararoseus Y16 and baobab can thus provide an effective strategy to enhance the postharvest quality of fruits. Besides, gene expression levels of related-enzyme defense responses involved were used to investigate the mechanism of antagonistic yeast in response to the application of baobab in apple. The results exhibited that S. pararoseus Y16 amended with baobab had a significant effect on the induction of defense-related genes expression compared to the control. These findings showed that antagonist yeast treatments amended with baobab could be a promising method for enhancing defense mechanism of apple fruit. [ABSTRACT FROM AUTHOR]

Highlights • Defense-related proteins of H. uvarum were up-regulated by trehalose treatment. • Stilbene synthase of grapes was up-regulated by trehalose treated H. uvarum. • Defense enzymes of grapes were activated by H. uvarum Y3. Abstract This present study tested the extent to which 2% w/v trehalose enhanced the proteins expression profile of Hanseniaspora uvarum Y3. Furthermore, it explored the relative gene expression of stilbene synthase (StSy), one of the vital defense-related genes found in the skin of grapes. The proteomics profile revealed that 29 proteins were differentially expressed out of which 26 were significantly up-regulated and 3 were download-regulated. The pathogenesis related (PR) and other protein spots were visible at 97.4 kDa and 14.4 kDa. Peroxiredoxin TSA1 and superoxide dismutase were the main proteins involved in defense response and both proteins were significantly up-regulated. The carbohydrate and energy metabolism proteins were also significantly up-regulated. The results revealed that the treatments were associated with substantial increase in peroxidase activity compared to the control. StSy relative gene expression level was observed to increase by 2.5-fold in grapes treated with the pre-enhanced H. uvarum compared to the control. [ABSTRACT FROM AUTHOR]

This study assessed the biocontrol efficacy of Meyerozyma guilliermondii against blue mold decay caused by Penicillium expansum in pears and the possible mechanisms involved. The results indicated that M. guilliermondii significantly inhibited the blue mold decay caused by P. expansum without affecting the quality of the pears. M. guilliermondii rapidly colonized the wounds and surfaces of the pears at both 4 °C and 20 °C. The rapid growth in the population of M. guilliermondii in the wounds and surface environments of pears indicated that it has the potential to inhibit pathogens in pears. The activities of antioxidant enzymes (peroxidase and catalase) in the pear were improved after the application of the yeast. Phenylalanine ammonialyase (PAL), a key enzyme involved in lignin biosynthesis and defense related activity, was also markedly enhanced. Generally, the application of yeast induced disease resistance in the pear. The results pear proteomics profile after M. guilliermondii treatment showed that 17 proteins were significantly up-regulated and 13 were down-regulated in response to induction with M. guilliermondii . Most of the proteins were involved in defense and stress responses based on biological process. These results provided a new insight into the biocontrol mechanism of the antagonist yeast in the pear fruit. [ABSTRACT FROM AUTHOR]

In this study, the activitiesof defense-related enzymes andthose involved in reactive oxygen species (ROS) and their corresponding genes coding for PPO , APX , CHI , PAL and CAT in response to Hanseniaspora uvarum and Hanseniaspora uvarum harvested from NYDB supplemented with 2% w/v trehalose in nutrient yeast dextrose broth (NYDB) were investigated. Conventional methods and qRT-PCR were used to perform defense-related enzyme activities and relative genes expression respectively. The results indicated that H. uvarum enhanced with 2% w/v trehalose demonstrated biocontrol efficacy against Aspergillus tubingensis in grapes.Furthermore, it was noticed that H. uvarum supplemented with 2% w/v trehalose in NYDB had a significantly effect on the induction of defense-related genes expression andenzyme activities compared to the control, 2% w/v trehalose and H. uvarum after storage at 20 °C for 72 h. CAT relative gene expression level in grapes treated with H. uvarum supplemented with 2% w/v trehalose was the highest with 23-fold increase compared to the control. These results suggested that H. uvarum pretreated with trehalose up-regulatedthe defense-relatedgenes expression and enzyme activitiesin the grapes. These findings indicated that, the application of H. uvarum harvested from NYDB supplemented with 2% w/v trehalose enhanced the defense-related mechanism of grapes against A. tubingensis . [ABSTRACT FROM AUTHOR]

Abstract: The control activity of Rhodotorula mucilaginosa, alone or in combination with phytic acid (PA) on gray mold spoilage and natural spoilage of strawberries was investigated. R. mucilaginosa as stand-alone treatment significantly reduced the disease incidence of gray mold spoilage of strawberries at 20 °C, and the combination of R. mucilaginosa and PA at the concentration of 4 mol/ml and 6 mol/ml were more effective than R. mucilaginosa alone treatment. In vitro test showed that PA at the concentration of 4 mol/ml and 6 mol/ml significantly enhanced the inhibition of the growth of Botrytis cinerea on PDA. PA at all the tested concentrations enhanced the growth of R. mucilaginosa in NYDB media. PA at the concentration of 4 mol/ml slightly increased the population growth of R. mucilaginosa in strawberry wounds at the first day at 20 °C, and slightly increased the population growth of R. mucilaginosa in fruit wounds at 4 °C at the whole storage time. The combination of R. mucilaginosa and PA at the concentration of 4 mol/ml was the most effective treatment in controlling the natural spoilage of strawberries following storage at 4 °C for 20 d followed by 20 °C for 5 d. [Copyright &y& Elsevier]