A new diketopiperazine-type alkaloid from the endophytic fungus Penicillium expansum.

A chemical investigation on an endophytic fungus Penicillium expansum isolated from the medicinal plant Plantago depressa Willd. (Plantaginaceae) afforded one new diketopiperazine-type alkaloid, namely penicimine A (1), as well as two known congeners (2 and 3). Their structures were elucidated by widespread spectroscopic data, and the absolute configurations of 1 and 2 were further confirmed by single-crystal X-ray diffraction analyses. Compound 1 represented the first example of benzyl-containing diketopiperazine-type alkaloid bearing a methyl group attached at C-15 position. Compound 1 showed anti-inflammatory activity against LPS-induced nitric oxide (NO) production in RAW264.7 mouse macrophages with an IC50 value of 25.65 µM.

Biomedical Applications of Mycosynthesized Selenium Nanoparticles Using Penicillium expansum ATTC 36200.

In this study, green and eco-friendly biosynthesis of selenium nanoparticles (Se-NPs) were performed using Penicillium expansum ATTC 36200 for multiple biomedical applications. Mycosynthesized Se-NPs were completely characterized using UV, FT-IR, XRD, SEM, and TEM techniques. Se-NPs biosynthesized by P. expansum was characterized as a spherical shape with average size 4 to 12.7 nm. Moreover, Se-NPs were evaluated for multiple biomedical applications as antimicrobial, antioxidant, and anticancer activities and hemocompatibility. Results illustrated that Se-NPs have potential antimicrobial activity against Gram-positive (Bacillus subtilis ATCC6051 and Staphylococcus aureus ATCC23235), Gram-negative bacteria (Escherichia coli ATCC8739and Pseudomonas aeruginosa ATCC9027), fungi (Candida albicans ATCC90028, Aspergillus niger RCMB 02724 and Aspergillus fumigatus RCMB 02568), and antioxidant activity. Additionally, Se-NPs exhibited anticancer activity against PC3 cell line; IC50 was 99.25 µg/mL. Meanwhile, they showed non-hemolytic activity on human RBCs at concentration up to 250 µg/mL. In conclusion, biosynthetic Se-NPs by P. expansum are promising for many safe-use biomedical applications.

[Fermentation of cellulase with multiple types of Salvia miltiorrhiza residues and other solid wastes from Chinese materia medica industrialization].

The solid wastes of Chinese materia dedica industrialization represented by Salvia miltiorrhiza residues have a strong small-molecule bio-recalcitrance in the process of high-value utilization of biotransformation. Highly tolerant strains were bred to break bio-recalcitrance of Salvia miltiorrhiza residues and produce high-value added cellulose, which has a significant significance for recycling and industrial utilization of solid waste. In this study, a strain of fungus, Penicillium expansum SZ13, was found with small-molecule antibacterial substance tanshinone contained in Salvia miltiorrhiza residues by a biological method. The optimal enzyme production process and peak period of SZ13 were determined. It was found that SZ13 could maintain peak enzyme production for 5 days by degrading residues under the conditions of temperature 35 ℃, rotation speed 180 r·min~(-1), 5% of residues addition, and 5% seed solution addition. Meanwhile, the ability of SZ13 to degrade the enzyme production of multiple types of residues was explored. The results showed a high enzyme activity and stable enzyme production of SZ13 in the process of degrading residues. SZ13 could efficiently utilize various types of Chinese medicine residues, such as Salvia miltiorrhiza residues, to realize the high-value utilization of cellulose in multiple types of residues.

Effect of benzothiadiazole treatment on improving the mitochondrial energy metabolism involved in induced resistance of apple fruit during postharvest storage.

The effects of benzothiadiazole (BTH) on Penicillium expansum development, mitochondria energy metabolism, and changes in the number and structure of mitochondria in apple fruit were investigated after the fruit were immersed in 100 mg L-1 BTH for 10 min and then stored at 22 °C. The results indicated that BTH treatment significantly decreased the lesion diameter of fruit challenged with P. expansum; further, treatment enhanced the activities of mitochondrial respiratory metabolism-related enzymes, such as succinate dehydrogenase, cytochrome oxidase, H+-ATPase and Ca2+-ATPase, along with high ATP level and energy status in apple fruit during storage. Moreover, transmission electron microscopy results indicated that BTH treatment was beneficial for maintaining the number and structure of mitochondria during storage. The results suggested that BTH treatment enhanced ATP levels via mitochondrial energy metabolism, which might contribute to the induced resistance in apple fruit during storage.

Fermentation of cellulase with multiple types of Salvia miltiorrhiza residues and other solid wastes from Chinese materia medica industrialization / 中国中药杂志

The solid wastes of Chinese materia dedica industrialization represented by Salvia miltiorrhiza residues have a strong small-molecule bio-recalcitrance in the process of high-value utilization of biotransformation. Highly tolerant strains were bred to break bio-recalcitrance of Salvia miltiorrhiza residues and produce high-value added cellulose, which has a significant significance for recycling and industrial utilization of solid waste. In this study, a strain of fungus, Penicillium expansum SZ13, was found with small-molecule antibacterial substance tanshinone contained in Salvia miltiorrhiza residues by a biological method. The optimal enzyme production process and peak period of SZ13 were determined. It was found that SZ13 could maintain peak enzyme production for 5 days by degrading residues under the conditions of temperature 35 ℃, rotation speed 180 r·min~(-1), 5% of residues addition, and 5% seed solution addition. Meanwhile, the ability of SZ13 to degrade the enzyme production of multiple types of residues was explored. The results showed a high enzyme activity and stable enzyme production of SZ13 in the process of degrading residues. SZ13 could efficiently utilize various types of Chinese medicine residues, such as Salvia miltiorrhiza residues, to realize the high-value utilization of cellulose in multiple types of residues.

The response of growth and patulin production of postharvest pathogen Penicillium expansum to exogenous potassium phosphite treatment.

In this study, the effects of exogenous potassium phosphite (Phi) on growth and patulin production of postharvest pathogen Penicillium expansum were assessed. The results indicated that P. expansum under 5mmol/L Phi stress presented obvious development retardation, yield reduction of patulin and lower infectivity to apple fruit. Meanwhile, expression analysis of 15 genes related to patulin biosynthesis suggested that Phi mainly affected the early steps of patulin synthetic route at transcriptional level. Furthermore, a global view of proteome and transcriptome alteration of P. expansum spores during 6h of Phi stress was evaluated by iTRAQ (isobaric tags for relative and absolute quantitation) and RNA-seq (RNA sequencing) approaches. A total of 582 differentially expressed proteins (DEPs) and 177 differentially expressed genes (DEGs) were acquired, most of which participated in carbohydrate metabolism, amino acid metabolism, lipid metabolism, genetic information processing and biosynthesis of secondary metabolites. Finally, 39 overlapped candidates were screened out through correlational analysis between iTRAQ and RNA-seq datasets. These findings will afford more precise and directional clues to explore the inhibitory mechanism of Phi on growth and patulin biosynthesis of P. expansum, and be beneficial to develop effective controlling approaches based on Phi.

Use of oil-in-water emulsions to control fungal deterioration of strawberry jams.

This work aimed to control the fungal deterioration of strawberry jams. The antifungal activity of the clove, cinnamon leaf, lemon and mandarin essential oils and their effectiveness in oil-in-water emulsions were evaluated. According to the results obtained, only clove and cinnamon leaf oils were selected to prepare emulsions. All the tested emulsions were stable, independently the amount of polymer and essential oil used. Essential oil loss was affected by the amount of polymer employed to prepare the emulsions. The oil-in-water emulsions with 5.0mg/g xanthan gum, and with 0.55mg/g clove or 0.65mg/g cinnamon leaf essential oil, were used for the in vivo tests. The jams prepared with the oil-in-water emulsions showed a lower fungal decay compared with jams without emulsion. The present work demonstrated that emulsions can be employed to prevent strawberry jam mould spoilage.

The effect of chitosan and whey proteins-chitosan films on the growth of Penicillium expansum in apples.

BACKGROUND: Penicillium expansum causes a major post-harvest disease of apples. The aim of this study was to investigate the inhibition effect of chitosan and whey proteins-chitosan films containing different amounts of quince and cranberry juice against P. expansum on the simulation medium and on apples. The mechanical properties of films were also evaluated. RESULTS: The presence of cranberry and quince juice in the composition of chitosan and whey proteins-chitosan films caused a significant (P ≤ 0.05) increase in elasticity and decrease in tensile strength of films. Chitosan and whey proteins-chitosan films with quince and cranberry juice demonstrated a significant (P ≤ 0.05) inhibition effect against P. expansum growth on the simulated medium and apples. The presence of cranberry juice in the composition of chitosan and whey proteins-chitosan films resulted in a longer lag phase and a lower P. expansum growth rate on the simulation medium in comparison with films made with the addition of quince juice. These differences were not evident when experiment was conducted with apples. CONCLUSION: Addition of quince and cranberry juice to the chitosan and whey proteins-chitosan films as natural antifungal agents has some potential for prolonging the shelf life of apples.

Characterization of the 5' flanking region of lipase gene from Penicillium expansum and its application in molecular breeding.

A major challenge for further promotion of lipase productivity in Penicillium expansum PE-12 is to find a suitable promoter that can function efficiently in this industrial strain. In this study, the 5' flanking region of P. expansum lipase (Ppel) containing a putative novel promoter sequence was characterized by fusing to ß-glucuronidase (GUS) and subsequently introducing into P. expansum. As a result, all the transformants showed blue color quickly after incubation in GUS detection buffer, suggesting a strong promoter activity of this fragment. Glucose repression was identified for the promoter, whereas olive oil acted as a positive regulator. Facilitated by this novel promoter, P. expansum PE-12 was genetically modified, with an improved lipase yield, via a recombinant plasmid with P. expansum lipase gene (PEL) under the control of Ppel promoter and TtrpC terminator. The highest lipase yield among the modified strains could attain 2,100 U/mL, which is more than twofold of the previous industrial strain (900 U/mL). The engineered strain through molecular breeding method as well as this new promoter has great value in lipase industry.