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Root rot caused by Fusarium solani is one of major postharvest diseases limiting sweet potato production. Antifungal effect and possible mode of action of cinnamaldehyde (CA) against F. solani were investigated. CA concentration of 0.075 g/L inhibited conidial viability of F. solani. CA vapor of 0.3 g/L in air completely controlled the F. solani development in sweet potatoes during storage for 10 days at 28 °C, and protected soluble sugar and starch in the flesh from depletion by the fungus. Further results demonstrated that CA induced reduction in mitochondrial membrane potential (Δψ

Environmental influences are critical for the reliability of photoelectric devices, especially those using organic semiconductors. Among all the influence factors, the effect of relative humidity on the material's photoelectrical properties receives less attentions. To date, reported humidity effects are mostly related to the electrical properties. Their impact to the photoelectrical characteristics has rarely been investigated. In this work, we firstly report a detailed study on the dependency of material's photoelectrical properties on the relative humidity in photosensitive field effect transistors. It was found that both the amplitude and the decay time of the photocurrent indicated a profound dependency on the humidity. To further clarify the mechanism, experiments were carefully designed along with a simulation to recognize and to provide a detailed understanding on any possible influence factors in these processes. The results indicate a prominent co-existence of carrier-trapping and dielectric-polarization phenomena in the photoelectric device under the influences of humidity. Since the water molecules in the atmosphere are predominant, the observed variation in the photoelectrical properties can be explained.

Spice essential oils (SEOs) are commonly used in food flavoring and are considered an effective food preservative. It has a broad range of applications and promising development prospects. As a natural food additive, SEOs' antimicrobial effects have been widely studied and utilized towards food preservation. Many SEOs have exhibited significant antimicrobial activities against food-borne pathogenic and food spoilage microorganisms. We reviewed the antibacterial and antifungal properties of SEOs, the active components, their corresponding mechanisms of actions, as well as their application in the food industry, providing a theoretical basis for SEOs' further development and application as natural preservatives.

Aspergillus flavus is a common fungal pathogen of plants, animals and humans. Recently, many genes of A. flavus have been reported involving in regulation of pathogenesis in crops, but whether these genes are involved in animal virulence is still unknown. Here, we used a previous easy-to-use infection model for A. flavus based on mouse model by intravenous inoculation of A. flavus conidia. The outcome of infections in mice model showed that A. flavus NRRL3357 and laboratory strain CA14 PTS were both in dose dependent manner and highly reproducible. The progress of disease could be monitored by mice survival and histology analysis. Fungal burden analysis indicated it was gradually decreased within 7 days after infection. Moreover, aspergillosis caused by A. flavus significantly up-regulated gene expression levels of immune response mediators, including INF-γ, TNF-α, Dectin-1 and TLR2. Furthermore, the defined deletion A. flavus strains that previously displayed virulence in crop infection were also determined in this mouse model, and the results showed comparable degrees of infection in mice. Our results suggested that intravenous inoculation of conidia could be a suitable model for testing different A. flavus mutants in animal virulence. We hope to use this model to determine distinct A. flavus strains virulence in animals and study novel therapeutic methods to help control fungus diseases in the future.

Coupling the heterojunction system with surface plasmon resonance (SPR) effect is an innovative and feasible strategy to improve photocatalyst. An excellent Z-scheme CdSe-Ag-WO3-Ag photocatalyst was constructed via continuous photo-assisted process, which exhibited superior photocatalytic activity in H2 evolution (448.31 μmol•g−1 for 4 h) with simultaneous degradation of CFZ (96.32% in just 30 min) compared with CdSe-WO3, CdSe and WO3. This developed system conforms to Z-scheme electron transfer mode: CB/WO3 to Ag NPs, Ag NPs to VB/CdSe. It was verified by experiments, DFT simulation and in situ XPS characterization. So the strong reducing electron in CB/CdSe and the strong oxidizing hole in VB/WO3 were retained for H2 evolution and degradation, respectively. The coupling Ag with Z-scheme heterojunction can realize rapid electron transfer and utilization. Because the Z-scheme heterojunction inhibits recombination of carriers of the single catalyst itself and enhances electrons life, Ag acts as conductive channel to accelerate electrons transfer, and the surface defects of CdSe and Schottky barrier reduce the energy loss during the electron transmission process. This work provides new insights for boosts electron transfer to improve photocatalytic performance.

Cyclic AMP signaling controls a range of physiological processes in response to extracellular stimuli in organisms. Among the signaling cascades, cAMP, as a second messenger, is orchestrated by adenylate cyclase (biosynthesis) and cAMP phosphodiesterases (PDEs) (hydrolysis). In this study, we investigated the function of the high-affinity (PdeH) and low-affinity (PdeL) cAMP phosphodiesterase from the carcinogenic aflatoxin producing fungus Aspergillus flavus, and found that instead of PdeL, inactivation of PdeH exhibited a reduction in conidiation and sclerotia formation. However, the ΔpdeL/ΔpdeH mutant exhibited an enhanced phenotype defects, a similar phenotype defects to wild-type strain treated with exogenous cAMP. The activation of PKA activity was inhibited in the ΔpdeH or ΔpdeL/ΔpdeH mutant, both of whom exhibited increasing AF production. Further analysis by qRT-PCR revealed that pdeH had a high transcriptional level compared to pdeL in wild-type strain, and affected pdeL transcription. Green fluorescent protein tagging at the C-terminus of PDEs showed that PdeH-GFP is broadly compartmentalized in the cytosol, while PdeL-GFP localized mainly to the nucleus. Overall, our results indicated that PdeH plays a major role, but has overlapping function with PdeL, in vegetative growth, development and AF biosynthesis in A. flavus.

Ceratocystis fimbriata is the most devastating phytopathogen causing significant losses in post-harvest sweet potato. In this study, monoterpene nerol (NEL), the active compound in neroli essential oil, was found to dose-dependently inhibit the mycelial growth and spore germination of C. fimbriata at a minimum inhibitory concentration (MIC) of 0.25 mL L-1. NEL vapor treatments significantly reduced the incidence and lesion diameter of black rot in sweet potato infected by the fungus and regulated the defense-related enzyme activity of phenylalanine ammonia lyase (PAL). Using RNA sequencing (RNA-seq) and biochemical assays, it was demonstrated that NEL treatment impaired cell membrane integrity via down-regulating the expression of ergosterol synthesis genes and reduced the ergosterol content. Moreover, an analysis of a series of apoptotic events revealed that NEL treatment caused mitochondrial membrane damage by reducing the mitochondrial membrane potential (MMP, Δψm), which led to down-regulation of genes involved in ATP production, then induced accumulation of intracellular reactive oxygen species (ROS) generation. Simultaneously, NEL caused nuclear chromatin condensation and concomitant DNA cleavage, which led to the up-regulation of DNA repair genes expression, and the cell-cycle arrest principally occurred at the G2/M phase in C. fimbriata. Altogether, these findings provide information about the underlying antifungal mechanism of NEL against C. fimbriata and suggest that NEL could be a useful alternative for controlling C. fimbriata in post-harvest spoilage of sweet potato.

Perillaldehyde (PAE), a natural monoterpenoid agent extracted from Perilla frutescence, PAE has been reported to present various physiological capabilities, such as anti-inflammation, anti-oxidative and anti-fungal. In this study, we show that PAE exhibits strong antifungal activity against Candida albicans (C. albicans). C. albicans, a fungal pathogen with high incidence of antifungal resistance in clinical settings, is the major cause of oropharyngeal candidiasis (OPC). OPC is characterized by inflammatory immunological responses to fungal infections. Our in vitro results show PAE inhibited several virulence attributes of C. albicans including biofilm formation, yeast-to-hyphal transition and secreted aspartic proteinases (SAPs) gene expression. Using an experimental murine model of OPC, we found that PAE inhibited NLRP3 inflammasome assembly, reduced the excessive accumulation of ROS and prevented the p65 transfer in nuclear; processes all leading to reduced inflammation burden in the host. Together, this supports use PAE as a promising new agent to improve OPC.

Ochratoxin A (OTA) is a ubiquitous food contaminant and a critical food safety concern due to its nephron toxic effects, which impacts all parts of the world. Luteolin (LUT) had gained increasing interest as a health-promoting food antioxidant component. However, the preventative effect of LUT against OTA induced oxidative stress was not yet clear and the elucidation of which would provide critical information to develop dietary LUT as a control strategy for OTA. In the current study, the cytoprotective effect of LUT against OTA induced oxidative stress and the mechanism(s) behind was examined in NRK-52E rat kidney cells. The results showed that LUT exerted its preventative effect via restoring cell viability and preventing LDH release. It alleviated the OTA-induced oxidative stress and lipid peroxidation by reducing ROS accumulation, ameliorating the mitochondrial membrane potential reduction and reversing the activities of antioxidant enzymes to the control levels. The regulating roles of Nrf2 and HIF-1α in this process were evaluated by cell immunofluorescence assay, reporter plasmids transfection assay and qRT-PCR analysis. The results showed that LUT activated Nrf2 pathway and increased the antioxidant defense capacities of OTA treated cells. Additionally, LUT also modulated HIF-1α pathway to initiate the angiogenesis and epithelial restitution process.

The chemical composition and antioxidant and antifungal activities of hydro-distilled essential oils (EOs) in black and white Piper nigrum L were evaluated in the present study. Hydro-distilled EOs obtained from black and white P. nigrum L from five areas of China was analyzed by gas chromatography-mass spectrometry (GC-MS). Nineteen compounds were identified, accounting for 98.20–99.35% of the oils. Chemical variation in the oils was estimated using systematic cluster analysis and principal component analysis. Moreover, antioxidant activity was determined by DPPH and ABTS radical cation scavenging assay, ferric reducing power assay, and ferric ion chelating activity assay, scavenging superoxide anion free radical activity assay and antifungal activity were assessed by micro-well dilution assay. Our results suggest that the region of origin greatly influences the pepper's chemical composition and bioactivities, which might support the development and utilization of this promising bio-resource in food industries.

Small non-coding RNA (sRNA) in various organisms remains a mysterious subject. Although microRNAs (miRNAs) have been intensively investigated in plants and animals, the study of miRNAs in fungi has been limited. Only microRNA-like RNAs (milRNAs) have been reported in several filamentous fungi. In this study, Illumina deep sequencing was performed to characterize the sRNA in Aspergillus flavus and to evaluate their responses to water activity and temperature. Global expression analysis showed an extensively differential expression of sRNA loci in A. flavus under different temperature or water activities. In addition, a total of 135 milRNAs were identified in A. flavus. The milRNA profiles obtained in deep sequencing were further validated by RT-qPCR assay. The presence and differential expression of milRNAs under different temperature or water activities in A. flavus imply that milRNAs might play important roles in the mycotoxin biosynthesis and mycelium growth in fungi A. flavus.

The phases, microstructure, and magnetic properties of Co80Zr18−xNbxB2 (x=1, 2, 3, and 4) melt-spun ribbons were investigated. The small substitution of Nb for Zr in the Co–Zr–B melt-spun ribbons resulted in the improvement of magnetic properties, especially the coercivity. The main effect of added Nb on the coercovity of Co–Zr–Nb–B melt-spun ribbons, originated from modification of the grain size of Co11Zr2 phase. The coercivity of the Co–Zr–Nb–B melt-spun ribbons depends on the annealing temperature. The optimal magnetic properties of Hc=5.1 kOe, and (BH)max=3.4 MGOe were obtained in the Co80Zr15Nb3B2 melt-spun ribbons annealed at 600 °C for 3 min.