Fungal Genera Research Articles

The Ecological Strategy Determines the Response of Fungi to Stress: A Study of the 2,4-diacetylphloroglucinol Activity Against Aspergillus and Fusarium Species.

Aspergillus and Fusarium are two economically important genera of fungi. They cause significant yield losses and contamination of crops with mycotoxins. In this study we aimed to evaluate the impact of 2,4-diacetylphloroglucinol (2,4-DAPG) on Aspergillus and Fusarium fungi. It is hypothesized that two fungal genera, which have different ecological strategies, react differently to stress caused by a secondary metabolite produced by rhizosphere Pseudomonas species. We found that 2,4-DAPG was able to reduce biofilm formation of Aspergillus and Fusarium, as reflected in biomass and its chemical composition. Furthermore, subinhibitory concentrations of 2,4-DAPG increased the levels of ergosterol and polysaccharides (α- and β-glucans, chitin) in the cell membrane and cell wall of Aspergillus, while decreasing them in Fusarium. 2,4-DAPG altered the production of secondary metabolites, especially mycotoxins and extracellular proteases. The production of ochratoxin A was decreased in A. ochraceus, and T-2 toxin and zearalenone, on the contrary, were increased in F. culmorum and F. sporotrichioides, respectively. Thus, using 2,4-DAPG we demonstrated that the ecological role of fungi determines their reaction to antibiotic substances produced by the plant microbiome. Our data contributes to understanding the molecular mechanisms behind symbiotic relationships in natural communities, which are mediated by the biosynthesis of antibiotics.

Rare bacterial and fungal taxa respond strongly to combined inorganic and organic fertilization under short-term conditions

Soil microbial communities play a crucial role in driving multiple ecosystem functions. Although numerous studies have investigated the effects of fertilization on the entire soil microbial community, the responses of abundant (relative abundance ≥ 1 % in all samples, or ≥ 1 % in some samples but never < 0.01 % in any samples) and rare (relative abundance < 0.01% in all samples, or < 0.01% in some samples but never≥ 1% in any samples) microbial taxa, as along with their relative contributions to ecosystem functions in agricultural soils under combined organic and inorganic fertilization, have been less explored. Here, a field experiment revealed that rare bacterial and fungal taxa were more sensitive to short-term fertilization than abundant taxa. The combined application of inorganic and organic fertilizers maintained the alpha-diversity of rare bacterial taxa and enhanced the alpha-diversity of rare fungal taxa. The significant impact of fertilization on the bacterial community was primarily induced by alterations in soil pH (decreased from 6.01 to 5.46), total phosphorus (0.32 – 0.37 g/kg), available phosphorus (1.24 – 4.76 mg/kg), and available potassium (41.11 – 58.78 mg/kg), whereas the fungal community was less influenced by fertilization. The dissimilarity of both abundant (Mantel r = 0.38, P = 0.001) and rare (Mantel r = 0.26, P = 0.014) bacterial taxa exhibited positive relationships with ecosystem multifunctionality. Additionally, ecosystem multifunctionality was positively associated with the relative abundance of specific genera and keystone species, particularly rare bacterial taxa (e.g., Melioribacter, Aquisphaera, Sunxiuqinia, Methylobacterium, and Thermosporothrix), the abundant fungal genus Achroiostachys, and rare fungal taxa (e.g., Paraphelidium, Pseudallescheria, Scutellinia, Niesslia, Tilletia, Coprinopsis, Poaceascoma, Entrophospora sp., Acremonium persicinum, Hydropisphaera erubescens, and Rozellomycota sp.) (ρ = 0.52–0.75, P < 0.05). A partial least-squares path model indicated that soil nutrients (path coefficient = 0.83, p = 0.001) and microbial beta-diversity (path coefficient = 0.18, p = 0.049) exerted primary direct and positive effects on ecosystem multifunctionality, with soil nutrients also indirectly influencing ecosystem multifunctionality through microbial beta-diversity. Collectively, these findings underscore the significant response of rare, rather than abundant, microbial taxa and their contributions to ecosystem multifunctionality. This highlights the potential of appropriately combined inorganic and organic fertilizers, which promote rare microbial taxa, to enhance the multifunctionality of agricultural ecosystems.

Assessment of bacterial and fungal contamination of herbal mixture vended within Kaduna metropolis, Nigeria

The consumption of herbal mixtures among Nigerians have been on the increase in recent years. Many herbal mixtures sold to the general public are likely to be contaminated by a diverse range of potentially pathogenic microorganisms due to lack of good manufacturing practices (GMPs). Therefore, this study is aimed to evaluate the bacterial and fungal profile of herbal mixtures sold within the Kaduna metropolis. A total of twenty samples of herbal mixtures were randomly purchased fromfour distinct locations within the Kaduna metropolis. The samples were subjected to microbiological analysis using standard methods. Bacterial genera isolated from the herbal mixture samples include Bacillus sp., Staphylococcus sp., Streptococcus sp. while the fungal genera were Aspergillus sp., Saccharomyces sp., Fusarium sp. and Penicillium sp. Herbal mixture obtained from Mandao and Malali district had the highest (9.68±1.70×105CFU/ml) and lowest (6.60±0.43×105CFU/ml) bacterial load while the corresponding fungal load involved samples obtained from Central market (1.48±11.25×104 CFU/ml) and Tudun Wada (1.48± 3.11 ×103 CFU/ml), respectively. Bacillus sp. (60%) and Aspergillus sp. (45%) were the dominant bacterial and fungal genera, respectively. Given the substantial microbial contamination of herbal mixtures and the potential pathogenicity of certain isolates, it is imperative to ensure that herbalists are wellinformed about the principles and implementation of GMPs. It is recommended that regular microbiological monitoring of herbal mixtures should be conducted.

Identification of hub genes and potential networks by centrality network analysis of PCR amplified Fusarium oxysporum f. sp. lycopersici EF1α gene

BackgroundFusarium wilt is a devastating soil-borne fungal disease of tomato across the world. Conventional method of disease prevention including usage of common pesticides and methods like soil solarisation are usually ineffective in the treatment of this disease. Therefore, there is an urgent need to identify virulence related genes in the pathogen which can be targeted for fungicide development.ResultsPathogenicity testing and phylogenetic classification of the pathogen used in this study confirmed it as Fusarium oxysporum f. sp. lycopersici (Fol) strain. A recent discovery indicates that EF1α, a protein with conserved structural similarity across several fungal genera, has a role in the pathogenicity of Magnaporthe oryzae, the rice blast fungus. Therefore, in this study we have done structural and functional classification of EF1α to understand its role in pathogenicity of Fol. The protein model of Fol EF1α was created using the template crystal structure of the yeast elongation factor complex EEF1A:EEF1BA which showed maximum similarity with the target protein. Using the STRING online database, the interactive information among the hub genes of EF1α was identified and the protein–protein interaction network was recognized using the Cytoscape software. On combining the results of functional analysis, MCODE, CytoNCA and CytoHubba 4 hub genes including Fol EF1α were selected for further investigation. The three interactors of Fol EF1α showed maximum similarity with homologous proteins found in Neurospora crassa complexed with the known fungicide, cycloheximide. Through the sequence similarity and PDB database analysis, homologs of Fol EF1α were found: EEF1A:EEF1BA in complex with GDPNP in yeast and EF1α in complex with GDP in Sulfolobus solfataricus. The STITCH database analysis suggested that EF1α and its other interacting partners interact with guanosine diphosphate (GDPNP) and guanosine triphosphate (GTP).ConclusionsOur study offers a framework for recognition of several hub genes network in Fusarium wilt that can be used as novel targets for fungicide development. The involvement of EF1α in nucleocytoplasmic transport pathway suggests that it plays role in GTP binding and thus apart from its use as a biomarker, it may be further exploited as an effective target for fungicide development. Since, the three other proteins that were found to be tightly associated Fol EF1α have shown maximum similarity with homologous proteins of Neurospora crassa that form complex with fungicide- Cycloheximide. Therefore, we suggest that cycloheximide can also be used against Fusarium wilt disease in tomato. The active site cavity of Fol EF1α can also be determined for computational screening of fungicides using the homologous proteins observed in yeast and Sulfolobus solfataricus. On this basis, we also suggest that the other closely associated genes that have been identified through STITCH analysis, they can also be targeted for fungicide development.

Multi-omics analysis reveals the effects of host-rumen microbiota interactions on growth performance in a goat model.

The growth rate of young ruminants has been associated with production performance in later life, with recent studies highlighting the importance of rumen microbes in supporting the health and growth of ruminants. However, the specific role of rumen epithelium bacteria and microbiota-host interactions in influencing the early life growth rate of ruminants remains poorly understood. In this study, we investigated the rumen fermentation pattern, microbiota characteristics, and global gene expression profiles of the rumen epithelium in 6-month-old goats with varying growth rates. Our results showed that goats with high average daily gain (HADG) exhibited higher rumen propionate concentrations. Goats with low average daily gain (LADG) had the higher relative abundances of rumen epithelium bacteria genera U29-B03 and Quinella, while exhibiting a lower relative abundance of Lachnospiraceae UCG-009. In the rumen fluid, the relative abundances of bacteria genus Alloprevotella were lower and Desulfovibrio were higher in LADG goats compared to HADG goats. Additionally, the relative abundance of fungal genus Symmetrospora was lower in LADG goats compared to HADG goats. Transcriptome analysis showed that 415 genes were differentially expressed between LADG and HADG goats, which were enriched in functions related to cell junction and cell adhesion, etc. Correlation analysis revealed that rumen epithelium bacteria genera UCG-005 and Candidatus Saccharimonas were negatively associated, while Lachnospiraceae NK3A20 group and Oscillospiraceae NK4A214 group were positively associated with average daily gain (ADG) and genes related to barrier function. The rumen fluid bacteria genus Alloprevotella was positively correlated, while Desulfovibrio was negatively correlated with rumen propionate and ammoniacal nitrogen (NH3-N) concentrations, as well as genes related to barrier function and short chain fatty acids (SCFAs) transport. In summary, our study reveals that the higher ruminal fermentation efficiency, improved rumen epithelial barrier functions, and enhanced SCFAs transport in HADG goats could be attributed to the rumen microbiota, particularly the rumen epithelium bacteria, such as Lachnospiraceae and Oscillospiraceae NK4A214 group.

Comparative Analysis of Microbial Communities in Diseased and Healthy Sweet Cherry Trees (Prunus avium L.).

The European sweet cherry Prunus avium (L.), a member of the Rosaceae family, is one of the most popular and economically valuable fruits. However, the rapid spread of gummosis and poor management practices have become the major obstacles to their production. To identify pathogenic microorganisms responsible for gummosis disease, we conducted observations comparing the garden of Bailuyuan, which heavily suffered from gummosis disease and horn beetle damage, with the orchard of Mayuhe, which only suffered from gummosis disease, both from Xi'an, Shaanxi, China. Samples were obtained from the healthy tissues and gummosis disease tissues that used the Illumina sequence of 16S rRNA and the internal transcribed spacer region (ITS) to identify bacterial and fungal communities in these samples. An alpha diversity analysis revealed a significantly higher fungal diversity of disease than in healthy tissue in the gummosis period. The results suggested that an imbalance in the fungal genera may be associated with gummosis disease. Species relative analyses showed some bacterial genera (Pelagibacterium, Halomonas, Azospirillum, Aquabacterium and Alistipes) and fungal genera (Penicillium, Alternaria and Rhodotorula) in the diseased tissues of gummosis. Among these, the increased relative abundance of the bacteria genes Halomonas, Pelagibacterium, Chelativorans, Pantoea, Aquabacterium, Alternaria and fungi genes Penicillium, Cystobasidium, Rhodotorula may be associated with gummosis of P. avium. The bacterial genera Methylobacterium, Psychroglaciecola, Aeromonas, Conexibacter and fungal genera Didymella, Aureobasidium, Mycosphaerella, Meyerozyma are probably antagonists of the pathogen of gummosis. These findings are an initial step in the identification of potential candidates for the biological control of the disease.

Beyond morphogenesis and secondary metabolism: function of Velvet proteins and LaeA in fungal pathogenesis.

Velvet proteins, as well as the epigenetic regulator LaeA, are conserved in numerous fungal species, where, in response to environmental cues, they control several crucial cellular processes, including sexual and asexual morphogenesis, secondary metabolism, response to oxidative stress, and virulence. During the last two decades, knowledge of their mechanism of action as well as understanding their functional roles, has greatly increased, particularly in Aspergillus species. Research efforts from multiple groups followed, leading to the characterization of other Velvet and LaeA homologs in species of other fungal genera, including important opportunistic plant and animal pathogens. This review focuses mainly on the current knowledge of the role of Velvet and LaeA function in fungal pathogenesis. Velvet proteins and LaeA are unique to fungi, and for this reason, additional knowledge of these critical regulatory proteins will be important in the development of targeted control strategies to decrease the detrimental impact of fungal pathogens capable of causing disease in plants and animals.

Investigating the Ochratoxin Production Potential of Aspergillus spp in Indian Rice: A Comprehensive Study

Rice (Oryza sativa), world’s second most important cereal crop and most commonly consumed grains in the world. Though more than 100,000 species of fungi are known to exist, majority of mycotoxigenic fungi belong to the species of Aspergillus, Penicillium, and Fusarium. Among Aspergillus spp, Aspergillus niger and Aspergillus ochraceus are known to produce Ochratoxin A (OTA), a notable mycotoxin having adverse effects due to ubiquitous presence, renal toxicity and lengthy persistence. Totally eighty-one samples including unpolished (n = 36) and polished rice samples (n = 45) were collected in various districts of Tamil Nadu to identify ochratoxigenic fungi particularly Aspergillus spp. Out of 81 samples, 62 % (50/81) of samples including unpolished (n = 24) and polished rice (n = 26) documented the occurrence of ochratoxigenic fungi. Extraction of OTA was carried out by agar plug method and the ability of fungus to produce OTA was quantified by RP HPLC-FLD analysis. Among the fungal genera, Aspergillus spp (80 %) recorded the predominant fungus in rice. Molecular confirmation of ochratoxigenic fungi A. niger and A. ochraceus isolates was performed by 18s rDNA analysis. OTA producing ability by RP HPLC-FLD analysis revealed A. ochraceus of section Circumdati recorded the highest OTA production than A. niger isolates of section Nigri. The concentration range of OTA by A. ochraceus vary between 12.33 - 196.84 ng/g and 0.18 - 2.82 ng/g respectively in A. niger isolates. Among the A. ochraceus isolates, potent isolate AO 9 documented the highest OTA production (196.84 ng/g) followed by AO 6 (104.74 ng/g). Similarly, in A. niger AN 1 showed highest production of 2.82 ng/g followed by AN 5 isolate (1.25 ng/g) respectively. The objective of the study is to determine and quantify the ochratoxin production potential of Aspergillus spp in Indian rice by RP HPLC-FLD analysis. The occurrence of Aspergillus spp in rice and the subsequent ochratoxin production raise concern about possible health risk to animal and human environment upon consumption. Hence there is need for improved storage practices and regular monitoring to prevent the prevalence of Aspergillus fungus and OTA contamination in rice supply chain.

FUNGAL FLORA OF ROSETTE QUILLS IN THE NORTH AMERICAN PORCUPINE (ERETHIZON DORSATUM) IN THE NORTHEASTERN UNITED STATES.

The North American (NA) porcupine (Erethizon dorsatum) is a rodent species with specialized hair structures called quills designed to detach and penetrate into tissues of any human or animal coming into contact with them. The objective of this study was to characterize the fungal flora of the quills in the region of the rosette in wild NA porcupines to further define health risks to NA porcupines and any animal coming into contact with the quills. A total of 17 adult NA porcupines were sampled, and fungal culture was performed. Fungal organisms were cultured from 15 (88.2%) of 17 samples. Thirty-three isolates of 10 different fungal genera were cultured. The most frequently isolated fungi were Lodderomyces elongisporus (n = 7, 41.2%), Candida spp. (n = 3, 17.6%), and Penicillium spp. (n = 2, 11.8%). Eleven (64.7%) individuals grew multiple fungal organisms. In humans and animals quilled by porcupines, fungal culture should be considered in cases of infection, and if isolates resembling Candida spp. are isolated, matrix-assisted laser desorption-ionization time of flight or molecular methods are necessary to rule out L. elongisporus.

Efficacy of Postharvest Application of Aureobasidium pullulans to Control White Haze on Apples and Effect on the Fruit Mycobiome

White haze, an emerging disorder caused by extensive fungal growth on the apple surface, results in a compromised fruit quality and decreased marketability. The use of biological control agents could be an interesting tool to reduce its development. This work aimed to test the efficacy of two Aureobasidium pullulans strains (AP2 and PL5) in controlling white haze on stored apples. An in vivo trial was conducted by inoculating fruits with white haze causal agents (Entyloma belangeri, Golubevia pallescens, Tilletiopsis washingtonensis) and treating them with the antagonistic yeasts. Three commercial biofungicides were also included in the trial. Both A. pullulans strains, along with the Metschnikowia fructicola-based product, reduced white haze incidence after 110 days of storage at 1 ± 1 °C and after 7 days of shelf life. Furthermore, the effect of A. pullulans application on the fruit fungal microbiome was assessed. A significant impact of apple matrix and treatment on the mycobiome composition was observed. Analyses showed a good colonization of A. pullulans on the treated apples, both epiphytically and endophytically. A decrease in white haze-related fungi abundance was observed in the treated fruits. Additionally, a reduction of Ramularia spp. and modifications in the abundance of other fungal genera were detected after storage and shelf life.

Culture-Independent Characterization of Citrus Rhizospheric Bacterial and Fungal Microbiota from Piura, Peru

The “limón sutil” (Citrus aurantifolia) has been widely cultivated and well established for many years in Piura, northwestern Peru, because of its exceptional climate and soil conditions. However, decline and death of C. aurantifolia trees caused by different phytopathogens remain a common problem which has been observed in the last decades. It is known that the microbiota of soil plays an important role with their host and could be the starting point to understand the causes of citrus decline. In this study, we identified through culture-independent methods the bacterial and fungal microbiota associated to C. aurantifolia, C. jambhiri and C. volkameriana rhizospheres in the main areas of Piura. By using a 16S rRNA and ITS-metabarcoding analysis, we evaluated the taxonomic diversity between healthy trees and with decline symptoms and how this diversity could influence the health status of citrus trees. More than 600 and 200 bacterial and fungal ASVs were identified, respectively. Our metabarcoding analysis was able to identify Proteobacteria, Cyanobacteria, Firmicutes, Bacteroidota and Acidobacteriota prokaryotic phyla, while fungal phyla included Ascomycota, Basidiomycota and Glomeromycota. In addition, there were differences between microbial diversity indices in rhizospheres evaluated. Finally, bacterial and fungal genera were shared among the different citrus rhizospheres. These results have allowed us to obtain a preliminary identification of microbiota in the citrus rhizospheres of healthy trees and with decline symptoms.

Effect of Organic and Chemical Fertilizer on the Diversity of Rhizosphere and Leaf Microbial Composition in Sunflower Plant.

Applying organic manure to crops positively impacts the soil microbial community which is negatively impacted when chemical fertilizers are used. Organic manures also add new microbes to the soil in addition to influencing the growth of native ones. Metagenomic analysis of different organic manures, soil, and pot culture experiments conducted under various fertilizer conditions constitute the primary methodologies employed in this study. We compared the effect of two organic manure combinations and an inorganic fertilizer combination on microbial community of rhizosphere soil and leaves of sunflower plants. Metagenomic sequencing data analysis revealed that the diversity of bacteria and fungi is higher in organic manure than in chemical fertilizers. Each organic manure combination selectively increased population of some specific microbes and supported new microbes. Application of chemical fertilizer hurts many plant beneficial fungi and bacteria. In summary, our study points out the superiority of organic manure combinations in enhancing microbial diversity and supporting beneficial microbes. These findings enhance the profound influence of fertilizer types on sunflower microbial communities, shedding light on the intricate dynamics within the rhizosphere and leaf microbiome. Bacterial genera such as Bacillus, Serratia, Sphingomonas, Pseudomonas, Methylobacterium, Acinetobacter, Stenotrophomonas, and fungal genera such as Wallemia, Aspergillus, Cladosporium, and Penicillium constitute the key microbes of sunflower plants.

CORRELATION OF BODY MASS INDEX, AGE, IMMUNO-BIOCHEMICAL PARAMETERS OF THE THYROID PANEL WITH INTESTINAL MICROBIOTA IN PATIENTS WITH CARBOHYDRATE METABOLISM DISORDERS AND THYROID DYSFUNCTION

The purpose of the study – to find out the correlations between the intestinal microbiotaand age, anthropometric indicators according to body mass index, immuno- biochemicalindicators of the thyroid panel in patients with carbohydrate metabolism disorders andthyroid dysfunction.Material and methods. The study included 89 patients with carbohydrate metabolismdisorders (type 2 diabetes mellitus, prediabetes, obesity) and thyroid dysfunction(autoimmune thyroiditis, hypothyroidism, Graves’ disease). Anthropometric indicators of height and weight; laboratory determination of immuno- biochemical parametersof carbohydrate metabolism and thyroid hormone were determined. To analyze thecomposition of the intestinal microbiota, fecal samples were taken and the quantitativeand qualitative composition was calculated using the principle of PCR sequencing.Statistical methods of comparison and correlation of variables were used.Results. In patients, several significant correlations were found between the gutmicrobiota and the parameters studied. A negative correlation was found between bodymass index and Bifidobacterium spp. and Escherichia coli and a positive correlationbetween body mass index and some opportunistic pathogens. Thus, with Shigella spp.and Staphylococcus aureus, there is a direct weak reliable relationship, while an inversereliable relationship with Helicobacter pylory. Interesting correlations were foundwith a tendency to confidence with Salmonella spp. and Bacteroides thetaiotaomicrondirect weak and a tendency to a plausible feedback between BMI and Faecalibacteriumprausnitzii and Candida spp. Bacteria of the phylum Firmicutes were inverselycorrelated with fT3 levels. Representatives of the phylum Bacteroidetes found a directcorrelation with fT3, TgAb. Clostridium perfringens was directly correlated with levelsof fT3, fT4, TRAb, TgAb, and Fusobacterium nucleatum was directly correlated withTPOAb. Interestingly, Candida spp. showed an inverse correlation with TPOAb, whileamong this genus of fungi, only Candida krusei was characterized by the appearanceof a correlation as a direct relationship with TRAb. Helicobacter pylory was directlycorrelated with TRAb and TgAb.Conclusions. 1. There are direct and inverse correlations between individualrepresentatives of the intestinal microbiota and body mass index. 2. Establishedcorrelations between individual representatives of the intestinal microbiome and thelevel of thyroid hormones and thyroid antibodies indicate the ability of the microbiometo influence the functional state of the thyroid gland through the mediation of the immunesystem.

The changes of rhizosphere microbial communities in pepper varieties with different capsaicinoids.

Capsaicinoids are produced uniquely in pepper fruits, and its level determines the commercial quality and health-promoting properties of pepper. So, it is particularly important to increase capsaicinoids content in pepper. Rhizosphere microbiota is critical to plant growth and performance, and affected by plant varieties. However, the impact of pepper varieties with different capsaicinoids yields on the rhizosphere microbiota is poorly understood. Using high-throughput sequencing of the 16S rRNA and internal transcribed spacer (ITS) region, we investigated the rhizosphere microbial community among five pepper varieties containing different capsaicinoids. Our results demonstrated that pepper variety significantly influenced the diversity and structure of rhizosphere microbial community. Bacterial diversity in varieties with high capsaicinoids content was significantly higher than in varieties with low capsaicinoids content, while fungal diversity was opposite to bacterial diversity. The correlation analysis revealed that 19 dominant bacterial genera (e.g., Chujaibacter, Rhodanobacter, and Gemmatimonas) were significantly correlated with capsaicinoids content, and nine of them were also significantly associated with soil nutrients, whereas only one fungal genus (Podospora) was significantly correlated with capsaicinoids content. Additionally, almost all genera which significantly correlated to capsaicinoids content were biomarkers of the five pepper varieties and the correlation was well corresponding to the capsaicinoids content. Overall, our results confirmed that the variety of pepper significantly affected the rhizosphere microbial community in the fields, and bacteria and fungi responded differently to capsaicinoids, which may affect the biosynthesis of capsaicinoids and contribute to further improvement of capsaicinoids production in pepper fruits.

Metagenomic and transcriptome insights into the disease resistance mechanisms in fresh-cut apple under pyridoxine treatment

Microbial spoilage poses a significant challenge to fresh-cut apples during storage, impacting quality and consumer health. This study explores pyridoxine’s (vitamin B6; VB6) potential mode of action to mitigate microbial spoilage in fresh-cut apples through physiological, transcriptomic, and metagenomic analysis. VB6 notably reduces microbial spoilage at room temperature by suppressing bacterial genera (Pseudomonas, Curtobacterium, Frigoribacterium) and fungal genera (Alternaria, Penicillium, Aureobasidium, Pseudogymnoascus) proliferation. Spoilage-causing identified biomarkers include species related to Pseudomonas, Curtobacterium, Frigoribacterium, and Penicillium. KEGG analysis suggests correlations of induced disease resistance with tropane alkaloids biosynthesis, plant-pathogen interaction, and phenylpropanoid biosynthesis pathways in fresh-cut apples. Moreover, VB6 treatment enhanced the antioxidant system via maintaining higher total phenolic contents, total flavonoid contents, and ascorbic acid under elevated catalase, superoxide dismutase, and ascorbate peroxidase enzymes activities, induced disease resistance under higher enzymes activities including phenylalanine ammonialyase, chitinase, cinnamate 4-hydroxylase, β-1,3-glucanase, and 4-coumarate: co-enzyme A ligase enzymes activities, maintained elevated VB6 contents, and reduced H2O2 accumulation. Notably, 6 elevated transcription factors involving WRKY, NAC and MYB might regulate disease resistance pathways in fresh-cut apples under VB6 treatment. This research establishes a theoretical and practical foundation for preserving post-processing quality of fresh-cut apples by restraining microbial proliferation through the proposed VB6-induced disease resistance regulatory mechanism.

Evidence to support cultivated fruiting body of Ophiocordyceps sinensis (Ascomycota)'s role in relaxing airway smooth muscle

Ethnopharmacological relevanceOphiocordyceps sinensis (O. sinensis) is a genus of Ascomycete fungus that is endemic to the alpine meadows of the Tibetan Plateau and adjoining Himalayas. It has been used traditionally as a tonic to improve respiratory health in ancient China as well as to promote vitality and longevity. Bioactive components found in O. sinensis such as adenosine, cordycepin, 3-deoxyadenosine, L-arginine and polysaccharides have gained increasing interest in recent years due to their antioxidative and other properties, which include anti-asthmatic, antiviral, immunomodulation and improvement of general health. Aim of the studyThis study's primary aim was to investigate the effect of a cultivated fruiting body of O. sinensis strain (OCS02®) on airways patency and the secondary focus was to investigate its effect on the lifespan of Caenorhabditis elegans. Materials and methodsA cultivated strain, OCS02®, was employed and the metabolic profile of its cold-water extract (CWE) was analysed through liquid chromatography-mass spectrometry (LC-MS). Organ bath approach was used to investigate the pharmacological properties of OCS02® CWE when applied on airway tissues obtained from adult male Sprague-Dawley rats. The airway relaxation mechanisms of OCS02® CWE were explored using pharmacological tools, where the key regulators in airway relaxation and constriction were investigated. For the longevity study, age-synchronised, pos-1 RNAi-treated wild-type type Caenorhabditis elegans at the L4 stage were utilised for a lifespan assay. ResultsVarious glycopeptides and amino acids, particularly a high concentration of L-arginine, were identified from the LC-MS analysis. In airway tissues, OCS02® CWE induced a significantly greater concentration-dependent relaxation when compared to salbutamol. The relaxation response was significantly attenuated in the presence of NG-Nitro-L-arginine methyl ester (L-NAME), 1H-[1,2,4]oxadiazolo [4,3-a]quinoxalin-1-one (ODQ) and several K+ channel blockers. The longevity effect induced by OCS02® CWE (5 mg/mL and above) was observed in C. elegans by at least 17%. ConclusionsThese findings suggest that the airway relaxation mechanisms of OCS02® CWE involved cGMP-dependent and cGMP-independent nitric oxide signalling pathways. This study provides evidence that the cultivated strain of OCS02® exhibits airway relaxation effects which supports the traditional use of its wild O. sinensis in strengthening respiratory health.

Analysis of wheat fungal community succession in traditional storage structures using Illumina MiSeq sequencing technology

The diversity of fungi in wheat with different deoxynivalenol (DON) content at various periods post-harvest and in the environment of storage were investigated. The changes in DON content were measured with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS), and an amplicon sequence analysis of fungi was performed in traditional storage structures using high-throughput sequencing. The changes in temperature, humidity, and CO2 concentration were collected by sensors. In addition, we analyzed principal component analysis, species composition, species differences, and community differences of fungi. There was an obvious separation of the fungal communities under different storage conditions and times. Many fungal genera were gradually decreasing during storage and were eventually undetectable, and many fungal genera that were undetectable at first gradually increased during storage and even became dominant fungal genera. The competition between fungi was fierce. The competition between fungi were affected by the presence of DON. As the initial DON content increased, the contribution of inter-group differences became more obvious. The temperature, humidity, and CO2 concentration of wheat in the silo's environment changed with extended storage time. The content of DON decreased with extended storage time. We had investigated the changes in DON content and their correlation with the changes in fungal communities and environmental factors, which showed a high degree of correlation. This study offers theoretical justification for optimizing safe wheat grain in traditional storage conditions.

The Expanding Mycovirome of Aspergilli.

Mycoviruses are viruses that infect fungi and are widespread across all major fungal taxa, exhibiting great biological diversity. Since their discovery in the 1960s, researchers have observed a myriad of fungal phenotypes altered due to mycoviral infection. In this review, we examine the nuanced world of mycoviruses in the context of the medically and agriculturally important fungal genus, Aspergillus. The advent of RNA sequencing has revealed a previous underestimate of viral prevalence in fungi, in particular linear single-stranded RNA viruses, and here we outline the diverse viral families known to date that contain mycoviruses infecting Aspergillus. Furthermore, we describe these novel mycoviruses, highlighting those with peculiar genome structures, such as a split RNA dependent RNA polymerase gene. Next, we delineate notable mycovirus-mediated phenotypes in Aspergillus, in particular reporting on observations of mycoviruses that affect their fungal host's virulence and explore how this may relate to virus-mediated decreased stress tolerance. Furthermore, mycovirus effects on microbial competition and antifungal resistance are discussed. The factors that influence the manifestation of these phenotypes, such as temperature, fungal life stage, and infection with multiple viruses, among others, are also evaluated. In addition, we attempt to elucidate the molecular mechanisms that underpin these phenotypes, examining how mycoviruses can be targets, triggers, and even suppressors of RNA silencing and how this can affect fungal gene expression and phenotypes. Finally, we highlight the potential therapeutic applications of mycoviruses and how, in an approach analogous to bacteriophage therapy, their ability to produce hypovirulence in Aspergillus might be used to attenuate invasive aspergillosis infections in humans.

Taxonomic reintroduction of the holarctic saprotrophic fungus Crepidotus cinnamomeus

Crepidotus is a genus of common saprotrophic fungi well known especially in the Northern Hemisphere, but distribution patterns of individual species are not sufficiently understood. We redefined a taxonomic circumscription of Crepidotus cinnamomeus based on morphological and molecular congruencies between the type material and recent collections. The species is well delimited from other similar and currently accepted species of the genus. Crepidotus cinnamomeus was found to have a broad holarctic distribution with occurrences in North America, Europe and Asia where it grows on twigs and branches of deciduous trees and shrubs in preferably cold humid habitats. Here we present the first multilocus phylogeny of the genus, including portions of the RPB2 gene. Our study highlights the importance of sufficient sampling from broader areas supported by sequence data, which is essential for estimation of species delimitation, distribution and correct name assignment for Crepidotus species.

Contribution of gut microbiota to biodegradation of polystyrene in Tenebrio molitor larvae: Microbiome under antibiotic suppression of Gram-positive, Gram-negative, and fungal microbes

The discovery of plastic biodegradation by insects such as Tenebrio molitor larvae has been well known, however, understanding of the roles of larval gut microorganisms is still very limited. The contribution of the gut microbes belonging to respective Gram-positive (G+), Gram-negative (G−), and fungal (F) groups remains unclear. In this study, we tested polystyrene (PS) biodegradation by T. molitor larvae under three selective antibiotics i.e., gentamicin sulfate (GMS) against G− bacteria, ampicillin (AMP) against G+ bacteria and nystatin (NS) against fungi. The larvae consumed and biodegraded PS foams with Mn 86.381 kDa and Mw 181.176 kDa under antibiotic suppressions at reduced rates versus control (CK) with a sequence of CK>GMS>AMP>NS group. Specifically, only NS group showed a significant decreased in consumption compared to the control. The gut microbial counts decreased with GMS, AMP, or NS addition during the PS feeding. The respective gut microbial counts decreased by 103 to 104 with GMS, AMP, or NS addition PS feeding. Analyses of DSC, TGA, FTIR confirmed oxidation and biodegradation in the presence of antibiotics. The ingested PS polymers were depolymerized and mass reduction with negative influence in the order of NS<AMP<GMS. The negative impact of antibiotic suppression on PS biodegradation process was as follows: anti-fungi reagent > anti-G+ bacteria > anti- G− bacteria. Changes in chemical functional groups are probably related to certain gut microbes, such as the fungal genus of Candida, and bacterial genera of unclassified Enterobacteriaceae and Lactobacillus. Our findings provided new insights into the mechanisms of the biodegradation of plastics in insects.