Pathogenic Fungal Species Research Articles

Functional Analysis of Durum Wheat GASA1 Protein as a Biotechnological Alternative Against Plant Fungal Pathogens and a Positive Regulator of Biotic Stress Defense.

Plants are frequently challenged by a variety of microorganisms. To protect themselves against harmful invaders, they have evolved highly effective defense mechanisms, including the synthesis of numerous types of antimicrobial peptides (AMPs). Snakins are such compounds, encoded by the GASA (Gibberellic Acid-Stimulated Arabidopsis) gene family, and are involved in the response to biotic and abiotic stress. Here, we examined the function of the newly identified TdGASA1 gene and its encoded protein in Triticum durum subjected to different biotic stress-related simulants, such as mechanical injury, methyl jasmonate (MeJA), indole-3-acetic acid (IAA), salicylic acid (SA), hydrogen peroxide (H2O2), as well as infection with pathogenic fungi Fusarium graminearum and Aspergillus niger. We found that in durum wheat, TdGASA1 transcripts were markedly increased in response to these stress simulants. Isolated and purified TdGASA1 protein exhibited significant antifungal activity in the growth inhibition test conducted on eight species of pathogenic fungi on solid and liquid media. Transgenic Arabidopsis lines overexpressing TdGASA1 obtained in this study showed higher tolerance to detrimental effects of H2O2, MeJA, and ABA treatment. In addition, these lines exhibited resistance to Fusarium graminearum and Aspergillus niger, which was linked to a marked increase in antioxidant activity in the leaves under stress conditions. This resistance was correlated with the upregulation of pathogenesis-related genes (AtPDF1.2a, AtERF1, AtVSP2, AtMYC2, AtPR1, AtACS6, AtETR1, and AtLOX2) in the transgenic lines. Overall, our results indicate that TdGASA1 gene and its encoded protein respond ubiquitously to a range of biotic stimuli and seem to be crucial for the basal resistance of plants against pathogenic fungi. This gene could therefore be a valuable target for genetic engineering to enhance wheat resistance to biotic stress.

A Draft Genome Resource for a Cacao Thread Blight Disease–Causing Strain of Paramarasmius palmivorus

Thread blight disease (TBD) is an emerging foliar disease on cacao ( Theobroma cacao), the source of chocolate. Multiple species of pathogenic fungi in the Marasmiinae suborder of Agaricales are responsible for causing TBD in cacao. A recent phylogenetic study showed that Marasmius palmivorus, the second most frequently isolated TBD-causing fungus in Ghana, was phylogenetically distinct from the Marasmiaceae genera Marasmius and Moniliophthora, leading to the naming of a new genus, Paramarasmius. The genus currently contains two species, the type species P. palmivorus and P. mesosporus. This report describes our release of a draft nuclear genome assembly and annotation of P. palmivorus strain GH-12 derived from long- and short-read sequencing. This high-quality draft is the first released genome for P. palmivorus and provides insight into the pathogenicity and evolution of an emerging pathogen. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

In Vitro evaluation of some fungicidal bioactive chemicals against fusarium spore germination and survival

The genus Fusarium are the most important pathogens associated with different plants including crop plants, fruits, vegetables, etc. causing of constrained production and productivity crops. Bioactive compounds are environmentally friendly and amenable. This study aimed to evaluate the effectiveness of some bio-active compounds derived from Bacillus strain for the in vitro control of Fusarium mold. Seven (7) isolates of the Fusarium complex were isolated from various stored fruits, vegetables and food grains using Potato Dextrose Agar (PDA) media supplemented with antibacterial agent. The growth and survival of the respective spores were challenged with supernatants of overnight-grown culture of Bacillus subtilis TC17 for 20 minutes. The supernatant prevented the germination of spores of some fungi strains in the order; F. solani, F. oxysporum, F. equiseti, F. acuminatum, F. proliferatum, F. moniliforme and F. tricinctum against control. Therefore, this research showed that the bio-active agent can be used to control the pervasive plant pathogenic fungal species with outstanding result and therefore should be developed further for registration for commercial applications.

Yeast-contaminated water as a potential emerging health concern: a review

Invasive fungal infections pose a serious risk to human health; therefore, it is important to study the dissemination and proliferation of pathogenic fungal species in the environment. This could prove useful in preventing infections in susceptible individuals, such as those who are immune-compromised or suppressed. Pathogenic yeasts belonging to the genera Candida, Cryptococcus and Rhodotorula are commonly found in various water sources that are used for daily activities and are included in the World Health Organization fungal priority pathogens list, further warranting investigation into the possibility that infections may occur through contact with yeast-contaminated water. In addition, the close association between antifungal pollutants and yeast in water may induce acquired antifungal resistance development, further complicating the effective treatment of these infections. Thus, investigating the presence and antifungal susceptibility of yeast found in water and identifying ways to monitor potential fungal pathogens may prove useful in combating invasive fungal infections. This review deals with the occurrence and infection risks posed by pathogenic yeasts in water as well as the possibility of these yeasts acquiring antifungal resistance due to the simultaneous presence of antifungal compounds from medical and agricultural runoff.

Phytochemical profiling and biological evaluation of the residues from industrial hemp (Cannabis sativa L.) inflorescences trimming: Focus on water extract

The study focused on investigating the phytochemical composition and bio-pharmacological properties of a water extract obtained from industrial hemp by-products, after trimming female inflorescences of Cannabis sativa L., cultivar Kompolti. The extract was found to be rich in phenolic compounds, particularly gallic acid, catechin, coumaric acid, ferulic acid, and benzoic acid. It also contained significant amounts of cannabidiolic acid and cannabigerolic acid as the main terpenophenols. To assess the biological potential of the extract, various ecotoxicological assays were conducted. The extract did not show significant phytotoxic effects on seedling germination in the allelopathic assay. In the brine shrimp (Artemia salina) lethality test, the LC50 value was 1.726 mg/mL, and in the Daphnia magna test, the extract showed no cardiotoxicity effects at the same concentration; thus, confirming its biocompatibility with these eukaryotic organisms. Additionally, the extract did not induce cytotoxicity in the murine C2C12 cell line till to the concentration of 1000 μg/mL. In isolated mouse prostate specimens, the extract (10–1000 μg/mL) also prevented LPS-induced gene expression of pro-inflammatory cytokines, namely tumor necrosis factor (TNF)α, interleukin (IL)-6, and IL-1β. Furthermore, the extract exhibited inhibitory effects on the growth of pathogenic bacterial, fungal, and dermatophyte species commonly associated with prostatitis. These results suggest that the residual powder from female inflorescence trimming can be considered an innovative plant material from the industrial hemp supply chain that deserves to be valorised in terms of recycling and upcycling; thus, reducing the environmental impact of the by-products and also opening the way for innovative health-promoting agents.

Diagnosis of fungal diseases in quinoa (Chenopodium quinoa Willd) in Burkina Faso

Quinoa is an Andean pseudo-cereal crop that is mainly cultivated for its energy and protein-rich, gluten-free seeds. Quinoa is currently being popularized in Burkina Faso, but manifestations of fungal diseases have been observed on the plants. The aim of this study was to establish a causal relationship between the observed symptoms and the associated fungal pathogens. Samples of symptomatic organs were collected from the three agro-ecological zones and examined for fungal pathogen species via isolation on media. A total of six (6) diseases and twenty-nine (29) fungal species were described and identified in the collected organs. The diseases were present in the following proportions: (i) panicle browning followed by complete plant drying (45.36%), (ii) brown crown rot (41.20%), (iii) brown stalk rot (27.31%), (iv) damping-off (22.68%), (v) chlorosis with necrotic brown leaf spots (19.33%), and (vi) plant wilting (13.88%). The essential epidemiological factors of these pathologies are discussed.

Germplasm Resource Mining of Fen-Flavor Baijiu Brewing Micro-Organisms and Screening of Important Functional Strains

The exploration of microbial genetic resources for the production of fFen-flavor Baijiu has not only enriched the microbial library for baijiu production but has also laid the foundation for process improvement and strain optimization in baijiu brewing. In this study, a total of 177 fungal isolates were screened, including Saccharomyces cerevisiae, non-Saccharomyces cerevisiae, molds, and some pathogenic bacteria. Among them, Saccharomyces cerevisiae was the most abundant with 119 isolates, playing a major role in the fermentation of baijiu production. A total of 148 bacterial isolates were obtained from the fermentation mash samples, showing greater diversity compared to fungi. Bacillus species were the most abundant, with 94 isolates. Bacillus licheniformis, in particular, can produce a rich enzymatic system and flavor precursors, making it an important contributor to the sensory quality of baijiu. Lactic acid bacteria were the second most abundant, with 16 isolates. Additionally, five pathogenic fungal species were identified, including Candida pelliculosa, Candida lusitaniae, Fusarium oxysporum, Fusarium solani and Talaromyces marneffei. Six pathogenic bacterial species were also isolated, namely Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus xylosus, Moraxella osloensis, Actinomyces meyeri and Stenotrophomonas maltophilia. Finally, two strains of high acetate ethyl ester-producing yeast and lactate-degrading bacteria with good tolerance to temperature, pH, and ethanol concentration were identified as Saccharomyces cerevisiae and Bacillus licheniformis, respectively.

Malassezia responds to environmental pH signals through the conserved Rim/Pal pathway.

During mammalian colonization and infection, microorganisms must be able to rapidly sense and adapt to changing environmental conditions including alterations in extracellular pH. The fungus-specific Rim/Pal signaling pathway is one process that supports microbial adaptation to alkaline pH. This cascading series of interacting proteins terminates in the proteolytic activation of the highly conserved Rim101/PacC protein, a transcription factor that mediates microbial responses that favor survival in neutral/alkaline pH growth conditions, including many mammalian tissues. We identified the putative Rim pathway proteins Rim101 and Rra1 in the human skin colonizing fungus Malassezia sympodialis. Gene deletion by transconjugation and homologous recombination revealed that Rim101 and Rra1 are required for M. sympodialis growth at higher pH. In addition, comparative transcriptional analysis of the mutant strains compared to wild-type suggested mechanisms for fungal adaptation to alkaline conditions. These pH-sensing signaling proteins are required for optimal growth in a murine model of atopic dermatitis, a pathological condition associated with increased skin pH. Together, these data elucidate both conserved and phylum-specific features of microbial adaptation to extracellular stresses.IMPORTANCEThe ability to adapt to host pH has been previously associated with microbial virulence in several pathogenic fungal species. Here we demonstrate that a fungal-specific alkaline response pathway is conserved in the human skin commensal fungus Malassezia sympodialis (Ms). This pathway is characterized by the pH-dependent activation of the Rim101/PacC transcription factor that controls cell surface adaptations to changing environmental conditions. By disrupting genes encoding two predicted components of this pathway, we demonstrated that the Rim/Pal pathway is conserved in this fungal species as a facilitator of alkaline pH growth. Moreover, targeted gene mutation and comparative transcriptional analysis support the role of the Ms Rra1 protein as a cell surface pH sensor conserved within the basidiomycete fungi, a group including plant and human pathogens. Using an animal model of atopic dermatitis, we demonstrate the importance of Ms Rim/Pal signaling in this common inflammatory condition characterized by increased skin pH.

Development of PCR-Multiplex Assays for Identification of the Herpotrichiellaceae Family and Agents Causing Chromoblastomycosis.

The Herpotrichiellaceae family is an important group of dematiaceous filamentous fungi, associated with a variety of pathogenic fungal species causing chromoblastomycosis (CBM) and phaeohyphomycosis (PHM), both with polymorphic clinical manifestations and worldwide incidence. Currently, the identification of this family and determination of the causative agent is challenging due to the subjectivity of morphological identification methods, necessitating the use of molecular techniques to complement diagnosis. In this context, genetic sequencing of the Internal Transcribed Spacer (ITS) has become the norm due to a lack of alternative molecular tools for identifying these agents. Therefore, this study aimed to develop PCR-Multiplex methodologies to address this gap. Sequences from the ITS and Large Subunit (LSU) of ribosomal DNA were used, and after manual curation and in vitro analyses, primers were synthesized for the identification of the targets. The primers were optimized and validated in vitro, resulting in two PCR-Multiplex methodologies: one for identifying the Herpotrichiellaceae family and the bantiana clade, and another for determining the species Fonsecaea pedrosoi and Fonsecaea monophora. Ultimately, the assays developed in this study aim to complement other identification approaches for these agents, reducing the need for sequencing, improving the management of these infections, and enhancing the accuracy of epidemiological information.

Malassezia responds to environmental pH signals through the conserved Rim/Pal pathway.

During mammalian colonization and infection, microorganisms must be able to rapidly sense and adapt to changing environmental conditions including alterations in extracellular pH. The fungus-specific Rim/Pal signaling pathway is one process that supports microbial adaptation to alkaline pH. This cascading series of interacting proteins terminates in the proteolytic activation of the highly conserved Rim101/PacC protein, a transcription factor that mediates microbial responses that favor survival in neutral/alkaline pH growth conditions, including many mammalian tissues. We identified the putative Rim pathway proteins Rim101 and Rra1 in the human skin colonizing fungus Malassezia sympodialis. Gene deletion by transconjugation and homologous recombination revealed that Rim101 and Rra1 are required for M. sympodialis growth at higher pH. Additionally, comparative transcriptional analysis of the mutant strains compared to wild-type suggested mechanisms for fungal adaptation to alkaline conditions. These pH-sensing signaling proteins are required for optimal growth in a murine model of atopic dermatitis, a pathological condition associated with increased skin pH. Together these data elucidate both conserved and phylum-specific features of microbial adaptation to extracellular stresses.

Sclerotinia rot of Zephyranthes candida caused by Sclerotinia sclerotiorum and Sclerotinia minor.

Sclerotinia rot is a serious disease that occurs on Zephyranthes candida. A thorough understanding of the pathogenic fungal species and understanding the biological characteristics are important for controlling sclerotinia. Fungal strains were isolated from the diseased leaves of Z. candida through tissue isolation. Koch's hypothesis screened pathogenic strains by pathogenicity of healthy leaves, including re-isolation and identification. A multigene phylogenetic tree was constructed by extracting genomic DNA from pathogenic strains and measuring the nucleotide sequences at four sites, including the internal transcribed spacer (ITS), RNA polymerase II second largest subunit (RPB2), glyceraldehyde-3-phosphate dehydrogenase (G3PDH), and heat shock protein 60 (HSP60). Morphological characteristics of the fungal structures were evaluated through microscopic analysis. The growth of pathogens was observed and recorded under different pH, different temperatures, different carbon sources and different nitrogen sources to clarify their biological characteristics. Representative strains D7, D13, X4, and X15 infected Z. candida and caused sclerotinia rot. At the beginning of the culture, white flocculent fungal hyphae appeared on the potato dextrose agar (PDA) medium, and black spherical to irregular-shaped sclerotia appeared at the edge of the colony after 7 days. The diameter of the sclerotia was 2.4-8.6 mm and 0.4-0.9 mm, respectively. One sclerotium was able to germinate from 1 to 5 apothecia. Ascus were cylindrical or spindle-shaped, with a size of 110.0-120.0 × 9.2-11.6 μm. One ascus contained eight colorless, oval ascospores, with a size of 8.4-12.0 × 4.5-5.5 μm. Based on the phylogenetic tree constructed with the gene sequences for ITS, G3PDH, HSP60, and RPB2, D7 and D13 shared 99% homology with sclerotinia sclerotiorum, whereas X4 and X15 shared 99% homology with sclerotinia minor. S. sclerotiorum growth was more suitable when the culture temperature was 15°C-25°C, pH 5.0, carbon source was maltose and nitrogen source was yeast powder. S. minor growth was more suitable when the culture temperature was 15°C, pH 5.0, the carbon source was glucose, and the nitrogen source was yeast powder. The results identified the pathogens as S. sclerotiorum and S. minor. To the best of our knowledge, this is the first report of S. sclerotiorum and S. minor causing sclerotinia rot on Z. candida. We herein aimed to identify the causal agent of sclerotinia rot of Z. candida in China based on morphological characteristics, molecular identification, and pathogenicity tests. Performed the experiments on the biological characteristics, to understand the law of disease occurrence. We also evaluated methods for the effective control of this disease. Our findings provide support for further studies on the pathogenesis mechanism of sclerotinia rot.

Phenotypic characterization of HAM1, a novel mating regulator of the fungal pathogen Cryptococcus neoformans.

Fungal mating is a vital part of the lifecycle of the pathogenic yeast Cryptococcus neoformans. More than just ensuring the propagation of the species, mating allows for sexual reproduction to occur and generates genetic diversity as well as infectious propagules that can invade mammalian hosts. Despite its importance in the biology of this pathogen, we still do not know all of the major players regulating the mating process and if they are involved or impact its pathogenesis. Here, we identified a novel negative regulator of mating that also affects certain cellular characteristics known to be important for virulence. This gene, which we call HAM1, is widely conserved across the cryptococcal family as well as in many pathogenic fungal species. This study will open new avenues of exploration regarding the function of uncharacterized but conserved genes in a variety of pathogenic fungal species and specifically in serotype A of C. neoformans.

Characterization and biocontrol potential of some rhizobacteria against fungal pathogens causing foliar diseases in maize

Maize is one of the most consumed cereal crops worldwide, and it is a strategic crop to the attainment of SDG 2 of Zero hunger. Despite its importance, the cultivation of maize has been significantly impaired by fungal pathogens causing foliar diseases. The occurrence of this disease in maize plantations at the Research Farm of the North-West University, Molelwane, Mafikeng, South Africa prompted this investigation. Samples of diseased maize rhizosphere soil were aseptically collected. Bacteria species associated with the rhizosphere were isolated and characterized as Bacillus siamensis, Enterobacter asburiae, Enterobacter chengduensis, Priestia aryabhattai, Burkholderia sp., Priestia megaterium strain AOA6 and Priestia megaterium strain AOA7. The anti-fungicidal potentials of the bacterial species were evaluated against pathogenic fungal species, Nigrospora sphaerica, Alternaria alternata and Fusarium equiseti in-vitro. The percentage mycelia growths were calculated and the data were subjected to ANOVA using SAS version 9.8. All the seven bacteria isolates tested positive to ammonia production, phosphate solubilization, siderophore production and ACC deaminase tests. The percentage mycelia inhibition showed Nigrospora sphaerica (36.29%), A. alternata (26.19%) and F. equiseti (20.63%) as the order of fungal inhibition by the bacteria species. Furthermore, E. asburiae > P. megatarium strain AOA7 > B. siamensis > P. aryabhattai > E. chengduensis > Bulkholderia sp. were the order of antifungal efficacy of the bacteria species evaluated. In conclusion, the efficacy of the bacteria especially E. asburiae, P. megatarium strain AOA7 and B. siamensis over various fungal pathogens. The result obtained, therefore, justifies the further investigation, formulation and deployment of the bacteria species as biofungicide in the management of foliar diseases of maize. Keywords: antifungicidal potential, biofungicide, microbial formulations, rhizosphere, zero hunger.

Determination of in vitro antifungal activity of dihydroisoxazole dimethanol compound against dermatophytes obtained from clinical isolates and design of some new dihydroisoxazole dimethanol compounds

In this study, the in vitro antifungal activity of (3-(4-chlorophenyl)-4,5-dihydroisoxazole-4,5-diyl) dimethanol compound (1) was investigated against two pathogenic fungi species (Trichophyton mentagrophytes and Microsporum canis) and important results were obtained. The difficulty of treating fungal diseases induced us to assess the antifungal properties of dihydroisoxazole dimethanol compound. The broth microdilution method was used to determine the minimum inhibitory concentration (MIC). The compound (1) showed an antifungal effect with MIC=12.5 µg ml-1 on M. canis and MIC=50 µg ml-1 on T. mentagrophytes, respectively. To prepare potentially more effective antifungal agents, new dihydroisoxazole derivatives (2-32) were theoretically designed. The geometrical optimization of all compounds (1-32) was performed using the semi-empirical AM-1 level. Some structural parameters of the optimized compounds (1-32) were also calculated.

Preliminary Evidence for the Role of Fungi, Specifically Chaetomium, in Gulf War Illness.

For veterans of the Persian Gulf War (1990-1991), dozens of possible causes for their illness have been proposed. We hypothesize that all may be correct. These may have weakened the immunity of the military personnel to fungal pathogens in the soil. These microbes, in turn, may have afflicted the veterans either directly by infection or indirectly by toxins. In 1990, the military (source confidential) provided the first author with soil samples from the Persian Gulf to determine if there were biothreats present. His team found that per gram of soil, there had few bacteria but many fungi. The National Centre for Human Mycotic Diseases (Edmonton) identified some of these fungi. They sent to the first author reference cultures of 12 pathogenic fungal species isolated from Canadian patients. Supernatant antigens of these fungi were used to assess if control and Gulf War Illness (GWI) patient sera had IgG antibodies against them. Human sera were tested on pathogenic fungal supernatant antigens. Controls had low IgG titers against all 12 fungal sources. Gulf War Illness (GWI) patient sera had low IgG titers against 11 of the 12 fungal antigens. However, 12 of 28 GWI patient sera (43%, P ≤ .0002 compared to controls) had high IgG titers against one fungus, Chaetomium, supernatant antigen. We suggest that the military personnel in the Persian Gulf War (1990-1991) may have had their immunity weakened from a variety of causes. The role of pathogenic fungi and/or their supernatant antigens or toxins as a contributing factor to GWI should be further investigated.

Phytomonitoring of medicinal plants: pests and diseases in the VILAR botanical garden

Medicinal plants represent a separate group of plants that requires an environmentally safety approach to their protection from harmful organisms. The biotic factor significantly affects on the productivity of medicinal plants and the quality of medicinal raw materials obtained from them.The VILAR Botanical Garden is a unique scientific and crop production site, its main task is the conservation of rare species of medicinal plants, as well as the development agrotechnologies for species recently taken from nature, or another regions and countries. However, when we growing plants in biocollections on one place for a number of years, there is quite favorable conditions for the reproduction of pests and the spread of diseases. The monitoring results make it possible to monitor and predict the condition of crops on experimental plots and in biocollections. At the same time, a purposeful systematic study of plant pests and diseases in the VILAR Botanical Garden has not been carried out in recent years. Our studies was conducted in 2022–2023 years on 63 species of medicinal plants and allowed to clarify the species composition of pests, including 26 species of phytophages and 9 species of pathogenic fungi. The phytosanitary condition of the regions of the Botanical Garden and the crops on the experimental field was satisfactory, there was no loss of species or crops from the collection due to severe disease or pest damage. Representatives of the family of leaf beetles (Chrysomelidae) and true aphids (Aphididae) had the greatest prevalence among pests, among the diseases — powdery and rusty.

Design, Synthesis, DFT, docking Studies, and antimicrobial evaluation of novel benzimidazole containing sulphonamide derivatives

In silico approaches have been employed to design a new series of benzimidazole-containing sulphonamide derivatives and qualified compounds have been synthesized to analyze their potential as antimicrobial agents. Antibacterial screening of all synthesized compounds was done using the broth microdilution method against several human pathogenic bacteria, viz. Gram-positive bacteria [B. cerus (NCIN-2156), B. subtilis (ATCC-6051), S. aureus (NCIM-2079)] and Gram-negative bacteria [P. aeruginosa (NCIM-2036), E. coli (NCIM-2065), and a drug-resistant strain of E. coli (U-621)], and the compounds presented admirable MIC values, ranging between 100–1.56 µg/mL. The combinatorial analysis showed the magnificent inhibitory efficiency of the tested compounds, acquired equipotent to ten-fold more potency compared to original MIC values. An immense synergistic effect was exhibited by the compounds during combination studies with reference drugs chloramphenicol and sulfamethoxazole was presented as fractional inhibitory concentration (∑FIC). Enzyme inhibition studies of all synthesized compounds were done by using peptidyl transferase and dihydropteroate synthase enzymes isolated from E. coli and S. aureus and each of the compound presented the admirable IC50 values, where the lead compound 3 bound to peptidyl transferase (of S. aureus with IC50 363.51 ± 2.54 µM and E. coli IC50 1.04 ± 0.08 µM) & dihydropteroate synthase (of S. aureus IC50 3.51 ± 0.82 µM and E. coli IC50 2.77 ± 0.65 µM), might account for the antimicrobial effect, exhibited excellent inhibition potential. Antifungal screening was also performed employing food poisoning methods against several pathogenic fungal species, viz A. flavus, F. oxysporum, A. niger, and A. brassicae. The obtained result indicated that few compounds can prove to be a potent drug regimen against dreaded MDR strains of microbes. Structural activity relationship (SAR) analysis and docking studies reveal that the presence of electron-withdrawing, polar, and more lipophilic substituents positively favor the antibacterial activity, whereas, electron-withdrawing, more polar, and hydrophilic substituents favor the antifungal activities. A robust coherence has been found in in-silico and in-vitro biological screening results of the compounds.

Fungal profile of eggshells from commercial and free-range hens of a supermarket chain in Fortaleza, CE, Brazil

Eggs are perishable and fragile foods because of their easy contamination by different microorganisms, such as fungi. Hence, research on egg safety and quality has been recently developed worldwide to minimize illness transmitted by this food, although most present mainly pathogenic bacteria. Thus, this study identified potentially pathogenic fungal species in eggshells from free-range and commercial hens offered in supermarkets in Fortaleza, CE, Brazil. The research was performed at the Vettings laboratory at the State University of Ceará (UECE) with 40 eggs: 20 from commercial and 20 from free-range hens. The eggshells were assessed using the dextrose evaluation method for pathogenic cultivation, commensal, and yeast fungi. Subsequently, readings were taken to identify and count the fungi on a binocular light microscope in 100x increments. Both egg categories showed a significant number of colony-forming units (CFU). The study identified eight different fungal species in both egg production types. The most prevalent fungal colonies in the free-range hen lineage (brown shell) were yeast spp. and Penicillium citrinum, and the laying hen lineage (white shell) had mostly Penicillium spp. and yeast spp. Therefore, both egg production systems showed similar fungal contamination, which suggests that the manipulation and/or storage are adequate despite the lack of strict food safety regulations or supervision for eggs in Brazil.

Host–pathogen interaction between the African fig fly, Zaprionus indianus, and its external mycobiome under laboratory conditions

AbstractThe African fig fly, Zaprionus indianus Gupta (Diptera: Drosophilidae), is an ecologically diverse pest species that interacts with and feeds on various microbial pathogens including bacteria and yeast found in decomposing fruits. However, the interaction of Z. indianus with its microbial community and microbial pathogens is obscure. To determine the presence of fungal pathogens, we collected wild Z. indianus from the northwestern part of the Indian subcontinent. Based on molecular identification and phylogenetic analysis, Debaryomyces hansenii (Zopf) Lodder & Kreger‐van Rij (isolate ziha1) was the most commonly observed fungus associated with Z. indianus. Furthermore, we identified two more opportunistic fungal pathogens: Aspergillus flavus Link (isolate zias2), and Pichia kudriavzevii Boidin, Pignal & Besson (isolate zibd3). The interaction of isolated fungi with Z. indianus was evaluated in terms of larval mortality, adult emergence, and fecundity. Debaryomyces hansenii ziha1 resulted in 90% emergence rate for adults, and did not cause significant mortality in the larval stage. In contrast, A. flavus zias2 and P. kudriavzevii zibd3 showed a significant reduction in fecundity and caused 99% and 74% larval mortality of Z. indianus, respectively. In the laboratory oviposition preference assay, mated females of Z. indianus preferred D. hansenii ziha1 supplemented food with a positive oviposition index compared to the uninfected control and compared to food infected with P. kudriavzevii zibd3 or A. flavus zias2. These findings underscore Z. indianus' potential to act as a reservoir for both symbiotic and pathogenic fungal species, some of which may be further harnessed for effective fruit fly pest control strategies.

Re-discovery of MS-347a as a fungicide candidate through a new drug discovery platform with a multidrug-sensitive Saccharomyces cerevisiae screening system and the introduction of a global secondary metabolism regulator, laeA gene.

We found that the culture broth of fungi showed anti-fungal activity against multidrug-sensitive budding yeast. However, we could not identify the anti-fungal compound due to the small quantity. Therefore, we attempted to increase the productivity of the target compound by the introduction of a global secondary metabolism regulator, laeA to the strain, which led to the successful isolation of 10-folds greater amount of MS-347a (1) than Aspergillus sp. FKI-5362. Compound 1 was not effective against Candida albicans and the detailed anti-fungal activity of 1 remains unverified. After our anti-fungal activity screening, 1 was found to inhibit the growth of broad plant pathogenic fungal species belonging to the Ascomycota. It is noteworthy that 1 showed little insecticidal activity against silkworms, suggesting its selective biological activity against plant pathogenic fungi. Our study implies that the combination strategy of multidrug-sensitive yeast and the introduction of laeA is useful for new anti-fungal drug discovery.