RESUMO
Soil and wastewater samples contaminated by petroleum-related industries were collected from various locations in Saudi Arabia, a country known for its vast oil reserves. The samples were analyzed for their physicochemical properties, including the presence of metals, petroleum hydrocarbons, and aromatic compounds. A total of 264 fungal isolates were analyzed and categorized into eight groups of Aspergillus (194 isolates) and four groups of Penicillium (70 isolates). The potential of these fungal groups to grow in oil or its derivatives was investigated. Two isolates, Aspergillus tubingensis FA-KSU5 and A. niger FU-KSU69, were utilized in two remediation experiments-one targeting wastewater and the other focusing on polluted soil. The FA-KSU5 strain demonstrated complete removal of Fe3+, As3+, Cr6+, Zn2+, Mn2+, Cu2+ and Cd2+, with bioremediation efficiency for petroleum hydrocarbons in the wastewater from these sites ranging between 90.80 and 98.58%. Additionally, the FU-KSU69 strain achieved up to 100% reduction of Co2+, Ba2+, B3+, V+, Ni2+, Pb2+ and Hg2+, with removal efficiency ranging from 93.17 to 96.02% for aromatic hydrocarbons after 180 min of wastewater treatment. After 21 days of soil incubation with Aspergillus tubingensis FA-KSU5, there was a 93.15% to 98.48% reduction in total petroleum hydrocarbons (TPHs) and an 88.11% to 97.31% decrease in polycyclic aromatic hydrocarbons (PAHs). This strain exhibited the highest removal rates for Cd2+ and As3+ followed by Fe3+, Zn2+, Cr6+, Se4+ and Cu2+. Aspergillus niger FU-KSU69 achieved a 90.37% to 94.90% reduction in TPHs and a 95.13% to 98.15% decrease in PAHs, with significant removal of Ni2+, Pb2+ and Hg2+, followed by Co2+, V+, Ba2+ and B3+. The enzymatic activity in the treated soils increased by 1.54- to 3.57-fold compared to the polluted soil. Although the mixture of wastewater and polluted soil exhibited high cytotoxicity against normal human cell lines, following mycoremediation, all treated soils and effluents with the dead fungal biomass showed no toxicity against normal human cell lines at concentrations up to 500 µL/mL, with IC50 values ≥ 1000 µL/mL. SEM and IR analysis revealed morphological and biochemical alterations in the biomass of A. tubingensis FA-KSU5 and A. niger FA-KSU69 when exposed to petroleum effluents. This study successfully introduces non-toxigenic and environmentally friendly fungal strains play a crucial role in the bioremediation of contaminated environments. Both strains serve as low-cost and effective adsorbents for bio-remediating petroleum wastewater and oil-contaminated soil. Heavy metals and hydrocarbons, the primary pollutants, were either completely removed or reduced to permissible levels according to international guidelines using the dead biomass of FA-KSU5 and FA-KSU69 fungi. Consequently, the environments associated with this globally significant industry are rendered biologically safe, particularly for humans, as evidenced by the absence of cytotoxicity in samples treated with A. tubingensis FA-KSU5 and A. niger FA-KSU69 on various human cell types.
Assuntos
Aspergillus , Biodegradação Ambiental , Petróleo , Microbiologia do Solo , Poluentes do Solo , Águas Residuárias , Águas Residuárias/microbiologia , Águas Residuárias/química , Petróleo/metabolismo , Poluentes do Solo/metabolismo , Aspergillus/metabolismo , Aspergillus/isolamento & purificação , Aspergillus/crescimento & desenvolvimento , Aspergillus/classificação , Penicillium/metabolismo , Penicillium/isolamento & purificação , Arábia Saudita , Poluição por Petróleo , Fungos/metabolismo , Fungos/classificação , Fungos/isolamento & purificação , Metais/metabolismo , Solo/química , Hidrocarbonetos/metabolismoRESUMO
Fungal pathogens exhibit extensive strain heterogeneity, including variation in virulence. Whether closely related non-pathogenic species also exhibit strain heterogeneity remains unknown. Here, we comprehensively characterized the pathogenic potentials (i.e., the ability to cause morbidity and mortality) of 16 diverse strains of Aspergillus fischeri, a non-pathogenic close relative of the major pathogen Aspergillus fumigatus. In vitro immune response assays and in vivo virulence assays using a mouse model of pulmonary aspergillosis showed that A. fischeri strains varied widely in their pathogenic potential. Furthermore, pangenome analyses suggest that A. fischeri genomic and phenotypic diversity is even greater. Genomic, transcriptomic, and metabolic profiling identified several pathways and secondary metabolites associated with variation in virulence. Notably, strain virulence was associated with the simultaneous presence of the secondary metabolites hexadehydroastechrome and gliotoxin. We submit that examining the pathogenic potentials of non-pathogenic close relatives is key for understanding the origins of fungal pathogenicity.
Assuntos
Aspergillus , Animais , Virulência , Aspergillus/patogenicidade , Aspergillus/genética , Aspergillus/metabolismo , Camundongos , Gliotoxina/metabolismo , Modelos Animais de Doenças , Aspergilose Pulmonar/microbiologia , Feminino , Genoma FúngicoRESUMO
Inflammation serves as an intricate defense mechanism for tissue repair. However, overactivation of TLR4-mediated inflammation by lipopolysaccharide (LPS) can lead to detrimental outcomes such as sepsis, acute lung injury, and chronic inflammation, often associated with cancer and autoimmune diseases. This study delves into the anti-inflammatory properties of "Aspergillus unguis isolate SP51-EGY" on LPS-stimulated RAW 264.7 macrophages. Through real-time qPCR, we assessed the expression levels of pivotal inflammatory genes, including iNOS, COX-2, TNF-α, and IL-6. Remarkably, our fungal extracts significantly diminished NO production and showed noteworthy reductions in the mRNA expression levels of the aforementioned genes. Furthermore, while Nrf2 is typically associated with modulating inflammatory responses, our findings indicate that the anti-inflammatory effects of our extracts are not Nrf2-dependent. Moreover, the chemical diversity of the potent extract (B Sh F) was elucidated using Q-TOF LC-HRMS, identifying 54 compounds, some of which played vital roles in suppressing inflammation. Most notably, compounds like granisetron, fenofibrate, and umbelliprenin were found to downregulate TNF-α, IL-1ß, and IL-6 through the NF-κB signaling pathway. In conclusion, "Aspergillus unguis isolate SP51-EGY", isolated from the Red Sea, Egypt, has been unveiled as a promising TLR4 inhibitor with significant anti-inflammatory potentials, presenting novel insights for their potential therapeutic use in inflammation.
Assuntos
Anti-Inflamatórios , Aspergillus , Receptor 4 Toll-Like , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Camundongos , Animais , Anti-Inflamatórios/farmacologia , Células RAW 264.7 , Aspergillus/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/microbiologia , Cromatografia Líquida/métodos , Inflamação/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico/metabolismo , Espectrometria de Massas , Interleucina-6/metabolismo , Interleucina-6/genéticaRESUMO
This study focused on the bioactive secondary metabolites of an endophytic fungus Aspergillus sp. CCH-1E from Catharanthus roseus. The secondary metabolites from Aspergillus sp. CCH-1E were isolated by using various chromatographic methods [such as normal-phase and reversed-phase chromatography and high-performance liquid chromatography(HPLC)], and their structures were identified by various spectroscopic methods [e.g., ultraviolet(UV) spectroscopy, infrared(IR) spectroscopy, nuclear magnetic resonance(NMR) spectroscopy, and high-resolution electrospray ionization mass spectrometry(HR-ESI-MS)]. Twelve compounds were yielded and identified from Aspergillus sp. CCH-1E, which are chermesinone H(1), chermesinone I(2), chermesinone B(3), 8,11-didehydrochermesinone B(4), chermesinone C(5), chermesinone A(6), chevalone B(7), barbacenic acid(8), 3,6,8-trihydroxy-3,5,7-trimethyl-3,4-dihydroisocoumarin(9), 5-hydroxy-2-methoxy-7-methyl-1,4-naphthoquinone(10), 1-hydroxy-6,8-dimethoxy-3-methylanthracene-9,10-dione(11), and 7-drimen-9α,11,12-triol(12). Among them, compounds 1 and 2 are new compounds. The growth inhibition effects of all compounds were evaluated against non-small cell lung cancer cell lines A549 and NCI-H1650, as well as human cervical cancer cell line HeLa by using methylthiazolyldiphenyl-tetrazolium bromide(MTT). Compound 7 significantly inhibited the growth of three tumor cells with the IC_(50) values of 1.22-2.43 µmol·L~(-1), respectively. Compounds 1-6 showed moderate cell growth inhibition with the IC_(50) values of 16.24-35.28 µmol·L~(-1).
Assuntos
Aspergillus , Catharanthus , Metabolismo Secundário , Humanos , Aspergillus/química , Aspergillus/metabolismo , Catharanthus/microbiologia , Catharanthus/química , Linhagem Celular Tumoral , Estrutura Molecular , Endófitos/química , Proliferação de Células/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Cromatografia Líquida de Alta PressãoRESUMO
Background: Aspergillus cristatus was a filamentous fungus that produced sexual spores under hypotonic stress and asexual spores under hypertonic stress. It could be useful for understanding filamentous fungi's sporulation mechanism. Previously, we conducted functional studies on Achog1, which regulated the hyperosmotic glycerol signaling (HOG) pathway and found that SI65_02513 was significantly downregulated in the transcriptomics data of ΔAchog1 knockout strain. This gene was located at multiple locations in the HOG pathway, indicating that it might play an important role in the HOG pathway of A. cristatus. Furthermore, the function of this gene had not been identified in Aspergillus fungi, necessitating further investigation. This gene's conserved domain study revealed that it has the same protein tyrosine phosphatases (PTPs) functional domain as Saccharomyces cerevisiae, hence SI65_02513 was named Acptp2,3. Methods: The function of this gene was mostly validated using gene knockout and gene complementation approaches. Knockout strains exhibited sexual and asexual development, as well as pigments synthesis. Morphological observations of the knockout strain were carried out under several stress conditions (osmotic stress, oxidative stress, Congo Red, and sodium dodecyl sulfate (SDS). Real-time fluorescence polymerase chain reaction (PCR) identified the expression of genes involved in sporulation, stress response, and pigments synthesis. Results: The deletion of Acptp2,3 reduced sexual and asexual spore production by 4.4 and 4.6 times, demonstrating that Acptp2,3 positively regulated the sporulation of A. cristatus. The sensitivity tests to osmotic stress revealed that ΔAcptp2,3 strains did not respond to sorbitol-induced osmotic stress. However, ΔAcptp2.3 strains grew considerably slower than the wild type in high concentration sucrose medium. The ΔAcptp2,3 strains grew slower than the wild type on media containing hydrogen peroxide, Congo red, and SDS. These findings showed that Acptp2,3 favorably controlled osmotic stress, oxidative stress, and cell wall-damaging chemical stress in A. cristatus. Deleting Acptp2,3 resulted in a deeper colony color, demonstrating that Apctp2,3 regulated pigment synthesis in A. cistatus. The expression levels of numerous stress-and pigments-related genes matched the phenotypic data. Conclusion: According to our findings, Acptp2,3 played an important role in the regulation of sporulation, stress response, and pigments synthesis in A. cristatus. This was the first study on the function of PTPs in Aspergillus fungi.
Assuntos
Aspergillus , Proteínas Fúngicas , Pressão Osmótica , Esporos Fúngicos , Esporos Fúngicos/genética , Esporos Fúngicos/metabolismo , Aspergillus/metabolismo , Aspergillus/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Pigmentos Biológicos/metabolismo , Pigmentos Biológicos/biossíntese , Estresse Fisiológico , Regulação Fúngica da Expressão Gênica , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Tirosina Fosfatases/genética , Técnicas de Inativação de Genes , Estresse Oxidativo , Vermelho Congo/farmacologiaRESUMO
Five new sorbicillinoid derivatives, including (±)-aspersorbicillin A [(±)-1], a pair of enantiomers at C-9, and aspersorbicillins B-D (2-4), together with two known analogs (5 and 6) were isolated from the endophytic fungus Aspergillus aculeatus TE-65L. Their structures including absolute configurations were determined by detailed spectroscopic analyses and electronic circular dichroism calculations. The herbicidal activity of sorbicillinoids on the germ and radicle elongation of various weed types was reported for the first time. Compound 1 displayed significant herbicidal activity against Eleusine indica germ elongation (IC50 = 28.8 µg/mL), while compound 6 inhibited radicle elongation (IC50 = 25.6 µg/mL). Both were stronger than those of glyphosate (66.2 and 30.9 µg/mL, respectively). Further transcriptomic and LC-MS/MS metabolomic analysis indicated that 6 induced the transcriptional expressions of genes related to the lignin biosynthetic pathway, resulting in lignin accumulation. Transmission electron microscopy confirmed the cell wall thickening of seeds treated with 6, suggesting weed growth inhibition. This study reveals new lead compounds for fabricating natural herbicides and expands the agricultural use of sorbicillinoid analogs.
Assuntos
Aspergillus , Herbicidas , Lignina , Aspergillus/metabolismo , Aspergillus/genética , Aspergillus/efeitos dos fármacos , Aspergillus/química , Herbicidas/farmacologia , Herbicidas/química , Herbicidas/metabolismo , Lignina/química , Lignina/metabolismo , Lignina/farmacologia , Estrutura Molecular , Sementes/química , Sementes/metabolismo , Sementes/microbiologiaRESUMO
Aflatoxins are the most dangerous mycotoxins for food safety. They are mainly produced by Aspergillus flavus, A. parasiticus, and A. minisclerotigenes. The latter, an understudied species, was the main culprit for outbreaks of fatal aflatoxicosis in Kenya in the past. To determine specific genetic characteristics of these Aspergillus species, their genomes are comparatively analyzed. Differences reflecting the typical habitat are reported, such as an increased number of carbohydrate-active enzymes, including enzymes for lignin degradation, in the genomes of A. minisclerotigenes and A. parasiticus. Further, variations within the aflatoxin gene clusters are described, which are related to different chemotypes of aflatoxin biosynthesis. These include a substitution within the aflL gene of the A. parasiticus isolate, which leads to the translation of a stop codon, thereby switching off the production of the group 1 aflatoxins B1 and G1. In addition, we demonstrate that the inability of the A. minisclerotigenes isolates to produce group G aflatoxins is associated with a 2.2 kb deletion within the aflF and aflU genes. These findings reveal a relatively high genetic homology among the three Aspergillus species investigated. However, they also demonstrate consequential genetic differences that have an important impact on risk-assessment and food safety.
Assuntos
Aflatoxinas , Aspergillus , Aflatoxinas/biossíntese , Aflatoxinas/genética , Aflatoxinas/metabolismo , Aspergillus/genética , Aspergillus/metabolismo , Aspergillus flavus/genética , Aspergillus flavus/metabolismo , Genoma Fúngico , Ecossistema , Família Multigênica , Filogenia , Especificidade da EspécieRESUMO
Fungal secondary metabolites play a highly significant role in crop protection, which is related to their antifungal activity against agriculturally important phytopathogens. In fact, plant diseases caused by fungi including species belonging to the genera of Alternaria, Botrytis, and Fusarium have become increasingly serious affecting crop yield and quality. Hence, there is increasing awareness by the scientific community of the importance of exploiting fungal products for finding new compounds able to inhibit phytopathogens. In this study several drimane-type sesquiterpenes have been detected for the first time as products of Aspergillus xerophilus by GC-MS analysis of the organic extracts obtained from the mycelia and culture filtrates of the fungus grown on two different substrates. Seven pure drimane-type sesquiterpenes were also isolated and identified by spectroscopic methods. The inhibitory effects of the pure compounds have been investigated against three phytopathogenic fungi of agrarian crops (i.e., Botrytis cinerea, Alternaria alternata, and Fusarium oxysporum f. sp. pisi). Among the drimane-type sesquiterpenes isolated in this study, 9,11-dihydroxy-6-oxodrim-7-ene is the most active against the three phytopathogens. Our findings also reveal the high sensitivity of A. alternata to the isolated compounds. These results pave the way for future applications in agriculture of both A. xerophilus and its metabolites.
Assuntos
Alternaria , Aspergillus , Botrytis , Fungicidas Industriais , Fusarium , Doenças das Plantas , Metabolismo Secundário , Aspergillus/metabolismo , Aspergillus/efeitos dos fármacos , Aspergillus/química , Alternaria/efeitos dos fármacos , Alternaria/metabolismo , Alternaria/química , Fusarium/efeitos dos fármacos , Fusarium/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Botrytis/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Fungicidas Industriais/metabolismo , Produtos Agrícolas/microbiologia , Cromatografia Gasosa-Espectrometria de Massas , Sesquiterpenos/farmacologia , Sesquiterpenos/metabolismo , Sesquiterpenos/químicaRESUMO
Fungal diseases could severely harm agricultural productions. To develop new antifungal agents, based on the Global Natural Products Social Molecular Networking, typical bromine isotope peak ratios, and ultraviolet absorptions, cultivation of the soft coral-derived endophytic fungi Aspergillus terreus EGF7-0-1 with NaBr led to the targeted isolation of 14 new brominated aromatic butenolides (1-14) and six known analogues (15-20). Their structures were elucidated by extensive spectroscopic analysis and quantum chemical calculations. Compounds 1-14 exhibited wildly antifungal activities (against Colletotrichum gloeosporioides, Pestalotiopsis microspora, Fusarium oxysporum f. sp. cubense, Botrytis cinerea, and Diaporthe phoenicicola). The bioassay results showed that compounds 1-14 exhibited excellent antifungal activities against C. gloeosporioides, with concentration for 50% of maximal effect (EC50) values from 2.72 to 130.41 nM. The mechanistic study suggests that compound 1 may disrupt nutrient signaling pathways by reducing the levels of metabolites, such as carbohydrates, lipids, and amino acids, leading to an increase in low-density granules and a decrease in high-density granules in the cytoplasm, accompanied by numerous vacuoles, thereby inhibiting the growth of C. gloeosporioides. Monobrominated γ-butenolide 1 may be expected to exploit a novel agriculturally antifungal leading drug. Meanwhile, compound M1 has conformed antifugual activities against C. gloeosporioides by papayas in vivo.
Assuntos
4-Butirolactona , Aspergillus , Fungicidas Industriais , Aspergillus/metabolismo , Aspergillus/efeitos dos fármacos , Aspergillus/química , 4-Butirolactona/análogos & derivados , 4-Butirolactona/química , 4-Butirolactona/farmacologia , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Estrutura Molecular , Colletotrichum/efeitos dos fármacos , Halogenação , Testes de Sensibilidade Microbiana , Antifúngicos/farmacologia , Antifúngicos/químicaRESUMO
Aspergillus carbonarius, a common food-contaminating fungus, produces ochratoxin A (OTA) and poses a risk to human health. This study aimed to assess the inhibitory activity of tea tree essential oil and its main components, Terpene-4-ol (T4), α-terpineol (αS), and 3-carene (3C) against A. carbonarius. The study showed αS and T4 were the main antifungal components of tea tree essential oil, which primarily inhibit A. carbonarius growth through cell membrane disruption, reducing antioxidant enzyme activities (catalase, peroxidase, superoxide dismutase) and interrupting the tricarboxylic acid cycle. Furthermore, αS and T4 interacted with enzymes related to OTA biosynthesis. Molecular docking and molecular dynamics show that they bound mainly to P450 with a minimum binding energy of -7.232 kcal/mol, we infered that blocking the synthesis of OTA precursor OTß. Our hypothesis was preliminarily verified by the detection of key substances in the OTA synthesis pathway. The results of UHPLC-QTOF-MS2 analysis demonstrated that T4 achieved a degradation rate of 43 % for OTA, while αS reached 29.6 %, resulting in final breakdown products such as OTα and phenylalanine. These results indicated that α-terpinol and Terpene-4-ol have the potential to be used as naturally safe and efficient preservatives or active packaging to prevent OTA contamination.
Assuntos
Aspergillus , Monoterpenos Cicloexânicos , Simulação de Acoplamento Molecular , Ocratoxinas , Terpenos , Ocratoxinas/metabolismo , Ocratoxinas/biossíntese , Aspergillus/metabolismo , Aspergillus/efeitos dos fármacos , Terpenos/metabolismo , Óleo de Melaleuca/farmacologia , Óleo de Melaleuca/química , Monoterpenos/farmacologia , Monoterpenos/metabolismo , Antifúngicos/farmacologia , Antifúngicos/química , Monoterpenos BicíclicosRESUMO
Lovastatin has received interest for its potential therapeutic use in treating numerous diseases, for example, the blood cholesterol level by restraining hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase. The research utilized the fungal growth bioassay technique to disengage and evaluate filamentous organism for the lovastatin creation. The clever type of Aspergillus terreus (KF971363.1) was embraced for lovastatin creation by solid-state fermentation (SSF). Lovastatin production was optimized using physiological parameters such as pH and temperature at SSF. The addition of nitrogen source enhanced the production of lovastatin by the breakdown of lignocellulose that improved the production of lovastatin. The research verified a yeast growth inhibition bioassay approach, in addition to thin-layer chromatography and liquid chromatography-mass spectrometry (LC-MS). All of these techniques were used to confirm lovastatin production. The purified extract subjected to the TLC analysis showed retention factor (Rf) value of 0.73. Moreover, the inhibition bioassay method reassures the lovastatin production by comparing the zone of inhibition against C. albicans.
Assuntos
Antifúngicos , Aspergillus , Fermentação , Lovastatina , Lovastatina/biossíntese , Lovastatina/farmacologia , Aspergillus/metabolismo , Aspergillus/efeitos dos fármacos , Aspergillus/crescimento & desenvolvimento , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Cromatografia em Camada Fina , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Concentração de Íons de Hidrogênio , Temperatura , Espectrometria de MassasRESUMO
The production of alternative proteins is of great significance in the mitigation of food problems. This study proposes an integrated approach including protein extraction, enzymatic hydrolysis, and fermentation to produce both plant proteins and single-cell proteins as alternative proteins from tobacco leaves, a highly-abundant and protein-rich agricultural waste. Alkaline extraction of proteins before polysaccharide hydrolysis was found to be preferable for increasing the yields of plant proteins and mono-sugars. The combined use of pectinase-rich enzymes from Aspergillus brunneoviolaceus and hemicellulase-rich enzymes from Penicillium oxalicum achieved the release of 80.7 % of the sugars after 72 h. Cutaneotrichosporon cutaneum could simultaneously utilize multiple sugars, including galacturonic acid, in the enzymatic hydrolysate to produce single-cell proteins. Via this approach, 43.54 g crude proteins of high protein contents and rich in essential amino acids can be produced from 100.00 g waste tobacco leaves, providing a promising strategy for its valorization.
Assuntos
Nicotiana , Pectinas , Folhas de Planta , Proteínas de Plantas , Nicotiana/metabolismo , Pectinas/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/química , Proteínas de Plantas/metabolismo , Hidrólise , Poligalacturonase/metabolismo , Fermentação , Glicosídeo Hidrolases/metabolismo , Aspergillus/metabolismo , Álcalis , Penicillium/metabolismo , Proteínas Fúngicas/metabolismo , Resíduos , Proteínas AlimentaresRESUMO
Endophytic fungi have been shown to synthesize bioactive secondary metabolites, some of which promote plant growth through various mechanisms. In our previous study, endophytic fungi were isolated from mango trees (Mangifera indica L.). The present study examined fifty endophytic fungal isolates for mineral solubilization activity, ammonia production, and siderophore production. It was shown that these isolates could produce phytohormones indole-3-acetic acid and gibberellic acid, as well as inhibit plant pathogens, specifically Colletotrichum gloeosporioides and Lasiodiplodia theobromae. The results showed that all the isolated fungal endophytes exhibited various activities. Based on the findings, two fungal endophytes-Aureobasidium pullulans CY.OS 13 and Aspergillus tamarii CY.OS 144-were selected for dual inoculation in chili plants under pot-scale conditions to investigate their potential to improve growth-related traits such as seed germination, shoot and root length, biomass, and chlorophyll content. Seed treated with A. pullulans CY.OS 13 and/or A. tamarii CY.OS 144 showed a significant (p < 0.05) increase in seed germination and growth parameters of chili plants grown under pot-scale conditions. Particularly, chili plants whose seeds were injected with a combination of the two selected endophytic fungi showed the highest plant development traits. Therefore, the selected endophytic fungi have the potential to be used as biofertilizers, especially when combined. They could eventually replace chemical fertilizers because they are environmentally friendly, beneficial to humans, and can even promote sustainable agriculture.
Assuntos
Colletotrichum , Endófitos , Ácidos Indolacéticos , Mangifera , Reguladores de Crescimento de Plantas , Endófitos/isolamento & purificação , Endófitos/metabolismo , Mangifera/microbiologia , Reguladores de Crescimento de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Colletotrichum/crescimento & desenvolvimento , Giberelinas/metabolismo , Raízes de Plantas/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Sideróforos/metabolismo , Desenvolvimento Vegetal , Germinação , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Ascomicetos/isolamento & purificação , Fungos/isolamento & purificação , Fungos/classificação , Fungos/metabolismo , Fungos/crescimento & desenvolvimento , Sementes/microbiologia , Sementes/crescimento & desenvolvimento , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Aspergillus/isolamento & purificação , Clorofila/metabolismo , Amônia/metabolismo , Capsicum/microbiologia , Capsicum/crescimento & desenvolvimento , BiomassaRESUMO
The global incidence of invasive fungal infections (IFIs) has increased over the past few decades, mainly in immunocompromised patients, and is associated with high mortality and morbidity. Aspergillus fumigatus is one of the most common and deadliest IFI pathogens. Major hurdles to treating fungal infections remain the lack of rapid and definitive diagnosis, including the frequent need for invasive procedures to provide microbiological confirmation, and the lack of specificity of structural imaging methods. To develop an Aspergillus-specific positron emission tomography (PET) imaging agent, we focused on fungal-specific sugar metabolism. We radiolabeled cellobiose, a disaccharide known to be metabolized by Aspergillus species, and synthesized 2-deoxy-2-[18F]fluorocellobiose ([18F]FCB) by enzymatic conversion of 2-deoxy-2-[18F]fluoroglucose ([18F]FDG) with a radiochemical yield of 60 to 70%, a radiochemical purity of >98%, and 1.5 hours of synthesis time. Two hours after [18F]FCB injection in A. fumigatus pneumonia as well as A. fumigatus, bacterial, and sterile inflammation myositis mouse models, retained radioactivity was only seen in foci with live A. fumigatus infection. In vitro testing confirmed production of ß-glucosidase enzyme by A. fumigatus and not by bacteria, resulting in hydrolysis of [18F]FCB into glucose and [18F]FDG, the latter being retained by the live fungus. The parent molecule was otherwise promptly excreted through the kidneys, resulting in low background radioactivity and high target-to-nontarget ratios at A. fumigatus infectious sites. We conclude that [18F]FCB is a promising and clinically translatable Aspergillus-specific PET tracer.
Assuntos
Aspergillus fumigatus , Celobiose , Tomografia por Emissão de Pósitrons , Animais , Tomografia por Emissão de Pósitrons/métodos , Celobiose/metabolismo , Aspergillus fumigatus/metabolismo , Camundongos , Aspergilose/diagnóstico por imagem , Fluordesoxiglucose F18/química , Aspergillus/metabolismo , Distribuição Tecidual , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/metabolismoRESUMO
Considering an ever-growing global population, which hit 8 billion people in the fall of 2022, it is essential to find solutions to avoid croplands competition between human food and animal feed. Agricultural co-products such as soybean meals have become important components of the circular economy thanks to their use in animal feed. Their implementation was made possible by the addition of exogenous enzymes in the diet of monogastric animals, especially fungal carbohydrate-active enzymes (CAZymes). Here, we describe a time-course production and analysis of Aspergillus terreus secretomes for the identification of CAZymes able to enhance the digestibility of soybean meals. Functional assays revealed that the release of nutrients and the degradation of pectins in soybean meals can be tightly interconnected. Using a comparative proteomics approach, we identified several fungal pectin-degrading enzymes leading to increased assimilable nutrients in the soluble fraction of soybean meals. Our results reinforce the importance of deconstructing pectic polysaccharides in feedstuffs and contribute to sharpen our understanding of the fungal enzymatic interplays involved in pectin hydrolysis.IMPORTANCEIn the present study, we developed a strategy to identify the key fungal enzymatic activities involved in the improvement of soybean meal (SBM) digestibility. Our data unravel the importance of pectin degradation for the release of nutrients from SBM and provide some insights regarding the degradation of rhamnogalacturonan-I (RG-I) by ascomycetes. Indeed, the hydrolysis of pectins and RG-I by human microbiota is well documented in the literature, but our knowledge of the fungal CAZymes at play for the degradation of soybean pectins remains hitherto underexplored. Due to its wide use in animal feed, improving the digestibility of SBM by enzymatic treatments is a current challenge for feed additive suppliers. Since non-starch polysaccharides and pectins have often been reported for their anti-nutritional role in SBM, we believe this study will provide new avenues toward the improvement of enzymatic cocktails for animal nutrition and health.
Assuntos
Ração Animal , Aspergillus , Glycine max , Pectinas , Aspergillus/metabolismo , Aspergillus/enzimologia , Pectinas/metabolismo , Glycine max/metabolismo , Ração Animal/análise , Proteínas Fúngicas/metabolismo , DigestãoRESUMO
Methanol reportedly stimulates citric acid (CA) production by Aspergillus niger and A. tubingensis; however, the underlying mechanisms remain unclear. Here, we elucidated the molecular functions of the citrate exporter gene cexA in relation to CA production by A. tubingensis WU-2223L. Methanol addition to the medium containing glucose as a carbon source markedly increased CA production by strain WU-2223L by 3.38-fold, resulting in a maximum yield of 65.5 g/L, with enhanced cexA expression. Conversely, the cexA-complementing strain with the constitutive expression promoter Ptef1 (strain LhC-1) produced 68.3 or 66.7 g/L of CA when cultivated without or with methanol, respectively. Additionally, strain LhC-2 harboring two copies of the cexA expression cassette produced 80.7 g/L of CA without methanol addition. Overall, we showed that cexA is a target gene for methanol in CA hyperproduction by A. tubingensis WU-2223L. Based on these findings, methanol-independent CA-hyperproducing strains, LhC-1 and LhC-2, were successfully generated.
Assuntos
Aspergillus , Ácido Cítrico , Metanol , Metanol/metabolismo , Ácido Cítrico/metabolismo , Aspergillus/genética , Aspergillus/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regiões Promotoras Genéticas , Regulação Fúngica da Expressão Gênica , Fermentação , Glucose/metabolismoRESUMO
Saccharomyces cerevisiae CCMA 0159 is reported as a promising biocontrol agent against ochratoxin A (OTA)-producing fungi in coffee. Coffea arabica and Coffea canephora (var. Conilon or Robusta) are the most widely consumed coffee species around the world, cultivated in tropical and subtropical regions, each exhibiting distinct physicochemical and sensory characteristics. The objective of this study was to compare the growth and OTA production by Aspergillus carbonarius, A. ochraceus, and A. westerdijkiae in C. arabica and C. canephora, along with assessing the efficiency of S. cerevisiae CCMA 0159 in biocontrolling ochratoxigenic fungi in both coffee varieties. A. carbonarius exhibited a higher growth rate and OTA production in both coffee varieties, with C. canephora showing particular susceptibility. Conversely, A. ochraceus and A. westerdijkiae demonstrated lower growth and OTA production. S. cerevisiae was effective in biocontrolling the fungal isolates, inhibiting over 80 % of A. carbonarius growth in both coffee varieties. Among the mechanisms of action of the biological control agent, the production of volatile organic compounds stands out. The results of this study confirm the significant potential of S. cerevisiae CCMA 0159 as a biocontrol agent against Aspergillus for application in coffee-producing areas.
Assuntos
Aspergillus , Coffea , Ocratoxinas , Saccharomyces cerevisiae , Ocratoxinas/biossíntese , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Coffea/microbiologia , Contaminação de Alimentos/prevenção & controle , Contaminação de Alimentos/análise , Café/microbiologia , Agentes de Controle Biológico , Microbiologia de AlimentosRESUMO
The fruit processing industry is responsible for disposing of huge amounts of byproducts, especially fruit peels (FPs), which are often discarded in landfills. Using FPs in biotechnological processes contributes to a circular economy, reducing the environmental burden of FPs and increasing the revenue of the fruit processing industry. This study was focused on upgrading the nutritional value of orange (OPs) and banana (BPs) peels by solid-state fermentation (SSF) with filamentous fungi. SSF factors (moisture, fermentation time, inoculum size, ammonium sulfate (AS), and corn steep liquor (CSL)) and fungi species (Aspergillus ibericus and Rhizopus oryzae) were studied by a variable screening Plackett-Burman design. Both fungi grew on untreated FPs, increasing their protein content and antioxidant activity. Moisture, AS, and CSL were further studied by a Box-Behnken design with A. ibericus. Fermented OPs at 70% moisture and 0.005 g/g AS increased their protein content by 200%, whereas BPs at 70% moisture and 0.005 g/g CSL increased by 123%. Fermented peels were enriched in protein, fiber, and minerals, with a low content of carbohydrates and soluble sugars. Fermented OPs and BPs showed higher antioxidant activity than unfermented peels. The SSF of these FPs is an innovative approach that contributes to obtaining rich nutrient-fermented peels for food.
Assuntos
Fermentação , Frutas , Valor Nutritivo , Rhizopus oryzae , Frutas/microbiologia , Frutas/química , Frutas/metabolismo , Rhizopus oryzae/metabolismo , Aspergillus/metabolismo , Musa/microbiologia , Antioxidantes/metabolismo , Citrus sinensis/microbiologia , Citrus sinensis/químicaRESUMO
Fungal infections pose severe and potentially lethal threats to plant, animal, and human health. Ergosterol has served as the primary target for developing antifungal medications. However, many antifungal drugs remain highly toxic to humans due to similarity in cell membrane composition between fungal and animal cells. Iturin A, lipopeptide produced by Bacillus subtilis, efficiently inhibit various fungi, but demonstrated safety in oral administration, indicating the existence of targets different from ergosterol. To pinpoint the exact antifungal target of iturin A, we used homologous recombination to knock out and overexpress erg3, a key gene in ergosterol synthesis. Saccharomyces cerevisiae and Aspergillus carbonarius were transformed using the LiAc/SS-DNNPEG and Agrobacterium-mediated transformation (AMT), respectively. Surprisingly, increasing ergosterol content did not augment antifungal activity. Furthermore, iturin A's antifungal activity against S. cerevisiae was reduced while it pre-incubation with voltage-gated potassium (Kv) channel inhibitor, indicating that Kv activation was responsible for cell death. Iturin A was found to activate the Kv protein, stimulating K+ efflux from cell. In vitro tests confirmed interaction between iturin A and Kv protein. This study highlights Kv as one of the precise targets of iturin A in its antifungal activity, offering a novel target for the development of antifungal medications.
Assuntos
Antifúngicos , Bacillus subtilis , Peptídeos Cíclicos , Saccharomyces cerevisiae , Antifúngicos/farmacologia , Antifúngicos/química , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/química , Bacillus subtilis/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Lipopeptídeos/farmacologia , Canais de Potássio/metabolismo , Canais de Potássio/genética , Ergosterol , Aspergillus/efeitos dos fármacos , Aspergillus/metabolismo , Potássio/metabolismo , Testes de Sensibilidade MicrobianaRESUMO
UV-C irradiation can maintain fruit quality by inducing fruit disease resistance and reducing decay during storage. Grape (Vitis Vinifera L.) was exposed to 2.4 kJ m-2 UV-C irradiation then inoculated with Aspergillus carbonarius to investigate the changes in nutritional quality, defense related substances and enzyme activities. Postharvest UV-C irradiation can increased the levels of defense-related substances and enzyme activities, such as phenols, flavanols, lignin, proline, glutathione, phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO), and ß-1,3-glucanase (GLU). In addition, Resveratrol plays an important role in grape resistance to A. carbonarius infection through further verification by gene expression levels, the transcription factors VvWRKY24 and VvMYB14 are highly correlated with the regulation of VvSTS gene expression. This study revealed the molecular mechanism of postharvest grape fruit response to UV-C irradiation and the defense mechanism against black rot, and provided a theoretical basis for postharvest grape storage and preservation technology.