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Biotechnology For Biofuels and... May 2024Aspergillus tubingensis is a citric acid-producing fungus that can utilize sugars in hydrolysate of lignocellulosic biomass such as sugarcane bagasse and, unlike A....
BACKGROUND
Aspergillus tubingensis is a citric acid-producing fungus that can utilize sugars in hydrolysate of lignocellulosic biomass such as sugarcane bagasse and, unlike A. niger, does not produce mycotoxins. To date, no attempt has been made to model its metabolism at genome scale.
RESULTS
Here, we utilized the whole-genome sequence (34.96 Mb length) and the measured biomass composition to reconstruct a genome-scale metabolic model (GSMM) of A. tubingensis DJU120 strain. The model, named iMK1652, consists of 1652 genes, 1657 metabolites and 2039 reactions distributed over four cellular compartments. The model has been extensively curated manually. This included removal of dead-end metabolites and generic reactions, addition of secondary metabolite pathways and several transporters. Several mycotoxin synthesis pathways were either absent or incomplete in the genome, providing a genomic basis for the non-toxinogenic nature of this species. The model was further refined based on the experimental phenotypic microarray (Biolog) data. The model closely captured DJU120 fermentative data on glucose, xylose, and phosphate consumption, as well as citric acid and biomass production, showing its applicability to capture citric acid fermentation of lignocellulosic biomass hydrolysate.
CONCLUSIONS
The model offers a framework to conduct metabolic systems biology investigations and can act as a scaffold for integrative modelling of A. tubingensis.
PubMed: 38807234
DOI: 10.1186/s13068-024-02506-4 -
PloS One 2024In this investigation, we explore the harnessing of bamboo shoot residues (BSR) as a viable source for ruminant feed through fungal treatment, with the overarching...
In this investigation, we explore the harnessing of bamboo shoot residues (BSR) as a viable source for ruminant feed through fungal treatment, with the overarching objective of elevating feed quality and optimizing bamboo shoot utilization. The white-rot fungi (Wr.fungi), Aspergillus niger (A.niger), and its co-cultures (A.niger&Wr.fungi) were employed to ferment BSR. And the impact of different fermentation methods and culture time on the chemical composition (Crude protein Ash, neutral detergent fibre and acid detergent fibers), enzyme activity (Cellulase, Laccase, Filter paperase and Lignin peroxidase activities), and rumen digestibility in vitro were assessed. The findings reveal a nota ble 30.39% increase in crude protein in fermented BSR, accompanied by respective decreases of 13.02% and 17.31% in acid detergent fiber and neutral detergent fibre content. Enzyme activities experienced augmentation post-fermentation with A.niger&Wr.fungi. Specifically, the peak Cellulase, Laccase, and Lignin peroxidase activities for BSR with Wr.fungi treatment reached 748.4 U/g, 156.92 U/g, and 291.61 U/g, respectively, on the sixth day of fermentation. Concurrently, NH3-N concentration exhibited an upward trend with prolonged fermentation time. Total volatile fatty acids registered a decline, and the Acetate/Propionate ratio reached its nadir after 6 days of fermentation under the A.niger&Wr.fungi treatment. These outcomes furnish a theoretical foundation for the development of ruminant feeds treated via fungal co-culture.
Topics: Animals; Animal Feed; Fermentation; Ruminants; Aspergillus niger; Plant Shoots; Rumen; Fungi
PubMed: 38805421
DOI: 10.1371/journal.pone.0302185 -
Biotech (Basel (Switzerland)) May 2024The enzymatic hydrolysis of agricultural residues like wheat bran enables the valorization of otherwise unused carbon sources for biotechnological processes. The...
The enzymatic hydrolysis of agricultural residues like wheat bran enables the valorization of otherwise unused carbon sources for biotechnological processes. The co-culture of and with wheat bran particles as substrate produces an enzyme set consisting of xylanases, amylases, and cellulases that is suitable to degrade lignocellulosic biomass to sugar monomers (D-glucose, D-xylose, and L-arabinose). An integrated one-pot process for enzyme production followed by hydrolysis in stirred tank bioreactors resulted in hydrolysates with overall sugar concentrations of 32.3 g L and 24.4 g L at a 25 L and a 1000 L scale, respectively, within 86 h. Furthermore, the residual solid biomass consisting of fermented wheat bran with protein-rich fungal mycelium displays improved nutritional properties for usage as animal feed due to its increased content of sugars, protein, and fat.
PubMed: 38804297
DOI: 10.3390/biotech13020015 -
Nature Communications May 2024Bacterial-fungal interactions influence microbial community performance of most ecosystems and elicit specific microbial behaviours, including stimulating specialised...
Bacterial-fungal interactions influence microbial community performance of most ecosystems and elicit specific microbial behaviours, including stimulating specialised metabolite production. Here, we use a co-culture experimental evolution approach to investigate bacterial adaptation to the presence of a fungus, using a simple model of bacterial-fungal interactions encompassing the bacterium Bacillus subtilis and the fungus Aspergillus niger. We find in one evolving population that B. subtilis was selected for enhanced production of the lipopeptide surfactin and accelerated surface spreading ability, leading to inhibition of fungal expansion and acidification of the environment. These phenotypes were explained by specific mutations in the DegS-DegU two-component system. In the presence of surfactin, fungal hyphae exhibited bulging cells with delocalised secretory vesicles possibly provoking an RlmA-dependent cell wall stress. Thus, our results indicate that the presence of the fungus selects for increased surfactin production, which inhibits fungal growth and facilitates the competitive success of the bacterium.
Topics: Bacillus subtilis; Aspergillus niger; Lipopeptides; Adaptation, Physiological; Peptides, Cyclic; Hyphae; Microbial Interactions; Bacterial Proteins; Coculture Techniques; Mutation; Cell Wall
PubMed: 38802389
DOI: 10.1038/s41467-024-48812-1 -
Saudi Journal of Biological Sciences Jul 2024The inorganic colour layer based on iron oxide is affected by microorganisms (fungi) and leads to its deterioration due to feeding on the mineral elements through the...
The inorganic colour layer based on iron oxide is affected by microorganisms (fungi) and leads to its deterioration due to feeding on the mineral elements through the chemical composition of the colour in the presence of a suitable environment (medium). Damage occurs as a result of heavy metal elements being removed from the colour, leading to a defect in the chemical composition and the fading of the colours. The current study showed the effect of the different types of the most common fungi on oil paintings ( and ) after cultivating the different types of fungi and obtaining pure colonies for each fungus separately and conducting a fungal infection on experimental samples with preparing the old techniques, coloured with hematite red and goethite yellow. Each colour is mixed with different proportions of linseed oil (1, 2, 3). They were aged artificially and incubated at a temperature of 26 degrees and examined periodically until the fungi appeared on the surface in the form of colour spots ranging from very dark (severe infestation) to light (low infestation). The change in chemical composition was measured by Raman and EDX analyses of the samples before and after infection. Fungi showed the appearance of spoilage products from metal sulfides and metal carboxylates. The iron oxide ion decreased in both the red and the yellow colours, leading to a change after the fungal infection. Examination of the morphological surface using SEM, USB and measurement of colour change showed the change in the red colour more than the yellow and scattering of green and black colour dots on the surface of the sample. Correlation and Simple Linear Regression were applied for each colour before and after besides both colours together. It was found that these colours appeared around some of the fungal colonies as a result of the activities. Fungal species of some strains reduced Fe to Fe . This provides new insights into the role of microorganisms in the deterioration of painted surfaces.
PubMed: 38799718
DOI: 10.1016/j.sjbs.2024.104004 -
Saudi Pharmaceutical Journal : SPJ :... Jun 2024The menace of microbial resistance and re-emerging disease is still a problem for healthcare givers globally, and the need for newer sources of potent antibiotics has...
The menace of microbial resistance and re-emerging disease is still a problem for healthcare givers globally, and the need for newer sources of potent antibiotics has become paramount. This study investigated the antimicrobial and antiulcer activities of Streptomyces isolate SOM013. Streptomyces isolates were cultivated and purified following standard microbiological protocols. Secondary metabolites were recovered and characterized from Streptomyces isolate SOM013 via broth fermentation and extraction. Varying concentrations (0.5 mg/mL, 0.025 mg/mL and 0.0125 mg/mL) of the SOM013 extract were used for antimicrobial screening against resistant bacteria and medically important fungi (methicillin-resistant , Oxacillin resistant , , extended broad-spectrum resistant , and ). The antiulcer activity of the SOM013 was also examined in a methanol-induced gastric ulcer animal model. A total of 23 Streptomyces spp were recovered from the study. Methanolic extract of the SOM013 isolates was more potent across the clinical test microorganisms compared to water extract. The antimicrobial activity was dose dependent, with methanolic extract at 0.05 g/mL displaying the highest zone of inhibition (18.8 ± 0.3 mm) when tested against extended broad-spectrum resistant . Further, the extract's ulcer index and protection efficacy were significant as the concentration increased (P < 0.01). SOM013 isolate has a moderate antimicrobial and high antiulcer activity worthy of pharmacological exploration.
PubMed: 38799000
DOI: 10.1016/j.jsps.2024.102101 -
Journal of Fungi (Basel, Switzerland) May 2024Wooden Cultural Heritage (WCH) represents a significant portion of the world's historical and artistic heritage, consisting of immovable and movable artefacts. Despite... (Review)
Review
Once upon a Time, There Was a Piece of Wood: Present Knowledge and Future Perspectives in Fungal Deterioration of Wooden Cultural Heritage in Terrestrial Ecosystems and Diagnostic Tools.
Wooden Cultural Heritage (WCH) represents a significant portion of the world's historical and artistic heritage, consisting of immovable and movable artefacts. Despite the expertise developed since ancient times to enhance its durability, wooden artefacts are inevitably prone to degradation. Fungi play a pivotal role in the deterioration of WCH in terrestrial ecosystems, accelerating its decay and leading to alterations in color and strength. Reviewing the literature of the last 25 years, we aimed to provide a comprehensive overview of fungal diversity affecting WCH, the biochemical processes involved in wood decay, and the diagnostic tools available for fungal identification and damage evaluation. Climatic conditions influence the occurrence of fungal species in threatened WCH, characterized by a prevalence of wood-rot fungi (e.g., , ) in architectural heritage in temperate and continental climates and Ascomycota in indoor and harsh environments. More efforts are needed to address the knowledge fragmentation concerning biodiversity, the biology of the fungi involved, and succession in the degradative process, which is frequently centered solely on the main actors. Multidisciplinary collaboration among engineers, restorers, and life sciences scientists is vital for tackling the challenges posed by climate change with increased awareness. Traditional microbiology and culture collections are fundamental in laying solid foundations for a more comprehensive interpretation of big data.
PubMed: 38786721
DOI: 10.3390/jof10050366 -
RSC Advances May 2024Fungal contamination poses a persistent challenge to industries, particularly in food, healthcare, and clinical sectors, due to the remarkable resilience of fungi in...
Fungal contamination poses a persistent challenge to industries, particularly in food, healthcare, and clinical sectors, due to the remarkable resilience of fungi in withstanding conventional control methods. In this context, our research delves into the comparative efficacy of UV radiation and non-thermal plasma (NTP) on key foodborne fungal contaminants - , , , and . The study examined the impact of varying doses of UV radiation on the asexual spores of all mentioned fungal strains. Simultaneously, the study compared the effects of UV radiation and NTP on the metabolic activity of cells after spore germination and their subsequent germination ability. The results revealed that UV-C radiation (254 nm) did not significantly suppress the metabolic activity of cells after spore germination. In contrast, NTP exhibited almost 100% effectiveness on both selected spores and their subsequent germination, except for . In the case of , the effectiveness of UV-C and NTP was nearly comparable, showing only a 35% decrease in metabolic activity after 48 hours of germination, while the other strains (, , ) exhibited a reduction of more than 95%. SEM images illustrate the morphological changes in structure of all tested spores after both treatments. This study addresses a crucial gap in existing literature, offering insights into the adaptation possibilities of treated cells and emphasizing the importance of considering exposure duration and nutrient conditions (introduction of fresh medium). The results highlighted the promising antimicrobial potential of NTP, especially for filamentous fungi, paving the way for enhanced sanitation processes with diverse applications.
PubMed: 38784412
DOI: 10.1039/d4ra01689k -
Scientific Reports May 2024Silver nanoparticles (AgNPs) have gained much attention due to their unique physical, and chemical properties. Integration of phytochemicals in nanoformulation might...
Silver nanoparticles (AgNPs) have gained much attention due to their unique physical, and chemical properties. Integration of phytochemicals in nanoformulation might have higher applicability in healthcare. Current work demonstrates the synthesis of green AgNPs with O. gratissimum (gr-AgNPs) O. tenuiflorum (te-AgNPs) and O. americanum (am-AgNPs) followed by an evaluation of their antimicrobial and anticancer properties. SEM analysis revealed spherical-shaped particles with average particle sizes of 69.0 ± 5 nm for te-AgNPs, 46.9 ± 9 nm for gr-AgNPs, and 58.5 ± 18.7 nm for am-AgNPs with a polydispersity index below 0.4. The synthesized am-AgNPs effectively inhibited Klebsiella pneumonia, Escherichia coli, Staphylococcus aureus, Aspergillus niger, and Candida albicans with 23 ± 1.58 mm, 20 ± 1.68 mm, 22 ± 1.80 mm, 26 ± 1.85 mm, and 22 ± 1.40 nm of zone of inhibition respectively. Synthesized AgNPs also induced apoptotic cell death in MCF-7 in concentration-dependent manner. IC values for am-AgNPs, te-AgNPs, and gr-AgNPs were 14.78 ± 0.89 µg, 18.04 ± 0.63 and 15.41 ± 0.37 µg respectively which suggested that am-AgNPs were the most effective against cancer. At higher dose size (20 µg) AgNPs were equally effective to commercial standard Doxorubicin (DOX). In comparison to te-AgNPs and gr-AgNPs, am-AgNPs have higher in vitro anticancer and antimicrobial effects. The work reported Ocimum americanum for its anticancer properties with chemical profile (GCMS) and compared it with earlier reported species. The activity against microbial pathogens and selected cancer cells clearly depicted that these species have distinct variations in activity. The results have also emphasized on higher potential of biogenic silver nanoparticles in healthcare but before formulation of commercial products, detailed analysis is required with human and animal models.
Topics: Silver; Metal Nanoparticles; Humans; Green Chemistry Technology; Antineoplastic Agents; Ocimum; MCF-7 Cells; Microbial Sensitivity Tests; Plant Extracts; Anti-Infective Agents; Apoptosis; Particle Size
PubMed: 38777818
DOI: 10.1038/s41598-024-61946-y -
Scientific Reports May 2024The Martian surface and shallow subsurface lacks stable liquid water, yet hygroscopic salts in the regolith may enable the transient formation of liquid brines. This...
The Martian surface and shallow subsurface lacks stable liquid water, yet hygroscopic salts in the regolith may enable the transient formation of liquid brines. This study investigated the combined impact of water scarcity, UV exposure, and regolith depth on microbial survival under Mars-like environmental conditions. Both vegetative cells of Debaryomyces hansenii and Planococcus halocryophilus, alongside with spores of Aspergillus niger, were exposed to an experimental chamber simulating Martian environmental conditions (constant temperatures of about - 11 °C, low pressure of approximately 6 mbar, a CO atmosphere, and 2 h of daily UV irradiation). We evaluated colony-forming units (CFU) and water content at three different regolith depths before and after exposure periods of 3 and 7 days, respectively. Each organism was tested under three conditions: one without the addition of salts to the regolith, one containing sodium chlorate, and one with sodium perchlorate. Our results reveal that the residual water content after the exposure experiments increased with regolith depth, along with the organism survival rates in chlorate-containing and salt-free samples. The survival rates of the three organisms in perchlorate-containing regolith were consistently lower for all organisms and depths compared to chlorate, with the most significant difference being observed at a depth of 10-12 cm, which corresponds to the depth with the highest residual water content. The postulated reason for this is an increase in the salt concentration at this depth due to the freezing of water, showing that for these organisms, perchlorate brines are more toxic than chlorate brines under the experimental conditions. This underscores the significance of chlorate salts when considering the habitability of Martian environments.
Topics: Perchlorates; Mars; Chlorates; Extraterrestrial Environment; Aspergillus niger; Saccharomycetales; Water; Microbial Viability
PubMed: 38773211
DOI: 10.1038/s41598-024-62346-y