Mycelium Of Aspergillus Niger Research Articles

Sustainable wood composite production using cotton waste and exopolysaccharides as green binders

Burning agricultural waste is a common practice among farmers in many countries, leading to global warming and climate change. Upcycling abundant agricultural waste will prevent incineration-generated hazards and provide sustainable and eco-friendly wood. An alternative wood composite was prepared using Aspergillus niger mycelium and exopolysaccharides (EPS) as a green binder. Autoclaving and gamma irradiation were both tested as wood pre-treatment to enhance binding. The mixture was incubated at 30 °C for 1 week. The results showed that wet pre-treatment using autoclaving resulted in improved wood binding compared to dry gamma irradiation treatment. The results show that the composite with the lowest water absorption was autoclaved before inoculation with 25 % EPS-induced Aspergillus niger, its tensile strength was 2.01 MPa and Modulus of elasticity of 1240.42 MPa and water resistance duration of 72 h. The biodegradation rate was 21.5 % for linseed oil-coated composite compared to 15.63 % for non-coated wood after 6 weeks. The samples demonstrated thermal conductivity as low as 0.06025 W/mK and linear Ohmic behavior within the investigated voltage range, rendering it a competitive insulating material. In conclusion, autoclaving and inoculum size play a key role in binding cotton wood waste. The key results render the optimized composite suitable for industrial applications due to its affordability, green manufacturing process, and potential for large-scale production.

Propolis extract and Hermetia illucens larval proteins synergistically inhibit the growth of Aspergillus niger

The individual and combined inhibitory activities of propolis extract (PE) and Hermetia illucens larval proteins (Black soldier fly larvae proteins) (BSFLP) against Aspergillus niger were investigated. The antifungal effects of PE, BSFLP and Synergy of PE and BSFLP (SPB) against Aspergillus niger were determined by mycelial growth, spore germination rate and hyphal elongation. Membrane integrity was measured by assessing changes in extracellular proteins, reducing sugars, and electrical conductivity. Intracellular MDA, H2O2, ergosterol, and mannan contents were also evaluated. SEM was used to observe the morphology of the Aspergillus niger mycelium. Additionally, AutoDock Tools software and multi-ligand docking methods were used to study the synergistic interactions of ligand combinations on the receptor. The results showed that the combination of PE and BSFLP had excellent effects. During the treatment of antifungal agents, the membrane permeability changed and a large amount of content leaked, while control check (CK) remained almost unchanged. Ergosterol content was found to increase, while mannan content decreased significantly, leading to cell death. In addition, SPB can cause abnormal accumulation of MDA and H2O2, leading to oxidative stress in cells. SEM results showed that morphology of Aspergillus niger treated with SPB was severe wrinkling, distortion and even breakage. Multi-ligand docking results showed that the binding affinity of receptor 1KS5 to 14 complex ligands increased, as indicated by the decrease in docking energy values. These results provide scientific basis for further study on the application of SPB and development of effective antifungal products.

Induction of Antioxidant Activity by Selenium Compounds in the Aspergillus niger Mycelium

Induction of Antioxidant Activity by Selenium Compounds in the Aspergillus niger Mycelium

Three-dimensional porous Na4MnV(PO4)3 constructed by Aspergillus niger biological template as a high performance cathode for sodium ion batteries

The sodium super ion conductor (NASICON) structure materials have attracted extensive attention because of its open three-dimensional crystal network framework and fast sodium ion migration rate. However, the poor electronic conductivity due to the presence of phosphate groups and the consequent high cost have been a barrier to commercialization. In this work, Na4MnV(PO4)3 (NMVP) with three-dimensional porous structure is synthesized in situ using Aspergillus niger as a biological template (noted as NMVP/ANDC). The cell wall of Aspergillus niger is rich in hydroxyl groups, which can adsorb metal ions well, so that NMVP particles can be synthesized on Aspergillus niger without stacking and agglomeration. NMVP grows along Aspergillus niger mycelium has a spongy-like three-dimensional porous network structure, which helps the contact between active materials and electrolyte, reduces the migration distance of sodium ions, and improves the conductivity of active materials. Therefore, NMVP/ANDC has good rate performance and cycle stability. It can provide 109 mAh g−1 at 0.5 C and 79.6% capacity retention after 3000 cycles at 5 C. The biological template method is proposed in this paper opens up a simple way for the preparation of other three-dimensional porous network structural materials.

Solid State Fermentation of Olive Leaves as a Promising Technology to Obtain Hydroxytyrosol and Elenolic Acid Derivatives Enriched Extracts.

Extraction of valuable bioactive compounds from olive leaves is a hot topic and the use of sustainable and green technologies is mandatory in terms of circular economy. In this way, the use of fermentation technologies showed very interesting results in terms of phenolic compound recovery. Because of that in this work the use of solid state fermentations, as valuable tool to improve the phenolic extraction has been checked. Aspergillus oryzae (in mycelium and spore form), Aspergillus awamori and Aspergillus niger were used as fermentation microrganisms. Phenolic compounds were determined by HPLC-ESI-TOF-MS and, to our knowledge, new compounds have been tentatively identified in olive leaves. Fermentation using mycelium of Aspergillus awamori, Aspergillus niger and Aspergillus oryzae were effective to increase both hydroxytyrosol and elenolic acid derivatives whereas the use of spores of Aspergillus oryzae caused a loss of hydroxytyrosoyl derivatives, contrary the content of elenolic derivatives are comparable with the other fermentation treatments and higher than control. The proposed fermentation processes using the mycelium of Aspergillus awamori, Aspergillus niger and Aspergillus oryzae lead to an increase the hydroxytyrosyl and elenolic acid derivatives and could be used at industrial scale to obtain enriched extracts.

Submerged culture fermentation of Colletotrichum lindemuthianum DSM 12250 as biotechnological strategy for fungal chitin biotransformation

Chitin and its derived products have great potential in various industries, such as biomedical, pharmaceutical, food, among others, due to its biodegradability, biocompatibility, null toxicity, and versatility. At present, these compounds are obtained by extraction with physical, chemical, or enzymatic processes. The fungus Colletotrichum lindemuthianum DSM 12250 which produces the enzyme chitin deacetylase (ClCDA), is proposed as an alternative for the biotransformation of fungal chitin. Chitin with a % N-Acetylation of 63.6% was obtained from the dry mycelium of Aspergillus niger that, based on analysis of Fourier transform infrared spectroscopy (FT-IR) and Differential Scanning Calorimetry (DSC), is structurally similar to commercial chitin. During fermentation in submerged culture, chitin presence was not found to generate inhibition in microbial growth or the activity of the ClCDA. The maximum enzymatic activity was 0.910 ± 0.002 U/mL and deacetylation of 20.9% were achieved. This was possible due to the enzymatic machinery of the fungus that includes CDA, endo-chitinases, and N-acetyl hexosaminidases. These compounds contribute to decreasing the substrate complexity, obtaining chitosan with a DDA of 57.3%. Submerged culture fermentation of Colletotrichum lindemuthianum DSM 12250 with fungal chitin as substrate represents a potential alternative for integrating different steps in the extraction of chitin-derived products while contributing to a cleaner and more efficient production.

Fermentation Characteristics and In Vitro Digestibility of Fibers and Fiber-Rich Byproducts Used for the Feeding of Pigs.

Simple SummaryInclusion of dietary fibers into the diet may have positive impact on health and wellbeing of pigs. The objective of the study was to examine physicochemical properties of fiber preparations and fiber-rich byproducts in relation to fermentability and digestibility using in vitro batch-culture incubation. Powdered cellulose, Aspergillus niger mycelium, which is a byproduct of citric acid production, lucerne chaff, soybean shells, wheat bran, and sugar beet pulp were notably fermented and contributed to the digestible dry matter and organic matter when used as diet constituents. The tested lignocelluloses were not fermented and are rather useful as bulk materials.Dietary fibers may have positive impact on health and wellbeing of pigs. The study examined physicochemical properties of two lignocelluloses (including and excluding bark), powdered cellulose, Aspergillus niger mycelium, lucerne chaff, soybean shells, wheat bran, and sugar beet pulp in relation to fermentability and digestibility using in vitro batch-culture incubation. Maize starch and a purified cellulose were used as standardized substrates for classification of the test substrates. The substrates covered a wide range regarding their physicochemical properties. Swelling capacity (SC) was 9–411%, water binding capacity (WBC) was 4.4–14.3 g/g dry matter (DM), and water holding capacity (WHC) was 4.1–10.6 g/g DM. Gas production and other fermentation parameters—namely post-incubation pH, CH4, NH3, and short chain fatty acids (SCFA) concentrations—revealed a significant fermentation of sugar beet pulp, soybean shells, lucerne chaff, wheat bran, A. niger mycelium, and powdered cellulose, whereas the lignocelluloses were not fermented. Significant correlations were found between the physicochemical properties and the fermentation parameters (p < 0.05). Enzymatic pre-digestion mostly reduced gas, NH3, and SCFA production. In vitro digestibility of DM (IVDMD) and organic matter (IVOMD) was mostly negligible after enzymatic pre-digestion. Fermentation alone led to only 0.10–0.15 IVDMD and 0.14–0.15 IVOMD in lignocelluloses and powdered cellulose, respectively, but 0.44–0.37 IVDMD and 0.46–0.38 IVOMD in the remainder of substrates (p < 0.05). In vitro digestibility was again correlated with the physicochemical properties of the substrates and the fermentation parameters (p < 0.05). The fiber preparations and fiber-rich byproducts were fermented to a relevant extent. In contrast, lignocelluloses were not fermented and can be used rather as bulk material.

Combination of steam explosion and ionic liquid pretreatments for efficient utilization of fungal chitin from citric acid fermentation residue

Aspergillus niger mycelium residues, a citric acid fermentation by-product, is a raw material for fungal chitosan and glucosamine (GlcN). However, traditional chemical extraction of fungal chitosan and GlcN uses strong acid at high temperatures for long periods and has several drawbacks, including high cost and environmental pollution. In this work, the residues were pretreated by the combination of steam explosion (SE) and ionic liquid (IL) to produce fungal chitosan and GlcN hydrochloride. Following chemical extraction, GlcN hydrochloride yield increased by 65.49 ± 8.14%, and soluble sugar release reached 0.36–0.46 g/g via SE pretreatment at 2.5 MPa for 1 min. Fungal chitosan was produced via enzymatic hydrolysis. Combined SE and IL pretreatment increased deacetylation degree (1.29 ± 0.06-fold) of fungal chitosan by chitin deacetylase hydrolysis using Rhodococcus equi CGMCC14861 (ReCDA) at 37 °C for 6 h. Besides, fungal chitosan was produced using a by-product recycling strategy, promoting ReCDA fermentation, using supernatant with soluble sugars and proteins. After mixing 0.2 g by-product supernatant with 100 mL medium, ReCDA production was 1.5-fold higher than that in the control. This study demonstrates a green technology for efficient utilization of fungal chitin from A. niger mycelium residues of citric acid fermentation.

Synergistic antimicrobial action of phyco-synthesized silver nanoparticles and nano-fungal chitosan composites against drug resistant bacterial pathogens

Here we report the phycosynthesis of silver nanoparticles (Ag-NPs), using Codium capitatum extract, and the synthesis of fungal chitosan nanoparticles (FC-NPs), using extracted chitosan from Aspergillus niger mycelia. Then nanoconjugates from FC/Ag-NPs were produced and evaluated. The synthesized NPs had mean particles’ size diameters of 37.2, 68.4 and 79.6 nm for Ag-NPs, FC-NPs and FC/Ag-NPs, respectively. The FTIR (Fourier-transform infrared spectroscopy) analysis of synthesized NPs indicated their cross-linkage and interaction. The antibacterial activity of each type of NPs was assayed against drug resistant pathogens of Salmonella Typhimurium and Staphylococcus aureus. All NPs had powerful inhibitory effect and FC/Ag nanoconjugates had stronger activity than the other types. Scanning micrographs of FC/Ag-NPs treated S. Typhimurium elucidated vigorous alterations in cell surfaces and lethal damage to bacterial structure after 8 h of treatment. The nanoconjugates form FC-NPs and Ag-NPs had minute particle size with increasing bioactivity as antimicrobial agents to control drug resistant bacterial pathogens, which recommends their further exploration for topical applications in biomedical sectors.

Categories and biomanufacturing methods of glucosamine.

Glucosamine (GlcN) is an amine sugar, in which a hydroxyl group of glucose is replaced with an amino group. It is an important part of the polysaccharides chitin and chitosan and is highly hydrophilic. It is also an important compound required for the formation of cartilage cells and represents one of the elementary units of the cartilage matrix and joint fluid. GlcN has been widely used in food, cosmetics, health care, and pharmaceutical industries. This paper fully addresses the categories and biomanufacturing methods of GlcN, including its production by fermentation with wild-type as well as engineered microorganisms and enzymatic catalysis with a series of chitinolytic enzymes. However, GlcN is usually produced from glucose by fermentation in a coupled manner with N-acetylglucosamine (GlcNAc). Enzymatic catalysis is thus a specific pathway for production of GlcN where chitin can be directly hydrolyzed to GlcN. In industry, GlcN produced with fungal mycelium as raw materials (plant GlcN) is thought as a high-end product because of vegetarian and non-transgenosis. In our opinion, more studies should be performed in order to develop a competitive enzymatic pathway using Aspergillus niger mycelium for the preparation of high-end GlcN.

Bioactive coatings from nano-biopolymers/plant extract composites for complete protection from mycotoxigenic fungi in dates.

Contamination of date fruit with mycotoxigenic fungi is a hazardous threat. The present study investigated the effectiveness of natural derivatives for controlling this. Chitosan (Cts) was produced from Aspergillus niger mycelia and characterized and then nanochitosan (NCt) particles were synthesized from fungal Cts. Edible-coating films were formulated based on Cts, NCt, pomegranate peel extract (PPE) and their composites and these were evaluated as antifungal materials against mycotoxigenic fungi, Aspergillus flavus, Aspergillus ochraceus and Fusarium moniliforme. The Cts produced had 88.7% deacetylation, a molecular weight of 24.5 kDa and 98% solubility in diluted acetic acid, whereas the particle diameters of synthesized NCts ranged from 35 to 65 nm. The inhibition zone assay emphasized the antifungal effectiveness of the entire coating films. The most effective agent for preparing edible film was the blend of NCt + PPE followed by Cts + PPE based films. The practical application of antifungal films for date decontamination with respect to mycotoxigenic fungi demonstrates that the films were very effective for controlling the entire fungal strain and preventing growth on the fruits. The NCt + PPE and Cts + PPE based films were found to be the most effective because they could completely eliminate the growth of any fungal spore on date fruit after 48 h from the coating experiment. © 2019 Society of Chemical Industry.

Synthesis and Application of Scaffolds of Chitosan-Graphene Oxide by the Freeze-Drying Method for Tissue Regeneration.

Several biomaterials, including natural polymers, are used to increase cellular interactions as an effective way to treat bone injuries. Chitosan (CS) is one of the most studied biocompatible natural polymers. Graphene oxide (GO) is a carbon-based nanomaterial capable of imparting desired properties to the scaffolds. In the present study, CS and GO were used for scaffold preparation. CS was extracted from the mycelium of the fungus Aspergillus niger. On the other hand, GO was synthesized using an improved Hummers-Offemann method and was characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, atomic force microscopy (AFM), X-ray diffraction (XRD), and dynamic light scattering (DLS). Subsequently, three formulations (GO 0%, 0.5%, and 1%) were used to prepare the scaffolds by the freeze-drying technique. The scaffolds were characterized by FTIR, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM), to determine their thermal stability and pore size, demonstrating that their stability increased with the increase of GO amount. Finally, the scaffolds were implanted, recollected 30 days later, and studied with an optical microscope, which evidenced the recovery of the tissue architecture and excellent biocompatibility. Hence, these results strongly suggested the inherent nature of chitosan/graphene oxide (CS/GO) scaffolds for their application in bone tissue regeneration.

CHITIN- AND CHITOSAN BIOSORBENTS FROM CITRIC A CID MYCELIAL INDUSTRIAL WASTE

The goal of this study is to examine sorption capacity of chitin-glucan (ChGC) and chitosan-glucan (CsGC) biopolymer complexes extracted from the fungus Aspergillus niger mycelium. According to the findings chitosanglucan complex sorbs lead and copper ions (130–140 mg/g) better than chitin-glucan complex (50–80 ex mg/g). Langmuir theoretical model with R2= 0,996 determination coefficient well describe sorption isotherms. It is shown the chelate complex formation compound character based on ion and coordination bonds by chitin and chitosan biopolymers is more complex. According to test results the production of chitin and chitosan containing biopolymers from citric acid production mycelium by-products has a good future. The above biopolymers have a functional use. Besides of that they sorbs heavy metals and radionuclide ions.

Biodiesel fuel production by Aspergillus niger whole-cell biocatalyst in optimized medium

Methanolysis of sunflower oil catalyzed by immobilized Aspergillus niger mycelium was studied in a packed-bed reactor. The optimal cultivation parameters for A. niger were determined using full factorial and steepest ascent experimental designs. Sunflower oil, yeast extract and soybean meal were selected as the best carbon and nitrogen sources and were used in the subsequent experiments. Intracellular lipase activity and cell mass concentration were respectively 3.2 and 2.4 times greater and cultivation period decreased by 24 h compared with the initial medium. The optimum values of these most significant parameters were as follows: sunflower oil (13.2 g/L), yeast extract (6.2 g/L), soybean meal (7.4 g/L) and incubation period (72 h) at 30 °C. With A. niger biocatalyst grown in optimized conditions, the biodiesel fuel yield reached 23.1% after sixth pass of recycled reaction mixture through the reactor.

Elicitor Application Influences the Phytochemical Profile of Salacia reticulata with the Formation of New Novel Metabolites of Medicinal Value

Salacia reticulata which is a well known plant for antidiabetic properties were subject to elicitor application. The field grown plants were sprayed with aqueous extracts of 2% Aspergillus niger mycelium as biotic elicitor and 0.2mM salicylic acid as abiotic elicitor. Elicitation of phenolics and flavonoids were marginal in both the treatments. Formation of seven new compounds in biotic elicitor treatment and eight new compounds in abiotic elicitor treatment was evident from GCMS studies. Significantly Ala-Gly, Trimethylsilyl Ester; Cyclotrisiloxane, Hexamethyl and Eicosanoic Acid, 2,3-Bis[(Trimethylsilyl) Oxy] Propyl Ester were the new compounds found in both the elicitor treatments. Cyclotrisiloxane, Hexamethyl- is a known molecule with Antioxidant, Antiasthmatics and Antogonositic effects. Interestingly, Benzene acetonitrile, Alpha.-(.Beta.-D-Glucopyranosyloxy)-,(R)-, which is a potent anticancer agent and Antioxidant ,was found only upon biotic elicitor treatment. Thus this study has led to the finding of new molecules in Salacia with potent novel medicinal properties.

The potentiality of cross-linked fungal chitosan to control water contamination through bioactive filtration

Water contamination, with heavy metals and microbial pathogens, is among the most dangerous challenges that confront human health worldwide. Chitosan is a bioactive biopolymer that could be produced from fungal mycelia to be utilized in various applied fields. An attempt to apply fungal chitosan for heavy metals chelation and microbial pathogens inhibition, in contaminated water, was performed in current study. Chitosan was produced from the mycelia of Aspergillus niger, Cunninghamella elegans, Mucor rouxii and from shrimp shells, using unified production conditions. The FT-IR spectra of produced chitosans were closely comparable. M. rouxii chitosan had the highest deacetylation degree (91.3%) and the lowest molecular weight (33.2kDa). All chitosan types had potent antibacterial activities against Escherichia coli and Staphylococcus aureus; the most forceful type was C. elegans chitosan. Chitosan beads were cross-linked with glutaraldehyde (GLA) and ethylene-glycol-diglycidyl ether (EGDE); linked beads became insoluble in water, acidic and alkaline solutions and could effectively adsorb heavy metals ions, e.g. copper, lead and zinc, in aqueous solution. The bioactive filter, loaded with EGDE- A. niger chitosan beads, was able to reduce heavy metals’ concentration with >68%, and microbial load with >81%, after 6h of continuous water flow in the experimentally designed filter.

Extraction of chitosan from Aspergillus niger mycelium and synthesis of hydrogels for controlled release of betahistine

Chitosan was extracted from the fungus Aspergillus niger, an alternative source of chitin that is widely available as a byproduct of the industrial production of citric acid. Chitosan with deacetylation degree (DD) of 73.6% was characterized by elemental analysis, capillary viscometry (molecular weight of 1.9×105g/mol), Fourier transform infrared (FTIR), nuclear magnetic resonance (1H NMR, 13C NMR and 15N NMR) spectroscopies, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Fungal chitosan was crosslinked with glutaraldehyde and glutaric acid to obtain hydrogels. Chitosan hydrogels were characterized by FTIR and by scanning electron microscopy (SEM), which showed that these materials have irregular, polydisperse, and interconnected pores. Kinetic studies of the release of betahistine from the swollen hydrogels showed a Fickian diffusion mechanism. Finally, hydrolytic degradation of chitosan hydrogels under simulated physiological conditions (pH 7.4 and 37°C) was investigated as well as in vivo biocompatibility tests using New Zealand white rabbits as animal models.

Evaluation of Biocompatibility of Chitosan Films from the Mycelium of Aspergillus niger in Connective Tissue of Rattus norvegicus

Chitosan was extracted from Aspergillus niger mycelium and characterized by several techniques (FTIR, 1HNMR y 13C-CP-MAS-NMR, TGA, DSC and XRD) with a reaction yield of 5.02%, and its average viscosity molecular weight was 1.52 x 105 g/mol. Deacetylation degree was determined by elemental analysis and 1H-NMR, being around 75%. Chitosan films were obtained by film casting, using glycerol and oleic acid as plasticizers, the chitosan films were characterized by SEM and XRD. Degradability in vitro tests under physiological conditions, mechanical tests, and biocompatibility tests on Rattus norvegicus were run, followed by histological studies of connective tissue samples from the site where the films were implanted finding complete absorption of the material and no damage to nearby tissues.

Methanolysis of Sunflower Oil Using Immobilized Fungal Cells as Biocatalyst

Synthesis of biodiesel fuel by enzymatic methanolysis of vegetable oil is promising because of the indifference of such a process to the quality of the feedstock. In order to reduce costs, it is convenient to use as the catalyst immobilized cells of lipolytic microorganisms, without separation of pure lipases. We studied methanolysis of sunflower oil in a continuous flow reactor and a stirred tank reactor when using immobilized Aspergillus niger mycelium and Yarrowia lipolytica cells, both free and immobilized, as the catalyst. In the continuous flow reactor, up to 62.2% yield of fatty acid methyl esters is achieved when using Aspergillus niger cells.

Low cost aluminium foil platforms for rapid mass spectrometric differentiation of the fungal pathogen Aspergillus niger mycelium and spores by in situ gold nanosphere accelerated microwave digestion

Fungal analysis involving filamentous pathogens is usually a challenging task. The present work uses aluminium foils as MALDI MS platforms for microwave digestion of whole fungal mycelium and spores belonging to the pathogen, A. niger. The 10 mm2 aluminium foil platforms cut from a 2 USD worth 80 m commercial foil pack, costs about 0.000008 USD per platform. The home made aluminium target holder on which we mount these foils costs only 100 USD, compared to the 600 USD of conventional stainless steel MALDI MS target plates. Hence a 6-times reduction in cost has been achieved using our system. Our results and optimization experiments concluded that a 3 min microwave digestion could lead to significant signals both in the case of mycelium and spores. The signals obtained were reliable and could help in the differentiation between the non-infecting mycelium and the highly infective and contagious sporulation phase. We further used the homemade Au nanospheres, known for their high heat absorption ability, for accelerating the microwave digestion on the Al foil platforms. The fungal analyte (mycelium/spores) when sandwiched between the Al foil on the ventral side and the Au nanospheres on the dorsal side led to significant reduction in the microwave time from 3 min to 30 s.