Growth Of White-rot Fungi Research Articles

Influence of metals on lignocellulolytic enzyme production and metal removal by Phlebia brevispora in a wheat straw based fixed‐bed bioreactor

AbstractHeavy metals contamination poses a significant environmental threat, which requires the development of eco‐friendly bioremediation techniques. Present research work was conducted using wheat straw in submerged conditions for the growth of white rot fungus, Phlebia brevispora in the presence of varying concentrations of Cd, Pb, Ni, and Cr. The lignocellulolytic enzyme production ability of fungus was monitored. A wheat straw‐based fixed‐bed bioreactor was designed to treat metal‐containing water in continuous mode. The fungus showed a positive influence on laccase production, cellulase production, and lignin peroxidase activity. As observed through atomic absorption spectroscopy (AAS), Cr removal efficiency was 78%–80%, regardless of the initial metal concentration. The Cr was also found on the surface of fungal mycelium as per the results obtained from SEM–EDX. The continuous bioreactor achieved 98%–99% metal removal, making it a natural and cost‐effective solution for metal removal from wastewater using P. brevispora.

The growth of white rot fungi in the biodelignification process of sawdust of Sengon

Sengon-wood sawdust (SWD) is the waste generated from the sawmill industry and can be utilized as making ethanol and pulp because the waste contains high fiber. The material is processed through biodelignification by white rot fungi. The purpose of this study was to observe the growth of Phanerochaete chrysosporium (PC) and Trametes versicolor (TV) in the biodelignification process of wood sawdust Sengon with a single culture and mixed culture with the growth of white rot fungi macroscopic (spread of the mycelium, the color powder, texture powder) and microscopic (surface properties and thickness of mycelium) using Flat Digital Microscope and SEM (Scanning Electron Microscope). This research method used a Completely Randomized Design (CRD) with one factor: the type of white rot fungi; J1: Phanerochaete chrysosporium, J2: Trametes versicolor), J3: a mixture of PC + TV, with each 3 repetitions. The results showed that The growth of single-culture Phanerochaete chrysosporium in the process of biodelignification of sengon sawdust (SWD) is best compared to single-culture TV and co-culture PC+TV. The results of this study provide information on the selection of types of fungi that have the potential to release lignin, which facilitates the process of pulping or alcoholic fermentation for biofuels.

AKTIVITAS ANTIJAMUR PELAPUK KAYU NANOPARTIKEL KITOSAN-EKSTRAK N-HEKSAN DAGING BUAH KAYU GADIS (Cinnamomum parthenoxylon)

This study aims to synthesize chitosan nanoparticles - n-hexane extract of Cinnamomum parthenoxylon (CP) fruit using the ionic gelation method, to characterize them, and to determine their antifungal activity against the wood-rotting fungi Trametes versicolor and Fomitopsis palustris. Chitosan-CP extract nanoparticles were formulated with chitosan:Na-TPP:CP extract ratio of 1:1:0.5. Particle size and polydispersity index were determined using a particle size analyzer (PSA), and particles morphology was observed using a scanning electron microscope (SEM), and antifungal activity was measured using agar media. The results revealed that the average size of chitosan nanoparticles (base) was 276.9 nm, while the average size of chitosan-CP extract nanoparticles was 807.6 nm. The polydispersity index (PI) of both nanoparticles was greater than 0.7. Observations of the nanoparticles' morphology revealed that aggregation/agglomeration formed in the resulting particles. Both nanoparticles chitosan (base) and chitosan-CP extract inhibited the growth of white rot fungi (T. versicolor) more than brown rot fungi (F. palustris), as measured by the inhibitory zone.

Comparing carriers as a support media of white-rot fungi in natural tannins removal

• The growth of white-rot fungi was tested on polyethylene carriers containing cellulose; • Basidiomycetes could cover fully the carriers with the highest cellulose percentage; • B. adusta could grow up to 60% of carrier surface in not-sterile conditions; • B. adusta growth was associated with 25±4% Quebracho tannin sCOD removal; • B. adusta and A. tubingensis could grow together and remove Quebracho sCOD up to 15±4% In the last decades, White-rot Fungi bioremediation potential has been widely investigated, providing remarkable results toward several recalcitrant molecules. However, full-scale applications based on fungi are not employed yet and little is known about their optimal operating conditions, such as i) their ability to grow without sterile conditions, ii) co-substrate requirements and iii) the accurate carrier design for fungal growth. In this study, several batch tests were performed as preliminary steps to evaluate the possible design of a pilot-scale reactor based on fungal biomass to be operated under not-sterile conditions in the removal of Quebracho natural tannin. The tests were performed to verify fungal affinity, including Basidiomycetes and Ascomycetes for innovative cellulose-containing carriers compared to commonly employed PolyUrethane Foam Cubes. In particular, four fungi, including three Basidiomycetes White-rot Fungi, Bjerkandera adusta, Phanerochaete chrysosporium and Tyromyces chioneus and the Ascomycota strain Aspergillus tubingensis , were employed. As a first step, fungi were tested to evaluate their ability to attach and grow onto 12 types of innovative carriers made by High-Density PolyEthylene and containing cellulose in different percentages. Other tests were performed without sterile conditions. In particular, fungal abilities i) to attach and grow onto two different types of support, including cellulose-containing carrier and polyurethane foam cubes and ii) to biotransform recalcitrant molecules (Quebracho natural tannin) iii) to grow and operate synergistically in a consortium of two fungi, were evaluated. The main parameters evaluated were soluble Chemical Oxygen Demand (sCOD) reduction and dry weight increase. Basidiomycetes showed high affinity for cellulose-containing carrierswith the highest cellulose percentage (7%) achieving full colonization and 60% coverage, in sterile conditions and not- sterile conditions, respectively. These results were associated with a Quebracho sCOD removal of 25±4%, without sterility. When combined, the two selected strains, Bjerkandera adusta and Aspergillus tubingensis were able to grow on carriers and to remove up to 15±4% of tannins recalcitrant sCOD. This study provides evidence of i) Basidiomycetes high affinity for cellulose-containing carriers that could favour fungi attachment in sterile and not-sterile conditions, t .and ii) the feasibility of a combined use of Ascomycetes and Basidiomycetes in bioremediation.

Cocultivation of White-Rot Fungi and Microalgae in the Presence of Nanocellulose.

ABSTRACTCocultivation of fungi and algae can result in a mutualistic or antagonistic interaction depending on the species involved and the cultivation conditions. In this study, we investigated the growth behavior and enzymatic activity of two filamentous white-rot fungi (Trametes versicolor and Trametes pubescens) and two freshwater algae (Chlorella vulgaris and Scenedesmus vacuolatus) cocultured in the presence of TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical) oxidized cellulose nanofibrils (CNF) and cellulose nanocrystals (CNC). The growth of fungi and algae was studied in liquid, agar medium, and 3D-printed nanocellulose hydrogels. The results showed that cocultures grew faster under nutrient-rich conditions than in nutrient-depleted conditions. Key cellulose-degrading enzymes, including endoglucanase and laccase activities, were higher in liquid cocultures of T. versicolor and S. vacuolatus in the presence of cellulose compared to single cultures of fungi or algae. Although similar results were observed for cocultures of T. pubescens and C. vulgaris, laccase production diminished over time in these cultures. Fungi and algae were capable of growth in 3D-printed cellulose hydrogels. These results showed that cellulase enzyme production could be enhanced by cocultivating white-rot fungi with freshwater algae under nutrient-rich conditions with TEMPO-CNF and CNC. Additionally, the growth of white-rot fungi and freshwater algae in printed cellulose hydrogels demonstrates the potential use of fungi and algae in hydrogel systems for biotechnological applications, including biofuel production and bio-based fuel cell components.IMPORTANCE Depending on the conditions used to grow fungi and algae in the lab, they can interact in a mutually beneficial or negative way. These interactions could stimulate the organisms to produce enzymes in response to the interaction. We studied how wood decay fungi and freshwater algae grew in the presence and absence of cellulose, one of the basic building blocks of wood. How fungi and algae grew in 3D-printed cellulose hydrogels was also tested. Our results showed that fungi and algae partners produced significantly larger amounts of enzymes that degraded cellulose when grown with cellulose than when grown alone. In addition, fungi and algae were shown to grow in dense nanocellulose hydrogels and could survive the shear conditions during gel structuring while 3D-printing. These cultures could potentially be applied in the biotech industry for applications like energy production from cellulose, biofuel production, and bioremediation of cellulose material.

Rhamnolipid-assisted mycoremediation of polycyclic aromatic hydrocarbons by Trametes hirsuta coupled with enhanced ligninolytic enzyme production

ABSTRACT The present study deals with the development of a wood assisted fungal system (WAFS) from wood chips using Trametes hirsuta to remove polycyclic aromatic hydrocarbons (PAHs) in BRW. The WAFS exhibited a 1.4-fold higher ligninolytic enzyme production than free fungi in the effluent. Further, to understand PAHs bioremediation by T. hirsuta, biodegradation along with biosorption were studied in model PAHs, phenanthrene (Phe) and benzo (a) pyrene (BaP), in the presence of synthesized rhamnolipids. The WAFS mineralized up to an average of 91.26% Phe and 87.72 % BaP along with biosorption of 12.35% Phe and 18.36 % BaP within 12 days. Thus, the addition of rhamnolipids showed 1.2-fold enhanced biodegradation. However, rhamnolipid concentrations beyond 50 ppm reduced the degradation efficiency of WAFS. Moreover, the degradation capability of total aromatic hydrocarbon (TAH) in biorefinery wastewater by WAFS is 1.8-fold higher than that of free fungi, which confirms the effectiveness of the system. Implications: Simultaneous application of white-rot fungus along with surfactant into a pollutant environment affects the microenvironment of the fungus and reduces the production of their degradative enzymes. In addition, the requirement of periodical supplement of external nutrient in the real-time matrix for the growth of white rot fungi may trigger competitive growth of indigenous microorganisms. Considering this glitch, the current work utilizes the carpenter waste for the strategical develop a wood assisted fungal system to protect the microenvironment of the fungi in the presence of rhamnolipids and contribute to their survival in real time matrix, with enhanced PAHs degradation efficiency.

The remediation of chlorpyrifos-contaminated soil by immobilized white-rot fungi

This research focused on the degradation of chlorpyrifos via immobilized white rot fungi in soil, with the aim to select excellent degrading strains and an optimal carrier of white rot fungi. Immobilization of white rot fungi was assessed on corn stover, wheat straw, peanut shells, wood chip, and corn cobs. Phlebia sp., Lenzites betulinus and Irpex lacteus were grown in defined nutrient media for the remediation of pesticide-contaminated soils. The carrier of the biomass was determined by observing the growth of white rot fungi. The results showed that corn stover and wheat straw are suitable carriers of the immobilized white rot fungi and that Phlebia sp. and Lenzites betulinus have a positive effect on the degradation of chlorpyrifos. At 30?C and neutral pH, the degradation rate of chlorpyrifos was 74.35 %, Phlebia sp. being immobilized by corn stover in 7 days, which was the best result compared to other combinations of strains and carriers. The orthogonal experiment showed that the pH value and temperature affected the pollutant degradability more than the initial concentration and the biomass dosage.

Indirect Bacterial Effect Enhanced Less Recovery of Neonicotinoids by Improved Activities of White-Rot Fungus Phlebia brevispora.

Bacterial strains that improve mycelial morphology and growth of white-rot fungi in liquid medium could enhance the impact of white-rot fungi towards lesser recovery of neonicotinoids when cocultured. This was demonstrated by the recovery of clothianidin and acetamiprid from cocultures of the white-rot fungus Phlebia brevispora strains with two mycelial-growth-promoting bacteria, Enterobacter sp. TN3W-14 and Pseudomonas sp. TN3W-8. Clothianidin recovery from cocultures of white-rot fungi and bacteria was over 40% lower than that from axenic microbial cultures and mixed-bacterial cultures. About 20% less acetamiprid was equally recovered from both TMIC33929+TN3W-14 cocultures and mixedbacterial cultures than from axenic fungal and bacterial cultures.

Fungi-Enabled Synthesis of Ultrahigh-Surface-Area Porous Carbon.

The growth of white-rot fungi is related to the superior infiltrability and biodegradability of hyphae on a lignocellulosic substrate. The superior biodegradability of fungi toward plant substrates affords tailored microstructures, which benefits subsequently high efficient carbonization and chemical activation. Here, the mechanism underlying the direct growth of mushrooms toward the lignocellulosic substrate is elucidated and a fungi-enabled method for the preparation of porous carbons with ultrahigh specific surface area (3439 m2 g-1 ) is developed. Such porous carbons could have potential applications in energy storage, environment treatment, and electrocatalysis. The present study reveals a novel pore formation mechanism in root-colonizing fungi and anticipates a valuable function for fungi in developing the useful porous carbons with a high specific surface area.

Fungal treatment of humic-rich industrial wastewater: application of white rot fungi in remediation of food-processing wastewater

ABSTRACTThis paper presents the results of fungal treatment of a real industrial wastewater (WW), providing insight into the main mechanisms involved and clarifying some ambiguities and uncertainties in the previous reports. In this regard, the mycoremediation potentials of four strains of white rot fungi (WRF): Phanerochaete chrysosporium, Trametes versicolor, Pleurotus ostreatus and Pleurotus pulmonarius were tested to remove humic acids (HA) from a real humic-rich industrial treated WW of a food-processing plant. The HA removal was assessed by color measurement and size-exclusion chromatography (SEC) analysis. T. versicolor showed the best decolorization efficiency of 90% and yielded more than 45% degradation of HA, which was the highest among the tested fungal strains. The nitrogen limitation was studied and results showed that it affected the fungal extracellular laccase and manganese peroxidase (MnP) activities. The results of the SEC analysis revealed that the mechanism of HA removal by WRF involves degradation of large HA molecules to smaller molecules, conversion of HA to fulvic acid-like molecules and also biosorption of HA by fungal mycelia. The effect of HS on the growth of WRF was investigated and results showed that the inhibition or stimulation of growth differs among the fungal strains.

Biodegradation of Different Genotypes of Miscanthus by Wood Rot Fungi

Miscanthus, which is comprised of several different genotypes, is an important high-biomass crop with applications in the biofuel industry and in the formation of biocomposite materials. The overall composition of Miscanthus can be altered via degradation with wood rot fungi. The starting composition revealed that the cellulose content of Miscanthus x giganteus was higher than that in Miscanthus sacchariflorus and that the lignin contents were similar in both genotypes. Of the wood rot fungi, only Lentinus edodes appeared to have completely colonized M. sacchariflorus and showed significant degradation. In contrast, all of the brown rot fungi showed partial colonization of both Miscanthus genotypes and had little effect on the fibrous composition. Cellulose degradation by some white rot fungi increased with cellulose content whereas cellulose degradation by other fungi was independent of cellulose content. All of the white rot fungi showed similar rates of lignin degradation, except for Pleurotus ostreatus, which was higher on M. sacchariflorus. The effect of the moisture contents of Miscanthus on cellulose and lignin decomposition by Phlebiopsis gigantea SPLog6 and Coniophora puteana 11E was also investigated. These results revealed subtle differences in the growth of white rot fungi on different Miscanthus genotypes.

Growth of White Rot Fungi in Composites Produced from Urban Plastic Waste and Wood

SummaryIn the search for new biodegradable materials is found the combination of natural fibers with conventional polymeric materials or biodegradable polymers. The incorporation of natural fibers to thermoplastic polymer matrix is associated with improvement of their properties due to advantages such as the fact that the natural fibers are biodegradable and less abrasive when compared to synthetic fibers. The materials produced with conventional synthetic polymers are considered inert to immediate attack of microorganisms, as thermoplastic polymers used in this research, PP (polypropylene) and EVA (ethylene vinyl acetate). Thus, this study aims to evaluate the potential for biodegradation of wood plastic composites (WPC) obtained through the use of post‐consumer bottle caps and wood flour. The monitoring was conducted through cultivation of different species of fungi (basidiomycetes) on different substrates, being made by gravimetric analysis and visual monitoring of the composites, in order to assess that species of fungus has increased growth kinetics and its relation with different kinds of wood and then have an estimate of the potential biotic degradation of these materials. Based on results presented here, it is concluded that the Trametes villosa (TV) fungi is that best interacted with the wood contained in the composite in both species of Eucalyptus grandis (Eu) as Pinus elliottii (Pi).

Effects of different selenium levels on growth and regulation of laccase and versatile peroxidase in white-rot fungus, Pleurotus eryngii

This study was conducted to evaluate the physiological effects of different selenium (Se) levels on the growth of white-rot fungus, Pleurotus eryngii, with special reference to the regulation of ligninolytic enzymes such as laccase and versatile peroxidase. The fungus was grown in medium supplemented with 1, 10, 100, 1,000 and 10,000 μM of sodium selenite. Mycelial growth was stronger at lower Se levels, but declined significantly at higher concentrations of 1,000 and 10,000 μM, highlighting its association in mediating toxic responses. Inhibition of fungal growth was accompanied with dense and entangled hyphae taking the shape of irregular short strips. Additionally, hyphal swellings and septation were noticed which lead to a reduction in the advancement of the mycelium. Along with the inhibition of fungal biomass, the reducing sugar and protein concentrations increased to about 30.2 and 3.5 mg/ml respectively in the growth medium. Additionally, the laccase gene expression showed a twofold upregulation at higher levels of Se, although the activity of the enzyme was compromised with an inverse relationship with increased gene transcripts. The versatile peroxidase transcript showed a complete downregulation at 10,000 μM after an upregulation at lower levels of Se. We also confirmed the direct relationship of different Se levels on laccase activity of Rhus vernicifera that showed similar behavior to the fungal laccase. The results of the present study suggest that Se supplementation regulates mRNA levels of laccase and versatile peroxidase depending on exposure and may play a role in the toxicity associated with Se.

Selected Wood Properties of Prunus Africana (Hook) Grown in Kenya as Possible Reasons for its High Natural Durability

Studies were carried out on the influence of Prunus africana heartwood extractives on the growth of selected wood decay fungi. Also, wood chemical and mineral content, dimensional stability and anatomical features of P. africana were studied. Heartwood extractives were tested in 100 ppm and 500 ppm concentrations on white, brown rot, and blue stain fungi and growth inhibition was determined as a factor of time. Dimensional stability was determined by computing the swelling coefficient after the blocks were saturated with moisture. Klason lignin, Kurschner cellulose, extractive and ash contents were determined by standard procedures. Infrared analyses were performed using Perkin Elmer FTIR spectrometer. Microscopic examination was peiformed using an environmental scanning electron microscope. The results showed that the wood is dimensionally stable, and contains 12.7 % extractives, 37.6 % cellulose and 30.4 % lignin. Extractives deposited in vessels are highly soluble in dichloromethane and mainly composed of terpenes. Extractives were able to inhibit the growth of white rot fungi Coriolus versicolor, brown rot fungi Poria placenta and blue stain fungi Aureobasidium pullulans at different concentrations tested and could explain the high durability of Prunus africana wood species.

Application of Biological-Based Antifungal Agent for Controlling the Growth of Wood Decaying Fungi of Rubberwood

Rubberwood played a crucial role in industries development in Malaysia, particularly in furniture sector. Preservative of rubberwood becomes important tool in order to obtain an environmental friendly antifungal agent. Thus, biological-based control agent was an alternative way to solve this issue. This study was conducted on the bio-production of antifungal agent towards the growth of wood decaying fungi of rubberwood. Schizohpyllum commune had reported to product schizophyllan during secondary metabolites, in which could possed antimicrobial activity. Batch solvent extraction using three solvent systems was carried out. After hydrodistillation process for 48 h, the results showed that 70% (v/v) methanol-water system provided the maximal extraction yield (41.47 %) for S. commune mycelia. The extracted antifungal agent had applied on the rubberwood block to investigate its effectiveness. The result found that the concentration at 5 μg/μl could inhibit the growth of white-rot fungi, in which was similar to that observed using minimum inhibitory concentration (MIC) assay previously.

Extractable organic carbon and counts of bacteria near the lignocellulose–soil interface during the interaction of soil microbiota and white rot fungi

The biotic and abiotic net change of bioavailable carbon was measured as water extractable organic carbon (EOC) near the interface of soil and lignocellulose. The influence on EOC of growth and interaction of a white rot fungus and the indigenous soil microorganisms was studied. During decomposition of straw by Pleurotus sp. or Dichomitus squalens, EOC in straw increased from 18 to 39–83 mg g −1 . Nevertheless, only low amounts of EOC were translocated into the adjacent soil. When sterile straw was brought into contact with nonsterile soil, consumption of EOC by the soil microorganisms in the straw was higher than the EOC flux from straw into soil. During simultaneous growth of white rot fungi and soil organisms, propagation of soil bacteria in straw and growth of the fungal mycelia in soil were partially inhibited. However, the accumulation of EOC in straw by the fungi continued in the presence of soil microbiota.

Changes to water repellence of soil caused by the growth of white-rot fungi: studies using a novel microcosm system.

A microcosm system is described which permits assessment of the progressive growth of filamentous fungi through soil. We report on its application to measure the effects of Coriolus versicolor and Phanerochaete chrysosporium upon the sorptivity and water repellence of a mineral soil, measured using a miniature infiltration device. Both fungal species caused moderate sub-critical repellence. Since the pore structure was unaffected, the repellence was probably due to hydrophobic substances of fungal origin. This is the first report of changes in soil repellence caused by the growth of potential xenobiotic bioremediating fungi. The potential consequences are discussed.

Changes to water repellence of soil caused by the growth of white-rot fungi: studies using a novel microcosm system

A microcosm system is described which permits assessment of the progressive growth of filamentous fungi through soil. We report on its application to measure the effects of Coriolus versicolor and Phanerochaete chrysosporium upon the sorptivity and water repellence of a mineral soil, measured using a miniature infiltration device. Both fungal species caused moderate sub-critical repellence. Since the pore structure was unaffected, the repellence was probably due to hydrophobic substances of fungal origin. This is the first report of changes in soil repellence caused by the growth of potential xenobiotic bioremediating fungi. The potential consequences are discussed.

Hydroxyl Radical Activity Associated with the Growth of White-Rot Fungi

On a utilise une methode de chimiluminescence sensible et selective pour detecter les radicaux hydroxyles lors de la croissance des champignons de la pourriture blanche. L'etude revele que la croissance fongique est accompagnee par la generation de radicaux hydroxyles qui a leur tour apparaissent comme responsables de la phase initiale de degradation fongique du bois.

Solid substrate growth of white rot fungi on coffee pulp

AbstractThe presence of several antiphysiological factors limit the use of coffee pulp in monogastric and ruminant feeding. Twenty six white rot fungi were grown under solid substrate conditions in previously ensiled and pressed coffee pulp without adding additional sources of nitrogen. All grew and wholly covered the surface of the substrate. Six of them produced fruiting bodies. The weight loss interval ranged between 6.7–28.0% dry matter before fructification and from 17.0 to 48.7% after fructification. Some fungi biodegraded about 70, 55 and 47% of the total polyphenols, caffeine and permanganate lignin present in the original substrate.