Species Of White-rot Fungi Research Articles

Uranium mining effluents: What about the re-use of mining wastes to improve the bioproduction of industrially relevant bioactive compounds?

The shift towards a circular economy, where waste generation is minimized through waste re-use and the development of valorization strategies, is crucial for the establishment of a low carbon, sustainable, and resource-efficient economy. However, there is a lack of strategies for re-using and valorizing specific types of waste, particularly those containing naturally occurring radioactive materials (NORM), despite the prevalence of industrial activities that produce such waste due to their chemical and radiological hazards.Living organisms, including fungi, are valuable sources of bioactive compounds with various industrial applications. In this study, we assessed the growth and metabolic profile changes of three white rot fungi species in response to low concentrations of a uranium mine effluent containing NORM and metals to explore their potential for producing biotechnologically relevant bioactive compounds. The growth rate was assessed in three different culture media, with and without the uranium mine effluent (1% V/V)), and the metabolic profile was analyzed using FTIR-ATR spectroscopy.Results suggested an improvement in growth rates in media containing the uranium mine effluent, although not statistically significant. T. versicolor showed promise in terms of bioactive compound production. The production of droplets during growth experiments and significant metabolic changes, associated with the production of bioactive compounds like laccase, melanin, and oxalic acid, were observed in T. versicolor grown in mYEPDA with the uranium mine effluent. These findings present new research opportunities for utilizing waste to enhance the biotechnological production of industrially relevant bioactive compounds and promote the development of circular economy strategies for re-using and valorizing NORM-containing waste.

By the force of decay: A green strategy to fabricate white rot fungal degraded wood for sustainable oil/water separation

Two species of white rot fungi, Coriolus versicolor（Cv）and Fomes fomentarius (Ff), were successfully applied to selectively degrade lignin of balsa wood, which caused weight loss of 15.66% and 9.66% respectively. Subsequently, the remained wood template was impregnated with 1 wt% cuprous oxide modified phenol formaldehyde resin and 4.8 wt% Stearic acid (STA, C17H35COOH), which was endowed with superhydrophobicity, high oil absorption capacity and filtration efficiency up to 8.97 g/g and 95% respectively. It was first time discovered that the absorption capacity of as prepared wood was not decreased but improved with the increase of the recycle times. Characterized by absorption efficiency of chloroform increased from the initial 5.69–8.97 g/g after 84 times repeat oil absorption process. While, the filtration efficiency for chloroform remains above 95% even after 84 cycles. Furthermore, the as modified balsa wood performed desirable photocatalytic degradation efficiency toward methylene blue (MB) more than 95% even after 84 cycles, this multifunctional aspect enhances the material's applicability for various environmental remediation purposes. This work proposed a novel, green and facile strategy to fabricate sustainable oil/water separation material, which has potential to be applied to oil/water separation industry.

Biotechnological Processing of Sugarcane Bagasse through Solid-State Fermentation with White Rot Fungi into Nutritionally Rich and Digestible Ruminant Feed

Sugarcane (Saccharum officinarum) bagasse (SCB) is one of the most widely produced lignocellulosic biomasses and has great potential to be recycled for sustainable food production as ruminant animal feed. However, due to severe lignification, i.e., lignin-(hemi)-cellulose complexes, ruminants can only ferment a minor fraction of the polysaccharides trapped in such recalcitrant lignocellulosic biomasses. This study was therefore designed to systematically evaluate the improvement in nutritional value, the in vitro dry matter digestibility (IVDMD), and the rate and extent of in vitro total gas (IVGP) and methane (CH4) production during the 72 h in vitro ruminal fermentation of SCB, bioprocessed with Agaricus bisporus, Pleurotus djamor, Calocybe indica and Pleurotus ostreatus under solid-state fermentation (SSF) for 0, 21 and 56 days. The contents of neutral detergent fiber, lignin, hemicellulose and CH4 production (% of IVGP) decreased (p < 0.05), whereas crude protein (CP), IVDMD and total IVGP increased (p < 0.05) after the treatment of SCB for 21 and 56 days with all white-rot fungi (WRF) species. The greatest (p < 0.05) improvement in CP (104.1%), IVDMD (38.8%) and IVGP (49.24%) and the greatest (p < 0.05) reduction in lignin (49.3%) and CH4 (23.2%) fractions in total IVGP were recorded for SCB treated with C. indica for 56 days. Notably, C. indica degraded more than (p < 0.05) lignin and caused greater (p < 0.05) improvement in IVDMD than those recorded for other WRF species after 56 days. The increase in IVGP was strongly associated with lignin degradation (R2 = 0.72) and a decrease in the lignin-to-cellulose ratio (R2 = 0.95) during the bioprocessing of SCB. Our results demonstrated that treatment of SCB with (selective) lignin-degrading WRF can improve the nutritional value and digestibility of SCB, and C. indica presents excellent prospects for the rapid, selective and more extensive degradation of lignin and, as such, for the improvement in nutritional value and digestibility of SCB for ruminant nutrition.

Selection of White-Rot Fungi for Decolorization of Palm Oil Mill Effluent and Evaluation of Biodegradation and Biosorption Processes

Ten species of white-rot fungi were evaluated for their ability to decolorization of palm oil mill effluent. The highest decolorization efficiency was found with Trametes elegans (PP17-06), followed by Ganoderma sp.2 (PW17-06) and Ganoderma sp.2 (PW17-177), respectively. T. elegans was further evaluated for the long-term performance of decolorization for 24 d. The optimal retention time for the decolorization was 8 d, with a color removal efficiency of 47.7%. Beyond 18 d of incubation, decolorization efficiency was reduced due to the autolysis of enzymes. During the biodegradation process, manganese peroxidase enzyme activities reached a maximum of 36.03 U.L−1. However, no significant laccase and lignin peroxidase activities were observed. T. elegans was also assessed for decolorization performance through biosorption on mycelial biomass. The synthesis of the enzyme was prevented by exposing the mycelium to HgCl2. Within an optimal contact time of 2 d, decolorization efficiency reached 12.5% with ADMI reduction from 4259.0 (±20.1) ADMI to 3727 (±104.04) ADMI. Results indicate that the adsorption capacity was reached at this time, and no significant color removal can be achieved by biomass. Results obtained in this study showed the potential of T. elegans in decolorizing palm oil mill effluent.

In silico analysis of the expression profile of AA9 Lytic Polysaccharide Monooxygenases (LPMOs) and the CDH Cellobiose Dehydrogenase enzyme in wood-degrader Agaricomycetes. The Pleurotus ostreatus case

Lignocellulose, the Earth’s most abundant biopolymer, is degraded by wood-decaying fungi, specifically white rot fungi (WRF) and brown rot fungi (BRF), which use different strategies. This study examines the expression profiles of the AA9 and CDH enzymes of three WRF species (Heterobasidion annosum, Phanerochaete chrysosporium, and Pleurotus ostreatus) and two BRF species (Fomitopsis pinicola and Rhodonia placenta) from the Agaricomycetes class, grown on poplar wood or glucose as the sole carbon source. Mycelia were collected between days 10 and 12, revealing distinct lignocellulose degradation strategies between WRF and BRF, evidenced by the upregulation of AA9 LPMO (lytic polysaccharide monooxygenases) and AA3_1 (Cellobiose Dehydrogenase) genes, with the co-occurrence of both types of transcripts at the time of mycelial collection. The genome analysis showed variability in the number of AA9LPMO genes between WRF and BRF, which were differentially regulated depending on the carbon source. WRF exhibited a significant upregulation of AA9 LPMO genes,. In Phanerochaete chrysosporium, only one AA9LPMO gene was homologous to Pleurotus ostreatus, which had the highest number of AA9LPMO genes among the WRF studied. Some AA9 LPMO genes in Pleurotus ostreatus were associated to transposable elements (TEs, mainly footprints of LTRs) and grouped in clustered. LTRs were found either in the flanking or within the gene coding regions with no effect on gene transcription. In silico analysis of the AA9LPMO proteins in WRF uncovered distinct features at their C-terminal ends. Most of them lacked an appended module, but those with a CBM1 were highly induced in poplar wood media. The proportion of AA9 proteins with a CBM1 module was similar in Phanerochaete chrysosporium and Heterobasidion irregulare, but lower in Pleurotus ostreatus, which contained more AA9LPMO genes overall. In Pleurotus ostreatus, AA9LPMO proteins were grouped into three clades based on their C oxidizing type, with each clade containing proteins with specific features. The abundance (redundancy) of AA9LPMO genes in WRF especially associated to footprints LTRs in Pleurotus ostreatus suggests these genes may have other roles beyond lignocellulose degradation.

Various species of Basidiomycota fungi reveal different abilities to degrade pharmaceuticals and also different pathways of degradation

The presence of pharmaceuticals (PhACs) in the aquatic environment is an emerging problem worldwide. PhACs reach surface water via the effluents of wastewater treatment plants (WWTPs). WWTPs, although able to remove organic pollutants, do not always remove PhACs. Currently, in the treatment of sewage with the activated sludge method, numerous microorganisms are used, mostly bacteria. Nevertheless, these microorganisms are not resistant to many drug contaminants, and some may also pose a risk to human health. White-rot fungi (WRF), which degrade a wide spectrum of environmental pollutants, may be used as an alternative to microorganisms. However, little data exists comparing the removal of various PhACs by different WRF. In this study, we aimed to determine the ability of three WRF Basidiomycota species, Armillaria mellea, Phanerochaete chrysosporium, and Pleurotus ostreatus, to remove PhACs from various therapeutic groups over the course of 1 h–4 days. Additionally, we identified the fungal metabolites of PhACs, proposed the degradation pathways, and assessed the toxicity of the post-culture media.All selected WRF removed PhACs, but the degree of removal depended on WRF species and PhACs type. Antidepressants and immunosuppressants were removed most efficiently by P. ostreatus, cardiovascular drugs and sulfamethoxazole by A. mellea, and erythromycin by P. chrysosporium. The vast differences observed highlight the need for more intensive testing of different WRF species to select the best species for removing pharmaceuticals of interest. The structure of metabolites generated during degradation strongly depended on WRF species, but the most frequent xenobiotic transformations were oxidation and dealkylation. The obtained results gave insight into the substrate specificity of selected WRF while also providing a broad extension of the knowledge of pharmaceutical degradation by A. mellea.

The relationship between tree species and wood colonising fungi and fungal interactions influences wood degradation

Deadwood is one of the main terrestrial carbon (C) pools and its decomposition is fundamental in biogeochemical cycles. As fungi are the main wood degraders, a study was carried out on deadwood-colonising fungal community changes as a function of host plants and wood degradation. Deadwood fungal communities were investigated in adjacent woody plantations of hybrid poplar, willow and black locust established in the early 2000 s and abandoned for fifteen years. Lying deadwood was estimated in the three plantations and wood decay (WD) visually assessed using a 3-class scale. Fungal colonization of wood samples was assessed using culture-based methods and identified with morphological and molecular features. Wood colonising fungal communities differed in composition both between host plants and WD classes (P < 0.001). Ligninolytic white rot fungal species (Basidiomycota) prevailed in black locust and poplar, where they co-colonised all three wood decay classes in association with soft rot fungal agents. In willow, Daldinia chilidiae, a ligninolytic ascomycete, co-colonised deadwood with fungal species associated with tree dieback (Botryosphaeriaceae); whilst soft rot fungi principally colonised the highest wood degradation class. Results showed high fungal preference towards tree species that was most evident in ligninolytic fungi. Moreover, different wood decay paths were deduced from fungal changes across the three wood degrading classes and the necromass distribution in those classes. The co-habitation of white rot and soft rot fungi in all the wood decay classes of poplar and black locust indicated a continuum decay process; whilst the prevalence of soft rot fungi in the almost decomposed class in willow, suggested sequential succession of primary and secondary phases in deadwood degradation. Wood degradation is influenced by plant species and the native fungal microbiome and is mediated by multiple biotic interactions and environmental factors, which supports the use of wood colonising fungi as indicators of forest ecosystem health.

Bioremediation of the synthetic musk compounds Galaxolide and Tonalide by white rot fungal strain-assisted phytoremediation in biosolid-amended soil

The study was aimed to conduct the bioremediation of synthetic musks by four species of white rot fungi combined with phytoremediation (Zea mays) in biosolid-amended soils where only Galaxolide (HHCB) and Tonalide (AHTN) were found as other musks were below the detection limit (0.5–2 μg/kg dw). The HHCB and AHTN concentration in natural attenuation treated soil was decreased by not more than 9%. In solely mycoremediation, Pleurotus ostreatus was found to be the most efficient fungal strain, with the higher (P < 0.05) HHCB and AHTN removal (51.3% and 46.4%). Phytoremediation-only of biosolid-amended soil was also able to remove HHCB and AHTN from soil significantly (P < 0.05) in comparison to the control treatment without plants which resulted in the final concentration for both compounds of 56.2 and 15.3 μg/kg dw, respectively. Using white rot fungus-assisted phytoremediation, only P. ostreatus decreased the HHCB content in soil significantly (P < 0.05) by 44.7%, when compared to the initial concentration. While using Phanerochaete chrysosporium, the AHTN concentration was decreased by 34.5%, which was a significantly lower concentration at the end of experiment compared to the initial value. Via fungus-assisted phytoremediation, the enzymatic activity and fungal biomass were increased, probably due to the presence of roots in association with the soil microbiome, in the process increasing the degradation of fragrances accordingly. This could lead to a higher (P < 0.05) AHTN removal in P. chrysosporium assisted phytoremediation. Estimated HHCB and AHTN bioaccumulation factors in maize were lower than 1, therefore no environmental risk would be posed.

Insights into characteristics of white rot fungus during environmental plastics adhesion and degradation mechanism of plastics

Since the 1980s, plastic waste in the environment has been accumulating, and little is known about fungi biodegradation, especially in dry environments. Therefore, the research on plastic degradation technology is urgent. In this study, we demonstrated that Phanerochaete chrysosporium (P. chrysposporium), a typical species of white rot fungi, could react as a highly efficient biodegrader of polylactic acid (PLA), and 34.35 % of PLA degradation was obtained during 35-day incubation. A similar mass loss of 19.71 % could be achieved for polystyrene (PS) degradation. Here, we presented the visualization of the plastic deterioration process and their negative reciprocal on cell development, which may be caused by the challenge of using PS as a substrate. The RNA-seq analysis indicated that adaptations in energy metabolism and cellular defense were downregulated in the PS group, while lipid synthesis was upregulated in the PLA-treated group. Possible differentially expressed genes (DEG) of plastic degradation, such as hydrophobic proteins, lignin peroxidase (LiP), manganese peroxidase (MnP) and laccase (Lac), Cytochrome P450 (CYP450), and genes involved in styrene or benzoic acid degradation pathways have been recorded, and we proposed a PS degradation pathway.

Specific study examining silver nanoparticle-induced adaptable physiological signal changes in Phanerochaete chrysosporium in a tetracycline hydrochloride-abundant system

Numerous studies have documented the toxicity of AgNPs to cells; however, few studies have attempted to explore the intrinsic mechanistic relationships between fungal cells and contaminants, particularly in the context of changes in physiological signaling in the presence of AgNPs. Therefore, we investigated the response of the model white-rot fungal species Phanerochaete chrysosporium (P. chrysosporium) to different concentrations of AgNPs in a tetracycline hydrochloride environment. The results revealed that tetracycline hydrochloride (TCH) enhanced the detoxification of P. chrysosporium at low concentrations of silver nanoparticles (AgNPs). In the TCH-abundant system, a relatively low concentration (1.0 μM) of AgNPs activated the antioxidant stress response of P. chrysosporium, enhanced the expression of H+-ATPase, K+-ATPase, and Ca2+-ATPase, increased the flow of cellular mobility signals (H+, K+, Ca2+, and O2 fluxes), and elevated cellular activity for detoxification. Higher concentrations (50.0 μM) of AgNPs inhibited cellular responses in regard to ATPase activity and mobile signals and induced high levels of reactive oxygen species (ROS), ultimately leading to cell death. The effect of AgNPs on P. chrysosporium genes in the TCH-abundant system was also investigated, and significant expression of genes related to transmembrane transport, stress response, and substance and energy metabolism was observed. This study examining the adaptive physiological response of P. chrysosporium to AgNPs in an antibiotic environment provides a new understanding of the intrinsic interaction between this fungus and contaminants.

Depolymerization of lignin by extracellular activity of Pycnoporus cinnabarinus, to obtain cellulose

Abstract Cellulose can be used to produce biofuels and many other products like pharmaceutical goods, food supplements, cosmetics, bio-plastics, etc. Lignocellulosic materials, like O. ficus indica residuals, are a heterogeneous biopolymer formed mainly by lignin, hemicellulose and cellulose. Lignin provides protection to the plants against chemical and microbial degradation, but it can be degraded by white rot fungi species, like Pycnoporus cinnabarinus. Since cellulose molecules are arranged in regular bundles enveloped by hemicellulose and lignin molecules, it is necessary to brake lignin and hemicellulose molecules to recover cellulose for its use in bioprocess. In this work, a biotechnological process for cellulose recovery from cactus waste through depolymerization of lignin by P. cinnabarinus, is presented. The delignification is carried out by aerobic culture in batch stirred bioreactors, with a liquid culture medium enriched with nutrients and minerals with O. ficus indica residuals as the unique carbon source, during eight-day span under continuous feeding of oxygen. A factorial design of experiments (DOE) for eight sets of factor values was selected for this study. The factors were: particle size, pH level, and process temperature. For each experiment, biomass, total reducing carbohydrates (TRC) and dissolved oxygen (DO) concentrations were measured every 24 h. At the end of each experiment, the percentage of delignification, and cellulose recovery was measured by Infrared (IR) spectroscopy. Up to 67% of delignification and 22% of cellulose recovery were obtained by the process. These results were analyzed by a factorial DOE in order to maximize each response individually and to optimize both responses together. The delignification of Opuntia ficus indica thorns has not been previously reported to our knowledge.

Effects of Solid-State Fermentation Pretreatment with Single or Dual Culture White Rot Fungi on White Tea Residue Nutrients and In Vitro Rumen Fermentation Parameters

Fermentation of agricultural by-products by white rot fungi is a research hotspot in the development of ruminant feed resources. The aim of this study was to investigate the potential of the nutritional value and rumen fermentation properties of white tea residue fermented at different times, using single and dual culture white rot fungal species. Phanerochaete chrysosporium, Pleurotus ostreatus, and Phanerochaete chrysosporium + Pleurotus ostreatus (dual culture) solid-state fermented white tea residue was used for 4 weeks, respectively. The crude protein content increased significantly in all treatment groups after 4 weeks. Total extractable tannin content was significantly decreased in all treatment groups (p &lt; 0.01). P. chrysosporium and dual culture significantly reduced lignin content at 1 week. The content of NH3-N increased in each treatment group (p &lt; 0.05). P. chrysosporium treatment can reduce the ratio of acetic to propionic and improve digestibility. Solid state fermentation of white tea residue for 1 week using P. chrysosporium was the most desirable.

Valorisation Potential of Invasive Acacia dealbata, A. longifolia and A. melanoxylon from Land Clearings.

Acacia spp. are invasive in Southern Europe, and their high propagation rates produce excessive biomass, exacerbating wildfire risk. However, lignocellulosic biomass from Acacia spp. may be utilised for diverse biorefinery applications. In this study, attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR), high-performance anion-exchange chromatography pulsed amperometric detection (HPAEC-PAD) and lignin content determinations were used for a comparative compositional characterisation of A. dealbata, A. longifolia and A. melanoxylon. Additionally, biomass was treated with three white-rot fungi species (Ganoderma lucidum, Pleurotus ostreatus and Trametes versicolor), which preferentially degrade lignin. Our results showed that the pre-treatments do not significantly alter neutral sugar composition while reducing lignin content. Sugar release from enzymatic saccharification was enhanced, in some cases possibly due to a synergy between white-rot fungi and mild alkali pretreatments. For example, in A. dealbata stems treated with alkali and P. ostreatus, saccharification yield was 702.3 nmol mg−1, which is higher than the samples treated only with alkali (608.1 nmol mg−1), and 2.9-fold higher than the non-pretreated controls (243.9 nmol mg−1). By characterising biomass and pretreatments, generated data creates value for unused biomass resources, contributing to the implementation of sustainable biorefining systems. In due course, the generated value will lead to economic incentives for landowners to cut back invasive Acacia spp. more frequently, thus reducing excess biomass, which exacerbates wildfire risk.

Investigation of neomycin biodegradation conditions using ericoid mycorrhizal and white rot fungal species

BackgroundIn the search for methods to biodegrade recalcitrant compounds, the use of saprotrophic fungi and white rot fungi, in particular belonging to the phylum Basidiomycota, has gained interest. This group of fungi possesses a battery of unspecific extracellular enzymes that can be utilized in the biodegradation of preferably phenolic compounds. In this work, it was investigated under which conditions the white rot fungus Trametes versicolor and the ericoid mycorrhizal fungus Rhizoscyphus ericae (belonging to the phylum Ascomycota) could be used to biodegrade the antibiotic aminoglycoside neomycin at co-metabolic conditions in which external nutrients were supplied. Furthermore, it was also investigated whether a biodegradation could be accomplished using neomycin as the sole nutrient.ResultsThe results show that both species can biodegrade neomycin 70% under co-metabolic conditions during a one-week time course and that Rhizoscyphus ericae is able to use neomycin as sole nutrient and to approximatively biodegrade it 60% under chosen non co-metabolic conditions.At selected conditions, the biodegradation of neomycin using Rhizoscyphus ericae was monitored by oxidation products of D-ribose which is a hydrolysis product of neomycin.ConclusionThe results are of general interest in the search for fungal species that can biodegrade recalcitrant compounds without the need of external nutrients. The key future application area that will be investigated is purification of waste from recombinant protein production in which neomycin, nutrients and E. coli with neomycin resistance genes are present.

Interactions between biofiller-modified polymeric composites and wood-rotting fungi in terms of their biotechnological applications

The synthesis and characterization of polymeric cross-linked composites derived from bisphenol A glycerolate diacrylate (BPA.GDA) and N-vinyl-2–2pyrrolidone (NVP) are presented. Commercially available kraft lignin with different weight % (0, 5, and 20) was applied as an environmentally friendly filler. The composites were made by bulk polymerization using a photoinitiator (2-dimethoxy-2-phenylacetophenone) in special glass molds and cut into 10 mm × 10 mm fragments for testing. The chemical structures of the composites were confirmed by means of ATR-FTIR spectroscopy. Polymers modified with the addition of lignin were introduced into cultures of three species of white rot fungi: Cerrena unicolor, Pycnoporus sanquineus, and Abortiporus biennis. The biochemical and profilometric analyses showed clear changes both in the course of selected metabolic processes in the fungal cells and in the structure of the biomaterials. Clear changes in the activity of such enzymes as laccase, β-glucosidase, or acid proteases caused by the selected polymers were observed in the culture fluids.

Laccase activities from three white-rot fungal species isolated from their native habitat in North China using solid-state fermentation with lignocellulosic biomass

Laccase has huge potential application in all aspects of biotechnology due to the ability of laccase to oxidize a wide range of phenolic and non-phenolic compounds. The future success of such applications requires large amounts of laccase with low costs. White-rot fungi are important groups of laccase production. In this study, three white-rot fungi, Phlebia acerina Han 618, Trametes hirsuta Han 726, and Coriolopsis trogii Han 751, isolated from a native North China habitat, were identified by the method of molecular biology and preliminary screening of the ability of laccase-production by guaiacol selection medium. Then they were fermented on different lignocellulosic biomass. Three species showed consistency in preference of lignocellulosic biomass, and the presence of stalk of Sorghum bicolor was more suitable for secreting laccase. The capacity of laccase secretion from different species was significantly different. The capacity of secreting laccase of C. trogii Han 751 was superior to that of P. acerina Han 618 and T. hirsuta Han 726. The discovery of a new strain with superior capacity of secreting laccase and suitable lignocellulosic biomass were helpful for laying a foundation for the optimization of the fermentation conditions for the highest laccase production, the isolation and purification of laccase, and the industrial application of laccase.

Combining biodelignification and hydrothermal pretreatment of oil palm empty fruit bunches (OPEFB) for monomeric sugar production

Oil palm empty fruit bunches (OPEFB) is the most abundant agro-industrial waste in Indonesia. It has 22.03–35% hemicellulose content. This paper reports the delignification of OPEFB using white-rot fungi followed by hydrothermal pretreatment to enhance the xylose and glucose production. The study was conducted by comparing the performance of two different species of white-rot fungi (Marasmius sp. and Phanerochaeta chrysosporium) in OPEFB mass loss, the ability to degrade lignin and hydrolyze OPEFB that had been treated enzymatically at various cultivation times. Marasmius sp. (26.67%) achieved the best lignin degradation ability during 20 days of cultivation. The best xylose recovery (166 mg/g OPEFB) and glucose recovery (283 g/g OPEFB) occurred at bio-delignification using Marasmius sp. for 30 days, followed by hydrothermal pretreatment for 15 min at a temperature of 160 °C. The combination of these two pretreatments increased monomeric sugar yield over the length of cultivation time.

Dietary supplementation with Ceriporia lacerata improves learning and memory in a scopolamine-induced amnesia mouse model.

The online version contains supplementary material available at 10.1007/s10068-021-00945-5.

How temperature variation affects white-rot fungi mycelial growth dynamics: a nonlinear mixed models approach

This study aimed to model mycelial growth in a factorial experiment with two species of white rot fungi growing at five temperatures. The nonlinear models evaluated were logistic, Gompertz, Weibull and von Bertalanffy. The adjustments were performed first by evaluating the fixed and mixed-effects models with random effects, added to the fixed parameters. Then, the best adjusted model was improved by an adequated covariance structure, and dummy variables were added to the parameters asymptote (α) and abscissa of the inflection point (β) in the model in order to verify the effect of the experiment factors, species and temperatures on the regression parameters. The criteria used to compare models were residual variance and Akaike information criterion. Gompertz and von Bertalanffy mixed-effects models were better adjusted. The parameters differed between species. Moreover, the linear and quadratic effects of temperature evaluated in each species were significant. The models were reparametrized in order to consider two parameters of interest: velocity (μ) at the inflection point and lag time (λ). The maximum growth velocity was obtained at 25.4 °C by S. ostrea, while T. villosa was achieved at 30.5 °C; both fungi suffered less lag time by increasing the temperature.

The white-rot fungus, Phanerochaete chrysosporium, under combinatorial stress produces variable oil profiles following analysis of secondary metabolites.

The effects of combinatorial stress on lipid production in Phanerochaete chrysosporium remain understudied. This species of white-rot fungi was cultivated on solid-state media while under variable levels of known abiotic and biotic stressors to establish the effect upon fungal oil profiles. Environmental stressors induced upon the fungus included the following: temperature, nutrient limitation and interspecies competition to assess impact upon oil profiles. Fatty acid type and its concentration were determined using analytical methods of gas chromatography and mass spectrometry. Growth rate under stress was established using high-performance liquid chromatography with ergosterol as the biomarker. Fungi grown on solid-state agar were able to simultaneously produce short- and long-chain fatty acids which appeared to be influenced by nutritional composition as well as temperature. Addition of nitrogen supplements increased the growth rate, but lipid dynamics remained unchanged. Introducing competition-induced stress had significantly altered the production of certain fatty acids beyond that of the monoculture while under nutrient-limiting conditions. Linoleic acid concentrations, for example, increased from an average of 885ngμl-1 at monoculture towards 13820ngμl-1 at co-culture, following 7days of incubation. Interspecies competition produced the most notable impact on lipid production for solid-state media cultivated fungi while the addition of nitrogen supplementation presented growth and lipid accumulation to be uncorrelated. Combinatorial stress therefore influences the yield of overall lipid production as well as the number of intermediate fatty acids produced, deriving similar oil profiles to the composition of vegetable and fish oils. Fungal secondary metabolism remains highly sensitive following combinatorial stress. The outcome impacts the research towards optimizing fungal oil profiles for biomass and nutrition. Future investigations on fungal stress tolerance mechanisms need to address these environmental factors throughout the experimental design.