Search

[Display omitted] • P. ostreatus mycelium biomass and EPS were optimized by GA-RSM. • Biomass (36.45 g/L) and EPS (6.72 g/L) were obtained under optimized conditions. • ANN showed better prediction performance results than RSM. • A user-friendly GUI was developed for computing mycelium biomass and EPS production. This study aimed to enhance the production of mycelium biomass and exopolysaccharides (EPS) of Pleurotus ostreatus in submerged fermentation. Response Surface Methodology (RSM) sought to optimize culture conditions, whereas Artificial Neural Network (ANN) aimed to predict the mycelium biomass and EPS. After optimization of RSM model conditions, the maximum biomass (36.45 g/L) and EPS (6.72 g/L) were obtained at the optimum temperature of 22.9 °C, pH 5.6, and agitation of 138.9 rpm. Further, the Genetic Algorithm (GA) was employed to optimize the cultivation conditions in order to maximize the mycelium biomass and EPS production. The ANN model with an optimized network structure gave the coefficient of determination (R2) value of 0.99 and the least mean squared error of 1.9 for the validation set. In the end, a graphical user interface was developed to predict mycelium biomass and EPS production. [ABSTRACT FROM AUTHOR]

[Display omitted] • WRF P. ostreatus GEMB-PO1 exhibits noteble Cu tolerance and measurable Cu removal. • Transcriptomic data reveals elevated lignocellulolytic enzyme under Cu condition. • The co-remediation by GMEB-PO1 significantly boosts organic pollutant degradation. Addressing the environmental contamination from heavy metals and organic pollutants remains a critical challenge. This study explored the resilience and removal potential of Pleurotus ostreatus GEMB-PO1 for copper. P. ostreatus GEMB-PO1 showed significant tolerance, withstanding copper concentrations up to 2 mM. Its copper removal efficiency ranged from 64.56 % at 0.5 mM to 22.90 % at 8 mM. Transcriptomic insights into its response to copper revealed a marked upregulation in xenobiotic degradation-related enzymes, such as laccase and type II peroxidases. Building on these findings, a co-remediation system using P. ostreatus GEMB-PO1 was developed to remove both copper and organic pollutants. While this approach significantly enhanced the degradation efficiency of organic contaminants, it concurrently exhibited a diminished efficacy in copper removal within the composite system. This study underscores the potential of P. ostreatus GEMB-PO1 in environmental remediation. Nevertheless, further investigation is required to optimize the simultaneous removal of organic pollutants and copper. [ABSTRACT FROM AUTHOR]

[Display omitted] • Spent Substrate of Pleurotus ostreatus can act as potential biomass for biobutanol production. • Clostridium acetobutylicum MTCC 11274 produced ABE concentration of 10.80 ± 0.02 g/L. • Hybrid pre-treatment showed maximum biobutanol yield of 0.38 g/g. • SEM, FT-IR, XRD data confirmed the breakdown of lignin and hemicellulose. Addressing global energy demand, researchers sought eco-friendly biobutanol production from lignocellulosic waste biomass. In the present research work, five different pre-treatment methods viz., Microwave, Ultrasound, Alkali, Acid, and Hybrid, were investigated to explore its biobutanol production potential by utilizing Pleurotus ostreatus spent as substrate. The compositional and physico-chemical changes of the pre-treated Spent Mushroom Substrate (SMS) were assessed using SEM, FTIR, and XRD. Hybrid pre-treatment (Microwave, Alkali, Ultrasound) showed higher delignification when compared to conventional pre-treatment method. Hybrid pre-treated SMS resulted in higher total reducing sugars (521.53 ± 1.84 mg/g) than indigenous SMS (267.89 ± 1.53 mg/g). Fermentation of hybrid pre-treated SMS with Clostridium acetobutylicum MTCC 11274 produced the highest biobutanol concentration (9.84 ± 0.03 g/L) and yielded 0.38 ± 0.02 g/g of biobutanol. This study revealed that hybrid pre-treatment could be a promising solution for enhanced biobutanol production using SMS biomass. [ABSTRACT FROM AUTHOR]

Highlights • An edible fungi-assisted harvesting system for efficient microalgae bio-flocculation was developed. • Maximum recovery efficiency of 64.86% was achieved in 150 min. • This system is suitable for flocculent-free harvesting of microalgae as feedstock for feed or food production. Abstract Conventional flocculants, commonly used to improve harvesting efficiency, can contaminate the broth and cause microalgae not suitable for food or feed production. In the present study, Pleurotus ostreatus , an edible fungal strain, was developed to improve the harvesting efficiency of microalgae. The results show that Pleurotus ostreatus pellets cultured under 100 rpm agitation resulted in higher harvesting efficiency than pellets cultured under 0 rpm and 150 rpm agitation. Lower pH of the Chlorella sp. suspension resulted in higher harvesting efficiency. The maximum recovery efficiency reached 64.86% in 150 mins. The above process could be used to achieve low cost, flocculant-free harvesting of microalgae as feedstock for feed or food production. [ABSTRACT FROM AUTHOR]

[Display omitted] • The mechanism of pretreatment effects on DG enzymatic digestibility was revealed. • Enzymatic hydrolysate of pretreated DG was used for 1,3-propanediol production. • The changes in DG starch content and properties were analyzed. • Laccase pretreatment improved xylose and arabinose conversion of DG. • The changes in components and features of fungal pretreated DG were analyzed. To minimize environmental pollution and waste of resources, distillers' grains (DG) was used to produce 1,3-propanediol. Biological, physical, and chemical methods were used for pretreatment. The correlation between features of pretreated samples and enzymatic digestibility was analyzed. The results showed that the glucan and xylan conversion of dilute sulfuric acid pretreated DG increased by 69.59% and 413.68%, respectively. The glucan conversion of microwave pretreated and xylan conversion of laccase pretreated DG increased by 14.22% and 34.19%, respectively. Pretreatment enhanced enzymatic digestibility through changing the dense structure and features of DG making them conductive to enzymatic hydrolysis. The production of 1,3-propanediol using enzymatic hydrolysate of pretreated DG and glycerol in shake-flask was 17 g/L. The utilization of DG not only provides plentiful raw materials replacing fossil fuels to produce biofuels and other chemicals but efficiently reduces environmental waste. [ABSTRACT FROM AUTHOR]

Lignocellulosic wastes are generally pre-treated to facilitate the hydrolysis stage during the anaerobic digestion process. A process consisting of solid state fermentation carried out by white rot fungi and anaerobic digestion was evaluated on corn stover to produce ligninolytic enzymes and biogas. The enzyme production was quantified every 3 d for a month at 30 °C, and three fungal strains and two particle sizes of waste were compared. Of the main outcomes, Pleurotus eryngii produced the highest laccase enzyme activity compared with Pleurotus ostreatus and Trametes versicolor . Furthermore, this activity was improved by 16% when copper was used as an enzyme inducer. On the other hand, most of the conditions studied showed a decrease in maximum biogas production compared with untreated waste, the addition of copper decreased biogas production by 20%. Despite the above, Pleurotus eryngii showed promising results allowing a 19% increase of biogas production and high enzyme production values. [ABSTRACT FROM AUTHOR]

Biocatalytic upgrading of bio-based platform chemical 5-hydroxymethylfurfural (5-HMF) to 2,5-bis(hydroxymethyl)furan (BHMF) is currently of great interest due to the product specificity, mild reaction and high efficiency. In this work, 200 mM 5-HMF could be effectively biotransformed to BHMF at 90.6% with highly 5-HMF-tolerant recombinant E. coli CCZU-K14 whole cells at pH 6.5 and 30 °C under the optimum reaction conditions (cosubstrate glucose 1.0 mol glucose/(mol 5-HMF), D -xylose 400 mM, l -glutamic acid 250 mM, Mg 2+ 1.5 mM, 0.2 mol β-cyclodextrin/(mol 5-HMF), CTAB (cetyltrimethyl ammonium bromide) 12.5 mM, and 0.1 g wet cells/mL). It was found that E. coli CCZU-K14 was highly tolerant to 5-HMF (up to 400 mM). Effective bioreduction of biomass-derived 5-HMF (≤200) to BHMF was successfully demonstrated in this study. In conclusion, this strategy showed high potential application for the synthesis of BHMF. [ABSTRACT FROM AUTHOR]

The synthesis of cellulase in filamentous fungi can be triggered by several inducers. In this study, a bamboo-shoot shell pretreated with Pleurotus ostreatus could promote the formation of cellulases in Aspergillus niger . Further identification, including UPLC-TOF-MS, ultrafiltration, and FT-IR, denoted that the soluble inducer was not a traditional disaccharide but a type of modified lignin polymer. This revelation may result in incipient strategies to ameliorate cellulase productivity. [ABSTRACT FROM AUTHOR]

• For effective FR, iron-binding to wood was maximized through pH modification. • Optimum iron dosage was identified based on maximum methane production yield. • Up to 70 % of the methane produced in the first week for pretreated samples. • FR and fungal pretreatment of SEBW increased methane yield to 420 mL/gVS. • Simultaneous FR and fungal pretreatment reduced the lignin content by up to 25%. Delignification of steam-exploded birch wood (SEBW) was stimulated using a pretreatment method including Fenton reaction (FR) and fungi. SEBW was employed as a substrate to optimize the Fe(III) and Fe(II) dosage in FR. Maximum iron-binding to SEBW was obtained at pH 3.5. FR pretreatment increased biological methane yields from 257 mL/g vS in control to 383 and 352 mL/ g vS in samples with 0.5 mM Fe(II) and 1.0 mM Fe(III), respectively. Further enzymatic pretreatment using a commercial cellulase cocktail clearly improved methane production rate but only increased the final methane yields by 2–9 %. Finally, pretreatments with the fungi Pleurotus ostreatus (PO) and Lentinula edodes (LE), alone or in combination with FR, were carried out. SEBW pretreated with only LE and samples pretreated with PO and1 mM Fe(III) + H 2 O 2 increased the methane production yield to 420 and 419 mL/g vS respectively. These pretreatments delignified SEBW up to 25 %. [ABSTRACT FROM AUTHOR]

• The AD performance of WRF-pretreated corn silage was investigated. • Selective fungi, P. ostreatus and D. squalens increased AD potential of corn silage. • Prolonged pretreatment times induced small increment in methane generation. • Increased incubation temperature partly inhibited AD due to H 2 S release. • Corn type influenced the efficiency of P. Ostreatus to increase methane generation. Corn silage was treated by white rot fungi (WRF) to investigate the effect of pretreatment on material's ability to produce methane in anaerobic digestion (AD). The selective fungi Pleurotus ostreatus and Dichomitus squalens promoted biogas generation, whereas the non-selective Trametes versicolor and Irpex lacteus had negative effect. Cumulative methane production after 10-day pretreatment with P. ostreatus at 28 °C rose 1.55-fold. The longer pretreatments of 30 and 60-days had smaller effect. When the pretreatment with P. ostreatus was carried out at 40 °C a high H 2 S release affected the AD process. Effect of WRF action dependent on the type of corn silage. With typical corn silage, the lignin depolymerisation raised the methane generation from 0.301 to 0.465 m3kg VS -1. In contrast, extensive decomposition of hemicellulose in hybrid corn silage deteriorated the effect of pretreatment on methane production. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this work was to explore the use of polluted water effluents from wheat straw using industries as inducers of lignocellulolytic enzymatic activities in cultures of white rot basidiomycetes. For this purpose, we studied the effect of a wheat straw water extract on the evolution of the laccase activity recovered from submerged cultures of Pleurotus ostreatus made in different media and under various culture conditions. Our results demonstrated an accumulative induction effect in all the cultures and conditions tested. This induction is parallel to changes in the laccase electrophoretic profiles recovered from the culture supernatants. The isoenzyme that appeared to be mainly responsible for the laccase activity under these conditions was laccase 10, as confirmed by sequencing the induced protein. These results support the idea of using wheat straw effluents as inducers in liquid cultures of P. ostreatus mycelia for the production of ligninolytic enzymatic cocktails. [Copyright &y& Elsevier]

Abstract: Laccases are oxidative enzymes linked to biological degradation of lignin. The aim of this work was to evaluate the effect of inducers and different concentrations of nitrogen on production level of total laccase activity and pattern of laccase isoforms, produced in solid state fermentation of sugarcane bagasse by a selected strain of Pleurotus ostreatus. The addition of yeast extract 5g/L, copper sulfate 150μM and ferulic acid 2mM provided highest enzymatic activity (167U/g) and zymograms indicated the presence of six laccase isoforms (POXA1b, POXA3, POXC and three other isoforms). Results of protein identification by mass spectrometry confirmed the presence of POXC and POXA3 as the main isoenzymes, and also identified a glyoxal oxidase and three galactose oxidases. The fact that the isoenzyme POXA1b was not identified in the analyzed samples can be possibly explained by its sensitivity to protease degradation. [Copyright &y& Elsevier]

Abstract: The influence of Pleurotus ostreatus inoculation on wood degradation and on fungal community structure was studied. The experiments were performed on an organically poor fly ash deposit covered with a 10cm layer of beech wood chips inoculated with P. ostreatus isolate ZIM76. Compared to non-inoculated wood chips, inoculation increased the temperatures and relative humidities and, in the first 6months, accelerated Klason lignin degradation by 9% and also, after 17months, increased iron translocation into wood chips by 30%. After 6months, PCR–DGGE showed 22–28 and 13–21 fungal taxa in non-inoculated and P. ostreatus-inoculated beech chips, respectively. The differences in number of taxa and in the fungal community structure (based on Dice coefficient) between non-inoculated and inoculated wood chips diminished with time. The results indicate that the naturally occurring processes of wood degradation are as efficient as those occurring in sites inoculated with P. ostreatus. [Copyright &y& Elsevier]

Abstract: The present work proposes the use of Pleurotus ostreatus immobilized on Amberlite XAD-4 as new biosorbent in trace metal determination. The effects of experimental parameters, such as “pH and flow rate of sample solution, amount of solid phase, eluent type, and concentration” on the recovery of the metal ions were investigated. Maximum adsorption of Cr(III), Cd(II) and Cu(II) ions took place in the pH range 4–5. These metal ions can be desorbed with 1M HCl (recovery 95–100%). 0.2g adsorbent amount and 2.5mLmin−1 flow rate was found to be optimum of all preconcentration experiments. The sorption capacity after 10 cycles of sorption and desorption does not vary more than 2.0%. The influences of the contaminant ions on the retentions of the analytes were also examined. The results showed that P. ostreatus immobilized on Amberlite XAD-4 can be considered as very promising material in trace metal determination. [Copyright &y& Elsevier]

Abstract: This study was aimed at developing a process of solid state fermentation (SSF) with the fungi Pleurotus ostreatus and Trametes versicolor on apple processing residues for wastewater decolorization. Both fungi were able to colonize apple residues without any addition of nutrients, material support or water. P. ostreatus produced the highest levels of laccases (up to 9Ug−1 of dry matter) and xylanases (up to 80Ug−1 of dry matter). A repeated batch decolorization experiment was set up with apple residues colonized by P. ostreatus, achieving 50% decolorization and 100% detoxification after 24h, and, adding fresh wastewater every 24h, a constant decolorization of 50% was measured for at least 1month. A continuous decolorization experiment was set up by a packed-bed reactor based on colonized apple residues achieving a performance of 100mg dye L−1 day−1 at a retention time of 50h. [Copyright &y& Elsevier]

Abstract: The growth of Pleurotus ostreatus was analyzed on three particle sizes of sugar cane bagasse: 0.92mm and1.68mm in diameter, in addition to heterogeneous fibers (average 2.9mm in diameter). Specific growth rate on heterogeneous particles was lower (μ =0.043h−1), although soluble protein production was maximal (809μg/g dry wt). Higher μ values were reached on the other two particles sizes (0.049–0.05h−1) with less soluble protein (500μg/g dry wt). Xylanases and laccases were favored in heterogeneous particles; while the highest selectivity for xylanases over cellulases was observed in 1.68mm particles, corresponding with the maximal hemicellulose breakdown. Lignin and cellulose were preferentially degraded in smallest particles. This study shows that the geometrical ratio, shape and size of sugar cane bagasse fibers strongly influence packing density for SSF substrate, with an impact in the production of extracellular enzymes, growth rates and composition changes in substrate. [ABSTRACT FROM AUTHOR]

Abstract: Pleurotus ostreatus and Pleurotus sajor-caju were studied for their ability to produce laccase and carboxymethylcellulase (CMCase) enzymes on different agricultural wastes under solid state fermentation. The spawns of P. ostreatus and P. sajor-caju were inoculated on different agricultural wastes including viticulture wastes, wheat straw, paddy straw, sesame straw, sawdust as well as the mixtures of these wastes with wheat bran. The carbon and nitrogen contents of substrates containing bran were the highest. The laccase activities of P. ostreatus and P. sajor-caju reached the highest values on the day 10 of mycelial growth. This enzyme activity was higher on the substrates containing bran which had high nitrogen and low C/N ratio than the other tested substrates with no bran. The CMCase activities of P. sajor-caju and P. ostreatus had two peaks on the 5th day of mycelial growth and after first flash. P. ostreatus and P. sajor-caju grown on substrates containing wheat bran had higher biological efficiencies and total yields as well as higher CMCase and laccase activities. [Copyright &y& Elsevier]

Abstract: The aims of the current study were to follow: (1) the capability of the edible mushroom Pleurotus ostreatus to degrade cell wall components and soluble phenols of the olive mill solid waste (OMSW), and improve it for ruminant nutrition (2) the fate of oil and the lipid-soluble compounds tocopherols, squalene and β-sitosterol in the fermented OMSW. A significant decrease in oil and lipid-soluble compounds with a concomitant shift in the fatty acid profile and degradation of soluble phenols took place already after 14d. The utilization of lipids by the fungus shifted the degradation of the structural carbohydrates to a later stage, and significantly reduced the metabolizable energy of the OMSW. We propose that edible fungi with reduced lipase activity would preserve the energy and health promoting ingredients of the oil, and force the fungus to degrade structural carbohydrates, thus improving its digestibility. [Copyright &y& Elsevier]

Abstract: A novel water-soluble polysaccharide (POPS-1) was obtained from the fruiting bodies of Pleurotus ostreatus by hot water extraction, ethanol precipitation, and fractionated by DEAE-cellulose ion exchange chromatography and sepharose CL-6B gel filtration chromatography using an ÄTKA explore 100 purifier. The structure characterization and antitumor activity of the POPS-1 were evaluated in this paper. According to GC analysis, HPGPC, FT-IR, partial acid hydrolysis, periodate oxidation and Smith degradation, methylation and GC–MS analysis, the results indicate POPS-1 (M w =31kDa) was composed of Man; Gal; Glc with a molar ratio of 1:2.1:7.9, it had a backbone of β-(1→3)-linked glucose residues, which occasionally branches at O-6. The branches were composed of (1→3)-linked Glc, (1→4)-linked Gal, (1→4)-linked Man, and terminated with Glc and Gal residues. Cytotoxicity assay showed POPS-1 presented significantly higher antitumor activity against Hela tumor cell in vitro, in a dose-dependent manner, and exhibited significantly lower cytotoxicity to human embryo kidney 293T cells than Hela tumor cells compared with 5-Fu. The results suggest POPS-1 may be considered as a potential candidate for developing a novel low toxicity antitumor agent. [Copyright &y& Elsevier]

Abstract: Two novel two-step pretreatments for enzymatic hydrolysis of rice hull (RH) were proposed to lower the severity requirement of fungal pretreatment time. They consisted of a mild physical or chemical step (ultrasonic and H2O2) and a subsequent biological treatment (Pleurotus ostreatus). The combined pretreatments led to significant increases of the lignin degradation than those of one step pretreatments. After enzymatic hydrolysis of the pretreated RH, the net yields of total soluble sugar (TS) and glucose (G) increased greatly. The combined pretreatment of H2O2 (2%, 48h) and P. ostreatus (18d) was more effective than sole pretreatment of P. ostreatus for 60d. It could remarkably shorten the residence time and reduce the losses of carbohydrates. Ligninase analyses and SEM observations indicated that the enhancing of the efficiency could possibly attribute to the structure disruption of the RH during the first pretreatment step. So, the combined pretreatment could be recommended to different lignocellulosic materials for enzyme based conversions. [Copyright &y& Elsevier]

Abstract: The water-soluble polysaccharide (POP), with a molecular mass of 2.4×104 Da, was obtained from the fruiting body of Pleurotus ostreatus. Structure features of the purified polysaccharide were investigated by a combination of chemical and instrumental analysis, such as methylation analysis, Smith degradation, GC-MS, 13C and 1H NMR and FTIR. The results indicated that the backbone of POP was composed of (1→6)-linked-α-d-galactopyranosyl and (1→2,6)-linked-α-d-galactopyranosyl residues, which were terminated with a single terminal (1→)-β-d-glucose residue at the O-2 position of galactosyl along the main chain in the ratio of 1:1:1. Preliminary tests in vitro showed POP is capable of enhancing concanavalin A (ConA)- or lipopolysaccharide (LPS)-induced lymphocyte proliferation, which suggested that POP could be a potential immunostimulating agent for use in functional foods or medicine against both pathogens and cancer. [Copyright &y& Elsevier]

Abstract: Two strains of Pleurotus ostreatus (IE-8 and CP-50) were grown on defined medium added with wheat straw extract (WSE). Mycelia from these cultures were used as an inoculum for solid fermentation using sugar cane bagasse (C:N=142). This substrate was used separately either as a mixture of heterogeneous particle sizes (average size 2.9mm) or as batches with two different particle sizes (0.92mm and 1.68mm). Protein enrichment and production of lignocellulolytic enzymes on each particle size was compared. The effect of ammonium sulphate (AS) addition was also analyzed (modified C:N=20), this compound favored higher levels of protein content. Strain CP-50 showed the highest increase of protein content (48% on particle size of 1.68mm) when compared to media with no additional N source. However, strain IE-8 produced the highest levels of all enzymes: xylanases (5.79IU/g dry wt on heterogeneous particles) and cellulases (0.18IU/g dry wt on smallest particles), both without the addition of AS. The highest laccase activity (0.040IU/g dry wt) was obtained on particles of 1.68mm in the presence of AS. Since effect of particle size and addition AS was different for each strain, these criteria should be considered for diverse biotechnological applications. [Copyright &y& Elsevier]

Abstract: Solid-state 13C nuclear magnetic resonance (NMR) and elemental analysis techniques were used to monitor the degradation of wheat bran by the white-rot fungus Pleurotus ostreatus during a 62-day cultivation period. The weight loss and in vitro organic matter digestibility of the substrate were also evaluated after fungal treatment. The 13C NMR spectra of degraded wheat bran samples showed a lower content in carbohydrates and a higher content in aliphatic and carboxylic groups than the untreated control sample. In parallel, changes in the wheat bran elemental composition evidenced a decrease in carbon content and a concomitant increase in nitrogen and oxygen content during mycelium growth. These results clearly indicate the occurrence of progressive changes in the composition of wheat bran during fungal treatment and are interpreted in terms of preferential degradation of amorphous vs. crystalline polysaccharides by the fungal mycelium and accumulation of proteins in the substrate. At the end of the cultivation period, the treated samples experienced an average weight loss of 20% and an increase in organic matter digestibility of 17%. [Copyright &y& Elsevier]

Abstract: Pleurotus species are recognized for producing β-glucans with important medicinal properties as a constituent of the cellular wall of the fruiting body or of the mycelium. The aims of this work were to select a culture medium that maximized the production of biomass and polysaccharides produced by Pleurotus ostreatus DSM 1833 and to evaluate the selected medium in two values of initial oxygen transfer rate –K L a (10.2 and 19.3h−1). A 2∗∗4 factorial design was constructed to evaluate the supplementation of wheat extract with corn steep liquor – CSL (10 or 20gL−1), yeast extract – YE (2 or 5gL−1), ammonium sulfate – AS (0 or 5gL−1) and glucose (20 or 40gL−1). In terms of maximum productivity in biomass and global productivity in polysaccharides, the best values were obtained when 5gL−1 of YE and 40gL−1 of glucose were used. In terms of maximum concentration of biomass, the best results were obtained when 20gL−1 of CSL and 40gL−1 of glucose were used. The best results in terms of production of biomass and polysaccharides were achieved when lower initial K L a (10.2h−1) was used. [Copyright &y& Elsevier]

Abstract: In this study, cultivation of oyster mushroom, Pleurotus ostreatus, on wheat straw substrate containing tap water and olive mill effluent (OME) mixture containing varying volume of OME was studied in order to investigate the feasibility of using OME as an alternative wetting agent and OME’s impact on some fundamental food quality characteristics of mushrooms. Time period for mycelial colonization, primordium initiation and first harvest were comparatively evaluated with the control group. It was shown that the use of OME and tap water mixture consisting of OME up to 25% volumetrically was possible for the purpose of commercial mushroom production. Experimental results obtained from substrate containing 25% OME mixture showed no statistically significant difference compared to control group. The negative effects of increasing volume of OME in the mixture were also indicated by bioefficiency, which was found to be 13.8% for substrates wetted with 100% OME, whereas bioefficiency was 53.6% for control group. Increasing volume of OME in the mixture resulted in deformation of fruit body shape, whereas no significant difference in food quality was observed due to the higher amount of OME. This work suggested that the use of OME up to 25% as moisturizer could be considered, especially for the locations having significant number of olive mills and mushroom producers, both as an environmentally friendly solution for the safe and ecological disposal of OME and a practical way for recovering OME’s economic value thereby. [Copyright &y& Elsevier]

Abstract: Oyster mushroom, Pleurotus ostreatus (Jacq.:Fr.) Kumm. ITCC 3308 (collected from Indian Type Culture Collection, IARI, New Delhi, India, 110012) was grown on dry weed plants, Leonotis sp, Sida acuta, Parthenium argentatum, Ageratum conyzoides, Cassia sophera, Tephrosia purpurea and Lantana camara. Leonotis sp. was the best substrate in fruit body production of P. ostreatus when it was mixed with rice straw (1:1, wet wt/wet wt) for mushroom cultivation. The fruiting time for P. ostreatus was also less on Leonotis sp. than on any other weed substrates tested in the present investigation. T. purpurea was the least suited weed for oyster mushroom cultivation. The main problem of oyster mushroom cultivation on weed substrates was found to be low yield in the second flush that could be overcome by blending weed plants with rice straw. The protein contents of the fruit bodies obtained from Cassia sophera, Parthenium argentatum and Leonotis sp. were not only better than rice straw but also from the rice straw supplemented weeds. [Copyright &y& Elsevier]

The use of wooden crates for composting a mixture of 70% grass, (Digitaria decumbens), and 30% coffee pulp, combined with 2% Ca(OH)2, was studied as a method for preparing substrate for the cultivation of Pleurotus ostreatus. Crate composting considerably modified the temperature pattern of the substrate in process, as compared to pile composting, where lower temperatures and less homogeneous distributions were observed. Biological efficiencies varied between 59.79% and 93% in the two harvests. Based on statistical analysis significant differences were observed between the treatments, composting times and in the interactions between these two factors. We concluded that it is possible to produce P. ostreatus on a lignocellulosic, non-composted, non-pasteurized substrate with an initial pH of 8.7, and that composting for two to three days improves the biological efficiency. [Copyright &y& Elsevier]

The mycelial growth rates in lineal growth assay, yield, and production rate of five Pleurotus ostreatus strains were evaluated in response to different levels of Mn(II) and/or NH4+ in a substrate containing sunflower seed hulls as a main energy and nutritional component. Each strain showed different basal values for mycelial growth rate and biological efficiency on sunflower seed-hull substrate. Adding growth limiting mineral nutrients increased the mycelial growth rate by 13–25%. Primordia initiation for the first flush appeared between day 24 and 28 and days to the second crop ranged from 39 to 51. Biological efficiency increased over control values and reached 60–112%, depending on the strain and the concentration of Mn(II) and NH4+. This study demonstrated the advantage of selecting the most productive P. ostreatus strains in a substrate formulated with sunflower seed hulls to provide the main energy and nutritional ingredients and supplemented with Mn(II) and/or NH4+. [Copyright &y& Elsevier]

Cultivation of the oyster mushroom, Pleurotus sajor-caju, on rice and wheat straw without nutrient supplementation was investigated. The effects of straw size reduction method and particle size, spawn inoculation level, and type of substrate (rice straw versus wheat straw) on mushroom yield, biological efficiency, bioconversion efficiency, and substrate degradation were determined. Two size reduction methods, grinding and chopping, were compared. The ground straw yielded higher mushroom growth rate and yield than the chopped straw. The growth cycles of mushrooms with the ground substrate were five days shorter than with the chopped straw for a similar particle size. However, it was found that when the straw was ground into particles that were too small, the mushroom yield decreased. With the three spawn levels tested (12%, 16% and 18%), the 12% level resulted in significantly lower mushroom yield than the other two levels. Comparing rice straw with wheat straw, rice straw yielded about 10% more mushrooms than wheat straw under the same cultivation conditions. The dry matter loss of the substrate after mushroom growth varied from 30.1% to 44.3%. The straw fiber remaining after fungal utilization was not as degradable as the original straw fiber, indicating that the fungal fermentation did not improve the feed value of the straw. [Copyright &y& Elsevier]

• The lignin degradation of combined bacteria is more significant than single bacteria. • The combined bacteria showed good correlation and coordination mechanism. • Best degrade conditions were TEMP 32 °C, pH 3.5, solid-liquid ratio 10%, for 20 days. In this study, the combined bacteria (CB) were constructed by Phanerochaete chrysosporium , Trametes versicolor and Pleurotus ostreatus , which have a good ability to degrade lignocellulose, and the optimum degradation conditions and internal degradation mechanism of combined bacteria were investigated. The results showed that under conditions of temperature (32 °C), pH (3.5), solid-liquid ratio (10%), culture time (20 d), the degradation rates of lignin, cellulose and hemicellulose were 43.36%, 31.29%, 48.36%, respectively. The construction of combined bacteria significantly enhances the degradation ability of lignocellulose, and showed good correlation and coordination mechanism. [ABSTRACT FROM AUTHOR]

• White-rot fungi pretreatment improved corn straw's nutritive value by delignification. • Lentinus edodes and Pleurotus eryngii had the highest potency to degrade lignin. • Optimal length to treat corn straw by Lentinus edodes and Pleurotus eryngii was ~28 d. Five white-rot fungi Pleurotus ostreatus , Lentinus edodes , Hericium erinaceus , Pleurotus eryngii and Flammulina filiformis were studied (solid-state incubation and in vitro gas production) to determine lignin degradation and optimal duration of fermentation of corn straw. All fungi significantly decreased lignin, with optimal reductions after 28 d. Although cellulose also decreased, L. edodes and P. eryngii minimized these losses. In intro dry matter digestibility, total volatile fatty acid concentration and total gas production of fermented corn straw decreased (P < 0.001) as fermentation was prolonged, with improved rumen fermentability for all fungal treatments except F. filiformis. Total gas production in L. edodes did not decrease but peaked on day 28, whereas F. filiformis reduced methane emission. In conclusion, fermentation of corn straw with P. eryngii or L. edodes for 28 d degraded lignin and improved nutritional value as ruminant feed. [ABSTRACT FROM AUTHOR]

• Xylanase, Laccase and Protease activities increased as the composting progressed. • The succession of microbiota was detected in corncob composting. • Firmicutes replaced Proteobacteria as the dominant phylum at thermophilic stage. • The succession of metabolism function of microbial community was explored. Metagenomic sequencing was used to reveal the dynamic changes in microbiota and the metabolic functions in corncob composting for preparing cultivation medium of Pleurotus ostreatus. Results showed that the changes of physicochemical properties lead to different dominant phylum at different stages of composting. Firmicutes replaced Proteobacteria as the dominant phylum at thermophilic stage. Correlation analysis indicated that the succession of microbiota was significantly affected by the C/N ratio, pH, temperature and organic matters in compost. The changes in community inevitably lead to the differences of metabolic functions. Metabolism analysis indicated that carbohydrate, lipid and amino acid metabolism were relatively higher in thermophilic stage. Conversely, the metabolism of starch, sucrose, galactose, ascorbate was mainly detected in the late stage. The metabolisms of different stages were driven by different microorganisms. Overall, these findings deepened our understanding of metabolic functions, and it is of great value to the metabolomics research of composting system. [ABSTRACT FROM AUTHOR]

• P. ostreatus modification of rice straw was multi-perspective analyzed. • P. ostreatus has a high lignocellulose degradation enzymes activity on rice straw. • Physicochemical properties change of rice straw facilitated its enzymes adsorption. • P. ostreatus modification for 25 d increased methane yield of rice straw by 26.9%. Multi-perspective analyses were carried out to investigate the effect of rice straw modification for 45 days by P. ostreatus on biomethane of production. The results showed that rice straw modified for 25 days achieved the highest biomethane yield of 269 mL·g−1 VS, which was a 26.9% improvement compared with non-modified rice straw. The multi-perspective analyses demonstrated that the improvement resulted from fungal enzymatic reactions, which led to changes in the physicochemical properties of rice straw. The porosity, surface area, acetyl group abundance, degree of polymerization, and lignin degradation selectivity of rice straw modified for 25 days were optimal for enzyme adsorption. Compared with non-modified rice straw, the adsorption of cellulase and xylanase on rice straw modified for 25 days was increased by 18.8% and 58.1%, respectively, which facilitated biomethane production. The study indicated that P. ostreatus is effective for improving biomethane production from rice straw. [ABSTRACT FROM AUTHOR]

• Anaerobic digesters processing dairy manure and food waste produce solid residues. • Digestate solids were tested as substrate ingredients in P. ostreatus cultivation. • Substrate recipes including 15% digestate solids by dry matter produced high yields. • Much N and P recovered in mushrooms, leaving useful spent mushroom substrate. • Mushroom cultivation can divert nutrients into edible food without land application. State-level policies in the New England region of the United States require diversion of organic materials away from landfills. One management option for food waste is anaerobic co-digestion with dairy manure. In addition to biogas, anaerobic digestion produces separated solid and liquid digestates. Solid digestates in the region are typically recycled as animal bedding before returning to the digester and liquids are used to fertilize local soils. Repeated land application of nutrients can contribute to eutrophication risk over time and alternative models are needed to convert digestates into valuable export products. We tested solid digestates derived from dairy manure and food waste as substrate ingredients in the cultivation of Pleurotus ostreatus. We show these materials can be used to offset non-local substrate ingredients while achieving mushroom yields comparable to commercial recipes. This strategy could help divert nutrients away from land adjacent to digesters and into safe, protein-rich food, while producing useful spent mushroom substrate. [ABSTRACT FROM AUTHOR]

Spawn running, pin head and fruit body formation, and mushroom yield of oyster mushroom (Pleurotus ostreatus) on waste paper supplemented with peat, chicken manure and husk rice (90 + 10; 80 + 20 w:w) were studied. The fastest spawn running (mycelia development) (15.8 days), pin head formation (21.4 days) and fruit body formation (25.6 days), and the highest yield (350.2 gr) were realized with the substrate composed of 20% rice husk in weight. In general, increasing the ratio of rice husk within the substrate accelerated spawn running, pin head and fruit body formation, and resulted in increased mushroom yields, while more peat and chicken manure had a negative effect on growing. [Copyright &y& Elsevier]