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[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]

• 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]