Eryngii Research Articles

Drying kinetics of Pleurotus eryngii slices during hot air drying

Abstract Hot air drying is widely adopted to extend the shelf life of Pleurotus eryngii, which is an edible fungus with high nutritional value and large market demand. Understanding moisture transfer during hot air drying is essential for both quality improvement and energy-efficient dryer design. In this study, we investigated the drying kinetics of P. eryngii slices with different thicknesses (4, 8, and 12 mm) under different hot air temperature levels (40, 50, 60, 70, and 80°C) and a constant air velocity (2 m/s). It is found that the drying rate increases with the increase of the hot air temperature or the decrease of the thickness of P. eryngii slices. Only a falling rate period was observed during the hot air drying. We used eight mathematical models to describe the drying kinetics of P. eryngii slices and found that the logarithmic model fits the experimental data best. The fitted effective moisture diffusivity of P. eryngii slices is in the range of 3.34 × 10 − 9 3.34\times {10}^{-9} to 2.25 × 10 − 9 m 2 / s 2.25\times {10}^{-9}{\text{ m}}^{2}/\text{s} , and the fitted drying activation energy is 19.30 kJ/mol, agreeing with the results in the literature. Additionally, we noticed that the color of dried P. eryngii slices becomes darker with the increase of hot air temperature due to the Maillard browning reaction. This study helps to understand the drying kinetics of P. eryngii slices during the hot air drying and guides the drying process optimization.

Biochemical Evaluation of Agaricus and Pleurotus Strains in Batch Cultures for Production Optimization of Valuable Metabolites

The production of various biochemical compounds such as proteins, glucans and glucanases, from the mycelium of four strains of Basidiomycetes species, Agaricus bisporus, Agaricus subrufescens, Pleurotus eryngii and Pleurotus ostreatus, during batch culture in shaking flasks, was studied. Fungi were cultured for 26 days in defined media with glucose as carbon source and were primarily evaluated for their ability to consume glucose and produce mycelial mass and intracellular polysaccharides (IPS). Results showed that on the 26th day of cultivation, P. ostreatus produced the maximum biomass (16.75 g/L), whereas P. eryngii showed the maximum IPS concentration (3.82 g/L). All strains presented a similar pattern in total protein production, with A. bisporus having the highest percentage of total proteins (36%, w/w). The calculated correlation coefficients among ribonucleic acid (RNA) vs. biomass (0.97) and RNA vs. protein (0.97) indicated a very strong relation between RNA and biomass/protein synthesis. The studied strains exhibited an increase in total glucan and glucanase (β-1,6) production during cultivation, with A. bisporus reaching the highest glucan percentage (8%, w/w) and glucanase activity (12.7 units/g biomass). Subsequently, processed analytical data were used in contour-graph analysis for data extrapolation to optimize future continuous culture.

Chitin-glucan composite sponge hemostat with rapid shape-memory from Pleurotus eryngii for puncture wound

Efficient hemostasis is a great challenge for treating the inaccessible hemorrhage wounds. A novel shape-memory chitin-glucan hemostatic sponge (ATC-Sponge) is constructed via sequentially in-situ removal of protein and glucan from Pleurotus eryngii fruiting body, TEMPO oxidation and Ca2+ crosslinking. The sponge displays interconnected microporous structure with high water absorption and robust mechanical properties. The sponge at dry state shows rapid blood-triggered shape-memory, allowing easy insertion into the puncture wound in a compressed fixed-shape and the subsequent quick volume expansion to conform wound shape to stop bleeding. Compared with standard medical gauze and gelatin sponge, ATC-Sponge demonstrates superior hemostatic performance in the rat femoral artery and non-compressive liver puncture injury models. Additionally, ATC-Sponge can effectively accelerate wound healing. This multi-functional shape-memory ATC-Sponge shows high potential in controlling the bleeding of inaccessible traumas.

The effect of inoculation Leuconostoc mesenteroides and Lactiplantibacillus planetarium on the quality of Pleurotus eryngii Jiaosu

To investigate the effects of inoculating Leuconostoc mesenteroides or Lactiplantibacillus planetarium on the changes in metabolites in Pleurotus eryngii Jiaosu, a fermented plant extract rich in nutrients and bioactive compounds, the physicochemical and metabolite features of the treated Jiaosu were compared to those of spontaneously-fermented Jiaosu. The physicochemical features of Jiaosu fermented with Leuconostoc mesenteroides or Lactiplantibacillus planetarium were superior to spontaneously-fermented Jiaosu. An Partial Least Squares Discrimination Analysis (PLS-DA) score plot showed a clear difference in metabolites between spontaneous fermentation group (SFG) and inoculated Lactiplantibacillus planetarium group (LPG). Metabolites were remarkably different between LPG and SFG on the first day of fermentation. The differential metabolites included sugars, acids and alcohols. This study highlights the applicability of GC-MS based metabolomics as a tool to monitor Jiaosu fermentation.

Potential Uses of Scallop Shell Powder as a Substrate for the Cultivation of King Oyster Mushroom (Pleurotus eryngii)

Scallop shells are currently a major form of waste generated in the Chinese fishing industry. However, they have the potential to be used as important industrial products. This study was conducted to assess the utility of scallop shell powder (SSP) supplementation in improving the growth of king oyster mushrooms (Pleurotus eryngii) grown on sawdust and sugarcane bagasse substrates. The outcomes of interest included mycelial growth, yield, biological efficiency, fruiting body traits, nutrient supply, and the mineral composition of P. eryngii. Supplementation with SSP accelerated the mycelial growth of P. eryngii. The yield of fruiting bodies (399.5 g/bag) and the biological efficiency (84.6%) were 14% higher after supplementation of the substrate with 2% SSP compared with those of mushrooms grown on substrates not supplemented with SSP (349.8 g/bag and 74.0%, respectively). Moreover, the crude protein and fiber contents of the fruiting bodies significantly improved after growth with SSP. Furthermore, supplementation with 2% SSP increased the calcium (Ca) content of the fruiting bodies of P. eryngii by 64% (to 67.2 ± 15.7 mg kg−1) compared with that of mushrooms grown on a control substrate (41.0 mg kg−1). This study revealed that P. eryngii can efficiently use the Ca provided by raw SSP, generating higher Ca contents in their fruiting bodies. Our results demonstrate that the supplementation of substrates with SSP can be useful for enhancing both the yield and nutritional content of P. eryngii.

Biofortification of Three Cultivated Mushroom Species with Three Iron Salts-Potential for a New Iron-Rich Superfood.

Mushrooms fortified with iron (Fe) can offer a promising alternative to counter the worldwide deficiency problem. However, the factors that may influence the efficiency of fortification have not yet been fully investigated. The aim of this study was to compare the effects of three Fe forms (FeCl3 6H2O, FeSO4 7H2O, or FeHBED) in three concentrations (5, 10, or 50 mM) for three mushroom species (Pleurotus eryngii, P. ostreatus, or Pholiota nameko) on their chemical composition, phenolic compounds, and organic acid production. The most effective metal accumulation of all the investigated species was for the 50 mM addition. FeCl3 6H2O was the most favorable additive for P. eryngii and P. nameko (up to 145 and 185% Fe more than in the control, respectively) and FeHBED for P. ostreatus (up to 108% Fe more than in control). Additionally, P. nameko showed the highest Fe accumulation among studied species (89.2 ± 7.51 mg kg−1 DW). The creation of phenolic acids was generally inhibited by Fe salt supplementation. However, an increasing effect on phenolic acid concentration was observed for P. ostreatus cultivated at 5 mM FeCl3 6H2O and for P. eryngii cultivated at 5 mM FeCl3 6H2O and 5 mM FeSO4 7H2O. In the case of organic acids, a similar situation was observed. For P. ostreatus, FeSO4 7H2O and FeHBED salts increased the formation of the determined organic acids in fruiting bodies. P. eryngii and P. nameko were characterized by a much lower content of organic acids in the systems supplemented with Fe. Based on the obtained results, we recommend starting fortification by preliminarily indicating which form of the element is preferred for the species of interest for supplementation. It also seems that using an additive concentration of 50 mM or higher is most effective.

The Activity and Gene Expression of Enzymes in Mycelia of Pleurotus Eryngii under Cadmium Stress

Cadmium (Cd) is a highly toxic pollutant and a nonessential element for plant growth. Here, we investigated the levels of malondialdehyde (MDA), H2O2, sugars, and the activity and gene expression of antioxidant enzymes and sugar metabolism-related enzymes in the mycelia of Pleurotus eryngii grown in the presence of 0, 0.5, 1, 1.5, 2.0, and 4.0 mg·L−1 Cd. Raising Cd concentration resulted in increases, followed by decreases in the levels of malondialdehyde (MDA) and H2O2 in the mycelia. The maximum concentrations of MDA and H2O2 reached 318.61 and 7411.40 μmol·L−1, respectively, at a Cd concentration of 1 mg·L−1. Antioxidative enzymes (superoxide dismutase (SOD), catalase, glutathione peroxidase (GPX), and ascorbate peroxidase (APX)) activities peaked at 1 mg·L−1 Cd. Furthermore, Pleurotus eryngii produced trehalose, glucose, fructose, and maltose in the fermentation broth in response to Cd stress. The levels of trehalose, arabinose, and fructose in the fermentation broth decreased continuously. The levels of glucose increased continuously, whereas those of maltose first increased and then decreased. Gene expression level of chitin synthase, glucose-1-phosphate uridyl transferase peaked significantly at 2 mg·L−1 of Cd, while that of trehalase 2 is 0.5 mg·L−1, and those for fructose-diphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, reached the maximum at 4 mg·L−1.

Immunomodulating Activity of Pleurotus eryngii Mushrooms Following Their In Vitro Fermentation by Human Fecal Microbiota.

Recent studies have revealed the crucial role of several edible mushrooms and fungal compounds, mainly polysaccharides, in human health and disease. The investigation of the immunomodulating effects of mushroom polysaccharides, especially β-glucans, and the link between their anticancer and immunomodulatory properties with their possible prebiotic activity on gut micro-organisms has been the subject of intense research over the last decade. We investigated the immunomodulating effects of Pleurotus eryngii mushrooms, selected due to their high β-glucan content, strong lactogenic effect, and potent geno-protective properties, following in vitro fermentation by fecal inocula from healthy elderly volunteers (>60 years old). The immunomodulating properties of the fermentation supernatants (FSs) were initially investigated in U937-derived human macrophages. Gene expression as well as pro- (TNF-α, IL-1β) and anti-inflammatory cytokines (IL-10, IL-1Rα) were assessed and correlated with the fermentation process. The presence of P. eryngii in the fermentation process led to modifications in immune response, as indicated by the altered gene expression and levels of the cytokines examined, a finding consistent for all volunteers. The FSs immunomodulating effect on the volunteers’ peripheral blood mononuclear cells (PBMCs) was verified through the use of cytometry by time of flight (CyTOF) analysis.

Nitric oxide enhances resistance of Pleurotus eryngii to cadmium stress by alleviating oxidative damage and regulating of short-chain dehydrogenase/reductase family.

The function and mechanism of nitric oxide (NO) in regulating Pleurotus eryngii biological response to cadmium (Cd) stress was evaluated by using anti-oxidation and short-chain dehydrogenase/reductase (SDR) family analysis. The fresh biomass of P. eryngii mycelia sharply decreased after treatment with 50µM Cd; the lipid peroxidation and H2O2 accumulation in P. eryngii were found responsible for it. Proper exogenous supply of NO (150µM SNP) alleviated the oxidative damage induced by Cd stress in P. eryngii, which reduced the accumulation of thiobarbituric acid reactive substances (TBARS) and H2O2. The activities of antioxidant enzymes (superoxide dismutase, peroxidase) were significantly increased to deal with Cd stress when treated with SNP (150µM), and the content of proline was also closely related to NO-mediated reduction of Cd toxicity. Moreover, SDR family members were widely involved in the response to Cd stress, especially PleSCH70 gene was observed for the first time in participating in NO-mediated enhancement of Cd tolerance in P. eryngii. Taken together, this study provides new insights in understanding the tolerance mechanisms of P. eryngii to heavy metal and lays a foundation for molecular breeding of P. eryngii to improve its tolerance to environmental stress.

Siyah Alacalarda Beyaz Çürükçül Funguslar Kullanılarak Buğday Samanın İn-Situ Parçalanabilirliğinin Belirlenmesi

The Phanerochaete chrysosporium (PC) and Pleurotus eryngii (PE) were observed for their potential to increase the in situ dry matter (DM) and crude protein (CP) degradability of wheat straw. The wheat straw samples were inoculated with the PC and PE fungi (10% weight/volum) and incubated under solid state fermentation conditions at 30 ◦C for 30 days to determine their in-situ degradability and chemical composition. In situ ruminal degradability was determined by using four ruminal cannulated Holstein bulls (approximately 400 kg BW) fed on a diet a concentrate-to-roughage ratio of 45:55 (dry matter (DM) basis). The samples were incubated in nylon bags for 0, 4, 8, 16, 24, 48, 72 and 96 h in the rumen. The results showed that increased in situ ruminal degradation of DM and CP in PC and PE groups in comparison to the control group (P < 0.01). The wheat straw incubated with PC had the greatest in situ DM degradability after incubation for 24 h (P < 0.01). The inoculation of PC and PE increased in situ ruminal crude protein (CP) degradation (P < 0.01) in comparison to the other treatments. As a result, the fungal inoculants and urea treatment increased the degradability of DM and CP in wheat straw.

Evaluation of Antioxidant and Antibacterial Activities of the Polysaccharides from Mycelium and the Culture Medium of Pleurotus Eryngii Strain UN-1

Pleurotus eryngii was one of the most precious and ordinary edible mushrooms, and its polysaccharides were the major active substances. In this study, P. eryngii strain UN-1 was cultured in a liquid medium at 25℃ under a shaking of 80 rpm for 7 days. Two crude polysaccharides named CPN and CPNM were obtained from the mycelium of P. eryngii UN-1 and its broth culture medium, respectively. After partial purification by cellulose DEAE-52 column chromatography and Sephadex G-100 gel-filtration, two fractions (PNP-1 and PNP-2) from CPN and one (PNMP-1) from CPNM were eluted and subjected to physicochemical properties, antioxidant, and antibacterial activities, in addition, the crude polysaccharides. The in vitro antioxidant assay revealed that all samples showed moderate scavenging capacities on DPPH radical (6.31-80.92%), ABTS radical (9.33-67.26%), and hydroxyl radical (11.21-79.53%) at different concentrations (0-2000 μg/mL), and PNP-2 exhibited the highest scavenging activity for all tested free radicals. Moreover, the antibacterial activity of the most active fraction (PNP-2) showed a significant effect against Escherichia coli, Bacillus Subtillis, Salmonella enterica, and Staphylococcus aureus subsp. Aureus strains with Minimum Inhibitory Concentration (MIC) values (2.5, 5, 2.5 and 5 mg/mL, respectively). Notably, the UV-vis Spectrophotometer confirmed that multiple active known compounds such as uremic acid were detected in all tested fractions, which confirmed the antioxidant and antimicrobial activities obtained in this study. Conclusively, the polysaccharides obtained from P. eryngii UN-1 have the potential to act as a functional food ingredient or a preventive drug against human pathogenic bacteria.

Secondary Metabolites Produced by Coculture of Pleurotus ostreatus SY10 and Pleurotus eryngii SY302.

A new isovaleryl-monoterpene, pleurotusin A (1), and a new cyclopentenone derivative, pleurotusin B (7), together with five related known terpenoids (2-6), were isolated from the coculture broth of two edible fungi, Pleurotus ostreatus SY10 and Pleurotus eryngii SY302. The absolute configurations of 1 and 7 were elucidated by comprehensively using the density functional theory calculation of NMR and ECD data, DP4+ probability analysis, Mo2 (OAc)4 -based CD experiment and optical rotation. The antimicrobial activities of these compounds except for the unstable compound 7, were evaluated against two types of human-pathogenic fungi, Candida albicans and Cryptococcus neoformans, and three types of human-pathogenic bacteria, Staphylococcus aureus, Escherichia coli, and Shigella sp. Compound 1 displayed moderate activity against S. aureus with an MIC50 value of 90.3 μM. In addition, the antioxidant activities of high-yielding 2-6 were tested using DPPH, and compound 4 showed moderate activity with an EC50 value of 573 μM.

In Vitro Screening of New Biological Limiters against Some of the Main Soil-Borne Phytopathogens

This study explored the role of Aphanocladium album (strain MX95), Pleurotus ostreatus (strain ALPO) and Pleurotus eryngii (strain AL142PE) as potential biological limiters. MX95, ALPO and AL142PE were screened under laboratory studies against Phytophthora nicotianae (PN), Fusarium oxysporum f. sp. radicis-lycopersici (FORL), Fusarium oxysporum f. sp. lycopersici (FOL), Fusarium solani (FS), Sclerotinia minor (SM), Sclerotinia sclerotiorum (SS), Athelia (Sclerotium) rolfsii (AR) and Verticillium dahliae (VD). The radial growth inhibition and the over-growth of potential antagonists on the target organisms were used to assess the interactions in the in vitro dual culture plate assay. The antagonistic ability of each challenge isolate was evaluated by calculating an index of the antagonism (AI) based on the interaction type in the dual cultures. MX95, reducing the growth of SS (20%) and FS (40%), displayed deadlock at mycelial contact against FOL and FORL, deadlock at distance versus VD and completely over-grew PN and SM. ALPO reduced (43 to 88%) the mycelial growth of tested pathogens except FORL and replaced PN and VD. AL142PE reducing (53 to 67%) SS, VD, FS and FOL mycelial growth and completely over-grew PN. AR showed combative ability against all the experienced biological limiters. Based on the results of the AI values, MX95 (AI = 16.5) was considered an active antagonist, while ALPO (AI = 11.5) and AL142PE (AI = 12.0) were moderately active antagonists. Strains MX95, ALPO and AL142PE were suitable as environment-friendly potential biocontrol agents to manage some of the main soil-borne agents of foot, root, soft rot and wilt diseases. These results are the first step in the assessment of the potential capacity of these organisms as biological limiters. Nevertheless, additional experiments should be performed for the translation to the field conditions in plant protection against soil-borne plant pathogens. In particular, the optimisation of dose and application time validation should be performed for a solid conclusion about the competitive ability of MX95, ALPO and AL142PE and the usefulness of potential biological limiters.

Establishment of an Efficient Polyethylene Glycol (PEG)-Mediated Transformation System in Pleurotus eryngii var. ferulae Using Comprehensive Optimization and Multiple Endogenous Promoters

Pleurotus eryngii var. ferulae, a fungus of the genus Pleurotus, efficiently degrades lignin, especially during co-cultivation with other fungi. However, low transformation efficiency and heterologous gene expression restrict systematic studies of the molecular mechanisms and metabolic control of natural products in this mushroom. In this study, the homologous resistance marker carboxin (cbx) was used to establish a polyethylene glycol-mediated transformation (PMT) system in P. eryngii var. ferulae. Optimization of the transformation process greatly improved the number of positive transformants. In particular, we optimized: (i) protoplast preparation and regeneration; (ii) screening methods; and (iii) transformation-promoting factors. The optimized transformation efficiency reached 72.7 CFU/μg, which is higher than the average level of Pleurotus sp. (10–40 CFU/μg). Moreover, three endogenous promoters (Ppfgpd1, Ppfgpd2, and Ppfsar1) were screened and evaluated for different transcription initiation characteristics. A controllable overexpression system was established using these three promoters that satisfied various heterologous gene expression requirements, such as strong or weak, varied, or stable expression levels. This study lays the foundation for recombinant protein expression in P. eryngii var. ferulae and provides a method to investigate the underlying molecular mechanisms and secondary metabolic pathway modifications.

Dietary cerebrosides in seven edible mushrooms: One step detection, quantification, and Si-SPE assisted isolation

Cerebrosides are important high-value dietary molecules with unique biological functions which are found extensively in mushrooms. However, tedious detection/extraction methods and lack of adequate reports led mushrooms to be an under-utilized cerebroside source. In this study, two of glycosphingolipids, cerebrosides B and E were identified and further confirmed from seven edible mushrooms (Pleurotus eryngii, Agaricus bisporus, Hypsizygus marmoreus, Pleurotus ostreatus, Agrocybe aegerita, Flammulina velutipes and Lentinus edodes) by high-resolution tandem mass spectrometry and hydrogen-1/carbon-13 nuclear magnetic resonance. A rapid method using high-performance liquid chromatography coupled with an evaporative light-scattering detector (HPLC-ELSD) was explicitly developed to detect and isolate cerebrosides from edible fungal matrices. The developed method accurately quantified cerebrosides B (0.15–1.05 mg/g, dry matter) and E (0.18–1.80 mg/g, dry matter), thus verified its applicability. Furthermore, silica solid-phase extraction was established to obtain cerebroside-rich extracts from shiitake mushroom (>46 %, peak area %) and was later advanced to semi-preparative HPLC, which led to the isolation of cerebroside molecules (>98 % purity, peak area %). The current work presents a one-step, cost-effective, sensitive HPLC-ELSD method that accurately quantified cerebrosides from edible mushrooms and can be easily adapted for other fungal species.

Biodriven investigation of the wild edible mushroom Pleurotus eryngii revealing unique properties as functional food

• Pleurotus eryngii extract activate the Nrf2 and enhance the antioxidant activity. • N -acetyl tryptamine found in Pleurotus eryngii inhibits acetylcholinesterase. • Pleurotus eryngii contain high level of Zinc and other essential trace elements. • Pleurotus eryngii extract acts on several genes expression, suggesting potential protection against life threatening diseases. Pleurotus eryngii ( P. eryngii ) is largely represented among consumed mushrooms. We conducted an investigation dealing with its antioxidant potential, the presence of essential trace elements and its contribution to the management of brain-related disorders. A bio-guided extraction revealed that one extract was highly effective on activation of the nuclear factor Nrf2, the regulator of the cellular resistance to oxidants. Its analysis revealed the presence of N -acetyltryptamine (NAT), a precursor of the neurotransmitters, melatonin and serotonin. Both extract and NAT, were found as competitive inhibitors of acetylcholinesterase. The essential trace elements analyses showed the presence of high amounts of zinc. RNA-seq technology confirmed upregulates expression of Nrf2 on HepG2 cells and revealed key genes involved in anticholesterolemic, antioxidant effects, cancer and brain disorders. Our study achieved a comprehensive strengthening of the nutritional health-benefit properties of P. eryngii largely used in folk medicines and open perspectives for investigation in food and medicine.

다소비 식품에 대한 비타민 D 함량 분석 다소비 식품에 대한 비타민 D 함량 분석

In the present study, the vitamin D content of frequently-consumed Korean foods were evaluated to update the National Standard Food Composition Table (NSFCT) that is published by the Korean Rural Development Administration. Total 181 types of frequently-consumed foods including cereals, beans, vegetables, meat and, fish products, drinks, condiments, and mushrooms were analyzed by liquid chromatography-mass spectrometry. The standard materials, BCR-122 and SRM 3235, exhibited recovery rates of 98.40% and 104.17%, respectively. All the analyses were performed under the control line based on the quality control chart for vitamin D2 and D3. Among the analysis of 181 species, vitamin D was detected only in 16 species including mushrooms (Vit D2), eggs and fish products (Vit D3). The vitamin D2 content of mushroom ranged from 0 to 147.96 μg/100 g, with naturally dried Sparassis crispa exhibiting the highest vitamin D2 content. In mushroom of Sparassis crispa, Lentinula edoles, Pleurotus eryngii, and Agaricus bisporus the natural drying showed the superior to vitamin D content compared to those of device drying. However, raw mushrooms except for Auricularia auricula-judae did not contain vitamin D2. The vitamin D3 content of eggs and fish products ranged from 0 to 8.90 μg/100 g (solids part in canned salmon). However, vitamin D was not detected in a majority of the frequently-consumed foods under analysis, such as cereals, beans, vegetables, nut and seeds, ginseng, fruits and seaweed, most fish products and animal foods.

Bacterial Community Composition in the Growth Process of Pleurotus eryngii and Growth-Promoting Abilities of Isolated Bacteria.

The effects of biological factors on the vegetative growth process of mushrooms remain largely unexplored. We investigated the bacterial community in different growth stages of Pleurotus eryngii by high-throughput sequencing technology to explore the relationship between interacting bacteria and the growth and development of P. eryngii. We found significant variances in mushroom interacting association bacteria (MIAB) compositions among the samples from different growth stages, and 410 genera were identified. The bacteria in the full-bag and post-ripe stages were shifted to the biocontrol and growth-promotion ones. The mushroom growth-promoting bacteria (MGPB) were also isolated successfully and identified as B. cereus Bac1. The growth speed and density of mycelial pellets of P. eryngii, and activities of two exoenzymes (laccase and amylase), were analyzed by adding the different volumes of cell-free fermentation broth of B. cereus Bac1 to fungal culture media. The results showed that when a 5 mL cell-free fermentation broth was used, the growth speed of P. eryngii hyphae was enhanced by 1.15-fold over the control and reached 0.46 mm/h. The relative activity of laccase and amylase was increased by 26.9 and 43.83%. Our study revealed that the abundant interacting bacteria coexist with P. eryngii hyphae. Moreover, the abundance of some bacteria exhibiting a positive correlation with the growth periods of their host fungi can effectively promote the growth of the host, which will provide technical supports on the high-efficiency production of P. eryngii in factory cultivation.

Rapid detection method of Pleurotus eryngii mycelium based on near infrared spectral characteristics

Edible fungus is a large fungus with edible and medicinal value. Rapid detection of mycelium phenotypic characteristics is of great significance for edible fungus breeding and intelligent cultivation. Traditional method based on experienced observation easily led to make mistakes on distinguishing the growth stages, which impacted on the yield and quality of edible fungus. Therefore, in view of the lack of accurate and efficient detection technology during the growth stages of Pleurotus eryngii mycelium, a rapid detection method of Pleurotus eryngii mycelium at different growth stages is proposed based on the characteristics of near-infrared spectroscopy. First, the spectral data of mycelium of Pleurotus eryngii at six different growth stages were scanned. Second, the multivariate scattering correction method (MSC) was used to pre-process the raw spectral data, and then the competitive adaptive reweighted sampling algorithm (CARS) was adopted to detect the characteristic wave number of the effective variables for Pleurotus eryngii mycelium. In addition, the mathematical model between the mycelium of Pleurotus eryngii and the characteristic wave number of near-infrared spectrum was established by using feed forward neural network (BP). Finally, and the coding vector output by the network was used to detect to the growth stages. The results showed that the BP neural network structure of MSC-CARS-BP detection model was 86–85-85–95-6, and the accuracy of identifying different growth stages of Pleurotus eryngii mycelium was 99.67%. The research results could provide a new idea and technical support for the rapid detection of Pleurotus eryngii mycelium at different growth stages.

Cultivating Pleurotus ostreatus and Pleurotus eryngii mushroom strains on agro-industrial residues in solid-state fermentation. Part II: Effect on productivity and quality of carposomes

The potential of selected Pleurotus ostreatus and P. eryngii wild-type and commercial strains to colonize and produce carposomes after solid-state fermentation of five substrates constituted of agro-residues namely wheat straw (WS), beech wood shavings (BWS), coffee residue (CR), barley and oats straw (BOS), rice bark (RB), supplemented with wheat bran was investigated. The effect of substrate composition on bioprocess feasibility was assessed for the different strains by quantitative (i.e., mushroom yield and Biological Efficiency-BE %) and carposome qualitative parameters (i.e., weight, size, colour, firmness). P. ostreatus strains produced carposomes earlier than P. eryngii ones. Early fruiting formation was promoted in WS for P. ostreatus strains, whereas for P. eryngii the lowest values of earliness were observed on BOS substrate. As for crop productivity, P. ostreatus strain AMRL 150 provided the highest BE (>70%) in all substrates except for RB, while P. ostreatus strain AMRL 144 achieved the highest yield and BE in BOS and BWS (75.30 and 64.26%, respectively). P. eryngii stains produced less number but heavier carposomes. The highest values of BE% for these strains were recorded on WS and BOS substrates. The BE was further correlated to growth parameters of fungal vegetative phase. As for mushroom colour, P. ostreatus were lighter than P. eryngii and BOS substrate promoted lightness in both strains. Firmer P. ostreatus mushrooms were produced at CR. No differences in the whiteness and firmness were detected among P. eryngii mushrooms and at any substrate used. The data included in this paper showed that Pleurotus mushrooms can be cultivated on low- or zero-value agro-industrial residues of great financial and environmental importance towards the production of value-added food products.