Production of Extracellular Enzymes by Lentinula edodes Strains in Solid-State Fermentation on Lignocellulosic Biomass Sterilized by Physical and Chemical Methods.

Two methods of sterilization of lignocellulosic biomass were performed in this study. Eucalypt waste (EW) supplemented with rice bran (RB) was added in the proportions 80:20 and 90:10 in dry weight. The compositions were sterilized by physical method (autoclaving) and by chemical method (H2O2). The production of extracellular enzymes by Lentinula edodes strains was compared within the two methods. Inactivation of catalase present in RB was achieved with 250 mM H2O2. The use of H2O2, when compared by physical method, favored high production of hydrolytic enzymes such as endoglucanase (1,600 IU/kg), twofold higher, ß-glucosidase (1,000 IU/kg), fivefold higher, xylanase (55,000 IU/kg), threefold higher and ß-xylosidase (225 IU/kg), similar results. Oxidative enzymes, MnP and laccase, were produced within a different profile between strains, with shorter times for laccase (2,200 IU/kg) by SJC in 45 days and MnP (2,000 IU/kg) by CCB-514 in 30 days. High production of extracellular enzymes is achieved by the use of the chemical method of sterilization of lignocellulosic biomass; in addition to no energy consumption, this process is carried out in a shorter execution time when compared to the physical process. The use of H2O2 in sterilization does not produce toxic compounds from the degradation of hemicellulose and cellulose such as furfural and hydroxy-methyl-furfural that cause inhibition of microorganisms and enzymes.

LENTINULA EDODES POLYSACCHARIDES SUPPRESSED PRO-INFLAMMATORY CYTOKINES EXPRESSION AND COLITIS IN MICE.

BACKGROUND: Polysaccharides from edible mushrooms possess immunomodulatory, anti-inflammatory, and anti-tumor activities. Recent studies indicated that necroptosis plays a role in the pathogenesis of inflammatory diseases and mediates increased expression of inflammatory cytokines. OBJECTIVE: Therefore, it is imperative to determine the impact of polysaccharide extract from Lentinula edodes (L. edodes) on inflammatory cytokines in experimental model of colitis in mice. METHODS: Female C57BL/6 mice divided into three or four mice per group were used for this study. Polysaccharide sample was orally administered to mice prior to (7 days) and during colitis induction with 2.5% dextran sodium sulfate (7 days), followed by additional 3 days of administration. Changes in body weight and colon length were used as markers for colitis, and pro-inflammatory cytokines and tumor necrosis factor receptor 1 (TNFR1) expressions, as well as necroptosis were analyzed in the colon of colitis mice. Data obtained were analysed by Tukey-Kramer and two-tailed standard t tests. RESULTS: The results indicated that the polysaccharide sample suppressed colitis in mice using effects on the body weight and colon length as markers. Also, it was demonstrated that necrostatin-1, a specific inhibitor of necroptosis, suppressed the expression of interleukin (IL)-8, a pro-inflammatory chemokine, in Caco-2 cells induced necroptosis induced by zVAD and TNF-α, an indication that necroptosis may be involved in the expression of pro-inflammatory cytokines. Moreover, the polysaccharide sample suppressed the expression of pro-inflammatory cytokines such as tumor necrosis factor (TNF)-α, IL-6, IL-1ß, and interferon (IFN)-γ in the colon of mice. CONCLUSION: These results suggested that the suppressive effects of the polysaccharide sample on inflammatory cytokines expression may contribute to its anti-colitis effect, and so may serve as a potent therapeutic agent against inflammatory bowel disease.

Shiitake Culinary-Medicinal Mushroom, Lentinus edodes (Agaricomycetes): Absence of Changes in Maternal Reproductive Performance and Embryofetal Development In Vivo.

The shiitake culinary-medicinal mushroom Lentinus edodes (=Lentinula edodes) has been used as a nutritional complement. This study evaluated, through reprotox tests, the consumption of L. edodes in pregnant rats, considering it as a functional food. Pregnant rats were daily exposed to L. edodes before implantation (LeB)-from 1 to 19 days of gestation, and after implantation (LeA)-from 9 to 19 days of gestation, compared with controls. On the 20th day of gestation, cesarean sections were performed. Blood was collected and hematological parameters (hemoglobin, hematocrit, white and red blood cells and platelets) were analyzed. Moreover, albumin, calcium, creatine kinase, alkaline phosphatase, transferases, creatinine, urea, triglycerides, cholesterol, lipase, glucose, and insulin were assessed in serum. Organs were collected and weighed, and the fetuses were analyzed morphologically by body measurements. The consumption of L. edodes reduced triglycerides levels and there were no changes in maternal weight, biochemical and hematological parameters, organ weight, and reproductive capacity. There were no morphological changes in the fetuses' body measurements, suggesting possible safety in ingestion of mushroom. Reprotox tests used to evaluate the daily consumption of L. edodes points out potentiality as a functional food, suggesting safety during the gestational period.

Bioavailability of Compounds Susceptible to Enzymatic Oxidation Enhances Growth of Shiitake Medicinal Mushroom (Lentinus edodes) in Solid-State Fermentation with Vineyard Prunings.

Grapes are widely produced in northwestern Mexico, generating many wood trimmings (vineyard prunings) that have no further local use. This makes vineyard prunings a very attractive alternative for the cultivation of white-rot medicinal mushrooms such as Lentinus edodes. This type of wood can also offer a model for the evaluation of oxidative enzyme production during the fermentation process. We tested the effect of wood from vineyard prunings on the vegetative growth of and production of ligninolytic enzymes in L. edodes in solid-state fermentation and with wheat straw as the control substrate. The specific growth rate of the fungus was 2-fold higher on vineyard pruning culture (µM = 0.95 day-1) than on wheat straw culture (µM = 0.47 day-1). Laccase-specific production was 4 times higher in the vineyard prunings culture than on wheat straw (0.34 and 0.08 mU · mg protein-1 · ppm CO2-1, respectively), and manganese peroxidase production was 3.7 times higher on wheat straw culture than on vineyard prunings (2.21 and 0.60 mU · mg protein-1 · ppm CO2-1, respectively). To explain accurately these differences in growth and ligninolytic enzyme activity, methanol extracts were obtained from each substrate and characterized. Resveratrol and catechins were the main compounds identified in vineyard prunings, whereas epigallocatechin was the only one detected in wheat straw. Compounds susceptible to enzymatic oxidation are more bioavailable in vineyard prunings than in wheat straw, and thus the highest L. edodes growth rate is associated with the presence of these compounds.

Productivity, Physicochemical Changes, and Antioxidant Activity of Shiitake Culinary-Medicinal Mushroom Lentinus edodes (Agaricomycetes) Cultivated on Lignocellulosic Residues.

The effects of substrate and strain on productivity, physicochemical characteristics, and compounds with antioxidant activity were evaluated in basidiomes of the shiitake mushroom, Lentinus edodes. Strains IE-245 and IE-256 and the substrates oak wood shavings (OW), sorghum stubble (SS), and sugar cane bagasse (SC) were used. Productivity was evaluated by measuring biological efficiency (BE), production rate (PR), and yield. Total sugars, total soluble solids, pH, titratable acidity, color parameters, total phenolics, flavonoids, ascorbic acid, and antioxidant activity of the basidiomes were measured. BE, PR and yield were higher with the combination IE-256/SS, at 103.71%, 1.32%, and 34.57%, respectively. The largest amount of total sugars (17.61 mg glucose · g-1 dry weight) was found with combination IE-256/SS. Variation was observed in basidiome color; the lowest luminosity (L*) value (darkest color) was found in the IE-256 strain on the OW substrate (L* = 30.45), whereas that of the IE-245 strain on the SC substrate was the lightest in color (L* = 57.00). The largest amounts of total phenolics were recorded in the IE-256 strain on the OW (6.50 mg gallic acid equivalents [GAE] · g-1 dry weight) and the SS substrates (5.85 mg GAE · g-1 dry weight). The best antioxidant activity was obtained with IE-256-0.80, 0.65, and 0.59 µmol Trolox equivalents · g dry weight-1-on the OW, SC, and SS substrates, respectively. Based on the values of BE, PR, and yield, IE-256/SS was the most productive. Substrate and strain, and their interactions, influenced the physicochemical characteristics of the basidiomes and the amounts of compounds with antioxidant activity they contained.

Undergraduate dental sudents' perspectives about experiences in primary care for their education in the field of health / Perspectivas de graduandos em odontologia acerca das experiências na atenção básica para sua formação em saúde

Supervised training periods in primary care have been used as spaces for teaching and extension in the area of health, making it feasible to include undergraduates in concrete teaching-learning scenarios. The aim of this study was to analyze the perceptions of dental students about the importance of supervised training periods in Family Health Units to their professional education. The sample consisted of 185 students who answered the question: What is your opinion about the importance of this training period in SUS to your professional education? Comment on this experience and its positive and negative aspects The responses were analyzed by the quali-quantitative Collective Subject Discourse (CSD) technique. The students appreciated learning through practice in the service; contact with professionals from other areas; opportunity for technical-operative improvement and demonstrated sensitivity in the face of social reality, although they appeared to be concerned about being absent from the faculty, arguing that they were being prejudiced as regards their intramural clinical productivity, exhaustively demanded of them. It was concluded that students placed value on the extramural experience, however, it was perceived that there was still a predominant influence of focus on intramural clinical training.

Os estágios supervisionados na atenção básica vêm sendo utilizados como espaços de ensino e extensão nas áreas da saúde, viabilizando a inserção dos graduandos em cenários concretos de ensino-aprendizagem. O objetivo deste estudo foi analisar as percepções de acadêmicos de odontologia sobre a importância do estágio supervisionado em Unidades de Saúde da Família, para sua formação profissional. A amostra foi constituída por 184 acadêmicos que responderam à questão: Qual a sua opinião em relação à importância deste estágio no SUS para a sua formação profissional? Comente esta experiência e seus aspectos positivos e negativos. As respostas foram analisadas através da técnica qualiquantitativa do discurso do sujeito coletivo. Os alunos valorizaram o aprendizado através da prática no serviço, do contato com profissionais de outras áreas, da oportunidade de aperfeiçoamento técnico-operatório e demonstraram sensibilização frente à realidade social, embora tenham aparentado incômodo por se ausentarem da faculdade, sob o argumento de serem prejudicados quanto à produtividade da clínica intramuros, exaustivamente cobrada. Concluiu-se que os alunos valorizaram a experiência extramural, entretanto, percebeu-se que ainda há uma hegemonia do foco no treinamento clínico intramuros.

Biosorption potential of synthetic dyes by heat-inactivated and live Lentinus edodes CCB-42 immobilized in loofa sponges.

Lentinus edodes CCB-42 was immobilized in loofa sponges and applied to the biosorption of the synthetic dyes congo red, bordeaux red and methyl violet. Live immobilized microorganisms achieved average decolorations of congo red, bordeaux red and methyl violet of 97.8, 99.7 and 90.6 %, respectively. The loofa sponge was the support and the coadjuvant promoting dye adsorption. The biosorption conditions were optimized for each dye, yielding 30 °C, pH 5.0 and a 12 h reaction time for congo red; 25 °C, pH 3.0 and 36 h for bordeaux red; and 25 °C, pH 8.0 and 24 h for methyl violet. Operational stability was evaluated over five consecutive cycles, with both bordeaux red and congo red exhibiting decolorations above 90 %, while the decoloration of methyl violet decreased after the third cycle. In the sixth month of storage, congo red, bordeaux red and methyl violet had decolorations of 93.1, 79.4 and 73.8 %, respectively. Biosorption process best fit the pseudo-second-order kinetic and Freundlich isotherm models. Maximum biosorption capacity of heat-treated L. edodes immobilized in loofa sponge was determined as 143.678, 500.00 and 381.679 mg/g for congo red, bordeaux red and methyl violet, respectively. Treatment with immobilized L. edodes reduced the phytotoxicity of the medium containing dyes. FT-Raman experiments suggested the occurrence of interactions between loofa sponge fibers, L. edodes and dye. L. edodes CCB-42 immobilized in loofa sponges represents a promising new mode of treatment of industrial effluents.

Improvement of yield of the edible and medicinal mushroom Lentinula edodes on wheat straw by use of supplemented spawn.

The research evaluated the interactions of two main factors (strain / types of spawn) on various parameters with the purpose to assess its effect on yield and biochemical composition of Lentinula edodes fruiting bodies cultivated on pasteurized wheat straw. The evaluation was made with four strains (IE-40, IE-105, IE-124 and IE-256). Different types of spawns were prepared: Control (C) (millet seed, 100%), F1 (millet seed, 88.5%; wheat bran, 8.8%; peat moss, 1.3%; and CaS04, 1.3%) and F2 (the same formula as F1, but substituting the wheat bran with powdered wheat straw). Wheat straw was pasteurized by soaking it for 1 h in water heated to 65 °C. After this the substrate (2 kg wet weight) was placed in polypropylene bags. The bags were inoculated with each spawn (5% w/w) and incubated in a dark room at 25 °C. A proximate analysis of mature fruiting bodies was conducted. The mean Biological Efficiency (BE) varied between 66.0% (C-IE-256) and 320.1% (F1-IE-124), with an average per strain of 125.6%. The highest mean BE was observed on spawn F1 (188.3%), significantly different from C and F2. The protein content of fruiting bodies was high, particularly in strain IE-40-F1 (17.7%). The amount of fat varied from 1.1 (F1-IE-40) to 2.1% (F2-IE-105) on dry matter. Carbohydrates ranged from 58.8% (F1-IE-40) to 66.1% (F1-IE-256). The energy value determined ranged from 302.9 kcal (F1-IE-40) to 332.0 kcal (F1-IE-256). The variability on BE observed in this study was significantly influenced by the spawn's formulation and genetic factors of the different strains.

Improvement of yield of the edible and medicinal mushroom Lentinula edodes on wheat straw by use of supplemented spawn

The research evaluated the interactions of two main factors (strain / types of spawn) on various parameters with the purpose to assess its effect on yield and biochemical composition of Lentinula edodes fruiting bodies cultivated on pasteurized wheat straw. The evaluation was made with four strains (IE-40, IE-105, IE-124 and IE-256). Different types of spawns were prepared: Control (C) (millet seed, 100%), F1 (millet seed, 88.5%; wheat bran, 8.8%; peat moss, 1.3%; and CaS0(4), 1.3%) and F2 (the same formula as F1, but substituting the wheat bran with powdered wheat straw). Wheat straw was pasteurized by soaking it for 1 h in water heated to 65 °C. After this the substrate (2 kg wet weight) was placed in polypropylene bags. The bags were inoculated with each spawn (5% w/w) and incubated in a dark room at 25 °C. A proximate analysis of mature fruiting bodies was conducted. The mean Biological Efficiency (BE) varied between 66.0% (C-IE-256) and 320.1% (F1-IE-124), with an average per strain of 125.6%. The highest mean BE was observed on spawn F1 (188.3%), significantly different from C and F2. The protein content of fruiting bodies was high, particularly in strain IE-40-F1 (17.7%). The amount of fat varied from 1.1 (F1-IE-40) to 2.1% (F2-IE-105) on dry matter. Carbohydrates ranged from 58.8% (F1-IE-40) to 66.1% (F1-IE-256). The energy value determined ranged from 302.9 kcal (F1-IE-40) to 332.0 kcal (F1-IE-256). The variability on BE observed in this study was significantly influenced by the spawn's formulation and genetic factors of the different strains.

Improvement of yield of the edible and medicinal mushroom Lentinula edodes on wheat straw by use of supplemented spawn

The research evaluated the interactions of two main factors (strain / types of spawn) on various parameters with the purpose to assess its effect on yield and biochemical composition of Lentinula edodes fruiting bodies cultivated on pasteurized wheat straw. The evaluation was made with four strains (IE-40, IE-105, IE-124 and IE-256). Different types of spawns were prepared: Control (C) (millet seed, 100%), F1 (millet seed, 88.5%; wheat bran, 8.8%; peat moss, 1.3%; and CaS0(4), 1.3%) and F2 (the same formula as F1, but substituting the wheat bran with powdered wheat straw). Wheat straw was pasteurized by soaking it for 1 h in water heated to 65 °C. After this the substrate (2 kg wet weight) was placed in polypropylene bags. The bags were inoculated with each spawn (5% w/w) and incubated in a dark room at 25 °C. A proximate analysis of mature fruiting bodies was conducted. The mean Biological Efficiency (BE) varied between 66.0% (C-IE-256) and 320.1% (F1-IE-124), with an average per strain of 125.6%. The highest mean BE was observed on spawn F1 (188.3%), significantly different from C and F2. The protein content of fruiting bodies was high, particularly in strain IE-40-F1 (17.7%). The amount of fat varied from 1.1 (F1-IE-40) to 2.1% (F2-IE-105) on dry matter. Carbohydrates ranged from 58.8% (F1-IE-40) to 66.1% (F1-IE-256). The energy value determined ranged from 302.9 kcal (F1-IE-40) to 332.0 kcal (F1-IE-256). The variability on BE observed in this study was significantly influenced by the spawn's formulation and genetic factors of the different strains.

Use of spent mushroom substrates from Agaricus subrufescens (syn. A. blazei, A. brasiliensis) and Lentinula edodes productions in the enrichment of a soil-based potting media for lettuce (Lactuca sativa) cultivation: Growth promotion and soil bioremediation.

This study aimed to assess physicochemical and microbiological properties of fresh spent mushroom substrates (SMSs)--without post-crop heat treatment--from Agaricus subrufescens and Lentinula edodes production to optimize the use of these residues in the soil enrichment for lettuce growth promotion and soil remediation. Organic matter and C content of both SMSs were high. Fresh A. subrufescens SMS was a good source of N, P and K. On the other hand, L. edodes SMS presented a lower concentration of these nutrients and a high level of immaturity. Both SMSs presented high electric conductivity values (2.5-3.4 mS/cm). Microbiological analysis, based upon enumeration of culturable bacteria (thermophilic and mesophilic) and fungi, and also evolution of CO(2), showed that SMSs played higher microbial diversity than soil control. Laccase activity from A. subrufescens SMS tended to remain constant during a 2-month period, while L. edodes SMS presented low laccase activity throughout the same period. Agaricus subrufescens and L. edodes were able to grow on a PDA (Potato Dextrose Agar) media supplemented with different concentrations of atrazine (1-50 microg/ml), degraded the herbicide, attaining rates of 35% and 26%, respectively. On experiments of lettuce growth promotion using a soil-based potting media with different SMS rates, 5% and 10% (dw) rates of A. subrufescens SMS resulted in higher lettuce aerial dry weights than the rates of 25% and 40%, the chemical fertilization (NPK) and the control (soil). At 10% supplementation, lettuce aerial dry weight increased 2.2 and 1.3 times compared to the control and the NPK treatment, respectively. Protein content increased along with SMS rates. Fresh A. subrufescens SMS was an excellent supplement for lettuce growth promotion and showed potential for remediation of biocides possibly due to improved microbial diversity and enzymatic activity. Fresh L. edodes SMS was not a good fertilizer, at least under the conditions tested. However, microbiological analysis showed that promising results may be achieved when using fresh L. edodes SMS for soil remediation.

Biotreatment of an effluent from a wood laminate industry using Lentinula edodes UEC 2019.

The aim of this work was to evaluate the performance of the fungus Lentinula edodes UEC 2019 in the treatment of an effluent derived from a wood laminate manufacturing process. The factorial design methodology was employed to verify the influence of the source of nitrogen, co-substratum and treatment time variables on the color and total phenols reduction. Assays were conducted in Erlenmeyer flasks and bench bioreactor and the obtained results showed that the best conditions for the effluent remediation were observed when using the effluent itself as the nitrogen source (1g/L) and glucose (79 g/L) as co-substratum (glucose) during a treatment period of 30 days. It was possible the remove 92% phenol, 97% color and reduce the COD in the bioreactor by 99% while controlling the temperature, pH and feeding. These results demonstrate that the fungus was able to use the effluent components as substrate and that it has potential for use in wood lamination effluent remediation.

Bioconversion of agrowastes by Lentinula edodes: the high potential of viticulture residues.

The production of four strains of edible mushroom Lentinula edodes was evaluated through solid-state fermentation (SSF) of vineyard pruning (VP), barley straw (BS), and wheat straw (WS). Biological efficiency, proximal composition, and energy value of the fruiting bodies, as well as substrate chemical changes after harvest, were determined. The shortest primordium formation time (28 days), highest biological efficiency (93.25%), highest yield (37.46%), and shortest production cycle (6 days) were observed in VP. The fruiting bodies obtained from VP had high energy value (379.09 to 392.95 kcal) and contents of protein (12.37 to 17.19%), but low contents of fat (1.82 to 2.15%). After SSF, phenol concentration decreased on VP (1.2 mmol/L) and BS (0.31 mmol/L), but on WS remained practically the same. Hemicellulose decreased in all substrates; cellulose increased on WS and decreased in the rest of the treatments. Lignin decreased on WS and BS, but its concentration increased on VP. The variability observed in the degradation capacity of lignocellulosic components was influenced by the substrate's nature, environmental factors, and genetic factors among strains. VP has great potential for shiitake production due to its low cost, short production cycles, and high biological efficiency.

Effect of cereal brans on Lentinula edodes growth and enzyme activities during cultivation on forestry waste.

AIMS: To develop strategies for increasing the growth of Lentinula edodes in eucalyptus residues. To this end, we have examined the effects of cereal brans additions on production of mycelial biomass and enzymes. METHODS AND RESULTS: Three isolates of the mushroom shiitake, L. edodes (Berk. Pegler), were evaluated for enzyme and ergosterol production on eucalyptus residue supplemented with 5, 10, 15 and 20% (w/w) of soya, wheat or rice brans. Nitrogen imput on eucalyptus residues accelerated mycelial growth by supplying the L. edodes with this limiting nutrient. High levels of enzymes activities were produced in eucalyptus residues supplemented by soya bran. Comparison of cellulose and xylanase production with manganese peroxidase (MnP) at 20% soya bran indicated that hydrolytic enzymes, but oxidative enzymes were reduced. CONCLUSIONS: Mycelial growth measurements revealed that eucalyptus residues supplemented with cereal brans supported fast growth of L. edodes, indicating that mycelium extension is related to the bioavailability of nitrogen. The type and concentration of nutrient supplement has a considerable effect both on substrate colonization and on the type of hydrolytic and oxidative enzymes produced. These characteristics may be useful for mushroom growing. SIGNIFICANCE AND IMPACT OF THE STUDY: Lentinula edodes is commercially important for edible mushroom production and supplements which enhance growth and enzymes production might also be beneficial for mushroom yields.

Decolorization of synthetic dyes by solid state cultures of Lentinula (Lentinus) edodes producing manganese peroxidase as the main ligninolytic enzyme.

The ability of the white-rot fungus Lentinula (Lentinus) edodes to decolorize several synthetic dyes was investigated using solid state cultures with corn cob as substrate. Cultures, containing amido black, congo red, trypan blue, methyl green, remazol brilliant blue R, methyl violet, ethyl violet and Poly R478 at 200 ppm, were completely decolorized after 18 days of incubation. Partial decolorization was observed in the cultures containing 200 ppm of brilliant cresyl blue and methylene blue. High manganese peroxidase activity (2600 U/g substrate), but very low lignin peroxidase (<10 U/g substrate) and laccase (<16 U/g substrate) activities were detected in the cultures. In vitro, the dye decolorization was markedly decreased by the absence of manganic ions and H2O2. These data suggest that manganese peroxidase appear to be the main responsible for the capability of L. edodes to decolorize synthetic dyes.

Biodecolorization screening of synthetic dyes by four white-rot fungi in a solid medium: possible role of siderophores.

AIMS: Four selected fungi were screened for their ability to decolourize a textile effluent and commercial reactive dyes in a solid medium. METHODS AND RESULTS: Ligninolytic enzymes activities (lignin peroxidase, manganese peroxidase and laccase) and siderophores presence were monitored in decolourized plates. RESULTS: The results showed low lignin peroxidase activity and no manganese peroxidase activity was detected for all fungi. Laccase activity was observed in Reactive Blue 19 decolourized plates by Trametes versicolor and Trametes villosa. Siderophores presence was observed in Trametes versicolor, Phanerochaete chrysosporium and Lentinus edodes decolourized plates. CONCLUSION: Lentinus edodes displayed the greatest decolourization ability both in terms of extent and rapidity of decolourization. SIGNIFICANCE AND IMPACT OF THE STUDY: The transformation observed for dyes open the possibility to study siderophores to treat dyes and textile effluents.