RESUMO

An edible Mushroom-Nafion modified glassy carbon electrode (M2N5-GCE) was prepared using a homogeneous mixture varying the concentrations of these, in addition to the origin of the mushroom (Shiitake, Lentinula edodes, M1 and Abrantes, Agariscus bisporus, M2) and applied to the As(III) determination by anodic stripping voltammetry. After choosing the optimal conditions in the preparation of the electrode, the second stage was to study the effects of various parameters such as supporting electrolyte, pH, accumulation potential, and time (Eacc, tacc). The optimum experimental conditions chosen were Britton Robinson buffer 0.01 mol L-1 pH:4.6; Eacc: -1.0 and tacc: 60 s obtaining a signal of oxidation of As(0) to As(III) about 0.08 V. Peak current was proportional to arsenic concentration over the 19.6-117.6 µg L-1 range, with a 3σ detection limit of 13.4 µg L-1. The method was validated using As(III) spiked tap water from the laboratory with satisfactory results (RE:3.0 %). Finally, the method was applied to the determination of As(III) in water samples from the Loa River (Northern Chile) in the presence of As(V) in a concentration >20 times higher (RE: 2.3 %).

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RESUMO

Lentinula edodes is known to show high nutritional and organoleptic properties and can be mixed with different by-products in the production of new foods with important functional characteristics. Cocoa pod husk (CPH) is the main by-product in the cocoa industry and presents important bioactivities. In this research, two mixtures were applied based on Lentinula edodes mushroom flour from fifty different strains (strain 1 to strain 50) and cocoa pod husk flour (CPHF): 60% Lentinula edodes mushroom flour from each strain mixed with 40% CPHF (Mixture 1), and 80% Lentinula edodes mushroom flour from each strain mixed with 20% CPHF (Mixture 2). The parameters evaluated were moisture, proteins, fat, total dietary fiber (TDF), ash, carbohydrates, antioxidant capacity, antimicrobial activity, pH and water activity (aw). The multivariate statistical techniques evaluated those samples that exhibited the highest degree of correlation with the distinct chemical and commercial parameters, showing that sample 13 of both mixture flours (M1 and M2) obtained by the mushrooms of L. edodes (strain 13) with CPH indicated the higher significant of the parameters. In addition, the sensory test of the best flour (sample 13) was applied to 50 panelists, presenting the best sensory characteristics, such as color, aroma, texture and general acceptability.

RESUMO

The fruiting bodies of edible mushrooms represent an important source of biologically active polysaccharides. In this study, Lentinula edodes crude polysaccharides (LECP) were extracted in hot water, and their antioxidant and antiradical activities were investigated. The antioxidant activity of LECP was investigated against reactive species such as 1,1'-diphenyl-2-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid, hydroxyl and superoxide anion radicals, reducing power with EC50 values of 0.51, 0.52, 2.19, 3.59 and 1.73 mg/mL, respectively. Likewise, LECP inhibited the lipid peroxidation induced in methyl linoleate through the formation of conjugated diene hydroperoxide and malondialdehyde. The main sugar composition of LECP includes mannose, galactose, glucose, fucose and glucuronic acid. Characterization by Fourier transform infrared spectroscopy and nuclear magnetic resonance determined that LECP was made up of α and ß glycosidic bonds with a backbone of α-D-Glc, →6)-ß-D-Glcp-(1→, →6)-α-D-Galp-(1→ and ß-D-Manp-(1→ residues. The results showed that LECP can scavenge all reactive species tested in a concentration-dependent manner and with a protective effect in the initial and final stages of lipid peroxidation. The natural antioxidant activity of the LECP that was investigated strengthens the high medicinal and nutritional value of this mushroom.

RESUMO

Agricultural waste products can be used as biosorbents for bioremediation once they are low-cost and high-efficient in pollutants removal. Thus, waste products from mushroom farming such as cutting and substrate of Lentinula edodes (popularly known as shiitake) and Agaricus bisporus (also known as champignon) were evaluated as biosorbents for metallic contaminants copper (Cu) and lead (Pb). Shiitake and champignon stalks, and shiitake substrate (medium in which shiitake was cultivated) were dried, grounded, characterized and experimented to remove Cu and Pb from contaminated water. The Sips model was used to establish the adsorption isotherms. Regarding Cu, champignon stalks have the best removal efficiency (43%), followed by substrate and stalks of shiitake (37 and 30%, respectively). Pb removals were similar among three residues (from 72 to 83%), with the champignon stalks standing out. The maximum adsorption capacities (qmax) for Cu in shiitake and champignon stalks were 22.7 and 31.4 mg/g-1, respectively. For Pb, qmax for shiitake and champignon stalks, and shiitake substrate were 130.0, 87.0 and 84.0 mg/g-1, respectively. The surface morphology of the champignon stalks revealed an organized and continuous structure. After an interaction with metals, the stalk of champignon accumulated the metal ions into interstices. Mushroom residues showed a relevant adsorption efficiency, especially for Pb. Mushroom farming waste are a very low-cost and promising alternative for removing toxic heavy metals from aquatic environment.

RESUMO

During the previous decades, the indiscriminate use of anthelmintics for the control of gastrointestinal nematodes has generated anthelmintic resistance in different parts of the world. It is necessary to search for new sustainable control alternatives, such as the use of extracts from plants and edible mushrooms. Therefore, the aim of the present study was to evaluate the nematicidal activity of extracts and fractions of the edible mushroom Lentinula edodes against Haemonchus contortus eggs and infective larvae. The basidiomata of L. edodes ECS-401 were provided by the Tropical Fungi Laboratory of El Colegio de la Frontera Sur and were extracted with ethyl acetate, methanol, and water. Fractionation of the most active extract was carried out by open column chromatography. The bioassays were performed in 96-well microtiter plates using 100 eggs/larvae, a final volume of 100 µL, and different concentrations of extracts/fractions (n = 4). Bioassay readings were taken at 48 h for egg hatching inhibition (EHI) and at 24, 48 and 72 h for larval mortality (LM). The ethyl acetate extract exhibited the highest percentage of EHI (100%). For the LM bioassay, the aqueous extract was the most active (69%), but its fractions did not show larvicidal activity. The chemical profile of the aqueous extract was analyzed by high-performance liquid chromatography, which showed the presence of phenols, flavonoids, and terpenes. L. edodes extracts showed ovicidal and/or larvicidal activity.

Assuntos

RESUMO

Residues from pharmaceutical products are found in effluents and in other environmental matrices such as soil and surface waters. Chitin and chitosan are highly adsorptive substances present in mushrooms such as champignon (Agaricus bisporus) and shiitake (Lentinula edodes). This study evaluated the adsorption efficiency of shiitake and champignon stalks, and shiitake substrate in water contaminated with paracetamol and 17 α-ethynyl estradiol (EE2). Stalks and substrate were dried and ground. Particles were physically evaluated and chemically characterized. Adsorption kinetic and isotherms were carried out for EE2 and paracetamol. Shiitake and champignon stalks had high percentage of porosity, closed and open pores. All bioproducts from mushroom had chemical groups similar to chitosan standard. However, the degree of deacetylation of chitosan was higher in shiitake (28.3%). In EE2 adsorption kinetics, shiitake and champignon stalks showed 100% removal in 20 and 30 min, respectively. Shiitake substrate showed 80% removal. In paracetamol adsorption kinetics, all bioproducts presented more than 95% removal. In EE2 adsorption isotherm, the maximum adsorption capacities (qmax) to shiitake and champignon stalks and shiitake substrate were 5.62, 18.95 and 0.31 mgEE2/g, respectively. For paracetamol adsorption isotherm, qmax to shiitake and champignon stalks were 34.20 and 338.08 mgparacetamol/g, respectively. In conclusion, shiitake and champignon stalks (specially champignon) had the best results regarding the adsorption of EE2 and paracetamol. Reuse of discarded mushroom waste reduces the environmental impact and can add value to the product.

Assuntos

RESUMO

PURPOSE: Functional foods can prevent/reduce the risks related to obesity. Lentinula edodes is a highly nutritious mushroom rich in protein, vitamins and minerals. Some studies have demonstrated the hypocholesterolemic effects from L. edodes in high doses, which does not represent the consumption in humans. We evaluated ingestion of a realistic dose of L. edodes associated with a high-fat diet (HFD) on hematologic, biochemical and oxidative stress parameters. METHODS: Eighteen male Wistar rats were divided into three groups: control (normal diet); HFD; and HFD + L. edodes (100 mg/kg/day). After 30 days, blood was collected. Biochemical and hematologic parameters were analyzed, as well as oxidative stress biomarkers. RESULTS: The HFD increased levels of total cholesterol and triglycerides. Lentinula edodes reduced these parameters significantly to concentrations found in the control group. The HFD increased levels of alanine transaminase and aspartate transaminase (markers of liver damage). Lentinula edodes returned the levels of these enzymes to normal levels and normalized serum levels of urea (which were also increased owing to consumption of the HFD). Lentinula edodes reduced levels of urea and glucose. Lipid peroxidation was increased in rats receiving the HFD, and L. edodes reduced malondialdehyde levels, thereby preventing oxidation of fatty acids. CONCLUSIONS: Lentinula edodes was shown to have hypolipidemic, hypoglycemic, hepatoprotective and renoprotective features in doses that are suitable for humans.

Assuntos

RESUMO

Shiitake mushroom consumption is increasing in Brazil. In addition to the implementation of new production methods, it is also important to increase productivity, quality and reduce production costs. In this study, six commercial Lentinula edodes strains were characterized for genetic diversity (rep-PCR analysis) and mushroom production (yield, number and weight of individual mushrooms) using different substrates and cultural conditions. All strains showed genetic differences by repetitive element palindromic based-polymerase chain reaction (rep-PCR). The richest substrate resulted in the greatest production under both environmental conditions. Strains LE4 and LE6 produced the majority of their mushrooms earlier than the other strains. The highest number of mushrooms was observed in the LE6 strain while the highest weights of individual mushrooms were observed in the LE4 strain. Controlled environmental conditions resulted in superior production for all strains, except for LE4, which had empirically greater yield in the semi-controlled environmental condition.

Assuntos

RESUMO

The contamination of water resources by metallic ions is a serious risk to public health and the environment. Therefore, a great emphasis has been given to alternative biosorption methods that are based on the retention of aqueous-solution pollutants; in the last decades, several agricultural residues have been explored as low-cost adsorbent. In this study, the ability of Pb (II) biosorption using sugarcane bagasse modified by different fungal species was evaluated. The presence of carbonyl, hydroxyl, and carboxyl groups in the biosorbent was observed by spectroscopy in the infrared region. By scanning electron microscopy, changes in the morphology of modified material surfaces were observed. The highest adsorption capacity occurred at pH 5.0, while the shorter adsorbate-adsorbent equilibrium was at 20 min, and the system followed the pseudo-second-order model. The maximum biosorption in isotherms was found at 58.34 mg g(-1) for modified residue by Pleurotus ostreatus U2-11, and the system followed the Langmuir isotherm. The biosorption process was energetically spontaneous with low desorption values. This modification showed great potential for filters to remove Pb (II) and provide the preservation of water resources and animal health.

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RESUMO

AbstractThe biodiversity rich state of Meghalaya, India located in the realms of mega-biodiversity hotspots, is home to numerous species of wild edible macrofungi that are used extensively by the mycophillic ethnic population, as a part of their traditional cuisine and medicine systems. However, habitat loss, due to deforestation and climate change, is destroying the natural population of these mushrooms, depleting their availability to the local communities. In the present investigation, a GIS guided habitat search, using Lentinula edodes as a representative species, was used in mapping the habitats of wild edible macrofungi of the study region. Sampling of around 4 000 specimens per distinct morphological type available in the traditional markets and "sacred grove" forests indicated presence of ten common genera, belonging to nine different families of wild edible mushrooms. Nutritional profiling of the representative species Lentinula edodes was carried out by evaluation of its moisture, total fat, crude protein and carbohydrates contents by standard methods. Similarly, bioactive components determination was performed by estimation of total phenols, flavonoids, ascorbic acid, β-carotene and lycopenes. Bioactivity of the mushrooms extracts was studied using the DPPH radical scavenging and Human Red Blood Cell (HRBC) membrane stabilization assays. The present investigation successfully attempted to explore remote sensing technologies and GIS (Geographic Information System) based system to predict the natural habitats of wild edible mushrooms of Meghalaya, India which we believe will lead to the generation of a mushroom specific non-wood forest resource mapping system in the near future. Results of nutritional profiling and biological activity studies on the representative species of wild edible mushrooms from the studied region revealed that it is a rich source of essential nutrients and antioxidants.

ResumenLa rica biodiversidad del estado de Meghalaya, India situado en los reinos de los hotspots mega-biodiversidad es el hogar de numerosas especies de macro hongos silvestres comestibles que se utilizan ampliamente por la población étnica micofílica como parte de su alimentación y medicina tradicional. Sin embargo, la pérdida de hábitat debido a la deforestación y el cambio climático está destruyendo la población natural de estos hongos, que agotan su disponibilidad para las poblaciones locales. En la presente investigación, se utilizó el SIG para la búsqueda guiada de hábitat usando Lentinula edodes como especie representativa en la cartografía de los hábitats de macrohongos silvestres comestibles de la región de estudio. Alrededor de cuatro mil ejemplares de distinto tipo morfológico fueron muestreados según su disponibilidad en los mercados tradicionales y los "sacred grove" (bosques sagrados) lo que indicó la presencia de diez géneros comunes pertenecientes a nueve familias de setas silvestres comestibles. Perfiles nutricionales de las especies representativas Lentinula edodes se llevaron a cabo mediante la evaluación de su humedad, grasa total, proteína cruda y contenido de carbohidratos. Del mismo modo, la determinación de componentes bioactivos se realizó por estimación de fenoles totales, flavonoides, ácido ascórbico, β-caroteno y licopeno. La bioactividad de los extractos de setas se estudió mediante la captación de radicales DPPH y el ensayo de estabilización de la membrana de glóbulos rojos de la sangre humana (hRBC). Los resultados de estudios de perfiles nutricionales y actividad biológica en hongos comestibles revelan que es una fuente rica en nutrientes esenciales y antioxidantes. La presente investigación ha intentado con éxito explorar las tecnologías de teledetección y SIG (Sistema de Información Geográfica) para predecir el hábitat natural de los hongos silvestres comestibles de Meghalaya, India que creemos dará lugar a la generación de un mapeo de los recursos forestales no madereros, específicamente de hongos, en el futuro cercano.

Assuntos

RESUMO

Mushroom Lentinula edodes has been widely studied therapeutically. However, there is no data regarding its daily intake level safety. Since L. edodes has many active compounds known to bind to metals, we evaluated macro and micronutrients in liver and kidney of healthy rats after subchronic exposure to L. edodes. Rats were divided into four groups, receiving water and L. edodes at 100, 400 and 800 mg/kg/day. The treatment lasted 30 days. Essential elements (Zn, Cu, Mg, Fe, Mn, Se, Co, Mo, and Li) were analyzed in an inductively coupled plasma mass spectrometer. Our results demonstrated a significant decrease in Cu, Fe, Mn and Co levels in liver of rats receiving L. edodes at the highest doses. In kidney, Mn, Mo and Li concentrations significantly dropped in the groups exposed to the highest doses. In this way, an important point is revealed concerning the food safety from L. edodes, once its chronic and high consumption could contribute to macro and micronutrients deficiency. Additionally, we speculate that the daily use of L. edodes could be unsuccessful for patients in mineral therapy besides being able to be unsafe for individuals with some propensity to mineral deficiency.

RESUMO

Cascas de café são fonte de carboidratos e nutrientes que podem ser bioconvertidos em produtos de interesse como enzimas. Lacases são cobre polifenol oxidases que oxidam compostos fenólicos, enquanto reduzem oxigênio molecular à água e; sua baixa especificidade a substratos permite sua aplicação em várias áreas como indústria têxtil, de alimentos e biorremediação. Os objetivos desse trabalho foram avaliar a capacidade de produção de lacase de três linhagens de fungos basidiomicetos (Lentinula edodes U6/1, Pleurotus ostreatus U6/9 e Pleurotus florida U6/10) por fermentação submersa com cascas de café e avaliar o uso de cobre como indutor dessa enzima. A casca de café mostrou ser um bom substrato para produção de lacases e das três linhagens testadas Pleurotus ostreatus (U6/9) foi a mais produtiva (22,5 U mL-1). A melhor fonte de nitrogênio para produção de lacases de Pleurotus ostreatus (U6/9) foi o extrato de levedura na concentração de 9 g/L (20 U mL-1). A adição de 150 µM de CuSO4 resultou na indução significativa na produção de lacases nessa linhagem (21 U mL-1)no 12° dia de cultivo.

Coffee husks are a source of carbohydrates and nutrients that may be bioconverted into products of interest, such as enzymes. Laccases are copper polyphenol oxidases that oxidize phenolic compounds while reducing molecular oxygen to water. Laccase?s low specificity to substrates allows its application in several areas such as textiles, food processing and bioremediation industries. The aims of this study were to evaluate the potential to produce laccase from three strains of basidiomycetous fungi (Lentinula edodes U6/1, Pleurotus ostreatus U6/9, and Pleurotus florida U6/10) by submerged fermentation with coffee husks, and to evaluate the use of copper as an inducer of the enzyme. Coffee husk proved to be a good substrate for laccase production, with Pleurotus ostreatus (U6/9) being the most productive strain (22.5 U mL-1). The best source of nitrogen for laccase production of Pleurotus ostreatus (U6/9) was yeast extract 9 g/L (20 U mL-1). The addition of CuSO4 (150 µM) resulted in significant induction of laccase (21 U mL-1) on the 12th day of cultivation.

Cáscaras de café son fuente de carbohidratos y nutrientes que pueden ser bioconvertidos en productos de interés, tales como enzimas. Lacases son cobre polifenol oxidasas que oxidan compuestos fenólicos, mientras reducen el oxígeno molecular a el agua y; su baja especificidad a sustratos permite su aplicación en diversas áreas, como la industria textil, de alimentos y de biorremediación. Los objetivos de este estudio fueron evaluar la capacidad de producción de lacase de tres linajes de hongos basidiomicetos (Lentinula edodes U6/1, Pleurotus ostreatus U6/9 y Pleurotus florida U6/10) por fermentación sumergida con cáscaras de café, y evaluar el uso del cobre como inductor de esta enzima. La cáscara de café resultó ser un buen sustrato para la producción de lacases y, de las tres linajes probadas, Pleurotus ostreatus (U6/9) fue la más productiva (22,5 U mL-1). La mejor fuente de nitrógeno para la producción de lacases de Pleurotus ostreatus (U6/9) fue el extracto de levadura a una concentración de 9 g L-1 (20 U mL-1). La adición de 150 µM de CuSO4 resultó en la inducción significativa de la producción de lacases en esa linaje (21 U mL-1), en el 12º día de cultivo.

RESUMO

Xylanolytic enzymes produced by Lentinula edodes UFV70, cultivated in eucalyptus sawdust/rice bran medium, were stable at 50, 60 and 65ºC for 21 hours, losing only 15-25% activity. Fungus incubation at 50ºC for 12 hours and at 65ºC for 24 hours increased the amount of xylose produced.

Assuntos

RESUMO

Xylanolytic enzymes produced by Lentinula edodes UFV70, cultivated in eucalyptus sawdust/rice bran medium, were stable at 50, 60 and 65°C for 21 hours, losing only 15-25% activity. Fungus incubation at 50°C for 12 hours and at 65°C for 24 hours increased the amount of xylose produced.

RESUMO

Cascas de café são fonte de carboidratos e nutrientes que podem ser bioconvertidos em produtos de interesse como enzimas. Lacases são cobre polifenol oxidases que oxidam compostos fenólicos, enquanto reduzem oxigênio molecular à água e; sua baixa especificidade a substratos permite sua aplicação em várias áreas como indústria têxtil, de alimentos e biorremediação. Os objetivos desse trabalho foram avaliar a capacidade de produção de lacase de três linhagens de fungos basidiomicetos (Lentinula edodes U6/1, Pleurotus ostreatus U6/9 e Pleurotus florida U6/10) por fermentação submersa com cascas de café e avaliar o uso de cobre como indutor dessa enzima. A casca de café mostrou ser um bom substrato para produção de lacases e das três linhagens testadas Pleurotus ostreatus (U6/9) foi a mais produtiva (22,5 U mL-1). A melhor fonte de nitrogênio para produção de lacases de Pleurotus ostreatus (U6/9) foi o extrato de levedura na concentração de 9 g/L (20 U mL-1). A adição de 150 μM de CuSO4 resultou na indução significativa na produção de lacases nessa linhagem (21 U mL-1) no 12° dia de cultivo.(AU)

Coffee husks are a source of carbohydrates and nutrients that may be bioconverted into products of interest, such as enzymes. Laccases are copper polyphenol oxidases that oxidize phenolic compounds while reducing molecular oxygen to water. Laccases low specificity to substrates allows its application in several areas such as textiles, food processing and bioremediation industries. The aims of this study were to evaluate the potential to produce laccase from three strains of basidiomycetous fungi (Lentinula edodes U6/1, Pleurotus ostreatus U6/9, and Pleurotus florida U6/10) by submerged fermentation with coffee husks, and to evaluate the use of copper as an inducer of the enzyme. Coffee husk proved to be a good substrate for laccase production, with Pleurotus ostreatus (U6/9) being the most productive strain (22.5 U mL-1). The best source of nitrogen for laccase production of Pleurotus ostreatus (U6/9) was yeast extract 9 g/L (20 U mL-1). The addition of CuSO4 (150 μM) resulted in significant induction of laccase (21 U mL-1) on the 12th day of cultivation.(AU)

Cáscaras de café son fuente de carbohidratos y nutrientes que pueden ser bioconvertidos en productos de interés, tales como enzimas. Lacases son cobre polifenol oxidasas que oxidan compuestos fenólicos, mientras reducen el oxígeno molecular a el agua y; su baja especificidad a sustratos permite su aplicación en diversas áreas, como la industria textil, de alimentos y de biorremediación. Los objetivos de este estudio fueron evaluar la capacidad de producción de lacase de tres linajes de hongos basidiomicetos (Lentinula edodes U6/1, Pleurotus ostreatus U6/9 y Pleurotus florida U6/10) por fermentación sumergida con cáscaras de café, y evaluar el uso del cobre como inductor de esta enzima. La cáscara de café resultó ser un buen sustrato para la producción de lacases y, de las tres linajes probadas, Pleurotus ostreatus (U6/9) fue la más productiva (22,5 U mL-1). La mejor fuente de nitrógeno para la producción de lacases de Pleurotus ostreatus (U6/9) fue el extracto de levadura a una concentración de 9 g L-1 (20 U mL-1). La adición de 150 μM de CuSO4 resultó en la inducción significativa de Cáscaras de café son fuente de carbohidratos y nutrientes que pueden ser bioconvertidos en productos de interés, evadura a una concentración de 9 g L-1 (20 U mL-1). La adición de 150 μM de CuSO4 resultó en la inducción significativa de la producción de lacases en esa linaje (21 U mL-1), en el 12º día de cultivo.(AU)

Assuntos

RESUMO

Xylanolytic enzymes produced by Lentinula edodes UFV70, cultivated in eucalyptus sawdust/rice bran medium, were stable at 50, 60 and 65ºC for 21 hours, losing only 15-25% activity. Fungus incubation at 50ºC for 12 hours and at 65ºC for 24 hours increased the amount of xylose produced.

RESUMO

Cascas de café são fonte de carboidratos e nutrientes que podem ser bioconvertidos em produtos de interesse como enzimas. Lacases são cobre polifenol oxidases que oxidam compostos fenólicos, enquanto reduzem oxigênio molecular à água e; sua baixa especificidade a substratos permite sua aplicação em várias áreas como indústria têxtil, de alimentos e biorremediação. Os objetivos desse trabalho foram avaliar a capacidade de produção de lacase de três linhagens de fungos basidiomicetos (Lentinula edodes U6/1, Pleurotus ostreatus U6/9 e Pleurotus florida U6/10) por fermentação submersa com cascas de café e avaliar o uso de cobre como indutor dessa enzima. A casca de café mostrou ser um bom substrato para produção de lacases e das três linhagens testadas Pleurotus ostreatus (U6/9) foi a mais produtiva (22,5 U mL-1). A melhor fonte de nitrogênio para produção de lacases de Pleurotus ostreatus (U6/9) foi o extrato de levedura na concentração de 9 g/L (20 U mL-1). A adição de 150 μM de CuSO4 resultou na indução significativa na produção de lacases nessa linhagem (21 U mL-1) no 12° dia de cultivo.

Coffee husks are a source of carbohydrates and nutrients that may be bioconverted into products of interest, such as enzymes. Laccases are copper polyphenol oxidases that oxidize phenolic compounds while reducing molecular oxygen to water. Laccase’s low specificity to substrates allows its application in several areas such as textiles, food processing and bioremediation industries. The aims of this study were to evaluate the potential to produce laccase from three strains of basidiomycetous fungi (Lentinula edodes U6/1, Pleurotus ostreatus U6/9, and Pleurotus florida U6/10) by submerged fermentation with coffee husks, and to evaluate the use of copper as an inducer of the enzyme. Coffee husk proved to be a good substrate for laccase production, with Pleurotus ostreatus (U6/9) being the most productive strain (22.5 U mL-1). The best source of nitrogen for laccase production of Pleurotus ostreatus (U6/9) was yeast extract 9 g/L (20 U mL-1). The addition of CuSO4 (150 μM) resulted in significant induction of laccase (21 U mL-1) on the 12th day of cultivation.

Cáscaras de café son fuente de carbohidratos y nutrientes que pueden ser bioconvertidos en productos de interés, tales como enzimas. Lacases son cobre polifenol oxidasas que oxidan compuestos fenólicos, mientras reducen el oxígeno molecular a el agua y; su baja especificidad a sustratos permite su aplicación en diversas áreas, como la industria textil, de alimentos y de biorremediación. Los objetivos de este estudio fueron evaluar la capacidad de producción de lacase de tres linajes de hongos basidiomicetos (Lentinula edodes U6/1, Pleurotus ostreatus U6/9 y Pleurotus florida U6/10) por fermentación sumergida con cáscaras de café, y evaluar el uso del cobre como inductor de esta enzima. La cáscara de café resultó ser un buen sustrato para la producción de lacases y, de las tres linajes probadas, Pleurotus ostreatus (U6/9) fue la más productiva (22,5 U mL-1). La mejor fuente de nitrógeno para la producción de lacases de Pleurotus ostreatus (U6/9) fue el extracto de levadura a una concentración de 9 g L-1 (20 U mL-1). La adición de 150 μM de CuSO4 resultó en la inducción significativa de Cáscaras de café son fuente de carbohidratos y nutrientes que pueden ser bioconvertidos en productos de interés, evadura a una concentración de 9 g L-1 (20 U mL-1). La adición de 150 μM de CuSO4 resultó en la inducción significativa de la producción de lacases en esa linaje (21 U mL-1), en el 12º día de cultivo.

Assuntos

RESUMO

The antimicrobial activity and mineral composition of shiitake mushrooms were evaluated in four isolates of Lentinula edodes. Mushrooms were cultivated on artificial logs, based on eucalyptus sawdust enriched with 20 percent rice, wheat, or soybean bran, or combination of 10 percent of two of these supplements. The substrates were humidified with a 0.1 percent mate tea extract or water. Logs of Eucalyptus grandis were also used to cultivate the shiitake mushrooms. The antimicrobial activity of an aqueous extract, corresponding to 40 mg of mushroom dry matter, was in some cases, depending on the isolate, able to inhibit both Bacillus subtilis and Escherichia coli K-12, independent of substrate composition or the growth stage of the mushrooms. Nitrogen, phosphorus, potassium, magnesium and calcium concentrations varied according to the substrate on which the mushrooms were cultivated, being, generally, higher with cultivation on artificial rather than natural eucalyptus logs. It could be concluded that, in addition to the fungal isolate, substrate composition and, processing methods must be considered during the production of antimicrobial substance(s) as well as in the mushroom nutritional composition.

RESUMO

The aim of this work was to evaluate the effect of thermal and mechanical shocks on the productivity of Lentinula edodes colonized on 140 Eucalyptus saligna logs at different immersion times in water and in the first flush of production. The logs were immersed in water at low temperature (16ºC) or environmental temperature (22ºC), for 6, 10, 14, 18, 22, 26 and 38 hours. The mechanical shock treatment was accomplished by dropping the logs onto the floor three consecutive times, in a vertical position. Water temperature and immersion time affected L. edodes yield, which increased two to four times when the logs were immersed in cool water for the shortest times (6 and 10 hours). The mechanical shock treatment did not increase the sporophore yield.

O objetivo deste trabalho foi avaliar o efeito do choque térmico e mecânico na produtividade de Lentinula edodes em 140 toras de Eucalyptus saligna, completamente colonizadas pelo fungo, em diferentes tempos de imersão em água e no primeiro fluxo de produção. As toras foram imersas em água resfriada (16ºC) ou à temperatura ambiente (22ºC); os períodos de imersão corresponderam a 6, 10, 14, 18, 22, 26 e 38 horas; o choque mecânico foi acompanhado por três quedas consecutivas da tora, em posição vertical, no chão. A temperatura da água e o tempo de imersão afetaram a produção de L. edodes, resultando em aumentos significativos (2 a 4 vezes) nos tratamentos em que as toras foram submetidas à água resfriada e nos tempos de imersão mais curtos (6 e 10 horas). O choque mecânico não resultou em aumento na produção de basidiomas.

RESUMO

The mycelium growth kinetics and vigor of shiitake (Lentinula edodes (Berk.) Pegler) strains LE 96/17, LE 98/51, LE 98/53, and LE 98/56 were studied under different agar medium compositions. The strains were from the mycological collection of the Módulo de Cogumelos, Faculdade de Ciências Agronômicas, Unesp-Botucatu, Brazil. Mycelium fragments from stock cultures were transferred to Petri dishes with Sawdust extract-Dextrose-Agar medium. The area of growth and vigor (density) of the mycelia were daily recorded with a digital camera, during incubation, until the complete colonization of the Petri dish. The images were analyzed by the freeware UTHSCSA ImageTool, v. 2.0, developed by the University of Texas Health Science Center, San Antonio. The kinetics of mycelium growth, as measured by the mycelium area (mm²), has as a deterministic component an exponential function of Gompertz. The vigor, as evaluated by mycelium color in gray scale, was similar for all strains, reached a maximal value between the 4th and 5th day of incubation and decreased further on. The velocity of growth of L. edodes strains was lower in enriched culture media, while vigor was higher. Digital monitoring permits a objective evaluation of the growth kinetics of L. edodes in vitro.

Avaliou-se o crescimento e vigor das linhagens LE 96/17, LE 98/51, LE 98/53 e LE 98/56 de Lentinula edodes (Berk) Pegler em diferentes composições de meio de cultura. As linhagens foram provenientes da Micoteca do Módulo de Cogumelos da Faculdade de Ciências Agronômicas, Unesp, Campus de Botucatu. Os isolados foram obtidos por propagação vegetativa, pela transferência asséptica do micélio para o meio de cultura de extrato de serragem-dextrose-ágar. O crescimento e vigor do micélio foi fotografado diariamente com uma câmera digital, durante a incubação, até a colonização total da placa de Petri. As imagens foram analisadas pelo programa UTHSCSA ImageTool (freeware), versão 2.0, desenvolvido pela University of Texas Health Science Center, San Antonio, Texas. O modelo estatístico que melhor explicou a cinética de crescimento miceliano em área (mm²), das linhagens de cogumelos L. edodes, tem como componente determinístico a exponencial de uma função Gompertz. O vigor, avaliado através da cor do micélio (em escala de tons do cinza), revelou um comportamento similar entre as linhagens, com valor máximo entre o 4º e 5º dia e, em seguida apresentou declínio. Em meios de cultura mais enriquecidos, a velocidade de crescimento das linhagens de L. edodes foi menor e o vigor maior. O monitoramento digital permite uma avaliação objetiva do crescimento e vigor do L. edodes in vitro.