Lentinula edodes extract inhibits matrix metalloproteinase expression and increases typeⅠprocollagen expression via the p38 MAPK/c-Fos signaling pathway in ultraviolet A and B-irradiated HaCaT keratinocytes

Objective:To determine the effect of Lentinula edodes extract on ultraviolet (UV) A and UVB-induced changes in matrix metalloproteinase (MMP) and typeⅠprocollagen expression using human immortalized HaCaT keratinocytes. Methods:Lentinula edodes ethanol extract (LEE) was obtained by extraction with 80％ ethanol for 4 h at 80 ℃. Effect of LEE on UV-induced alteration on the expression and production of MMPs and typeⅠprocollagen in keratinocytes was investigated using ELISA, RT-PCR, and Western blotting assay. To determine the underlying mechanism of LEE-mediated effects, mitogen-activated protein kinase (MAPK) and activator protein 1 signaling pathways were analysed by Western blotting assay. Results:LEE significantly inhibited the expression of MMP-1 and MMP-9 and increased the expression of typeⅠprocollagen in UVA and UVB-irradiated HaCaT keratinocytes. The phosphorylation levels of p38 were significantly inhibited by LEE whereas it did not affect c-Jun N-terminal kinase and extracellular signal-regulated kinase phosphorylation. Suppression of p38 phosphorylation was also accompanied by downregulation of UVA and UVB-induced increase in c-Fos. Conclusions:LEE effectively inhibits the expression of MMP-1 and MMP-9 and increases typeⅠprocollagen production through the p38 MAPK/c-Fos signaling pathway in UVA and UVB-irradiated HaCaT keratinocytes. This findings suggest that Lentinula edodes may be developed as a cosmetic material to suppress UV exposure-mediated skin aging.

Combination Treatment with in Situ Tumor Vaccination Therapy and Nutritional Intervention Utilizing Lentinula Edodes Mycelia Extract for Patient with Lingual Cancer: A Case Report / 日本補完代替医療学会誌

In this report, we introduce the patient who show good prognosis after receiving combination therapy with in situ tumor vaccination therapy and nutritional intervention utilizing Lentinula Edodes Mycelia extract. In addition to the disease status, immune condition was also improved by combination therapy.

Evaluation of the Effect of Lentinula Edodes Mycelia Extract on Immune Function in Healthy Subjects Placebo-controlled, Parallel-group Study / 日本補完代替医療学会誌

In this study, we examined the effects of Lentinula edodes mycelia (LEM) on fatigue and immune function in healthy subjects. 22 people were randomly assigned in a 1:1 ratio to the LEM ingestion group and the placebo group. Daily oral ingestion of LEM for 4 weeks (600 mg/day) significantly improved the VAS fatigue score compared with before treatment (p<0.01). Additionally, NK cell activity was increased by ingestion of LEM (p<0.01) and was higher level compared to the placebo group (p<0.05). These results indicate that oral ingestion of LEM may improve the feeling of fatigue and immune function.

Evaluation of Immune Function of Healthy Volunteer Treated with Oral Lentinula Edodes Mycelia Extract / 日本補完代替医療学会誌

Lentinula edodes mycelia extract has been reported to maintain and improve immune function and QOL in cancer patients. In this study, the effects of Lentinula edodes mycelia extract on immune function were investigated in 10 healthy volunteers. Ten subjects were administrated Lentinula edodes mycelia extract orally for 20 weeks on average (846 mg / day ), and the immunological function (IFNγ production amount, IL-10 production amount, lymphocyte subset)was evaluated before and after ingestion at Fukuoka Tenjin Southern Clinic. Immune function following ingestion of Lentinula edodes mycelia extract showed a tendency of IFNγ production to increase, IL - 10 to decrease, and IFNγ / IL - 10 production ratio to be improved remarkably. No significant change was observed in lymphocyte subsets such as regulatory T cells before and after ingestion. Adverse events during the intake period were not observed. It was suggested that oral intake of Lentinula edodes mycelia extract has an action to improve the immune function of healthy adults.

Evaluation of Quality of Life among Patients with Various Types of Cancer Treated with Oral Lentinula Edodes Mycelia Extract / 日本補完代替医療学会誌

Extract of Lentinula edodes mycelia (LEM) reportedly maintains and improves the quality of life (QOL) of patients with cancer who undergo chemotherapy. We investigated the influence of LEM extract on the QOL of 73 Japanese patients with different backgrounds and stages of cancer who were undergoing various types of therapy at 16 institutions. All patients were orally administered with LEM (1200 mg/day) for four weeks. We compared changes in their QOL before and after taking LEM using the EORTC-QLQ-C30. The QOL scores for emotional function and fatigue were significantly improved after LEM intake. Global QOL and physical function scores improved only in patients with cancer at stages III and IV. These findings suggest that oral LEM intake improves the QOL of patients with advanced cancer.

Development and Molecular Characterization of Novel Polymorphic Genomic DNA SSR Markers in Lentinula edodes

Sixteen genomic DNA simple sequence repeat (SSR) markers of Lentinula edodes were developed from 205 SSR motifs present in 46.1-Mb long L. edodes genome sequences. The number of alleles ranged from 3–14 and the major allele frequency was distributed from 0.17–0.96. The values of observed and expected heterozygosity ranged from 0.00–0.76 and 0.07–0.90, respectively. The polymorphic information content value ranged from 0.07–0.89. A dendrogram, based on 16 SSR markers clustered by the paired hierarchical clustering' method, showed that 33 shiitake cultivars could be divided into three major groups and successfully identified. These SSR markers will contribute to the efficient breeding of this species by providing diversity in shiitake varieties. Furthermore, the genomic information covered by the markers can provide a valuable resource for genetic linkage map construction, molecular mapping, and marker-assisted selection in the shiitake mushroom.

Lentinula edodes based GIS mapping, biometabolites and antiinflamatory activity of wild edible mushrooms from tropical 'sacred grove' forests of Meghalaya, India / Mapas basados en GIS deLentinula edodes, biometabolitos y actividad antiinflamatoria de los hongos silvestres comestibles de los bosques tropicales "bosque sagrado" de Meghalaya, India

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.

Identification of Single Nucleotide Polymorphism Markers in the Laccase Gene of Shiitake Mushrooms (Lentinula edodes)

We identified single nucleotide polymorphism (SNP) markers in the laccase gene to establish a line-diagnostic system for shiitake mushrooms. A total of 89 fungal isolates representing four lines, including Korean registered, Korean wild type, Chinese, and Japanese lines, were analyzed. The results suggest that SNP markers in the laccase gene can be useful for line typing in shiitake mushrooms.

Isolation and Characterization of Monokaryotic Strains of Lentinula edodes Showing Higher Fruiting Rate and Better Fruiting Body Production

The effects of monokaryotic strains on fruiting body formation of Lentinula edodes were examined through mating and cultivation of the mated dikaryotic mycelia in sawdust medium. To accomplish this, monokaryotic strains of L. edodes were isolated from basidiospores of the commercial dikaryotic strains, Chamaram (Cham) and Sanjo701 (SJ701). A total of 703 matings (538 self-matings and 165 outcrosses) were performed, which generated 133 self-mates and 84 outcross mates. The mating rate was 25% and 50% for self-mating and outcross, respectively. The bipolarity of the outcross indicated the multi-allelic nature of the mating type genes. The mating was only dependent on the A mating type locus, while the B locus showed no effect, implying that the B locus is multi-allelic. Next, 145 selected dikaryotic mates were cultivated in sawdust medium. The self-mated dikaryotic progenies showed 51.3% and 69.5% fruiting rates for Cham and SJ701, respectively, while the fruiting rate of the outcross mates was 63.2%. The dikaryotic mates generated by mating with one of the monokaryotic strains, including A20, B2, E1, and E3, showed good fruiting performance and tended to yield high fruiting body production, while many of the monokaryotic strains failed to form fruiting bodies. Overall, these findings suggest that certain monokaryotic strains have traits enabling better mating and fruiting.

First Report of Stemonitis splendens Rostaf Causing Bark Decay of Oak Logs Used for Shiitake Cultivation in Korea

Severe bark decay disease was observed on oak logs at a shiitake cultivation farm in Geochang-gun, Gyeongnam province. The symptoms observed were fruiting bodies that had developed on the top and side surface of oak logs. As a result, the bark came off easily exposing the sapwood. Slime mold specimens collected from oak logs showed developing fruiting bodies comprising of stalks, hypothallus, capillitium, and columella, and the causal agent of bark decay disease was identified as Stemonitis splendens on the basis of morphological characteristics. To our knowledge, this is the first report of Stemonitis splendens causing bark decay of oak logs used for shiitake mushroom cultivation in Korea.

Determination of Glucan Contents in the Fruiting Bodies and Mycelia of Lentinula edodes Cultivars

Shiitake mushrooms (Lentinula edodes) containing beta-glucans may be beneficial for human health; they have been used in the treatment of cancer, hypertension, and high cholesterol levels. The objective of this study was to determine the beta-glucan content in different sections of the fruiting bodies and mycelia of ten shiitake mushroom cultivars. The measured beta-glucan content ranged from 20.06 +/- 1.76% to 44.21 +/- 0.13% in the pileus sections, and from 29.74 +/- 1.40% to 56.47 +/- 4.72% in the stipe sections. The results of this study indicate that the variance in beta-glucan content dependent on the shiitake cultivar, and that the beta-glucan content is higher in the stipe than in the pileus.

Influence of Food Waste Compost on the Yield and Mineral Content of Ganoderma lucidum, Lentinula edodes, and Pholiota adipose Fruiting Bodies

The objectives of this study were to evaluate applicability of food waste compost (FWC) as a substrate for cultivation of Ganoderma lucidum, Lentinula edodes, and Pholiota adipose, and to determine contents of Ca, Mg, Na, and K in fruiting bodies (FB). FB yield per substrate in FWC-free controls was 53 +/- 4 g/kg for G. lucidum, 270 +/- 90 g/kg for L. edodes, and 1,430 +/- 355 g/kg for P. adipose. Substrates supplemented with FWC showed the highest FB production at FWC content of 10% for G. lucidum (64 +/- 6 g/kg), and 13% for L. edodes (665 +/- 110 g/kg) and P. adipose (2,345 +/- 395 g/kg), which were 1.2~2.5 times higher than the values for the controls. P. adipose contained higher amounts of mineral elements than the other species. Ca, Mg, Na, and K content in FB did not show a significant relation to FWC content.

Produção de lacase de fungos basidiomicetos por fermentação submersa com cascas de café / Produccin de lacase de hongos basidiomicetos por fermentación sumergida con cáscaras de café / Laccase production from basidiomycetes by submerged fermentation with coffee hukss

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.

Thermostability of xylanolytic enzymes produced by Lentinula edodes UFV70

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.

Effects of Aeration of Sawdust Cultivation Bags on Hyphal Growth of Lentinula edodes

The effects of aeration through lid filters on the hyphal growth of Lentinula edodes (oak mushroom) in sawdust cultivation bags were investigated. The aeration treatment levels were traditional 27 mm hole cotton plugs, cotton balls and combinations of seven hole sizes x two hole positions (up and under) in the lids covering plastic bags containing 1.4 kg sawdust medium at 63% moisture that had been autoclaved for one hour and inoculated with sawdust spawn of L. edodes strain 921. Aeration treatment effects were measured based on the CO2 concentration at the 15th wk, as well as the hyphal growth rate and degree of weight loss of bags every 14 days for 15 wk. In bags with traditional cotton plugs, the CO2 concentration was 3.8 +/- 1.3%, daily mean hyphal growth was 2.3 +/- 0.6 mm and daily mean weight loss was 0.84 +/- 0.26 g. In the bags with 15 mm diameter holes, the CO2 concentration was 6.0 +/- 1.6%, daily hyphal growth was 2.8 +/- 0.2 mm and daily weight loss was 0.86 +/- 0.4 g. The bags with 15 mm holes had a higher CO2 concentration and lower water loss than bags with other hole sizes, but the hyphal growth was not significantly different from that of other bags. The weight loss of bags increased proportionally relative to the lid hole sizes. Taken together, these results indicate that traditional cotton plugs are economically efficient, but 15 mm hole lids are the most efficient at maintaining hyphal growth and controlling water loss while allowing CO2 emissions.

Produção de lacase de fungos basidiomicetos por fermentação submersa com cascas de café / Laccase production from basidiomycetes by submerged fermentation with coffee hurks / Producción de lacase de hongos basidiomicetos por fermentación sumergida con cascaras de café

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.

Antimicrobial activity and mineral composition of shiitake mushrooms cultivated on agricultural waste

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.

Safety Evaluation of Extract from Cultured Lentinula edodes Mycelia; Study of Acute Toxicity, Genotoxicity and Inhibiting Effect of Drug-Metabolizing Enzyme, Cytochrome P-450 3A4 / 日本補完代替医療学会誌

<i>Objective</i>: Extract from cultured <i>Lentinula edodes</i> mycelia (L.E.M.) is a food ingredient possessing various pharmacologic actions such as immunomodulatory properties, antitumor and hepatoprotective effects. In Japan, it has been used as a health food for 30 years or more.<br> In the present study to evaluate the safety of L.E.M., a genotoxicity study and acute toxicity study were conducted. In addition, the inhibitory effect of drug-metabolizing enzyme by L.E.M. was tested<i> in vitro</i>, to gain insight on the interaction with medicines.<br> <i>Methods</i>: The genotoxicity study was performed using a bacterial reverse mutation assay and a <i>in vivo</i> mammalian bone marrow cell chromosomal mutation assay. The acute toxicity study was performed using a single-dose oral toxicity test in rats. Inhibitory activity of cytochrome P-450 3A4 (CYP3A4), one of the most important drug-metabolizing enzymes, by L.E.M. was tested using a baculovirus-expressed system.<br> <i>Results</i>: In the genotoxicity study, mutagenicity was negative for both bacterial reverse mutation assay and <i>in vivo</i> mammalian bone marrow cell chromosomal mutation assay. In the acute toxicity study, no toxic symptoms were observed by single dose oral administration of L.E.M. at a dose of 10,000 mg/kg BW in rats. This implies LD₅₀>10,000 mg/kg BW. No inhibitory activity of CYP3A4 by L.E.M. was observed at in the <i>in vitro</i> screening system to investigate drug-L.E.M. interaction.<br> <i>Conclusion</i>: It is believed L.E.M. is a safety ingredient for foods used in complementary and alternative medicine, since it was toxicologically safe and showed no inhibitory activity of CYP3A4 in the studies conducted.<br>

The Safety of Excessive Intake of the Food Containing Extract of Cultured Lentinula edodes Mycelia (L.E.M.) in Healthy Adult Volunteers / 日本補完代替医療学会誌

<i>Objective</i>: In this study, we evaluated the safety of excessive intake of granular foods containing extract of cultured <i>Lentinula edodes </i>mycelia (L.E.M.) in healthy adult volunteers.<br> <i>Methods</i>: Eleven subjects (8 males and 3 females, ages 33.4 ± 9.4) consumed the test foods containing 5,400 mg L.E.M. a day, three times the recommended daily intake, for 4 weeks.<br> <i>Results</i>: No adverse effect by excessive intake of test foods was observed in physical and clinical exam. No severe symptom was observed, except for mild gastrointestinal symptom such as soft stool in a subject who has hypersensitive intestine.<br> <i>Conclusion</i>: These results suggest that the granular food containing L.E.M. is safe in healthy adults, even if excessive amount up to 5,400 mg a day is consumed.<br>

Screening and Optimal Extraction of a New Antidementia beta-Secretase Inhibitor-Containing Mushroom

To produce a potent antidementia beta-secretase inhibitor from a mushroom, the beta-secretase inhibitory activities of various mushroom extracts were determined. Methanol extracts of Lentinula edodes exhibited the highest inhibitory activity (40.1%). The inhibitor was maximally extracted when a fruiting body of L. edodes was treated with 50% methanol at 40degrees C for 24 h.