• 한국균학회소식:학술대회논문집
• /
• 2015.11a
• /
• pp.37-37
• /
• 2015

dsRNA was found in malformed cultures of Lentinula edodes strain FMRI0339, one of the three most popular sawdust cultivated commercial strains of shiitake, and was also found in healthy-looking fruiting bodies and actively growing mycelia. Cloning of the partial genome of the dsRNA revealed the presence of the RdRp sequence of a novel L. edodes mycovirus (LeV), and sequence comparison of the cloned amplicon showed an identical sequence to known RdRp genes of LeV found in strain HKA. The meiotic stability of dsRNA was examined by measuring the ratio of the presence of dsRNA among sexual monokaryotic progeny. More than 40% of the monokaryotic progeny still contained the dsRNA, indicating the persistence of dsRNA during sexual reproduction. Comparing the mycelia growth of monokaryotic progeny suggested that, although variations in the growth rate existed among progeny and virus infection was observed in highly actively growing progeny, there appeared to be a tendency toward a lower frequency of virus incidence in actively growing progeny. This study attempted to cure the edible mushroom L. edodes strain FMRI0339 of the L. edodes mycovirus (LeV) in order to obtain an isogenic virus-free fungal strain as well as a virus-infected strain for comparison. Mycelial fragmentation, followed by being spread on a plate with serial dilutions resulted in a virus-free colony. Viral absence was confirmed with gel electrophoresis after dsRNA-specific virus purification, Northern blot analysis, and PCR using reverse transcriptase (RT-PCR). Once cured, all of fungal cultures remained virus-free over the next two years. Interestingly, the viral titer of LeV varied depending on the culture condition. The titer from the plate culture showed at least a 20-fold higher concentration than that grown in the liquid culture. However, the reduced virus titer in the liquid culture was recovered by transferring the mycelia to a plate containing the same medium. In addition, oxygen-depleted culture conditions resulted in a significant decrease of viral concentration, but not to the extent seen in the submerged liquid culture. Although no $discernable phenotypic changes in colony morphology were observed, virus-cured strains showed significantly higher growth rates and mycelial mass than virus-infected strains. We were also explored effects of LeV on fruiting body formation and mushroom yield. The fruiting body formation yield of virus-free L. edodes was larger than virus-infected L. edodes. These results indicate that LeV infection has a deleterious effect on mycelial growth and fruiting body formation. In addition, we have been investigated host-parasite interaction between L. edodes and its mycovirus interaction to study viral mechanism by establishment of proteomics.

• KSBB Journal
• /
• v.22 no.1
• /
• pp.1-6
• /
• 2007

The optimum liquid culture conditions were investigated for cell growth and polysaccharide production from liquid culture of Lentinus edodes. In flask culture, the optimal medium compositions for the polysaccharide production contained glucose 60 g/L, yeast extract 10 g/L, $KH_2PO_4$ 2.0 g/L, and $MgSO_4{\cdot}7H_2O$ 1.0 g/L. The maximum mycelial growth and polysaccharide production were 11.01 g/L and 1.64 g/L, respectively. In bioreactor, through the variation of aeration in order to increase mycelial growth and polysaccharide production, the maximum mycelial growth and polysaccharide production were 55.9 g/L at 8th day and 7.34 g/L at 7th day of cultivation with 1.5 vvm, respectively.

• The Korean Journal of Mycology
• /
• v.10 no.1
• /
• pp.33-39
• /
• 1982

Carpophores of ten Korean strains of Lentinus edodes (Berk.) Singer, an antitumor polysaccharide producing fungus, were extracted with 0.1N NaOH solution. The extracts were dialized for seven days in distilled water and lyophilized to produce crude polysaccharide powders. Thus obtained crude polysaccharide samples were assayed for sugar contents by colorimetric method with anthrone reagent. Among ten strains examined Lentinus edododes-DMC7 was found to be the richest strain in polysaccharide content of carpophores. By shake culture experiment for biomass production, L. edodes-DMC7 was found to be the second most productive strain among seven strains examined. Cultural characteristics of L. edodes-DMC7 were investigated by shake culture method. The best result was obtained when L. edodes-DMC7 was cultured in the medium containing glucose 8g, starch 80g, yeast extract 12g, $KH_2PO_4\;0.87g,\;MgSO_4{\cdot}7H_2O\;O.5g,\;CaCl_2\;0.3g,\;FeSO_4{\cdot}7H_2O\;10mg\;ZnSO_4{\cdot}7H_2O\;4mg,\;CuSO_4{\cdot}5H_2O\;lmg,\;MnCl_2{\cdot}4H_2O\;7mg\;per\;11\;at\;28^{\circ}C$, 180 rpm, for 12 days. Thus thirty-three grams of dry mycelia was obtained per one liter of medium.

• Journal of Korean Society of Forest Science
• /
• v.101 no.1
• /
• pp.77-82
• /
• 2012

Sterilization of oak sawdust at $65^{\circ}C$ for Lentinula edodes bed cultivation can be efficient in sterilization facility cost, but its effect on the mushroom production is uncertain due to high contamination probability. The effective conditions for L. edodes hyphal growth in the low temperature sterilized oak sawdust were investigated with combinations of three sterilization temperatures ($65^{\circ}C$, $100^{\circ}C$ and $121^{\circ}C$) and four cultivation temperatures ($15^{\circ}C$, $20^{\circ}C$, $25^{\circ}C$, and $30^{\circ}C$). L. edodes inoculation density effect was also tested with 1 cm, 2 cm, and 4 cm distance in the sawdust (4%, 11% and 25% inoculation rate by surface area). L. edodes hyphal growth in the sawdust sterilized at $65^{\circ}C$ was as much as at those $100^{\circ}C$ and $121^{\circ}C$ when the fungus cultured below $25^{\circ}C$, but it was greatly reduced when cultured at $30^{\circ}C$. And the sawdust medium with 1cm distance inoculation density was fully occupied with L. edodes hyphae, but those with 2~4cm distance inoculation were contaminated by 4~33%. Therefore, we conclude that low temperature sterilized oak sawdust needs to be cultured under $25^{\circ}C$ after sufficient inoculation by 25% for successful bed cultivation of L. edodes.

• YAKHAK HOEJI
• /
• v.39 no.3
• /
• pp.260-267
• /
• 1995

A lectin from the edible mushroom, Lentinus edodes, was purified through physiological saline extraction, ammonium sulfate fractionation and column chromatographies. On polyacrylamide gel electrophoresis, 0.05M fraction from hydroxyapatite column exhibited adjacent four sharp bands. The partially purified lectin agglutinated the erythrocytes of rabbit, mouse and rat, but not agglutinated human erythrocytes. The lectin's mitogenic effects were tested by its application to human and murine splenic lymphocytes. The results showed that the 0.05M fraction from hydroxyapatite was mitogenic, and the optimal dose of Lentinus edodes lectin was slightly lower than Con A by the culture with murine splenic and human peripheral lymphocytes. Meanwhile, its ability to agglutinate transformed cells was tested by its administration to continuous cell lines L1210 and HeLa cells. The leetin was found to be an agglutinin of tumor cell lines tested by L1210 and HeLa cells.

• Journal of the East Asian Society of Dietary Life
• /
• v.12 no.1
• /
• pp.55-64
• /
• 2002

This study was carried out to investigate quality characteristics of Seolgiddeok containing 0, 1, 3, 5 and 7% of Lentinus edodes powder during storage. The water content of Seolgiddeok changed little with the length of storage and the amount of Lentinus edodes powder added. Hunter′s color L value of Seolgiddeok decreased and "a"and "b"value were increased significantly by increasing the amount of Lentinus edodes powder. The hardness, gumminess, adhesiveness, chewiness and cohesiveness of Seolgiddeok decreased, but springiness increased by increasing the amount of Lentinus edodes powder. Seolgiddeok added with 3% Lentinus erodes earned the highest scores in color, taste, softness, chewiness, moistness and overall preference. From the above results of sensory and texture analyses, an addition of 3% Lentinus edodes to Seolgiddeok showed the best result in quality.

• Journal of the East Asian Society of Dietary Life
• /
• v.16 no.3
• /
• pp.364-370
• /
• 2006

To evaluate the potential possibility of Lentinus edodes as an a sauce ingredient of sauce, the physicochemical and sensory characteristics of Lentinus edodes and Agaricus bisporus brown sauce were compared. The same mother sauce was used to prepare the for preparation of two different types of sauce was the same. The contents of moisture, crude protein, and crude ash were not different. However, crude fat content was higher in Agaricus bisporus brown sauce and carbohydrate content was higher in Lentinus edodes brown sauce. The amounts of total free amino acids were 1,236.45 mg% in Agaricus bisporus brown sauce and 791.73 mg%, respectively in Lentinus edodes brown sauce. Major free amino acids in both sauces were glutamic acid, alanine, aspartic acid, and arginine. Amino acid derivatives content was higher in Lentinus edodes brown sauce (644.55 mg%) than in Agaricus bisporus brown sauce (595.87 mg%). Major amino acid derivatives were ammonia, taurine, and carnosine in Agaricus bisporus brown sauce and sarcosine, ammonia, -amino isobutyric acid, and phospho ethanolamine in Lentinus edodes brown sauce. The L, a and b values of Lentinus edodes brownumsauce showed a higher tendency those of Agaricus bisporus. The viscosity of Agaricus bisporus brown sauce and Lentinus edodes brown sauces were 1976.67 cP and 2686.67 cP, respectively. The sensory score of color was not different between the both sauces, but those of flavor, taste, and viscosity of Lentinus edodes brown sauce were higher than those of Agaricus bisporus brown sauce. Especially, the sensory evaluation score on the flavor of Lentinus edodes brown sauce (7.6) was recorded higher than that (5.1) of Agaricus bisporus brown sauce. From the As a results, the overall acceptability of Lentinus edodes brown sauce was judged to be superior to than that of Agaricus bisporus brown sauce.

• Journal of Korean Society of Forest Science
• /
• v.98 no.1
• /
• pp.115-124
• /
• 2009

New strain needs to maintain desirable characteristics for long term when it was bred, but in lapse of time it degenerates into a bad condition. Therefore the influence of temperature on the viability and survival rates of Lentinula edodes strains were examined after cryopreservation. Also, liquid nitrogen preservation for L. edodes has been proved to be one of the most reliable method. However, a mechanical damage of strain is inevitable during cryopreservation of the fungus because the fungus is very sensitive to stress of cooling rate in the freezing process. So we tried to find out state change of L. edodes with a programmable freezer. L. edodes strains were preserved at $-20^{\circ}C$, $-80^{\circ}C$ and $-196^{\circ}C$ for 50 days. At $-20^{\circ}C$, its mycelial growth became extinct. When thawed, the growth of mycelia which were preserved at $-80^{\circ}C$ was fastest. Attempts were made to investigate viability of L. edodes strains after freezing at $-80^{\circ}C$ and $-196^{\circ}C$, respectively. As the result, more than 90% showed high survival rate of strains tested at $-80^{\circ}C$ and $-196^{\circ}C$. Mycelial growth between apical and basal parts of colony after freezing preservation for 50 days was compared. At apical and basal parts, the survival rates showed 100% at $-80^{\circ}C$, but 98% and 94% at $-196^{\circ}C$, respectively. We confirmed that the ice crystal formation temperatures of L. edodes strains were $-6.0^{\circ}C$ for Sanlim 1, $-5.5^{\circ}C$ for the Sanlim 2, $-4.0^{\circ}C$ for the Sanlim 3 and $-15.5^{\circ}C$ for the Sanzo 302. These results indicated that L. edodes strains showed completely different responses to the ice crystal formation. We knew the fact that even the same species, especially L. edodes, they displayed completely different responses to the same freezing condition. Also, this has nothing to do with the connection between temperature type and freezing point. And a protocol was tried to minimize state change of L. edodes strains using programmable freezer when they are frozen, but it was not effective on them.

• Journal of Microbiology and Biotechnology
• /
• v.14 no.4
• /
• pp.658-664
• /
• 2004

To find a new utilization of rice bran, nine higher fungi were examined for the production of exo-biopolymer with macrophage stimulating activity from rice bran. Among the exo-biopolymers produced from submerged cultures, Lentinus edodes showed the highest activity, followed by Grifola frondosa, Schizophyllum commune, and Coriolus versicolor. L. edodes also had the most potent macrophage stimulating activity in a liquid culture rather than in a solid culture. In order to improve rice bran utilization and the yield of exo-biopolymer with macrophage stimulating activity, the treatment of Rapidase effectively increased the macrophage stimulating activity (about 30% increase), whereas the other enzymes (Econase, Viscozyme, Ultraflo, Celluclast, and Thermylase) treatments did not increase the macrophage stimulating activity. Exo-biopolymer with macrophage stimulating activity from L. edodes contained mainly neutral sugars (58.7%) with considerable amounts of uronic acid (32.2%) and a small amount of proteins (9.1%). Component sugars of exo-biopolymer consisted of mainly arabinose, galactose, glucose, mannose, and xylose (0.95:0.81:0.96:1.00:0.39, respectively). When the exo-biopolymer was treated with $NaIO_4, NaClO_2$, and pronase, the $NaClO_2$ treatment and pronase digestion had little effect, whereas $NaIO_4$ oxidation significantly decreased the macrophage stimulating activity (47.6% reduction at $100\mug/ml$). Therefore, the carbohydrate moiety in exo-biopolymer from L. edodes plays an important role in the expression of the macrophage stimulating activity.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.36 no.2
• /
• pp.241-245
• /
• 2007

Gangjeong was prepared by adding Lentinus edodes to improve quality of the gangjeong and to give some functional properties. Contents of the crude protein and ash increased with increasing amount of L. edodes, while carbohydrate contents decreased. As the ratio of mushroom in gangjeong increased, lightness and yellowness in Hunter's color value tended to decrease. In terms of texture, 20% and 30% contents of L. edodes made no significant differences in gumminess, brittleness, cohesiveness, and springiness compared to control, whereas hardness showed no difference to control. Gangjeong with 30% L. edodes obtained the highest scores in quality and sensory characteristics.