• Journal of Life Science
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• v.32 no.9
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• pp.678-689
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• 2022

HK shiitake mushroom mycelium (HKSMM), containing 14% β-glucan, is a health functional food ingredient approved individually for liver health by the Ministry of Food and Drug Safety. The immune-enhancing efficacy of a 50% aqueous ethanol extract of HKSMM (designated HKSMM50) was studied in Jurkat cells activated with concanavalin A (ConA). Active hexose correlated compound (AHCC) was used as a positive control. ConA-activated Jurkat cells were treated with HKSMM50 (0, 25, 50, 100 ㎍ g/ml) or AHCC (100 ㎍ g/ml), and cultured for 3 and 6 hours. The nuclear factor of activated T cells (NFAT) protein content in the cytosol and the nucleus was measured by Western blotting. Interleukin-2 (IL-2), interferon-gamma (IFN-γ), and cyclooxygenase-2 (COX-2) were determined using enzyme-linked immunosorbent assay (ELISA) kits. HKSMM50 lowered NFAT content in the cytosol, but elevated NFAT content in the nucleus. The IL-2 and IFN-γ productions were elevated. Meanwhile, both COX-2 activity and apoptosis were suppressed. The efficacy of the AHCC treatment showed similar to those of HKSMM50 treatments. These results indicate that the HKSMM50 exhibited immune-enhancing effects in ConA-treated Jurkat cells by activation of NFAT protein, and suggest that HKSMM could be used as a health functional food ingredient to improve immune functions in humans.

• Mycobiology
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• v.42 no.3
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• pp.279-281
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• 2014

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.

• Journal of Mushroom
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• v.7 no.3
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• pp.110-114
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• 2009

Sawdust bag cultivation of Shiitake mushroom (Lentinula edodes) is getting increase. The mycelia browning on the substrate surface is important for the stable production. The development of methods for the rapid mycelia browning is quite required. In this study changes in intracellular enzyme during the mycelial browning were investigated to find the rapid mycelia browning. Mycelia of L. edodes was changed into brown color while it grew in agar and liquid media like sawdust substrates. Mycelia of L. edodes was started to change color at 25 days after inoculation and browning was occurred in whole mycelia colony at 30 days and browning was completed at 40 days. The activities of enzymes was evaluated in these periodically color changing mycelia. Laccase activity was highest at 15 days after inoculation on PDB, but it gradually decreased from 15 days. Tyrosinase activity drastically increased in period between 30 days and 40 days while mycelia browning was progressed. The kinds of phosphotase identified by electrophoresis were esterase, acid phosphotase, and alkaline phosphotase. Activities of phosphotase were increased before the initiation of mycelial browning but they were decreased after browning.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.423-432
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• 1993

The changes of quality of Fresh Shiitake (Lentinus edodes) was studied in this research work by investigating the effect of low $O_2$ content and high $CO_2$ content, well known as CA Treatment in storage, on the respiration rate and PPO Activity that was the main factor in Shiitake quality decay. CA Condition was conducted in 3 research periods that combined the $O_2$content(1%, 5% and 10%) and $CO_2$ content (5%, 10%, 15% and 20%) and air treatment as the control. The lower $O_2$content was the lower respiration rte that was showed in combination the lower respiration rate that was showed in combination of 20% $CO_2$ and 1% $O_2$ (the lowest), and the control air treatment was the highest . Very low $O_2$ content, conversly, did not show a satisfying result to the product.

• Journal of the Korean Society of Safety
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• v.30 no.5
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• pp.86-91
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• 2015

It is important to provide the farmers with practical and effective information of safety and health for individual crop to prevent or reduce occupational injuries in agricultural sector, since work characteristics and risk factors are not the same for all crops. In this study, risk assessment was carried out for cultivating shiitake mushrooms and then safety measures, which were based on the results of the risk assessment, were summarized and presented as the information of safety and health of shittake farmers. Guidelines for safety and health of the farmers of shiitake mushrooms, which were developed based on the risk assesment and safety measures, can be used by the farmers as self-educational tools or by the agricultural facilitators as an educational material for agricultural safety. It is expected that the guidelines can be useful in preventing occupational injuries of shiitake farmers.

• Journal of Mushroom
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• v.3 no.3
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• pp.109-114
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• 2005

Attempts were made to control Diatrype stigma occurred on the bed-log of shiitake by resistant shiitake strains. In selection test of resistant shiitake strains, 67 out of 77 strains tested were proved to be resistant to D. stigma. Among them, 13 strains including KFRI 5 were effective to inhibit the access of D. stigma, and 7 strains including KFRI 180 remarkably invaded the territory of D. stigma. Among 31 shiitake strains made by hybridization of resistant strains for D. stigma, 8 strains including KFRI 537 inhibited the access of D. stigma, and 4 strains including KFRI 545 invaded the territory of D. stigma. The effects of temperatures and inoculation orders to the resistance were confirmed in PDA plates and test tubes filled with sawdust of Quercus acutissima. Four kinds of temperature treatments as follows were tested: (1) continuous incubation at $14^{\circ}C$, (2) continuous incubation at $25^{\circ}C$, (3) changing of incubation temperature from $14^{\circ}C$ to $25^{\circ}C$ as soon as mycelia of both shiitake and D. stigma meet together, (4) changing of incubation temperature from $25^{\circ}C$ to $14^{\circ}C$ as soon as mycelia of both shiitake and D. stigma meet together. Three kinds of inoculation procedure were tested: (1) inoculation of shiitake 3 days ahead of D. stigma inoculation, (2) inoculation of D. stigma 3 days ahead of shiitake inoculation, (3) simultaneous inoculation of both fungi. In PDA plate test, the strain KFRI 137 showed outstanding ability to inhibit mycelial growth of D. stigma and the strain KFRI 180 invaded into the territory of D. stigma in most of treatments. Hybrid strains, KFRI 545, 546, and 547 were more resistant than their parent strains, KFRI 488 and 405. In test tube examinations, all the strains of shiitake showed high resistance at the treatment of change in temperature from $14^{\circ}C$ to $25^{\circ}C$ when mycelia of both shiitake and D. stigma meet together. On the other hand, resistance of all the strains growing at $25^{\circ}C$ decreased when the temperature was changed into $14^{\circ}C$ after mycelia of both fungi. In these cases, the resistance reached to 7~20% of the highest resistance. The strain KFRI 259 invaded the territory of D. stigma, contrary to PDA plate test. Among the strains, KFRI 393 strain was the most resistant under the continuous incubation at $25^{\circ}C$.

• The Plant Pathology Journal
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• v.28 no.2
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• pp.219-219
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• 2012

• Mycobiology
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• v.39 no.2
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• pp.96-102
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• 2011

We investigated diet supplementation with shiitake mushroom fruiting bodies on biochemical and histological changes in hypercholesterolemic rats. Six-wk old female Sprague-Dawley albino rats were divided into three groups of 10 rats each. A diet containing 5% Lentinus edodes fruiting bodies given to hypercholesterolemic rats reduced plasma total cholesterol, triglyceride, low-density lipoprotein (LDL), total lipid, phospholipids, and the LDL/high-density lipoprotein ratio by 34.33, 53.21, 75.00, 34.66, 25.73, and 71.43%, respectively. Feeding mushroom also significantly reduced body weight in hypercholesterolemic rats. However, it had no detrimental effects on plasma albumin, total bilirubin, direct bilirubin, creatinine, blood urea nitrogen, uric acid, glucose, total protein, calcium, sodium, potassium, chloride, inorganic phosphate, magnesium, or enzyme profiles. Feeding mushroom increased total lipid and cholesterol excretion in feces. The plasma lipoprotein fraction, separated by agarose gel electrophoresis, indicated that L. edodes significantly reduced plasma ${\beta}$ and pre-${\beta}$-lipoprotein but increased ${\alpha}$-lipoprotein. A histological study of hepatic cells by conventional hematoxylin-eosin and oil red-O staining showed normal findings for mushroom-fed hypercholesterolemic rats. These results suggest that shiitake mushrooms could be recommended as a natural cholesterol lowering substance in the diet.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.128-137
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• 1999

In this study, shiitake mushrooms were dried by hot air, vacuum and freeze drying methods and theire physical properties were compared. Since the pore size affects the amount of absorption, the characteristics of water sorption were investigated at various humidities and temperatures. Results showed that the freeze dried product had the greatest pore area and the highest absorption capacity. However, all the dried samples showed similar quality. The browning degrees were severely changed with increased relative humidities and temperatures. Among these drying methods, the freeze drying gave the greatest change in browning degree. The GAB monolayer moisture contents of the dried shiitake mushroom were $5.3{\sim}7.7%$. The prediction model was also provided using parameters such as relative humidity, temperature and pore area.

• Journal of Mushroom
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• v.15 no.1
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• pp.31-37
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• 2017

In this study, we investigated the amino acids content of shiitake mushrooms grown in eight different media and under three different temperature conditions. The sawdust media were supplemented with 4 kinds of nutrients - rice bran, barley, bean curd refuse, and red ginseng refuse in an 8:2 ratio with or without 0.5% calcium chloride, and the fruiting temperature was set to low ($13-15^{\circ}C$), medium ($18-20^{\circ}C$), or high temperatures ($24-26^{\circ}C$). Seventeen amino acids were detected, and the content varied depending on the compositions of the media. The highest total amino acid content (209.7 mg/g) was measured in mushrooms from the media with red ginseng refuse, and the glutamic acid content was the highest (51.3 mg/g) in mushrooms from the media with barley. In terms of fruiting temperature, the amino acid content was the highest (38.2%) at medium temperature followed by the content at low (32.5%) and high temperature (29.3%). The amino acid composition of shiitake mushrooms was similar between the medium and low temperature conditions.