• Mycobiology
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• v.36 no.4
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• pp.270-273
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• 2008

Trichoderma spp. cause large crop losses of the cultivated shiitake mushroom, Lentinula edodes. We bred several shiitake strains that are resistant to Trichoderma spp. using di-mon mating to establish a useful method for controlling the greenmold disease. We examined the competitive ability of L. edodes against Trichoderma spp. using a dual culture system to select resistant strains. By screening Trichoderma-resistant strains, we found that among 11 parental strains, 4 strains, including KFRI 36, were confirmed resistant strains. They showed especially strong resistance to T. harzianum, which formed deadlock after mycelial contact and then invaded into the territory of T. harzianum. KFRI 171 also showed resistance to T. atroviride strains. Among 13 strains, which were made by hybridization of shiitake strains, 5 were confirmed to be resistant to Trichoderma, including KFRI 58-1. Their resistance was not correlated to the resistant activity of their parents’ strains. Two strains lose resistance and two strains acquire resistance compared to their parents’ strains. In SEM observation, the mycelium of L. edodes at the interaction zone of Lentinula-Trichoderma was rugged and swollen by T. harzianum.

• The Plant Pathology Journal
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• v.28 no.4
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• pp.341-356
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• 2012

Shiitake (Lentinula edodes) is the most economically important cultivated mushroom, but yields are impacted by its competitor, Trichoderma spp. We previously found two unidentified Trichoderma species growing in bedlogs and sawdust shiitake media in Korea. Here, we identify and re-describe those two species based on molecular sequence data, morphology, and culture characteristics. Well-supported clades based on phylogenetic analyses of internal transcribed spacer, translation elongation factor 1-${\alpha}$, and RNA polymerase subunit II sequences grouped one of the unidentified Trichoderma spp. with Hypocrea pseudogelatinosa and the other with Hypocrea pseudostraminea, and their morphologies matched well with the original descriptions of the two Hypocrea species. This study reports the first phylogenetic analyses of H. pseudogelatinosa and Japanese strains of H. pseudostraminea. Based on the phylogenetic results, we redescribed these two species using modern taxonomic concepts in Hypocrea/Trichoderma.

• Journal of Biosystems Engineering
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• v.19 no.2
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• pp.112-123
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• 1994

At present, no appropriate drying conditions can be found for the heated-air drying of mushroom in Korea. Usually, mushroom is being dried at the temperature range of 40 to $50^{\circ}C$ until the moisture content reaches 10~13% (wb). However, drying characteristics of the mushroom should be investigated for quality improvement and efficient drying operation of the mushroom. The results of this study may be summarized as follows ; 1. The effect of air temperature on the rate of drying was greater than that of relative humidity for drying of mushroom, and the rate of drying was increased with increase in the air temperature. 2. Drying rate for Shiitake mushroom showed falling-rate period of drying without constant-rate period of drying. Drying rate for Oyster mushroom showed a short constant-rate period at the initial stage of drying process, and followed by falling-rate period of drying. 3. Exponential and App.-Diffusion models were found to describe well the drying process of Shiitake mushroom. Exponential and Thompson models for Oyster mushroom in which Thompson model was the most suitable for Oyster mushroom. 4. The equilibrium moisture content of the mushroom decreased with decrease in the air temperature and increase in the relative humidity. In room condition($20^{\circ}C$, 54% RH), the calculated values of the equilibrium moisture content showed 11.17% for Shiitake mushroom and 13.19% for Oyster mushroom, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.2
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• pp.133-138
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• 1991

Several quality indices of Shiitake mushroom (Lentinus edodes) were measured during storage at modified atmosphere (MA) conditions made by plyethylene film bag with different thicknes. IN the mushrooms kept in the thicker film bag, larger amounts of ethyl alcohol and acetaldehyde were produced during storage. The lowest weight loss was marked by the mushrooms kept in 0.06mm thick film bag. Protein content of the mushrooms was increased with the storage period without any storage period without any significant trend depended on the storage treatments and electrophoresis pattern of protein was changed little in the mushrooms kept in 0.04mm thick P.E. film bag during storage.

• The Korean Journal of Food And Nutrition
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• v.35 no.6
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• pp.531-536
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• 2022

Umami taste-yielding foods, such as, Joseonganjang, dried anchovies, dried shiitake, dried Konbu (kelp), and Yukjeot, are widely used in the Korean cuisine as soup base. While Umami taste enhancement related to Kokumi taste substances has been proposed in human sensory studies, the potential action of Kokumi taste substances has not been explored on calcium-sensing receptors (CaSR), here referred to as Kokumi taste receptors. In this study, we investigated the effect of Umami taste-yielding foods on Kokumi taste receptors using cells expressing human CaSR. We monitored the temporal changes in intracellular Ca²⁺ in HEK293T cells expressing CaSR in response to aqueous extract of Joseonganjang, dried anchovies, dried shiitake, dried Konbu, and Yukjeot. Kokumi substances tested-glutathione and γ-Glu-Val-Gly- evoked intracellular Ca²⁺ influx in a concentration-dependent manner. A similar increment of intracellular Ca²⁺ influx was induced by Joseonganjang, Yukjeot, and dried anchovies, but not by dried shiitake and dried Konbu. Only Joseonganjang- and Yukjeot-evoked intracellular Ca²⁺ influx was significantly reduced by NPS 2143, a CaSR-specific antagonist. These data indicated that some Umami substances/Umami-yielding materials could activate CaSR, but this property was not observed for all the Umami tasting substances.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.535-542
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• 2023

We investigated the anti-inflammatory effects of shiitake mushroom and kelp (SMK) mixture extracts in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 cells. Treatment of RAW 264.7 cells with LPS significantly increased NO (nitric oxide) production, pro-inflammatory cytokines (tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-6, and IL-1β), and inflammation-related genes (COX-2 and inducible nitric oxide synthase (iNOS)). In cytotoxicity testing using RAW 264.7 cells, SMK mixture extracts in the range of 1-16 ㎍/mL did not inhibit cell proliferation. However, SMK mixture extracts significantly inhibited NO production in a dose-dependent manner (p<0.05). SMK treatment significantly decreased TNF-α, IL-6, IFN-γ, and IL-1β levels compared to the LPS group, and similarly, pro-inflammatory cytokine mRNA levels also decreased. SMK mixture extracts reduced the mRNA expression of COX-2 and iNOS in RAW 264.7 cells compared to LPS (p<0.05). The above results show that SMK mixture extracts suppressed the inflammatory response induced by LPS. In particular, the extracts were shown to regulate the inflammatory response by suppressing the expression of inflammatory cytokines and inflammation-related enzymes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.250-254
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• 2007

In an attempt to find ways of improving the quality of dried Shiitake mushroom, this study compared a conveyer-type far-infrared drying method with a traditional heated air drying method. The conveyer-type far-infrared dryer was performed at air velocity of 0.6 and 0.8 m/s under drying air temperature of 60, 70 and $80^{\circ}C$, respectively. Drying characteristics, antioxidant activities and the antioxidant compounds of Shiitake mushroom dried by far-infrared dryer were investigated. Generally, drying rate with the conveyer-type far-infrared drying method was faster than that with the traditional heated air drying method. In the conveyer type far infrared drying method, drying rates were increased with increasing temperature and air velocity. The loss of antioxidant activities during the conveyer-type far-infrared drying method at 60-0.6, 60-0.8, and $70^{\circ}C-0.6m/s$ was less than the traditional drying method. However, the loss of antioxidant activities at 70-0.8, 80-0.6, and $80^{\circ}C-0.8m/s$ was higher than that of the traditional drying method. Therefore, the conveyer type far infrared drying conditions with below $70^{\circ}C$ and 0.6 m/s air velocity may produce dried Shiitake mushroom with relatively higher antioxidant activities and antioxidant compounds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.874-881
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• 2015

In the food industry, thermal treatment is an important process for extending shelf-life of foods. However, heating process affects the physicochemical, nutritional, and microbial properties of foodstuff such as color, texture, pH, and proximate compositions. This study was conducted to select an optimal thermal treatment by observing physicochemical, nutritional, and microbial effects of shiitake mushrooms with different thermal treatment methods. Shiitake mushrooms were washed and sliced equally ($5cm{\times}0.5cm{\times}0.5cm$) and then heat-treated by three methods. Samples were heated in $100^{\circ}C$ boiling water, steamed for 10 min, or pan fried at $130^{\circ}C$ for 4 min. Total color difference values showed significantly increasing tendency with treatment time. For pH values, boiling water-treated mushrooms showed increasing tendency according to increased thermal treatment. For the results of hardness, boiling water or pan frying-treated mushrooms showed reduced tendency within 1 min. In the case of steam-treated mushrooms, hardness values were maintained for 1 min. Organic acid contents of steam-treated sample showed the lowest value among treatments. For microbial counts, steam-treated samples for 3 min showed the lowest value. Consequently, the results of this study suggest that steam treatment could be the optimal thermal treatment to minimize quality loss of shiitake mushrooms.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.402-408
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• 2016

Master packaging system consists of an inner individual package and secondary outer package. During the stages of chilled transport and distribution, the combination of primary individual package and secondary package was used to maintain a modified atmosphere for shiitake mushrooms. During the retail stage at higher temperature ($25^{\circ}C$), the primary individual package was exposed to display conditions after dismantling of the secondary packaging. The master packaging system was constructed to contain eight individual $30-{\mu}m$ thick polypropylene film bags of 500 g shiitake mushrooms inside a $40-{\mu}m$ low-density polyethylene bag. Carbon dioxide absorbent material [$Ca(OH)_2$] and/or moisture absorbent (superabsorbent polymer) were designed in their required amounts based on respiration characteristics and then applied to the outer secondary packaging in sachet form. Gas concentration of the packaging, temperature, and humidity were monitored throughout transport and storage. The quality of shiitake mushrooms was measured at the retail stage to determine the packaging effect. During the distribution stage of 108 h, $O_2$ and $CO_2$ concentrations in the master packaging system were maintained at 9~11% and 1~4% in the inner packaging, respectively, which are good for quality preservation. Compared to the control, the master packaging with $CO_2$ and/or moisture absorbents improved mushroom preservation and particularly reduced decay.

• Journal of Mushroom
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• v.19 no.3
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• pp.184-190
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• 2021

With the development of sawdust medium cultivation technology, Lentinula edodes (shiitake mushroom) has become the most extensively produced and consumed mushroom globally. In this study, the approximate composition, nutritional components, and bioactive compounds of L. edodes were analyzed and compared for the five sawdust-cultivated shiitake mushrooms cultivars namely Sanjo701ho, Sanjo707ho, Sanjo715ho, Chamaram, and L808. The approximate range of the composition of freeze-dried shiitake mushrooms was 4.06-5.92 g/100 g of ash, 0.75-1.02 g/100 g of crude fat, and 21.24-29.15 g/100 g of crude protein. Sanjo701ho had the highest trehalose content (9.60±0.08 g/100 g), total polyphenol content (3.49±0.04 mg GAE/g), and total flavonoid content (1.33±0.03 mg QE/g) among the other shiitake mushroom cultivars. The total amino acid content was as follows: glutamic acid>aspartic acid>leucine. Glycine, alanine, valine, isoleucine, leucine, and phenylalanine contents were significantly decreased in the following sequence: Sanjo707ho, Sanjo715ho, Sanjo701ho, Chamaram, and L808. Crude protein, trehalose, and six types of amino acids were identified as classification indicators for the five cultivars of sawdust-cultivated shiitake mushrooms.