• Journal of Mushroom
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• v.15 no.4
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• pp.164-167
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• 2017

Biological efficiency (BE), the ratio of fresh mushrooms harvested per dry substrate weight, expressed as the percentage of Lentinula edodes, also known as shiitake, was determined using the 'Sanjo 701' strain stored in the Department of Mushroom at the Korea National College of Agriculture and Fisheries. The mycelia were grown in glass columns with varying levels of moisture content and varying mixing periods of 0.5, 1, 2, and 3 hours. The substrate was sterilized using a steam pressure autoclave sterilizer at normal and high pressure to avoid contamination. The results showed that mycelial growth (126 mm/15 days) was optimized at 55% moisture content. The best mycelial growth of 117 mm/15 days was obtained with 2 hours of mixing time. Normal pressure sterilization yielded better results with mycelial growth of 96 mm/15 days at $100^{\circ}C$ compared to 88 mm /15 days with sterilization at $121^{\circ}C$. Mycelial density was higher, i.e. 3(+++), with normal pressure sterilization compared to 2(++) with high pressure sterilization. Furthermore, sawdust mixed with 5% woodchips increased the substrate porosity and yielded higher mycelial growth. Thus, we demonstrated that the optimum harvest or potential increased yield of shiitake can be obtained by modulating moisture content, mixing time, and substrate porosity.

• The Plant Pathology Journal
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• v.30 no.1
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• pp.82-89
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• 2014

In 2009-2010, unusual symptoms were observed on Pleurotus eryngii grown in mushroom farms in Gyeongnam Province, Republic of Korea. One of the main symptoms was a cobweb-like growth of fungal mycelia over the surface of the mushroom. The colonies on the surface rapidly overwhelmed the mushrooms and developed several spores within 3-4 days. The colonized surface turned pale brown or yellow. The fruit body eventually turned dark brown and became rancid. Koch's postulates were completed by spraying and spotting using isolated strains. The phylogenetic tree obtained from the internal transcribed spacer sequence analysis showed that the isolated fungal pathogen corresponded to Cladobotryum mycophilum (99.5%). In the fungicide sensitivity tests, the $ED_{50}$ values for the isolate with respect to benomyl and carbendazim were from 0.29 to 0.31 ppm. Benzimidazole fungicides were most effective against C. mycophilum, a causal agent of cobweb disease in P. eryngii.

• Mycobiology
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• v.39 no.2
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• pp.85-91
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• 2011

We investigated the effect of nutritional and environmental factors on Ophiocordyceps longissima mycelial growth. The longest colony diameter was observed on Schizophyllum (mushroom) genetics complete medium plus yeast extract, Schizophyllum (mushroom) genetics minimal medium, and Sabouraud dextrose agar (SDA); however, malt-extract yeast-extract agar, SDA plus yeast extract, yeast-extract malt-extract peptone dextrose agar, SDA, oatmeal agar, and potato dextrose agar showed higher mycelia density. A temperature of $25^{\circ}C$ was optimum and 7.0 was the optimum pH for mycelial growth. Colony diameter was similar under light and dark conditions. Maltose and yeast extract showed the highest mycelial growth among carbon and nitrogen sources respectively. The effect of mineral salts was less obvious; however, $K_3PO_4$ showed slightly better growth than that of the other mineral salts tested. Among all nutrition sources tested, complex organic nitrogen sources such as yeast extract, peptone, and tryptone were best for mycelial growth of O. longissima. Ophiocordyceps longissima composite medium, formulated by adding maltose (2% w/v), yeast extract (1% w/v), and $K_3PO_4$ (0.05% w/v) resulted in slightly longer colony diameter. In vitro mycelial O. longissima growth was sustainable and the production of fruiting bodies could be used for commercial purposes in the future.

• Mycobiology
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• v.36 no.1
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• pp.34-39
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• 2008

Schizophyllum commune is an edible and medicinal mushroom widely distributed in the world. The optimal growth conditions for the mycelia of 10 strains of the fungus were investigated. The temperature suitable for the mycelial growth and density was obtained at $30{\sim}35^{\circ}C$. Among the tested conditions, the minimum mycelial growth was found at $15^{\circ}C$. In case of pH, the most favorable growth was found at pH 5. The results indicated that this mushroom well adapted to high temperature and low pH for its mycelial growth. Considering growth phenotype of mycelia, Hamada, Hennerberg, PDA and YM were the most suitable and Lilly, Glucose triptone, Glucose peptone and Hoppkins were the most unfavorable among tested media for the mycelial growth of S. commune. Out of tested carbon sources, dextrin and fructose were the most suitable and lactose, mannose and sorbitol were the unsuitable for the fungus. Compact mycelial density was obtained from most of the carbon sources. Among used nitrogen sources, calcium nitrate, potassium nitrate and alanine were the most appropriate and the most incompatible were ammonium phosphate, histidine, urea and arginine for mycelial growth of S. commune on the culture media. Calcium nitrate, histidine and potassium nitrate showed moderately thin or thin, and rest of nitrogen sources showed compact or moderately compact mycelial density.

• Journal of Mushroom
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• v.18 no.4
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• pp.365-371
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• 2020

In this study, we analyzed the effect of media on the production of carotenoids and mycelia by using Perenniporia fraxinea. Malt extract-based medium with less than 0.1% peptone stimulated the production of carotenoids, and the one with more than 0.2% peptone inhibited its production. P. fraxinea grown in medium without malt extract did not produce carotenoids, although a small amount of peptone was added to the medium.After carotenoid production, the culture broth was separated using simple centrifugation and the supernatant was harvested as a carotenoid solution. Ethanol was used to extract carotenoids from mycelia. Carotenoid solution separated or extracted from the culture solution showed DPPH radical scavenging activity. The antioxidant carotenoids produced by P. fraxinea are derived from natural products, have no toxicity and side effects, and exhibit excellent antioxidant effects; therefore, they can be effectively used to remove oxides produced by active oxygen.

• The Korean Journal of Mycology
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• v.21 no.4
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• pp.310-315
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• 1993

Phanerochaete chrysosporium is a white rot fungus which secrets a family of lignin-degrading enzymes under nutrient limitation. Ligninase was extracellularly produced in agitated submerged cultures of P. chrysosporium, SC 26. Addition of veratryl alcohol(4 mM), and benzyl alcohol(10 mM) with 0.1% Tween 20 to the culture medium stimulated ligninase production. However, ligninase was not detected when both treatments of veratryl alcohol and benzyl alcohol without Tween 20 were added to the medium. Addition of 0.1 % Tween 20 to the culture medium had little effect on ligninase activity. The ligninase activity was maximum on day 5-8 for veratryl alcohol, and benzyl alcohol with 0.1 % Tween 20 additive medium.

• Mycobiology
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• v.48 no.4
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• pp.313-320
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• 2020

In Pleurotus sp., green mold, which is considered a major epidemic, is caused by several Trichoderma species. To develop a rapid molecular marker specific for Trichoderma spp. that potentially cause green mold, eleven Trichoderma species were collected from mushroom farms and the Korean Agricultural Culture Collection (KACC). A dominant fungal isolate from a green mold-infected substrate was identified as Trichoderma pleuroticola based on the sequences of its internal transcribed spacer (ITS) and translation elongation factor 1-α (tef1) genes. In artificial inoculation tests, all Trichoderma spp., including T. atroviride, T. cf. virens, T. citrinoviride, T. harzianum, T. koningii, T. longibrachiatum, T. pleurotum, and T. pleuroticola, showed pathogenicity to some extent, and the observed symptoms were soaked mycelia with a red-brown pigment and retarded mycelium regeneration. A molecular marker was developed for the rapid detection of wide range of Trichoderma spp. based on the DNA sequence alignment of the ITS1 and ITS2 regions of Trichoderma spp. The developed primer set detected only Trichoderma spp., and no cross reactivity with edible mushrooms was observed. The detection limits for the PCR assay of T. harzianum (KACC40558), T. pleurotum (KACC44537), and T. pleuroticola (CAF-TP3) were found to be 500, 50, and 5 fg, respectively, and the detection limit for the pathogen-to-host ratio was approximately 1:10,000 (wt/wt).

• Journal of Mushroom
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• v.22 no.1
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• pp.17-21
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• 2024

Mushroom-based vegan meat has thus far been used as a food for humans instead of pets. However, based on its texture and nutritional content, it is considered suitable for processing into pet treats. In the present study, we developed a prototype dog chew with a sweetening coating added to a fungal mycelium mat obtained by culturing the Basidiomycetous fungus Trametes orientalis. The palatable coating applied to the mycelium mat by plasticizing the mat with glycerol improved the taste and aroma of the existing mat, and the dog consumed it without difficulty. Future improvements may include a softening process to reduce the chewiness level and a procedure to reduce the crude fiber content. Mycelium-mat-based dog chews, manufactured using eco-friendly materials and processes that are not harmful to the environment are expected to enter the market as eco-friendly alternatives to conventional pet treats. Controlling their physical properties require further study.

• Journal of Mushroom
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• v.11 no.2
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• pp.63-68
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• 2013

The fruiting body of honey mushroom, Armillaria gallica, was collected from Gastrodia elata cultivated fields. Pure cultures were isolated from fruiting body tissue of the mushrooms, and cultured on MCM (mushroom complete medium) or PDA (potato dextrose agar) medium. Then, 12 different types of mycelial growth characteristics such as growth rate, colony morphology and rhizomorph formation were obtained. The vitality of the mycelial growth and rhizomorph formation of the fruiting body culture isolates were better on MCM than PDA, suggesting that the optimal culture medium for A. gallica mycelia was MCM. To observe the feature of colony morphology, the subculture of isolates were incubated on MCM. Consequently, we could find the segregated or differentiated colony morphology from isolate type 11 that was similar morphology to isolate type 12. For phylogenetic analysis of the 12 isolates, RAPD (Random Amplified Polymorphic DNA) were performed. The isolate type 12 was not only shown different band patterns of RAPD variation in other 11 isolates, but also commercial strain known as Chunmagyun No. 1. Among the tissue culture isolates of fruiting, strains with better mycelial growth characteristics than Chunmagyun No. 1 were selected. We expect that the new strain can be substituted to commercial strain Chunmagyun No. 1.

• Journal of Mushroom
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• v.21 no.3
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• pp.185-189
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• 2023

This study was conducted to develop a renewable and sustainable bio-material to replace polystyrene (EPS) in fungal-mycelium-based composite using agricultural by-products. Four mushrooms (Ganoderma lucidum, Fomitella fraxinea, Phellinus linteus, and Schizophyllum commune) were cultured in an oak sawdust plus rice bran substrate to select the mushroom with the best growth. The mycelia of G. lucidum showed the best growth. To investigate the optimal mixing ratio with spent mushroom substrate (SM) and oak sawdust (OS), samples were prepared by mixing SM and OS at ratios of 50%:50%, 60%:40%, and 80%:20% (w/w). Each substrate was then inoculated with G. lucidum. G. lucidum showed the best mycelial growth of 140.0 mm in the substrate with SM and OS mixed at a 60%:40% ratio. It was also found that the substrate with SM and OS mixed at a 60%:40% ratio had the best handling properties. The compressive strength of mycelial materials inoculated with G. lucidum was in the range of 300-302 kgf mm^-1, and the materials were four times stronger than polystyrene materials. These results indicate that substrates comprising spent mushroom substrate mixed with oak sawdust can be successfully upcycled to mycelium-based composite materials using G. lucidum. This represents a sustainable approach.