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Mycorrhiza refers to the association between a plant and a fungus colonizing the cortical tissue of the plant’s roots during periods of active plant growth. The benefits afforded by plants from mycorrhizal symbioses can be characterized either agronomically, based on increased growth and yield, or ecologically, based on improved fitness (i.e., reproductive ability). In either case, the benefit accrues primarily because mycorrhizal fungi form a critical linkage between plant roots and the soil. The soilborne or extramatrical hyphae take up nutrients from the soil solution and transport them to the root. This mycorrhizaemediated mechanism increases the effective absorptive surface area of the plant. There are seven major types of mycorrhizae along with mycoheterotrophy: endomycorrhizae (arbuscular mycorrhizae, AM), ectomycorrhizae (EM), ectendomycorrhizae, monotropoid, arbutoid, orchid, and ericoid. Endomycorrhizal fungi form arbuscules or highly branched structures within root cortical cells, giving rise to arbuscular mycorrhiza, which may produce extensive extramatrical hyphae and significantly increase phosphorus inflow rates in the plants they colonize. Ectomycorrhizal fungi may produce large quantities of hyphae on the root and in the soil; these hyphae play a role in absorption and translocation of inorganic nutrients and water, and also release nutrients from litter layers by producing enzymes involved in mineralization of organic matters. Over 4,000 fungal species, primarily belonging to Basidiomycotina and to a lesser extent Ascomycotina, are able to form ectomycorrhizae. Many of these fungi produce various mushrooms on the forest floor that are traded at a high price. In this paper, we discuss the benefits, nutrient cycles, and artificial cultivation of mycorrhizae in Korea.

Light is an important factor for cordycepin production in Cordyceps militaris. We investigated the effects of different light-emitting diode (LED) conditions including various LED wavelengths and their combinations on cordycepin production in Cordyceps militaris cultivated in submerged culture. The results of our study showed that the combinations of LED wavelengths were more beneficial than single LED sources for cordycepin production. Among the three tested wavelength combinations, the greatest effects for cordycepin production were observed for the red:blue light combination at the wavelength ratio of 5:5 or 3:7. The optimal culture conditions were 19.2278 h/day of illumination time; 9.19497 g/50 mL of glucose content in the media; and 53.112 h of cultivation time. Our model predicted a maximum yield of 2860.01 μg/mL cordycepin. Finally, to verify the calculated maximum, we performed experiments in the culture media representing the obtained optimum combination and the cordycepin yield of 2412.5 μg/mL.

This study was conducted to determine the antioxidant, nitrite scavenging, melanin tyrosinase inhibitory, and melanogenesis inhibitory activities of fermented Coix lacryma-jobi L. var. mayuen Stapf. by Hericium erinaceum (Bull.: Fr.) mycelial hot water extract (FCLHE). Additionally, we analyzed β-glucan and ergosterol contents in FCLHE and C. lacryma-jobi hot water extract (CLHE). The ergosterol and β-glucan contents in FCLHE were 740.2 mg% and 245.3 mg%, respectively, whereas these components were not detected in CLHE. FCLHE showed higher cell viability than CLHE. When B16F10 cells were treated with 500 μg/mL each of CLHE and FCLHE, the FCLHE treated cells produced 8.9 uM nitric oxide (NO), which was lower than that produced by CLHE treated cells (10.6 uM). The FCLHE treated cells showed significantly greater tyrosinase inhibition and melanin production at all tested concentrations than when compared to the CLHE treated group. Antioxidant parameters such as DPPH and ABTS radical scavenging activities were higher in FCLHE than in CLHE. These results suggest that FCLHE can be used as a raw material for functional foods, for food additives, and in the cosmetic industry.

P. linteus (Korea Sanghwang, PLKS) and P. baumii (Jangsoo Sangwhang, PBJS) were artificially cultivated under the same conditions. Fruiting bodies were extracted using 70% methanol, 60% ethanol, and hot water. Phenol and flavonoid contents were optimally extracted using 60% ethanol. Antioxidant activities of 60% ethanol extracts from fruiting bodies and mycelia from each Sanghwang mushroom species were measured using DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azino-bis (3- ethylbisthiazoline-6-sulfonic acid) radical scavenging activities, and FRAP (ferric reducing antioxidant power). The antioxidant activities of fruiting bodies were relatively higher in comparison to those of mycelial samples. In high performance liquid chromatography (HPLC) analysis, styrylpyrone-class poly phenolic compounds, davallialactone, hispidin, hypholomine B, and inoscavin A were detected in fruiting body samples of two Sanghwang mushroom species, but not in their mycelial samples.

The antioxidant activities and β-glucan contents of hot-water extracts of the eggs and fruiting bodies of Phallus indusiatus were investigated using different drying methods, and the amino acid contents as nutritional components of the eggs and fruiting bodies of P. indusiatus were analyzed. DPPH radical scavenging and nitrite scavenging activities of hot-water extracts of the eggs of P. indusiatus obtained after hot-air drying were 59.4% and 15.6%, respectively, at 1 mg/ml concentrations, which showed higher activities than those of freeze dried samples. Total polyphenol and β-glucan contents in hot-air-dried hot-water extracts of the eggs of P. indusiatus were 8.25 mg GAE/g and 45.9%, respectively, which were the highest among all samples. Additionally, 17 amino acids were detected from the hot-water extracts of the eggs and fruiting bodies of P. indusiatus, and the amino acid contents were higher in the eggs than in the fruiting bodies. Cysteine, phenylalanine, and glutamic acid were the most abundant essential and non-essential amino acids in the analyzed extracts. The results of this study showed that the physiological activities of the antioxidants from P. indusiatus, well known as wild edible mushroom, were greater when extracted from the dried samples. Further, the amino acid contents were higher in the egg extracts than in the extracts from the fruiting bodies of P. indusiatus.

Termitomyces albuminosus has been recognized to have the best mushrooms in China, in terms of taste and aroma. The efficacy of these mushrooms has been recorded in the botanical list. However, research on the development of their artificial culture methods is necessary. In this study, we prepared an organic solvent extract and a hot water extract to understand the development of compounds and functional foods with antioxidant and anti-inflammatory activities. The IC50 value of DPPH radical scavenging activity of the hot water extract (TA4) was 1.5 mg/mL and the IC50 value of the MeOH fraction (TA2) was 1.93 mg/mL. The anti-inflammatory activity was investigated by the inhibition of NO production. EtOAc fraction (TA1) is a crude extract, but 79% of NO production was inhibited at 100 μg/mL. NO was not produced at 200 μg/mL. TA1-5-6, from TA1 inhibited NO production by 15% as compared to the positive control at 15 μg/mL, and completely inhibited NO production at 30 μg/mL. No cytotoxicity was observed at 50 μg/mL. TA2-1-5 from the MeOH fraction (TA2) inhibited more than 75% of NO production at 30 μg/mL; cytotoxicity was very low even at 50 μg/mL. In conclusion, by selective solvent selection, it was possible to manufacture an extract with no cytotoxicity and excellent biological activities. Furthermore, the extracts showed potential for developing various functional foods and drugs.

The aims of this study were to investigate the biological activities and amino acid contents of fermentation ethanol and sodium extracts from five edible mushrooms (Pleurotus eryngii, Pleurotus ostreatus, Flammulina velutipes, Lentinula edodes, and Agaricus bisporus). DPPH radical scavenging activities in 30% fermentation ethanol extracts of P. eryngii and P. ostreatus were significantly higher than those in sodium extracts (p<0.05). Nitrite scavenging activities were also higher in the 30% fermentation ethanol extracts of P. eryngii and P. ostreatus. The total polyphenol contents of P. eryngii, P. ostreatus, and F. velutipes were high in 70% fermentation ethanol extracts. The analysis of amino acids revealed that the 70% fermentation ethanol extract of P. eryngii had the highest content of total amino acids, with higher phenylalanine, leucine, isoleucine, valine, and tyrosine contents higher than the other extracts. In all the extracts of P. ostreatus, glutamic acid was the most abundant amino acid. The 5% NaCl and 30% fermentation ethanol extracts of F. velutipes contained abundant glutamic acid, alanine, and proline. Glutamic acid was the most abundant amino acid in the 70% and 30% fermentation ethanol extracts of L. edodes. In the 5% NaCl extracts of A. bisporus, glutamic acid and alanine were abundant. Thus, maximum biological and nutritional ingredients can be extracted using the optimal solvents for each type of mushroom.

The present study aimed to investigate the biological activities and nutritional contents of extracts from three types of edible mushrooms (Pleurotus ostreatus, P. eryngii, and Hericium erinaceus) following different roasting treatments. Roasting by a household multi-oven (HR60) decreased the total polyphenol contents, as well as DPPH radical scavenging and nitrite scavenging activities compared with the fresh samples, and no significant difference was observed between the different roasting times. As a result of rotary drum roasting (CR) treatment, we could observe a decrease in the DPPH radical scavenging activity in all roasted mushroom samples compared with the fresh samples, whereas nitrite scavenging activity increased in roasted P. eryngii and H. erinaceus. Additionally, total polyphenol contents increased significantly in roasted H. erinaceus. In each roasted sample dried by HR60 and CR, the amount of palatable-taste amino acids (e.g., glutamic acid) and sweet-taste amino acids, including glycine, serine, alanine, and threonine, increased in P. ostreatus, whereas the amount of bitter amino acids , including leucine, isoleucine, histidine, valine, and methionine, decreased compared with the fresh samples. In P. eryngii and H. erinaceus samples, we also observed an increase in the amount of palatable and sweet-taste amino acids upon the roasting treatments; however, the amount of bitter amino acids increased simultaneously following the roasting treatments. These results suggest that CR treatment is more effective in increasing the biological activities and nutritional contents, such as palatable and sweet-taste amino acids, compared with HR60 treatment.

During the monitoring of fungal pests in 2016 and 2017, Acrodontium crateriforme, Naganishia friedmannii, Pestalotiopsis trachicarpicola, Penicillium wollemiicola, and Trichoderma thailandicum were isolated from indoor air, mushroom flies (Phytosciara flavipes), and media materials in the cultivation houses of oak wood mushroom (Lentinula edodes) located in Seocheon, Jangheung, Buyeo, and Yeoju, Korea. These fungal species were identified based on their morphological characteristics after their growth on PDA and subsequent molecular analyses of the 26S rDNA, 28S rDNA, β-tubulin gene, and translation elongation factor 1-α gene using PCR amplification and nucleotide sequencing were performed. The results showed that these fungi were previously undocumented in Korea. This study reports descriptions of their taxonomical and known properties.

In this study, we determined the effect of different concentrations of Cd on the growth of Pleurotus ostreatus mycelia, which was confirmed using PDA, PDB, and a column test. The efficacy of treatment was evaluated using Cd at two concentrations, 10 ppm and 100 ppm. The extent of mycelial growth on PDA and PDB was similar to that observed in the untreated groups and those treated with 10 ppm Cd. However, it was found that the mycelial growth was suppressed in a system treated with Cd at concentrations of 100 ppm. Moreover, the extent of mycelial growth observed upon conducting a column test was similar to that obtained using PDA and PDB. When the composition of free amino acids in PDB was determined, their levels in the group treated with 100 ppm Cd were found to be similar to those of the control. However, the amounts of 15 amino acids in the group treated with 10 ppm of Cd had increased compared to those detected in the control.

Wild-type isolates of H. erinaceus were collected from different geographical areas of Korea. Nineteen isolates were cultured on mushroom substrate for producing fruiting bodies. Of these, 14 isolates formed pinheads and fruiting bodies on the substrate. The morphological and cultivation characteristics of fruiting bodies were categorized by pinheading, fruit body formation, spine types, fresh weights, and colors. Microstructures, including spines, spores, and basidia on the fruiting bodies were observed using scanning electron microscopy. The H. erinaceus isolates demonstrated different PCR polymorphisms produced by universal fungal primers (UFPs) and were classified into four groups based on their high genetic diversity.

This study was carried out to develop a method for cultivation of Lentinula edodes that would reduce both labor and waste. Cultural characteristics were studied, and mushroom yields were estimated to identify the most suitable method to culture L. edodes, using bottles and boxes. Among these, box cultivation with 7 kg of substrate had 40 days of browning period and the maximum yield of 945 g fruiting body; its biological efficiency was 32.7%. In contrast, box cultivation after pre-culture, and the bottle cultivation were found to be unsuitable for the production of L. edodes, due to long periods of browning, and low yields with poor quality, respectively. Further studies on box cultivation of L. edodes are necessary for commercial application of this method.

The trade deficit in mushrooms has continued to increase in recent years. This study explored major issues and challenges faced by the mushroom industry to increase export, and to prioritize the current issues and challenges based on their relative importance. 11 major issues and challenges in the mushroom industry were highlighted in focus group interviews. Bestworst scaling analysis prioritized these major issues and challenges, and questionnaire surveys were completed by 31 mushroom industry experts. The results revealed that strengthening the mushroom quality and price competitiveness were the main priorities, followed sequentially by a diversification of the overseas export markets and stabilization of the domestic mushroom price.

Eight morel mushroom species were collected from Korea and other countries. The culture characteristics, genetic relationships, and beta-glucan content of the strains were analyzed. The mycelia of Morchella species exhibited optimal growth when cultured in dark at 25 °C in media with pH 7. The mycelia had a distinctive mycelial scent and characteristically changed color, being white initially, and then turning dark yellow to dark brown as it grew. The mycelia were classified into five types based on morphology. The isolates were identified as Morchella conica, two M. sextelata, M. importuna, M. esculenta, and three M. crassipes, based on ITS-rDNA sequences. PCR polymorphisms were variably produced within Morchella spp. using Universal Fungal Fingerprinting Primers (UFPF) and classified into four groups at the intra and inter species level. The strains, KMCC04971 and KMCC04407, showed the same banding pattern as M. conica and M. sextelata, respectively; however, these results were different from those of ITS analysis. Glucan content analysis by strain showed that the KMCC 04973 strain of M. importuna had the highest alpha- and beta-glucan content, at 16.4 g and 33.1 g per 100 g, respectively.

Fifteen species of wild mushrooms, which are classified as edible, medicinal, poisonous, or unknown types, were analyzed for their free amino acid contents. The average total amino acid content was 1,120.0 mg/kg in the edible type, 1,037.8 mg/kg in the medicinal type, and 1,010.8 mg/kg in the poisonous or unknown type, respectively. The edible type wild mushrooms showed the highest average content of total essential amino acids; conversely, the poisonous or unknown type showed the lowest content. Leucopaxillus giganteus (OK811) showed the highest total amino acid (1,212.4 mg/kg) and essential amino acid (490.2 mg/kg) contents among edible type, while Pycnoporus sanguineus (OK1071) showed the highest total amino acid (1,233.7 mg/kg) and essential amino acid (412.8 mg/kg) contents among the medicinal type. Among the poisonous or unknown type, Hypholoma fasciculare (OK826) showed the highest total amino acid (1,223.4 mg/kg) and essential amino acid (442.8 mg/kg) contents. The amino acid contents of wild mushrooms are fundamental data for the screening of useful genetic resources with nutritionally superior properties.

This study was conducted to investigate the effect of post-harvest CO2 treatment on the quality of the ‘Gonji-7ho’ oyster mushroom. The harvested mushrooms were pre-cooled at 3oC for 1 day and placed in a gas-tight chamber with 0%, 30%, or 50% of CO2 concentration for 3 hours at 3oC. Next, 400 g of the oyster mushroom sample was packaged into 20-μm thick oriented polypropylene (OPP) film bags and stored at 4oC for 21 days. Treatment with 30% of CO2 treatment maintained the highest stipe firmness of the oyster mushrooms during storage. The stipe lightness (CIE L*) was the highest at 14 and 21 days, while the stipe yellowness (CIE b*) was the lowest at 2 and 7 days of storage. Therefore, we concluded that the 30% CO2 treatment maintained the overall visual quality of the ‘Gonji-7ho’ oyster mushroom until 17 days of storage at 3oC. Our results suggest that the shelf life of ‘Gonji-7ho’ oyster mushroom could be extended by the postharvest application of 30% CO2 for 3 hours during low temperature storage.

This study was conducted to provide basic data for setting a standard medium for winter mushroom cultivation. Investigation of medium composition in winter mushroom farms in Korea revealed that the types of medium used for each farm were slightly different and that the mixing ratio of the medium also varied. All farmers used corncob, rice bran, and beet pulp as the main media, and calcium carbonate and ground oyster shells were used at 1.0~3.8% to adjust the pH of the medium. Analysis of the physicochemical properties of the mixed media showed nitrogen content of 1.28~1.52%, carbon content of 45.7~48.5%, and C/N ratio of 30.7~37.9. The content of inorganic components was significantly different in each farm, depending on the type and amount of minerals in the mixed medium. Mycelial growth was the fastest at Farm 2, reaching 6.5 cm within 34 days of culture, followed by Farm 4 at 5.7 cm, whereas Farm 1, 3, and 5 showed similar growth. Mycelial density was high without any significant difference between farms. Survey of yield according to medium composition in each farm showed the highest yield in Farm 2 at 173.4 g/bottle, followed by Farm 1 at 168.4 g/bottle, whereas Farm 3 and 4 showed similar yield. However, Farm 4 had the lowest yield at 145.4 g/bottle. Therefore, mushroom yield was different depending on the medium composition in the farm, and thus selection of a medium that can be used universally in multiple mushroom farms was considered possible.