Earticle

Agaricus bisporus is a functional food and among the most widely cultivated mushrooms in the world. In this study, we analyzed the genetic diversity and population structure of 23 Korean and 42 foreign A. bisporus cultivars using SSR (Simple sequence repeat) markers. Genetic diversity of A. bisporus cultivars was as follows: number of alleles was approximately 13; observed and expected heterozygosity were approximately 0.59 and 0.74, respectively; and polymorphic information content value was about 0.71. A. bisporus cultivars were divided into three groups using distance-based analysis. Genetic diversity of Group 2, which consisted of cultivars from various countries, was high. In addition, model-based subpopulations were divided into two, and the genetic diversity of Pop2 (Population 2), which had many cultivars, was high. The results of this study could be used in a breeding program for A. bisporus, such as the development of new genetic resources and securing diversity.

This study was conducted to investigate the diversity of culture-dependent fungal species in the sawdust media of Lentinula edodes. A total of 405 fungi were isolated from the specimens and identified to belong to 24 genera and 42 species. Among the identified 42 species of fungi, 26.2% belonged to Penicillium sp., 9.5% belonged to Trichoderma sp., and 64.3% belonged to others. Especially, Trichoderma harzianum, which is a causal agent of fungal disease in mushroom, was found on all the farms, and showed the highest frequency among the identified fungi. Community analysis showed that the fungal diversity patterns of the samples were similar to each farm and many kinds of fungi existed in the sawdust media at high levels. These results showed that the management of internal environments would be required for the stable cultivation of Lentinula edodes.

Pleurotus ostreatus No.42, known as the ligninolytic basidiomycetes, showed production of MnP and Lac, but did not show any LiP acitivity in static culture, grown in GPYW liquid medium. Maximum production of MnP (80U/flask) was observed on day 11 of culturing in this medium. Chromatographic purification of MnP included the use of Sepharose CL-6B and Mono-Q. The major MnP isozyme purified by column chromatography was observed to be a 36.4 KDa (single band on SDS PAGE). The 19-amino acid sequence from the N-terminal was determined by protein sequencing to be ATCADGRTTANAACCVLFP. The N-terminal sequence of the major MnP isozyme of P. ostreatus No.42 was found to be the same as a previously reported sequence of an MnP3 isozyme from this fungus.

The edible ectomycorrhizal mushroom Amanita javanica is a valuable species protected by forest law in Korea. However, basic characterization data on its use as an important forest resource has been limited. This study was performed to determine mycelia growth characteristics of the domestically isolated Amanita javanica strain NIFoS 1267 on potato dextrose agar media under diverse culture conditions. Physical factors temperature, pH, and light, as well as chemical factors salts, heavy metals, and pesticides were examined for their effects on the growth of the mushroom strain. The mycelia of A. javanica strain exhibited optimal growth when cultured in dark at 30oC in media with a pH of 5–6. Normal levels of growth were observed in media containing up to 2% saline. At a heavy metal ion content of 50 ppm, mycelial growth was not affected by arsenic ion but was affected by cadmium and lead ions. In the tests performed with two pesticides used in Korean forests, the growth of the mushroom strain was not affected by the presence of abamectin, but was inhibited in media containing acetamiprid, emamectin benzoate, or thiacloprid. These results are expected to facilitate artificial cultivation of A. javanica as a new commercial product.

In this study, smart farm technology was used by farmers cultivating 'CHIKUMASSHU T-011' in order to develop an optimal growth model for the precision cultivation of bottle-grown winter mushroom and the results of the same are mentioned herein. Farmers participating in the experiment used 60 m2 of bed area with 4 rows and 13 columns of shelf shape, 20 horsepower refrigerator, 100T of sandwich panel for insulation, 6 ultrasonic humidifiers, 12 kW of heating, and 20,000 bottles of Flammulina velutipes mushroom spores. The temperature, humidity, and carbon dioxide concentrations, which directly affect the growth of the mushroom, were collected and analyzed from the environmental sensors installed at the winter mushroom cultivation area. The initial temperature was found to be 14.5oC, which was maintained at 14oC to 15oC until the 10th day. In the restriction phase, the initial temperature was 4oC and was maintained between 2oC and 3oC until the 15th day, while during the growth phase, it was maintained between 7.5oC to 9.5oC. Analysis of the humidity data revealed initial humidity to be 100%, which varied between 88% to 98% during primordia formation period. The humidity remained between 77% to 96% until the 15th day, in the restriction phase and between 75% to 83% during the growth phase. The initial carbon dioxide concentration was 3,500 ppm and varied between 3,500 ppm to 6,000 ppm during primordia formation period and was maintained at 6,000 ppm until the 15th day. During the growth phase, the carbon dioxide concentration was found to be over 6,000 ppm. Fruiting body characteristics of 'CHIKUMASSHU T-011' cultivated in the farmhouse were as follows: Pileus diameter of 7.5 mm and thickness of 4.1 mm, stipe thickness of 3.3 mm, and length of 154.2 mm. The number of valid fruiting bodies was 1,048 unit per 1,400 mL bottle, and the individual weight was 0.71 g per unit. The yield of fruiting bodies was 402.8 g per 1,400 mL bottle.

This study was conducted to elucidate the optimal nitrogen content for each variety of oyster mushroom (Pleurotus ostreatus) by investigating the change in the characteristics of fruiting body according to the nitrogen content of the sawdust media, and to use the results as the basic data for cultivation of high quality oyster mushroom. The nitrogen content was adjusted to 1.3%, 1.6%, 1.8% and 2.3%, and at each condition, mycelial growth was observed, which showed that the nitrogen content did not affect the rate of mycelial growth and density substantially. In the investigation of the characteristics of fruiting body, at the 1.8% nitrogen content, Chunchu No.2 showed the pileus diameter of 27 mm, and the stipe diameter and length of 11 mm and 61 mm, respectively, and the measurement of its color values revealed that the brightness of the pileus and the stipe was 31 and 80, respectively, offering the best commercial value, and yielding 25 valid stipes, which was the largest number. Likewise, at the 1.8% nitrogen content, Heuktari also showed the excellent growth characteristics including the pileus diameter of 29 mm and the stipe diameter and length of 10 mm and 68 mm, respectively, and the superb color values of the brightness of 37 at the pileus and 78 at the stipe. Moreover, the number of valid stipes was also found to be the highest with 19. In terms of morphological characteristics such as the pileus diameter and color, Soltari also produced the best mushrooms at the 1.8% nitrogen content and the number of valid stipes was high with 22. In summary, irrespective of varieties of oyster mushroom, high quality products could be cultivated at the nitrogen content of 1.8%.

Currently, cultivation of mushrooms using the Information and Communication Technology (ICT)-based smart farming technique is increasing rapidly. The main environmental factors for growth of mushrooms are temperature, humidity, carbon dioxide (CO2), and light. Among all the mentioned factors, currently, only temperature has been maintained under automatic control. However, humidity and ventilation are controlled using a timer, based on technical experience.Therefore, in this study, a Pleurotus eryngii first-generation smart farm model was set up that can automatically control temperature, humidity, and ventilation. After installing the environmental control system and the monitoring device, the environmental condition of the mushroom cultivation room and the growth of the fruiting bodies were studied. The data thus obtained was compared to that obtained using the conventional cultivation method.In farm A, the temperature during the primordia formation stage was about 17°C , and was maintained at approximately 16°C during the fruiting stage. The humidity was initially maintained at 95%, and the farm was not humidified after the primordia formation stage. There was no sensor for CO2 management, and the system was ventilated as required by observing the shape of the pileus and the stipe. It was observed that, the concentration of CO2 was between 700 and 2,500 ppm during the growth period. The average weight of the mushrooms produced in farm A was 125 g, and the quality was between that of the premium and the first grade.In farm B. The CO2 sensor was in use for measurement purposes only; the system was ventilated as required by observing the shape of the pileus and the stipe. During the growth period, the CO2 concentration was observed to be between 640 and 4,500 ppm. The average weight of the mushrooms produced in farm B was 102 g.These results indicate that the quality of the king oyster mushroom is determined by the environmental conditions, especially by the concentration of CO2. Thus, the data obtained in this study can be used as an optimal smart farm model, where, by improving the environmental control method of farm A, better quality mushrooms were obtained.

Flammulina velutipes, known as winter mushroom or Enokitake, is an important edible mushroom in Korea. In 2017, approximately 28,000 tons of this mushroom were produced in Korea, putting its output at the third place, behind the oyster and king oyster mushrooms. Despite its high production, F. velutipes has the lowest distribution rate of domestic cultivars, estimated to be about 28 percent. To increase the income of farms and provide more options to consumers, we developed a new golden domestic cultivar ‘Auram’. ‘Auram’ was bred by mating two monokaryotic strains isolated from ASI 4103 and ASI 4111. Auram has bright golden, hemispheric shaped caps, and light brown stipes, making it strikingly different from the control. The optimum mycelial growth temperature was 25oC, but Auram mostly displayed higher mycelial growth than the control in a wide range of temperatures. The yield of Auram (257.4 ± 13.5 g) was high, and the period of fruit body growth was also a couple of days ahead in bottle cultivation, compared with the control. Auram received a more favorable evaluation from farms and distributors than the control for its appearance, because the fruit body of Auram had an attractive golden color, and the spotted cap often seen in the control was not observed.

The two most common mushroom species grown in Korea are pearl oyster mushroom (Pleurotus ostreatus) and king oyster mushroom (P. eryngii). In recent years, the production of king oyster mushroom greatly increased due to the automation of the cultivation facilities, and it became a major export mushroom owing to its excellent shelf life. However, the increase in the production of king oyster mushroom led to a decline in its market price; thus, necessitating the development of new mushroom species that could replace king oyster mushroom, to diversify the mushroom market for the benefit of both, the producers and the consumers. The Mushroom division at the National Institute of Horticultural & Herbal Science (NIHHS) reported the development of a new interspecific hybrid between P. ferulae and P. tuoliensis, referred to as ‘Creamy.’ Two parental strains KMCC00430 (Bisan2ho, P. ferulae) and KMCC00461 (P. tuoliensis) were selected based on the results of genetic resource analysis, and their monokaryons were collected. About 1,000 Mon-Mon crosses were performed and 73 of them were selected. Following repeated cultivation tests and strain analyses, we selected strain 7773, which had a bright creamy pileus and a thick straight stipe, and named it ‘Creamy.’ Optimum temperature for mycelial growth of Creamy was 25–30oC, and that for fruiting body growth was 16 oC. The pileus, which had a brighter creamy color, was small in size with a diameter of 61.2 mm. Although it was cultivated in suboptimal conditions, such as low temperature and high CO2 concentration, Creamy was characterized by its straight and smooth stipe. Field production tests and further analyses indicated that the yield of Creamy was 5% higher than that of Baekhwang. It is expected that Creamy, the new interspecific hybrid with a bright creamy pileus and a pleasant flavor, will help create new opportunities for mushroom farmers and diversify the mushroom market.

This study was conducted to prepare healthy vinegars using the mycelia of various mushrooms (Cordyceps militaris, Phellinus baumi, Pleurotus cornucopiae, and Ganoderma lucidum). Analyses of the bioactive components of these vinegars revealed that those prepared using mushroom mycelial cultures on fermented brown rice had increased bioactive component levels compared to those cultured on unfermented brown rice. The highest beta-glucan contents (78.7 mg/g) were found in P. baumi cultures and 0.34mg/g of cordycepin was detected in C. militaris cultures. Regarding the chemical properties of these mushroom mycelia vinegars (MMVs), those prepared using C. militaris and P. cornucopiae cultures showed higher acidity and reduced sugar content. Sensory assessments of C. militaris and P. cornucopiae MMVs yielded scores of 7.3 and 6.6, respectively. Analyses of bioactive components revealed that C. militaris MMV contained high levels of polyphenols and 786 mg/L of cordycepin. P. cornucopiae MMV contained the highest amount of beta-glucan (20.9 mg/g).

In this study, we investigated the effects of pH, temperature, and salt concentration on protease activities in Hypsizygus marmoreus, and the ability of H. marmoreus extract to tenderize beef. In fact, H. marmoreus was shown to have higher protease activity than kiwi fruits. The pH of beef was dose dependently increased with addition of H. marmoreus extract. Cooking loss, cutting strength, and color value (L, a, b) were also dose dependently decreased with addition of H. marmoreus extract. In sensory assessments, H. marmoreus extract dose dependently enhanced perception of tenderness, flavor, and taste. In contrary, use of kiwi fruits as a meat tenderizer decreased positive perception of taste. The protease activitiy of H. marmoreus decreased sharply at pH < 2.0, and temperature > 50 oC. Protease activity was relatively stable in NaCl concentrations ranging from 0–5 M, but incrementally decreased with increasing NaCl. These results suggest that, H. marmoreus extract can improve the texture and taste of beef.

Samples (10 mg/mL) of wild Grifola frondosa aqueous extract and solvent fractions were examined for fibrinolytic, thrombin inhibitory, acetylcholinesterase inhibitory, and antioxidative activities to determine the biological activities. The fibrinolytic activity of the aqueous extract and solvent fractions was 0.93 and 0.73 plasmin units/mL, respectively. The thrombin inhibitory activity of the butanol extract was 79.60%. The chloroform fraction had high acetylcholinesterase inhibitory activity (85.88%). The aqueous extract had low antioxidative activity (39.81%). The aqueous fraction hydrolyzed Bβ subunits of human fibrinogen but did not show any reactivity for the γ form of the human fibrinogen. The findings indicate the potential of wild Grifola frondosa for the development of drugs and bio-functional foods to prevent cardiovascular diseases.

Trametes hirsuta, a white rot fungus, exhibits the ability to degrade synthetic aromatic dyes such as congo red (CR), methylene blue (MB), crystal violet (CV), and remazol brilliant blue R (RBBR). The mycelia of T. hirsuta degraded RBBR and CR more efficiently than CV and MB in the PDB liquid medium (supplemented with 0.01% 4 aromatic dyes). In these mycelia the activities of three ligninolytic enzymes—laccase, manganese peroxidase (MnP), and lignin peroxidase (LiP)—were observed. Among these, laccase was identified to be the major enzyme responsible for the degradation of the four aromatic dyes. The degradation of bisphenol A was also investigated by culturing the mycelia of T. hirsuta in YMG medium supplemented with 100 ppm bisphenol A. The mycelia of T. hirsuta were found to degrade bisphenol A by 71.3, 95.3, and 100 % within incubation periods of 12, 24, and 36 hr, respectively. These mycelia also showed ligninolytic enzyme-like activities including those similar to laccase, MnP, and LiP. Therefore, these results indicate that T. hirsuta could emerge as a potential tool for the remediation of environmental contamination by aromatic dyes and bisphenol A.

The purpose of this study was to identify sector-wise issues that need to be improved for the overall development of the mushroom industry and to prioritize these tasks based on an analysis of the current state of this industry in Korea. To this end, we classified the domestic mushroom industry into four sectors: production, processing, marketing, and export and distribution, and identified major tasks for the improvement of each of these sectors. A total of eleven issues that could be improved were selected, including three each in the production, marketing, and export and distribution sectors, and two in the processing sector. An analytical hierarchy process (AHP) was utilized to identify the issues in each sector that would need to be handled on a priority basis. A questionnaire-based survey was also conducted to gain relevant insights and suggestions from 32 experts in this industry. The present study is significant because it highlights sector-wise priority areas that could be supported by policies and legal measures for the overall development of the mushroom industry.

The objective of this study was to evaluate the antioxidant activity of extracts of Protaetia brevitarsis larvae fed on fermented oak sawdust (FOS) or spent mushroom substrates (SMS, Pleurotus eryngii). Total polyphenol content was 32% higher in extracts of larvae fed on SMS (P. eryngii) (75.33±0.43 mg GAE/g) than in extracts of larvae fed on FOS (57.02±1.73 mg GAE/g). The flavonoid content of extracts of larvae grown on FOS and SMS (P. eryngii) was 24.6±0.28 mg/g and 25.4±0.75 mg/g, respectively. DPPH radical scavenging activity increased in an extract concentration-dependent manner, and the DPPH radical scavenging capacity of the extract of larvae produced on SMS (P. eryngii) was higher than that of the larvae produced on FOS. The reducing power of the larval extracts produced on FOS and SMS (P. eryngii) increased in an extract concentration-dependent manner, but there was no significant difference between them. The extract of larvae fed on SMS (P. eryngii) (66.55±0.99 uM TE/ g) had a higher oxygen radical absorbance capacity (ORAC) than extracts of larvae grown on FOS (76.32±0.48 uM TE/g). The effect of larval extracts on cell proliferation was investigated using a WST-1 (4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]- 1,3-benzene disulfonate) assay on RAW 264.7 cells. When cells were treated with larval extracts produced on FOS and SMS (P. eryngii) at concentrations of 0, 2, 4, 8, 16, 32, 40, and 64 mg/ml, RAW 264.7 cells proliferated at 90% or more. Therefore, larval extracts produced on FOS and SMS (P. eryngii) were not toxic to RAW 264.7 cells.

Sparassis latifolia is a useful medicinal mushroom that has recently gained popularity in Asia. It has a rich flavor and is a good source of nutrients contains a large number of polyphenols for a functional food or dietary supplement. In addition, S. latifolia is rich in beta-glucan and gamma-aminobutyric acid (GABA). These two compounds have been reported to show immune-stimulating and anticancer effects by numerous studies. In this study, four species of lactic acid bacteria (Lactobacillus plantarum subsp. plantarum, L. acidophilus, L. helveticus, and L. delbrueckii subsp. bulgaricus) were used to ferment the fruiting body of S. latifolia. Fermented S. latifolia extracts were found to have a higher polyphenol content and antioxidant activity following fermentation as well as increased protease activity.

Sparassis latifolia is a fungus abundant in β-glucan and amino acids and is highly valued as a medicinal mushroom. Among amino acids, γ-aminobutyric acid (GABA) is a free amino acid and has biological effects, such as increase/decrease of hypertension, improvement of cerebral blood flow, and prevention of dementia. In this study, biological elicitors were used to increase bioactive substances as a biofortification method. Sodium alginate extracted from seaweed (Sargassum horneri, Sargassum fulvellum, Sargassum fusiforme) were used as the elicitor. The levels of β-glucan and GABA in the mycelium and fruiting body grown by adding the elicitor to the medium were investigated. Addition of sodium alginate positively affected GABA production and negatively affected the β-glucan production in these fungi. Sodium alginates extracted from S. fulvellum induced the highest increase in GABA in the mycelium and fruiting bodies. Moreover, we investigated the effects of the extracts from mycelium and fruiting bodies on dendrite development in primary cortical neurons. We found that the extract from the fruiting bodies of sodium alginate treated fungi with increased levels of GABA inhibited the dendrite outgrowth of excitatory neurons, but not inhibitory neurons.