Earticle

The oak mushroom (Lentinula edodes) is a popular edible mushroom that has long been cultivated and eaten throughout Northeast Asia (including Korea). Its taste and flavor are unique. Oak mushrooms are cultivated on logs and in sawdust. The cultivation period on logs is 4–5 years, while the cultivation period in sawdust is 6 months, which is rapidly driving a shift from log to sawdust based cultivation. In particular, the Sanjo 701ho cultivar of L. edodes is a mid-range to hightemperature variety that is widely known for its suitability for summer cultivation on sawdust in Korea. This study summarizes new developments and achievements in the oak mushroom industry in Korea, and details the cultivation history of Sanjo 701ho, its culturing characteristics, various demonstration tests, and the expansion of domestic varieties.

Pleurotus djamor var. roseus is an edible mushroom isolated from the wild and cultivated on paddy straw substrates. The present study was carried out to compare the nutritional composition and antioxidant properties of P. djamor var. roseus at different growth stages (primordia, basidiomata, and mycelia). The protein content was is in the range of 31.48 to 35.50 g/100g dw. The crude fiber content ranged from 8.0 to 14.60 g, and that of total carbohydrates ranged from 44.75 to 48.90 g. Sodium, magnesium, and calcium reached the maximum levels in basidiomata, and selenium was detected in basidiomata and mycelia (0.47 - 0.22 mg/Kg). The amino acid profile showed that all essential and nonessential amino acids and glycine showed maximum levels in basidiomata and 15.98 ± 0.01 g/100g. The fatty acid profile showed the presence of saturated and unsaturated fatty acids; the unsaturated fatty acid content was maximum in all of the samples, ranging from 76 – 40.41%. The total phenol and flavonoid contents as well as the scavenging (DPPH), ferric thiocyanate (FTC), and thiobarbituric acid (TBA) activities in the context of methanol and water extracts from primordia, basidiomata, and mycelium were determined. Among them, basidiomata and mycelial methanol extracts exhibited significant antioxidant activity. Overall, these findings show that P. djamor var. roseus can be used as a functional food for daily consumption.

Mushrooms growing in the Wolchulsan National Park were surveyed from April to October 2018. As a result of this survey, 2 divisions, 9 classes, 24 orders, 71 families, 177 genera, and 407 species were found. Among them, 3 classes, 16 orders, 55 families, 150 genera, and 370 species belonged to Basidiomycota, while 6 classes, 8 orders, 16 families, 27 genera, and 37 species belonged to Ascomycota. The species richness was the highest in September at the altitudes between ~100 and 200 m. Among the investigated sites, the most diverse species occurred in the Gyeongpodae area. In this survey we found, Macrolepiota procera, Suillus bovinus, and Amanita pantherina, all of which have been known as climate-sensitive biological indicator species (CBIS). Based on the DNA sequence analyses, Craterellus parvogriseus was confirmed as a new record for Korea.

Burkholderia contaminans PSB-A and Burkholderia ambifaria PSB-B were isolated from button mushroom bed to estimate their phosphate solubility. The phosphate-solubilizing abilities of these strains were assessed by measuring the phosphorus content in a single and co-inoculation medium for 7 days. The co-inoculation of these two strains released the highest content of soluble phosphorus (166.3 μg mL-1) into the medium, followed by single inoculation of B. contaminans PSB-A (143.73 μg mL-1) and B. ambifaria PSB-B (127.1 μg mL-1). The highest pH reduction, organic acid production, and glucose consumption were also observed in the co-inoculation medium. According to the plant growth promotion bioassay, coinoculation enhanced the growth of romaine lettuce much more than the single inoculation (20.4% for leaf widths and 16.6% for root lengths). Although no significant difference was noted between single and co-inoculation of bacterial strains in terms of phosphorous release and plant growth, co-inoculation of PSB may have a beneficial effect on crop growth due to a synergistic effect between the strains.

We undertook a breeding program to produce a white button mushroom cultivar with high temperature tolerance in preparation for climate change. The results were as follows. The strains KMCC00540, KMCC00591, and KMCC00643 were selected, and homokaryons were selected and hybrids were identified with ISSR and SSR markers, respectively. The selected hybrids were cultivated in three repetitions at a temperature of 20-25 °C and a humidity of 80% or higher. The variation in agricultural traits and fruiting body characteristics was least in the Abs4-2016-121 strain. This line is a hybrid of KMCC00591 and KMCC00875, and field experiments at Gyeongju and Buyeo farms found that the Abs4-2016-121 line has high fruiting body with hardness and delayed opening of pileus at high temperatures, so it was bred as a high-temperature cultivar named ‘Hadam’.

This study was carried out to compare the growth characteristics, biological activities, β-glucan contents, sugar contents, and amino acid contents of 14 strains of Ganoderma spp. Among the 14 strains of Ganoderma spp., KMCC02960 (G. meredithae) and KMCC02932 (G. tropicum) showed excellent growth characteristics such as those with respect to the size and yield of fruiting bodies. The highest 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity was observed in KMCC02932 (G. tropicum). The nitrite scavenging activities of KMCC02824 (G. lucidum) and KMCC02852 (G. neo-japonicum) were higher than those of the other strains. The total polyphenol contents of the extracts from KMCC02824 (G. lucidum) and KMCC02852 (G. neo-japonicum) were higher than those of the other strains. KMCC03018 (G. lingzhi) showed the highest β-glucan content of 33.4%. In an analysis of the 4 types of monosaccharides, 2 types of disaccharides, and 4 types of sugar alcohols, only KMCC02996 (G. weberianum) and KMCC03018 (G. lingzhi) were commonly detected out of the 14 strains of Ganoderma spp. Eighteen amino acids, including eight essential amino acids, were identified: the highest total amino acids and total essential amino acids were found in KMCC02932 (G. tropicum), which had the highest levels of tyrosine and phenylalanine. Although the contents of amino acids differed by strain, cysteine, tyrosine, and phenylalanine were the most abundant amino acids in the analyzed extracts.

The physicochemical characteristics and antioxidant activities of Lentinula edodes cultivated with liquid spawn were compared according to the harvest cycle (1–3 cycles). There was no significant difference in moisture content. The crude lipid and crude protein contents tended to decrease according to harvest cycle. The content of β-glucan was the highest in mushrooms after one cycle. The β-glucan content in cycles 2 and 3 was 68.5% and 62.3% that of the content after cycle 1, respectively. Mineral content in the pileus and stipe was similar. The mineral content was highest in the pileus after two cycles. Composition and contents of free amino acids tended to decrease according to the harvest cycle. Contents of essential amino acids were higher in mushroom after one cycle. Total phenol content was highest in the pileus (31.96 mg/ 100 g) and the stipe (21.10 mg/100 g) after one cycle and tended to decrease with subsequent cycles. The flavonoid content was 11.13 mg/100 g after one cycle and significantly decreased according to the harvest cycle. Antioxidant activities were also highest after one cycle and significantly decreased according to the harvest cycle. When compared to L. edodes cultured for one cycle, L. edodes cultivated with liquid spawn for three cycles was considered to have similar marketability in terms of quality characteristics.

The aim of this study was to investigate the biological activity of extracts obtained from the mycelium, sclerotium, and fruiting body of Wolfiporia cocos using different extraction solvents (hot water, 70% ethanol, and 70% methanol). Among the three developmental stages, the mycelium extracts showed the highest DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, ferric reducing antioxidant power (FRAP), nitrite scavenging activity, and total polyphenolic content. Among the extraction solvents in the context of the W. cocos mycelium, the DPPH radical scavenging activity, FRAP, and total polyphenol content in the hot-water extracts were significantly higher than those in the other extracts. In the case of the sclerotium, the reducing power, nitrite scavenging activity, and total polyphenol content were significantly higher in 70% ethanolic extracts. The fruiting body showed the highest DPPH radical scavenging activity, reducing power, nitrite scavenging activity, and total polyphenol content in the context of hot-water extraction. Moreover, the β-glucan content was significantly higher in the sclerotium versus the mycelium or fruiting body. The total amino acid and total essential amino acid contents were remarkably higher in the mycelium and fruiting body than in the sclerotium; of note, and arginine (Arg) and phenylalanine (Phe) were highly detected among the amino acid components.

Grifola frondosa is a promising new kind of cultivated mushroom owing to its excellent taste and functionality. However, more research is required to determine its value. In this study, the effects of pretreating Grifola frondosa tea by drying, steaming, and warming, on quality characteristics and antioxidant activities were analyzed. There was no difference in sugar, soluble solid, and nitrogen content between dried and steamed tea. The color of the warm pretreated tea was the darkest, and the amino acid content was 462.9 mg/L, which was 1.8 times higher than that of the other pretreatments. Moreover, the warm pretreated tea had the highest total polyphenol and flavonoid content, 14.6 mg/g and 2.2 mg/g, respectively. DPPH and ABTS radical scavenging activities significantly increased with the increase of phenolic compounds. Warming pre-treatment slightly increased the taste preference to 7.0. In conclusion, warming Grifola frondosa before drying was confirmed to improve the extraction of nutrients, antioxidants, and taste preference.

Phellinus baumii, a white-rot fungus, has been used for centuries as folk medicine in China, Japan, and Korea. This study aimed to evaluate the in vitro anti-diabetic, and anti-cholinesterase, and in vivo anti-inflammatory effects of the fruiting bodies of P. baumii. The methanol (ME) and hot water (HE) extracts (2.0 mg/mL) of P. baumii fruiting bodies suppressed α-amylase activity, exactly 61.33%, and 65.00%, respectively; of note, acarbose, the positive control, inhibited 93.33% of the α-amylase activity. Moreover, the ME and HE (2.0 mg/mL) inhibited 89.67% and 91.00%, respectively, of the activity of α-glucosidase activity, whereas the same concentration of acarbose suppressed 84.67% of the α-glucosidase activity. The ME and HE (1.0 mg/ mL) also inhibited 96.05% and 94.58%, respectively, of the acetylcholinesterase (AChE) activity; galanthamine, the positive control, led to an inhibition of 81.12%. The butyrylcholinesterase (BChE) activity was also inhibited by ME and HE (1.0 mg/mL; 91.05% and 82.27%, respectively); of note, the same concentration of galanthamine suppressed 81.12% of the BChE activity. The production of NO in LPS-induced RAW 264.7 macrophages was significantly suppressed by both ME and HE treatments. Importantly, the carrageenan-activated rat hind-paw edema was significantly reduced 2–6 h after ME administration (50 mg/mL). Taken together, the results suggest that the fruiting bodies of P. baumii have α-amylase, α-glucosidase, α-cholinesterase, and antiinflammatory activities, and, therefore, may be good natural sources for the promotion of human health.

This study aimed to assess the feasibility of composting spent mushroom substrate (SMS) materials of Lentinula edodes (Le), Hericium erinaceus (He), and Pleurotus ostreatus (Po). The different SMSs were composted for 7 to 10 days at high temperatures over 50oC; the composting procedure was completed in 30 days. A maturity test was conducted using the radish seed germination index and CoMMe-100. The composted SMS (CSMS) from Le and He showed gemination indices of 130% and 81%, respectively, that satisfied the criteria of maturity standard (gemination index over 70%) and the CoMMe-100 analysis. The physicochemical changes of CSMSs included an increase in the pH range from 4–5 to 6–7, slight reduction in the EC to 1–1.4 dS/m, and an organic content of 36.9% in LeCSMS. In LeCSMS, the contents of N, P, and K were 1.2%, 2.3%, and 0.77%, respectively, and heavy metals were detected below the standard value in all CSMSs; the Ca and Mg contents in the CSMSs were increased from 30% to 60% when compared to those in the SMSs. The C/N ratio (from 26–33) in LeSMS and HeSMS decreased to 15.3–15.9 in CSMSs. The growth effect of LeCSMS treatment on pepper seedlings was 60% higher than that in the control groups , one of which was treated with commercial organic compost; the former showed a superior growth effect on the leaf width, leaf length, and leaf number compared to other control groups. In conclusion, LeCSMS and HeCSMS could be utilized as compost resources capable of efficient soil amendment and plant growth promotion.

This study was conducted to investigate the characteristics of the medium used on the composting step, comparing the excavator agitator with the self-propelled turner. The temperature of the outdoor composting medium tended to increase rapidly after flipping in the turner. The late composting medium temperature was maintained at the excavator treatment area (farm practice), and the late composting effect progressed. During the field composting stage, various microorganisms such as Bacillus spp., Actinomycetes, fluorescent Pseudomonas spp., and filamentous fungi were distributed in the medium, and the density of aerobic bacteria involved in the decomposition of the medium was increased. Under high-temperature composting conditions, blue fungi, and mesophilic actinomycetes were inhibited or killed. Thermophilic actinomycetes, which play an important role in decomposing organic matter, showed higher densities than those observed in farm practices in the self-propelled turner process. The length of rice straw was slightly shorter when the self-propelled turner was used, and the water content did not show any significant difference between treatments. The a and b values tended to increase as the inverter was turned over. The CN ratio of the composting broth was lowered from 23.1 to 16.2 for the 5th turnover in the context of farming practices, and from 23.3 to 16.9 in the context of the self-propelled turner. The yield of each treatment was increased by 20% in 1 period, 28% in 2 periods, and 26% in 3 periods; the overall yield was 23%.

The production and consumption of fresh mushrooms has been increasing worldwide because of the health benefits of the dietary fiber and antioxidant components. Using 142 valid patents from five countries, trends in postharvest technology patents were analyzed and categorized into packaging and storage. The patent portfolio index showed that the number of patents for postharvest storage technology is growing, with the number of both approved patents and applications increasing from the third to the fourth time period, albeit the overall growth pattern suggests that this is a recovery stage. Notably, Korea showed an increasing trend in the number of patent applications related to postharvest technologies, although the number of patent applications was smaller than that of China. Our study describes trends in technical patents that support the performance of new postharvest projects of fresh mushrooms.