Earticle

Mushroom consumption causes changes in the immune system and gut microbiota via the actions of mushroom probiotic components. β-Glucan structure-related substances suppress secretion of inflammatory mediators, and induce macrophage activation, enhancing immunity and immune function. Substances other than directly useful components can be metabolized into short-chain fatty acids by gut microbiota. These short-chain fatty acids can then induce immunity, alleviating various diseases. Substances used to stimulate growth of health-promoting gut bacteria, thereby changing the gut microbiota community are defined to be probiotics. Probiotic altered intestinal microflora can prevent various types of bacterial infection from external sources, and can help to maintain immune system balance, thus preventing diseases. Research into beneficial components of Pleurotus eryngii, Lentinula edodes, Pleurotus ostreatus, Flammulina velutipes, Auricularia auricula-judae, and Agaricus bisporus, which are frequently consumed in Korea, changes in microbiota, changes in short-chain fatty acids, and correlations between consumption and health contribute to our understanding of the effects of dietary mushrooms on disease prevention and mitigation.

In this study, we investigated the effect of solid culture medium on the production of cordycepin in Cordyceps militaris. The regression equation was expressed as follows: Y1= 755.3-58.6625X1+4.79432E-14X2-46.6625X3-5.66269E-14X1X2- 0.025X1X3+1.62475E-14X2X3-160.6625X1 2+0.0125X2 2-206.9625X3 2, where, Y represents the value of cordycepin content (μg/g), X1 corresponds to the weight of M. alternatus in solid culture medium (g/bottle), X2 to the water content of the solid culture medium (%), and X3 to the culture period (day). The solid culture medium was optimized using the response surface methodology, and the optimal medium composition was as follows: the weight of M. alternatus in solid culture medium and water content were 16.2% and 100.7% (20.14 mL water/20 g solid culture medium), respectively, with a culture period of 39 days. Under these conditions, the cordycepin content of the fruiting bodies reached 150.0 μg/g (actual value). The supplementation of M. alternatus in solid culture for improved cordycepin content of C. militaris seems to be a promising alternative to wild and solid cultivation.

A diverse group of plant-growth promoting bacteria were isolated in button mushroom (Agaricus bisporus) media to investigate the plant-growth promoting traits of compounds including indole acetic acid (IAA), ammonia, 1-aminocyclopropane-1- carboxylic acid deaminase, siderophore, and hydrogen cyanide. Twenty-one bacterial strains showing positive effects for all the test traits were selected and classified to confirm bacterial diversity in the media habitat. Plant-growth promoting traits of the isolates were also assessed. All strains produced IAA ranging from 20 μg/mL to 250 μg/mL. Most of the isolates produced more than 80% siderophore. Four strains (Pantoea sp., PSB-08, Bacillus sp., PSB-13, Pseudomonas sp., PSB-17, and Enterobacter sp., PSB-21) showed outstanding performances for all the tested traits. In a bioassay of these four strains using mung bean plant, the best growth performances (23.16 cm, 22.98 cm, 2.27 g/plant, and 1.83 g/plant for shoot length, root length, shoot dry weight, and root dry weight, respectively) were obtained from the plants co-inoculated with Bacillus sp., PSB-13. The resultant data indicate that button mushroom media have got a diverse group of bacteria with plant growth promoting abilities. Thus, the media could be a good recycling resource for using to an effective bio-fertilizer.

Mushroom-derived polysaccharides, which are the primary bioactive constituents, are beneficial for human health. Polysaccharides have immuno-modulation, antitumor, and antioxidant properties. Additionally, they have antiviral properties and protect against chronic radiation stress. In this study, high yield water-soluble polysaccharides were obtained from Pleurotus djamor var. roseus basidiocarps. The crude polysaccharide (CP) was extracted sequentially by hot water and ethanol precipitation. The yield of the brown CPs was 5.6% dw. Diethylaminoethyl cellulose and Sepharose-6B column chromatography of CPs generated several fractions. Total glucan content was determined in all the fractions. The F1 fraction displayed the highest sugar content and was considered as a purified polysaccharide (PP). The total glucan and β-glucan content in the four fractions ranged between 76.85-2.95% and 75.08-1.46%, respectively. The yield of the PPs was 300 mg, and it was obtained as a white powder. The PPs were characterized by Fourier-transform infrared spectroscopy (FTIR) and thin-layer chromatography. The FTIR spectral details confirmed the presence of a xylopentose polysaccharide. The antioxidant activity of the PPs was evaluated using in vitro 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging assay and superoxide radical scavenging assay. The PPs showed strong DPPH free radical and superoxide anion radical scavenging activities in a dose-dependent manner. Purified PPs free of phenolics, protein, and carbohydrates were mainly responsible for the radical scavenging activity. The data suggest the potential of PPs as natural antioxidants.

Anti-melanogenesis and skin anti-wrinkle effects of methanol (ME) and hot water (HE) extracts from the fruiting bodies of Ganoderma applanatum were investigated in this study. The total phenolic contents of the ME and HE of the mushroom were 11.68 and 3.15 μg GAEs/mg, respectively, whereas the total flavonoid contents of the ME and HE were 21.82 and 2.69 μg QEs/mg, respectively. The survival rate of B16-F10 murine melanoma cells treated with 750 μg ME and HE were 83.46% and 85.54%, respectively, thereby suggesting that mushroom extracts were slightly cytotoxic at the tested concentration. The in vitro tyrosinase inhibition by ME (83.15%) and HE (83.44%) was significantly lower than that of kojic acid (99.61%), the positive control, at 2.0 mg/mL. Although the inhibition of cellular melanin synthesis in B16-F10 melanoma cells by 2.0 mg/mL of ME (50.24%) and HE (51.24%) was lower than that of arbutin (64.84%), the inhibition by both ME and HE was higher than 50%. Collagenase inhibition by HE was comparable to 2.0 mg/mL epigallocatechin (EGCG), the positive control; however, elastase inhibition by ME and HE was lower than that of EGCG at the concentration tested. The results showed that the fruiting bodies of G. applanatum had good anti-tyrosinase, good anti-collagenase, and moderate anti-elastase activities, which might be useful for developing novel skin-whitening and anti-wrinkle agents.

This study was conducted to investigate a suitable substrate formulation for bag cultivation of Hypsizygus marmoreus. To determine the optimum media composition for H. marmoreus, chemical properties of various media and culture properties were investigated. The fastest primordia formation (9.0 days), the shortest fruiting body harvest period (18.0 days), and the highest yield (144.7 g/bag) were realized with the T6 formulation (55:15:20:5:5 mixing ratio of poplar sawdust, wheat bran, rice bran, dried soybean powder, and palm kernel, respectively). The chemical properties of the T6 formulation were pH, 6.0; total carbon, 19.0%; total nitrogen, 0.83%; C/N ratio, 22.8; P2O5, 0.61%; K2O, 0.46%; and MgO, 0.29%. This is the first attempt using plastic bags for cultivation and will help expand the production of H. marmoreus.

In this study, monokaryons of “Heukari” (Pleurotus ostreatus) and “Hosan” (Pleurotus pulmonarius) were separated to remove the cell wall, and a cross-species protoplast fusion was developed through chemical treatment with polyethylene glycol . The protoplast-fused PF160306 and PF160313 strains have a culture period of 10 and 2 days shorter than that of the “Heuktari” and “Hosan” cultivars, respectively. Furthermore, the growth of the strains was faster than that of the existing cultivars. The yield was 135.9 g per bottle, which was approximately 8% higher than that of the commercially available “Hosan” cultivar; however, it was not statistically significant. A growth survey was conducted after treatment at five temperatures (15, 18, 21, 23, and 25oC). The growth of the strains accelerated with the increase in temperature. However, at 21oC, the yellow color of pileus was the brightest. Band pattern, assessed using URP Primer 7, was similar to that of the “Hosan” cultivar. The DPPH radical scavenging capacity and polyphenol content were 62.5% and 43.5 mg/mL, respectively, for “Sunjung” and 65.7% and 49.9 mg/mL, respectively, for PF160313. Furthermore, the antihypertensive activities of the “Sunjung” cultivar and PF160313 were similarly high at 74% and 75%, respectively. In conclusion, cross-species hybridization via the protoplast fusion technique can be used for obtaining primary data for mushroom breeding to develop new varieties. In addition, the protoplast fusion technique might aid in expanding the market for yellow mushrooms.

In this study, the anti-inflammatory activity of an extract of the fruiting body of the Tuber himalayense (TH) truffle collected from oak growing areas in Korea was investigated. The extract was not cytotoxic at concentrations below 100 μg/mL in an experiment evaluating inflammation inhibitory effect in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. LPSinduced nitric oxide (NO) and prostaglandin E2 (PGE2) production was inhibited by the extract in a concentration-dependent manner. Western blot assay results indicated that the anti-inflammatory activity of TH extract was likely caused by the reduced production of NO and PGE2 via suppression of induced NO synthase and cyclooxygenase-2 gene expression. In addition, TH extract effectively inhibited the production of interleukin (IL)-1β and IL-6 by macrophages. Thus, TH extract effectively inhibits the overexpression of various inflammatory mediators and could be valuable in formulating anti-inflammatory foods and medicines that target these components.

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.

This study was conducted to improve the useful components and biological activity of Lentinula edodes fermented by lactic acid bacteria (LAB). Three LAB strains (Lactobacillus brevis KCCM 11904, L. plantarum KCCM 354469, and L. fermentum KCCM 12116) were inoculated and used for L. edodes hot water extract (10%, 20%, 30%) fermentation. LAB fermentation of L. edodes hot water extracts decreased pH and thus were more acidic than non-fermented L. edodes hot water extract. β-glucan and ergothioneine contents were increased by L. edodes in a concentration-dependent manner. The ergothioneine and β-glucan contents were highest in fermented with 30% L. edodes hot water extract fermented by L. plantarum and L. brevis (40.48 mg/ 100 g and 13.94%, respectively). The hepato-protective effect of fermented L. edodes hot water extracts by the three LAB were tested using Sprague-Dawley rat primary hepatocytes. In primary hepatocytes obtained following liver injury induced by acetaminophen, fermented L. edodes hot water extracts by the three LAB showed protective effects, as evident by reduction of the aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase liver markers. The collective results indicate that the fermented L. edodes hot water extracts obtained using LAB are potentially valuable in preventing or treating liver disease.

In this study, a low-salt Lentinula edodes soybean paste (LSLESP) with improved palatability and storability relative to traditional Korean soybean paste was developed by utilizing low quality log cultivation of L. edodes. We also conducted quality characteristic analyses of spread jam made from low-salt L. edodes soybean paste (SJLLESP). The lowest salinity content and the highest L (brightness) value was found in LSLESP. According to proximate compositions analysis, crude protein, crude fat, and ash content were higher in commercial soybean paste than in LSLESP. Glucose, fructose, and maltose were the only free sugars detected in commercial soybean paste, whereas arabinose and fucose were additionally detected in LSLESP. Only two types of organic acid, were detected in common in commercially available soybean paste and LSLESP. Four types of organic acid, were detected in SJLLESP due to its added ingredients. The major free amino acids in commercially available soybean paste and LSLESP are histidine, glutamic acid, and arginine. Total amino acid, content was higher in LSLESP (54.81 mg%) than in commercial soybean paste (49.26 mg%). Total free amino acid, content in SJLLESP was 43.01 mg%. Ergosterol and β-glucan contents were highest in SJLLESP. The elevated ergosterol and β-glucan content in low-salt LSLESP relative to commercial soybean paste was significant. In conclusion, LSLESP and SJLLESP contain useful components from L. edodes, and offer the advantage of low salinity. LSLESP and SJLLESP could thus contribute to the development of health foods using L. edodes.

For sterilization of microorganisms of the Listeria genus contaminating enoki mushroom, pilot mushroom grower equipped with air sterilization devices were developed. Sterilization experiments were performed using physical and chemical treatments. Internal temperature and humidity were controlled, maintaining 6.62oC±0.30 in the upper shelves, 6.46oC±0.24 in the middle shelves, and 6.48oC±0.25 in the lower shelves. Humidities were 79.97%±4.42, 79.43%±4.06, and 79.94±4.30%, respectively, with a temperature setting of 6.5oC, and a relative humidity of 75%. A suitable enoki mushroom cultivation stage for air sterilizer application was during the growth stage, with temperature in the 6.5~8.5oC range, and humidity of 70~80%. At these same internal conditions, the ozone concentration in the mushroom cultivator was found to be 160 ppb during ion-cluster generator operation. After physical sterilization, the Listeria innocua survival rate was 0.1 to 0.9% using ion cluster sterilization, and 9.3 to 10.6% using UV air sterilization. The Listeria innocua survival rates on different materials were 9.3~10.6% on the metal specimen, and 9.9~16.2% on the plastic wrapper. The survival rate was particularly high on the rough side of the plastic wrapper. Ion cluster air sterilization is a labor-saving and effective method for suppressing the occurrence of Listeria bacteria on mushroom growers walls and shelves. For the plastic wrapper, chemical sterilization is more effective than physical sterilization.

This study analyzed food component characteristics and antioxidant activities in five kinds of domestic commercial shiitake mushrooms (Lentinula edodes). Moisture content (79.17-82.90 g/100 g) showed little difference, but there was a significant difference in crude protein content. Total mineral content showed a significant difference, and potassium (K) content was the highest. Total and essential amino acid contents were higher in mushroom A than in the other samples. Nonetheless, the ratios of essential amino acids, aspartic acid, and glutamic acid to total amino acids were similar in all samples. β-Glucan content was in the range of 10.28-5.68 g/100 g, exhibiting a significant difference. The color intensity and overall texture of the mushrooms showed no remarkable difference. Total phenol and flavonoid contents were in the range of 19.92-30.77 mg/100 g and 6.95-10.39 mg/100 g, respectively; the ratio of flavonoids to total phenols ranged from 31.53% to 38.21%. DPPH and ABTS radical scavenging activities were 74.92-79.04% and 80.47-84.97%, respectively, and showed little difference. However, the reducing power varied between 195.23 μM and 317.85 μM, displaying a significant difference in all samples. Therefore, this study observed similar trends in the food component characteristics and antioxidant activities of domestic commercial shiitake mushrooms.

In this study, we evaluated the anti-inflammatory effect of extract from Cudrania tricuspidata twig sawdust fermented with Ganoderma lucidum mycelium. Fermented Cudrania tricuspidata twig sawdust extracted with 70% ethanol and elucidated the potential signaling pathway in lipopolysaccharide (LPS)-induced RAW264.7 cells. Fermented Cudrania tricuspidata twig sawdust inhibits LPS-stimulated nitric oxide (NO) production without affecting cell viability in a dose-dependent manner and production of LPS-induced pro-inflammatory cytokines such as interleukin (IL)-1β, tumor necrosis factor (TNF)-α and prostaglandin2 (PGE2). Fermented Cudrania tricuspidata twig sawdust also suppressed the expression of the pro-inflammatory mediators such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-stimulated RAW264.7 cells. Moreover, Fermented Cudrania tricuspidata twig sawdust significantly attenuated LPS-induced IkappaB (IκB) degradation and suppressed nuclear factor kappa B (NF-κB) nuclear translocation. These results suggest that fermented Cudrania tricuspidata twig sawdust may have great potential for the development of anti-inflammatory agent.

To extend the shelf life of king oyster mushrooms for export, we investigated the impacts of mushroom quality grade, fruiting body trimming, and packaging method (tray container sealed packaging vs string-tied OPP bag packaging). Quality is divided into two grades: 1st grade, which is mushrooms adapted by lowering the cultivation temperature to 9~11oC, and 2nd grade, mushrooms held at 13~15oC prior to harvest. Using selected 1st and 2nd grade mushrooms, 3 treatments were carried out to assess effects of trimming and packaging method. Test groups included 1) trimming plus string-tied OPP bag packaging (Cut & OPP), 2) no trimming plus string-tied OPP bag packaging (Uncut & OPP), and 3) trimming plus tray container sealing packaging (Cut & Tray). Gas composition inside the packaging, changes in quality factors, and sensory evaluation for fresh quality were performed over 42 days of 0oC storage. Overall freshness was best maintained in the following order: Cut & Tray > Cut & OPP > Uncut & OPP for both 1st and 2nd grade mushrooms. The shelf-life of 1st grade mushrooms was about 30 days for Cut & Tray, 28 days for Cut & OPP, and 21 days for Uncut & OPP. The shelf-life of 2nd grade mushrooms was about 22 days for Cut & Tray, 17 ays for Cut & OPP, and 14 days for Uncut & OPP. Factors affecting fresh mushroom quality included browning of cap and stalk, and mushroom decay index. Browning of the lower part of the stalk, with related color change as noted in a* and b* values were the main factors indicating quality deterioration of king oyster mushrooms.

The main characteristics of a new cultivar ‘Jinhyang’, a cross of a collection of monokaryotic strains of the brown button mushroom, were examined. ‘Jinhyang’ was not significantly different from the control cultivar ‘Dahyang’ in mycelial culture and cultivation period. The cap of ‘Jinhyang’ was thicker and darker in color than that of ‘Dahyang’. The hardness and individual weight of the fruiting body of ‘Jinhyang’ were slightly higher than those of ‘Dahyang’; however, the differences were not significant. The yield of ‘Jinhyang’ was 14.1 kg/m2, which was 8% higher than that of ‘Dahyang’. Therefore, it is expected that it will be possible to supply this cultivar growers in the future.

The competitiveness of the mushroom industry can be increased by diversifying the domestic Lentinula edodes cultivar. Therefore, ‘Chungheung 1ho’ was cultivated by hybrid breeding method using strain ‘E140025,’ which was collected by the Chungheung Mushroom Farming Association. Regarding the morphological characteristics of the fruit, the cap of ‘Chungheung 1ho’ was smaller than that of the control cultivar, whereas, its stem was longer and thicker than that of the control cultivar. In addition, the weight of the individual fruits of the new cultivar was heavier than that of the control cultivar. The period for primordia formation was 24 days for the new cultivar, which was 16–20 days later than that of the control cultivar. Furthermore, it was found that the patterns of the PCR amplification band using six URP primers were different for ‘Chungheung 1ho’ than those of the mating strains.

Currently, button mushroom, Agaricus bisporus is one of the most consumed mushroom in the world. However, despite of its importance in food market, molecular genetic modification method for breeding of A. bisporus is not well established. In this study, we optimized yield of A. bisporus protoplast with Lysing enzyme, Chimax-N and cellulase. With this composition, 1.0 × 108/mL of protoplasts were obtained reliably. PEG-mediated transformation with spermidine showed almost 100-fold higher yield than non-spermidine method.