Pheromone (PHB)-receptor (RCB) interaction in the mating pheromone response pathway of Lentinula edodes was investigated using synthetic PHBs. Functionality of the C-terminally carboxymethylated synthetic PHBs was demonstrated by concentration-dependent induction of a mating-related gene (znf2) expression and by pseudoclamp formation in a monokaryotic strain S1-11 of L. edodes. Treatment with synthetic PHBs activated the expression of homeodomain genes (HDs) residing in the A mating type locus, and of A-regulated genes, including znf2, clp1, and priA, as well as genes in the B mating type locus, including pheromone (phb) and receptor (rcb) genes. The synthetic PHBs failed to discriminate self from non-self RCBs. PHBs of the B4 mating type (B4 PHBs) were able to activate the mating pheromone response pathway in both monokaryotic S1-11 and S1-13 strains, whose B mating types were B4 (self) and B12 (non-self), respectively. The same was true for B12 PHBs in the B4 (non-self) and B12 (self) mating types. The synthetic PHBs also promoted the mating of two monokaryotic strains carrying B4-common incompatible mating types (A5B4 × A1B4). However, the dikaryon generated by this process exhibited abnormally high content of hyphal branching and frequent clamp connections and, more importantly, was found to be genetically unstable due to overexpression of mating-related genes such as clp1. Although synthetic PHBs were unable to discriminate self from non-self RCBs, they showed a higher affinity for non-self RCBs, through which the mating pheromone response pathway in non-self cells may be preferentially activated.
Lentinula* ; Pheromones* ; Shiitake Mushrooms*

The effects of monokaryotic strains on fruiting body formation of Lentinula edodes were examined through mating and cultivation of the mated dikaryotic mycelia in sawdust medium. To accomplish this, monokaryotic strains of L. edodes were isolated from basidiospores of the commercial dikaryotic strains, Chamaram (Cham) and Sanjo701 (SJ701). A total of 703 matings (538 self-matings and 165 outcrosses) were performed, which generated 133 self-mates and 84 outcross mates. The mating rate was 25% and 50% for self-mating and outcross, respectively. The bipolarity of the outcross indicated the multi-allelic nature of the mating type genes. The mating was only dependent on the A mating type locus, while the B locus showed no effect, implying that the B locus is multi-allelic. Next, 145 selected dikaryotic mates were cultivated in sawdust medium. The self-mated dikaryotic progenies showed 51.3% and 69.5% fruiting rates for Cham and SJ701, respectively, while the fruiting rate of the outcross mates was 63.2%. The dikaryotic mates generated by mating with one of the monokaryotic strains, including A20, B2, E1, and E3, showed good fruiting performance and tended to yield high fruiting body production, while many of the monokaryotic strains failed to form fruiting bodies. Overall, these findings suggest that certain monokaryotic strains have traits enabling better mating and fruiting.
Fruit* ; Shiitake Mushrooms*

Severe bark decay disease was observed on oak logs at a shiitake cultivation farm in Geochang-gun, Gyeongnam province. The symptoms observed were fruiting bodies that had developed on the top and side surface of oak logs. As a result, the bark came off easily exposing the sapwood. Slime mold specimens collected from oak logs showed developing fruiting bodies comprising of stalks, hypothallus, capillitium, and columella, and the causal agent of bark decay disease was identified as Stemonitis splendens on the basis of morphological characteristics. To our knowledge, this is the first report of Stemonitis splendens causing bark decay of oak logs used for shiitake mushroom cultivation in Korea.
Fruit ; Fungi ; Korea ; Shiitake Mushrooms

Shiitake (Lentinus edodes) is nowadays the second most commonly produced edible mushroom in the world. Two patients complained of severe itching and showed widespread disseminated very small erythematous papule and characteristic linear grouped erythematous papules after scratching (Kobner phenomenon). Here we report two cases of mushroom intolerance which developed after ingestion of boiled or cooked shiitake mushrooms.
Agaricales* ; Eating ; Humans ; Pruritus ; Shiitake Mushrooms

The objectives of this study were to evaluate applicability of food waste compost (FWC) as a substrate for cultivation of Ganoderma lucidum, Lentinula edodes, and Pholiota adipose, and to determine contents of Ca, Mg, Na, and K in fruiting bodies (FB). FB yield per substrate in FWC-free controls was 53 +/- 4 g/kg for G. lucidum, 270 +/- 90 g/kg for L. edodes, and 1,430 +/- 355 g/kg for P. adipose. Substrates supplemented with FWC showed the highest FB production at FWC content of 10% for G. lucidum (64 +/- 6 g/kg), and 13% for L. edodes (665 +/- 110 g/kg) and P. adipose (2,345 +/- 395 g/kg), which were 1.2~2.5 times higher than the values for the controls. P. adipose contained higher amounts of mineral elements than the other species. Ca, Mg, Na, and K content in FB did not show a significant relation to FWC content.
Fruit* ; Ganoderma* ; Lentinula* ; Pholiota* ; Reishi* ; Shiitake Mushrooms* ; Soil*

Twenty isolates of Bacillus species obtained from livestock manure composts and cotton-waste composts were tested for their antagonistic effects in vitro against three green mold pathogens of mushrooms (Trichoderma harzianum, T. koningii, and T. viridescens). However, there exists a possibility Bacillus species may have antagonistic effects against mushrooms themselves, and thus the same 20 isolates were tested in vitro against three species of mushrooms (Flammulina velutipes, Lentinus edodes, and Pleurotus ostreatus). Of the 20 Bacillus species isolates tested, two inhibited mycelial growth of T. harzianum, seven that of T. koningii, and eight that of T. viridescens. Importantly, the bacterial isolates M27 and RM29 strongly inhibited mycelial growth of all the Trichoderma spp. isolates tested. The isolate M27 was subsequently identified as the most effective in inhibiting mycelial growth of all the Trichoderma species. Interesting results of the effect Bacillus isolates had upon the mushroom species followed. It was found that most Bacillus isolates except 5T33 at least somewhat inhibited mycelial growth of the three mushroom species or some of the mushrooms. Furhermore, the antagonistic effects of the bacterial isolates against the three species of mushrooms varied depending on the mushroom species, suggesting a role for mushroom type in the mechanism of inhibition. The bacterial isolates M27 and RM29 were identified as having the most antagonistic activity, inhibiting mycelial growth of all the Trichoderma spp. as well as mycelial growth of the three species of mushrooms. These results suggest that the bacterial isolates and their antagonistic effects on green mold pathogens should be further studied for their practical use for biological control of green mold in the growing room of the mushrooms.
Agaricales ; Bacillus ; Fungi ; Livestock ; Manure ; Pleurotus ; Shiitake Mushrooms ; Soil ; Trichoderma

The effects of aeration through lid filters on the hyphal growth of Lentinula edodes (oak mushroom) in sawdust cultivation bags were investigated. The aeration treatment levels were traditional 27 mm hole cotton plugs, cotton balls and combinations of seven hole sizes x two hole positions (up and under) in the lids covering plastic bags containing 1.4 kg sawdust medium at 63% moisture that had been autoclaved for one hour and inoculated with sawdust spawn of L. edodes strain 921. Aeration treatment effects were measured based on the CO2 concentration at the 15th wk, as well as the hyphal growth rate and degree of weight loss of bags every 14 days for 15 wk. In bags with traditional cotton plugs, the CO2 concentration was 3.8 +/- 1.3%, daily mean hyphal growth was 2.3 +/- 0.6 mm and daily mean weight loss was 0.84 +/- 0.26 g. In the bags with 15 mm diameter holes, the CO2 concentration was 6.0 +/- 1.6%, daily hyphal growth was 2.8 +/- 0.2 mm and daily weight loss was 0.86 +/- 0.4 g. The bags with 15 mm holes had a higher CO2 concentration and lower water loss than bags with other hole sizes, but the hyphal growth was not significantly different from that of other bags. The weight loss of bags increased proportionally relative to the lid hole sizes. Taken together, these results indicate that traditional cotton plugs are economically efficient, but 15 mm hole lids are the most efficient at maintaining hyphal growth and controlling water loss while allowing CO2 emissions.
Lentinula ; Plastics ; Shiitake Mushrooms ; Sprains and Strains ; Weight Loss

Shiitake mushrooms (Lentinula edodes) containing beta-glucans may be beneficial for human health; they have been used in the treatment of cancer, hypertension, and high cholesterol levels. The objective of this study was to determine the beta-glucan content in different sections of the fruiting bodies and mycelia of ten shiitake mushroom cultivars. The measured beta-glucan content ranged from 20.06 +/- 1.76% to 44.21 +/- 0.13% in the pileus sections, and from 29.74 +/- 1.40% to 56.47 +/- 4.72% in the stipe sections. The results of this study indicate that the variance in beta-glucan content dependent on the shiitake cultivar, and that the beta-glucan content is higher in the stipe than in the pileus.
beta-Glucans ; Cholesterol ; Fruit* ; Humans ; Hypertension ; Shiitake Mushrooms*

To obtain basic information on the biochemical property of basidiospores of shiitake mushroom (Lentinula edodes), the ability of producing extracellular enzyme was assessed using a chromogenic plate-based assay. For the aim, amylase, avicelase, beta-glucosidase, CM-cellulase, pectinase, proteinase, and xylanase were tested against monokaryotic strains generated from forty basidiospores of two different parental dikaryotic strains of shiitake mushroom, Sanjo-101Ho and Sanjo-108Ho. These two parental strains showed different degree of extracellular enzyme activity. No identical patterns of the degree of enzyme activity were observed between monokaryotic strains and parental strains of the two shiitake cultivars. The degree of extracellular enzyme activity also varied among monokaryotic strains of the two shiitake cultivars. Our results showed that dikaryotic parental strains of shiitake mushroom produce monokaryotic basidiospores having very diverse biochemical properties.
Amylases ; beta-Glucosidase ; Cellulases ; Humans ; Parents ; Polygalacturonase ; Shiitake Mushrooms

Shiitake (Lentinus edodes) is a kind of mushroom which is cooked and eaten as a food in Chinese, Japanese and Korean meals. It is nowadays the second most commonly produced edible mushroom in the world. In 1985, a case characterized by itchy skin eruptions after the ingestion of raw shiitake mushrooms was reported and was termed as toxicodermia. Here we report five cases of shiitake dermatitis which developed after ingestion of raw or cooked shiitake mushrooms. All patients complained of severe itching and showed linear grouped erythematous papules after scratching(Kobner phenomenon). To our knowledge, this is the first report of shiitake dermatitis in the Korean literature.
Agaricales ; Asian Continental Ancestry Group ; Dermatitis* ; Eating ; Humans ; Meals ; Pruritus ; Shiitake Mushrooms ; Skin