• Korean Journal of Microbiology
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• v.50 no.1
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• pp.15-21
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• 2014

The promoting effect of Pseudomonas sp. P7014 on the mycelia growth of Pleurotus eryngii was investigated. An ethyl acetate fraction (F5) from the culture supernatant of the bacteria was confirmed to contain the growth promoting compound (GPC). The GPC was identified to be indole acetic acid (IAA) by TLC, HPLC, MS/MS, and NMR analyses. P. eryngii mycelia grew rapidly both on PDA and in PDB after the treatment of GPC. The promoting concentration of GPC was as low as 1.0 nM. Tryptophan, the aminated form of IAA, was confirmed to be the precursor of IAA. These results suggested that bacterial secreted compound was IAA and plays an important role in promoting growth of mushroom mycelia.

• Journal of Mushroom
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• v.11 no.4
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• pp.297-302
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• 2013

Pleurotus eryngii is one of the main export items in Korean mushroom industry. Whole mushrooms were packed with 30 um polypropylene anti-fog film without trimming. The range of package weight and oxygen permeability of film were 400 g and 2000 $c/m^2$, 24 h,atm, respectively. The anti-browning treatments were sprayed by 0.5%(w/w) solution of Sporix Sporix(Sodium polyphosphate and $ClO_2$ gas The weight loss ratio was increased with increasing shelf period and temperature. There were no big differences in weight loss ratio according to browning inhibitors. In case of $ClO_2$ treatment, the hardness and lightness of stem was showed higher than other treatment for shelf period. As results of freshness, the optimum browning inhibitor of P. eryngii was $ClO_2$ treatment and the shelf life was extended 36days at $10{\sim}15^{\circ}C$.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.6
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• pp.932-938
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• 2010

This study was performed to determine the proximate analysis of Pleurouts eryngii and quality characterisitcs of pork cutlet sauce with added king oyster mushroom (Pleurotus eryngii). Pork cutlet sauce was prepared with different levels of king oyster mushroom powder (0, 1, 3, 5, and 7%) and stored for 21days at $25^{\circ}C$. Antioxidant activity was significantly increased by addition of king oyster mushroom powder (p<0.001). L, a and b value ignificantly increased with the increased of king oyster mushroom powder concentration. As king oyster mushroom powder concentration increased, pH value was increased and titratable acidity (%) value was decreased. pH value and titratable acidity (%) value were stable during storage period. Viscosity value and $Brix^{\circ}$ were significantly increased by addition of king oyster mushroom powder (p<0.001). The overall acceptability, sweetness and taste of the pork cutlet sauces with added 5% king oyster mushroom powder attained high scores.

• Mycobiology
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• v.37 no.4
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• pp.258-266
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• 2009

Pleurotus eryngii, known as king oyster mushroom has been widely used for nutritional and medicinal purposes. This study was initiated to screen the suitable conditions for mycelial growth and to determine the phylogenetic relationship of the selected strains. Optimal mycelial growth was observed at $30{^{\circ}C}$ and minimum mycelial growth observed at $10{^{\circ}C}$. This mushroom tolerates a broad pH range for mycelial growth, with most favorable growth observed at pH 6. Results also indicated that glucose peptone, yeast malt extract and mushroom complete media were favorable growth media, while Hennerberg and Hoppkins media were unfavorable. Dextrin was the best and xylose the least effective carbon sources. Results revealed that inorganic nitrogen sources were less effective than organic sources for the mycelial growth of P. eryngii. Investigation of genetic diversity is necessary to identify the strains. The ITS region of rDNA were amplified using PCR. The size of the ITS1 and ITS2 regions of rDNA from the different strains varied from 214 to 222 bp and 145 to 236 bp, respectively. The sequence of ITS2 was more variable than that of ITS1, and the 5.8S sequences were identical. A phylogenetic tree based on the ITS region sequences indicated that selected strains could be classified into six clusters. Fourteen IUM and ATCC- 90212 strains were also analyzed by RAPD with 20 arbitrary primers. Fourteen of these primers were efficiently amplified the genomic DNA. The number of amplified bands varied with the primers and strains, with polymorphic fragments in the range from 0.2 to 2.3 kb.

• Proceedings of the Microbiological Society of Korea Conference
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• 2009.05a
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• pp.79-80
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• 2009

• Korean Journal of Food Science and Technology
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• v.38 no.6
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• pp.799-804
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• 2006

Antioxidative and antimicrobial activities were measured for the Pleurotus eryngii (P. eryngii) solvent extracts in order to discover new functional activities. In P. eryngii, the powder moisture was 9.0%, and the carbohydrate, crude protein, crude ash and crude fat contents were 63.06, 20.70, 5.20 and 2.0%, respectively. Among the detected minerals, potassium (K) had the highest levels and manganese (Mn) the lowest. The amount of polyphenol in EtEx (Ethanol Extract) was 387 mg% for the whole body, 158 mg% for the stipe, and 593 mg% for the pileus. Higher levels of polyphenol in the entire body were found in the BuEx (Butanol Extract) (594 mg%) and WaEx (Water extract) (404 mg%) of the P. eryngii powder. BuEx had the highest level in the pileus, and EtEx and BuEx were higher than the other extracts in the stipe. The electron donating ability (EDA) of EtEx of the P. eryngii powder was the highest, at 91.12%, for the whole body, while it was the lowest, at 62.90%, in the stipe. In addition, the EDA of WaEx was 90.39% for the whole body. These EDA values were similar to those for tocopherol (93.93%) and BHT (96.72%), supporting the potential of these extracts to act as antioxidants. A number of the extracts were certified to have antimicrobial activities for small number of microorganisms, especially for gram-negative microorganisms. In other words, BuEx and EAEx in the pileus and WaEx in the stipe were found to inhibit the growth of Pseudomonas aeruginosa (gram negative). Additionally, EtEx and WaEx in all parts were shown to act as antimicrobial agents for Escherichia coli of gram negative.

• The Korean Journal of Mycology
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• v.42 no.2
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• pp.159-164
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• 2014

For development of a method for differentiation of Pleurotus eryngii cultivars, simple sequence repeats (SSR) from whole genomic DNA sequence analysis was used for genotyping and two multiplex-SSR primer sets were developed. These SSR primer sets were employed to distinguish 12 cultivars and strains. Five polymorphic markers were selected based on the genotyping results. PCR using each primer produced one to four distinct bands ranging in size from 200 to 300 bp. Polymorphism information content (PIC) values of the five markers were in the range of 0.6627 to 0.6848 with an average of 0.6775. Unweighted pairgroup method with arithmetic mean clustering analysis based on genetic distances using five SSR markers classified 12 cultivars into two clusters. Cluster I and II were comprised of four and eight cultivars, respectively. Two multiplex sets, Multi-1 (SSR312 and SSR366) and Multi-2 (SSR178 and SSR277) completely discriminated 12 cultivars and strains with 21 alleles and a PIC value of 0.9090. These results might be useful in providing an efficient method for the identification of P. eryngii cultivars with separate PCR reactions.

• Food Science and Preservation
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• v.24 no.3
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• pp.381-386
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• 2017

Ergocalciferol is known as having vitamin D activity. In this study, the effects of UV irradiation on the increase of egocalciferol content were investigated in 7 kinds of mushrooms, i.e, lily mushroom (Flammulina velutipes), oyster mushroom (Pleurotus ostreatus), young oyster mushroom (Pleurotus ostreatus), king oyster mushroom (Pleurotus eryngii), button mushroom (Agaricus bisporus), shiitake (Lentinula edodes), and wood ear mushroom (Auricularia auricula-judae). Mushrooms which were not exposed to UV light contained negligible amount of ergocalciferol in all kinds of tested mushrooms, but UV irradiation increased their content of ergocalciferol. Of UV A, B and C, UV B light was the most effective to increase ergocalciferol contents. In mushrooms, the increase in ergocalciferol content occurred only in the peel within 1 mm depth from the surface, which was directly exposed to the UV light. Therefore, when fresh whole mushrooms were irradiated with UV light, lily mushroom, the mushroom with a larger surface area compared to volume, such as lily mushroom, was more favorable in producing ergocalciferol. On the other hand when the mushrooms were freeze-dried and cut, the mushrooms with a higher ergosterol, such as king oyster mushroom, shiitake or button mushroom, were more favorable in generating ergocalciferol.

• Mycobiology
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• v.36 no.2
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• pp.106-109
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• 2008

The anti-tumor effects of exo- (EX) and endo-biopolymers (EN) produced from submerged mycelial cultures of Ganoderma applanatum (GA), Collybia confluens (CC), and Pleurotus eryngii (PE) were studied using Sarcoma 180 bearing mice. Solid tumor growth was inhibited most effectively when 40 mg/kg body weight (BW) of GA-EX or PE-EN was administered to the intraperitoneal (i.p.) cavity of BALB/c mice. The spleen and liver indexes were increased in mice following i.p. administration of GA-EX and PE-EN fractions. GA-EX and PE-EN reduced the tumor formation by 30.7% and 29.4%, respectively. GA-EX and PE-EN increased the natural killer (NK) cell activity of splenocytes by 41.3% and 28.9%, respectively.

• The Korean Journal of Mycology
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• v.44 no.1
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• pp.31-35
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• 2016

This study was conducted to test whether post-harvest medium of king oyster mushroom can be recycled for its bottle cultivation. Physical properties of the post-harvest medium and the resulting yield of fruit bodies revealed no significant difference compared with control. Recycling post-harvest medium can be replaced to 15% of the basal medium, thus decreasing the cost of raw materials up to 15%.