Earticle

Hot water soluble extract was prepared from Hericium erinaceus and its neuritogenic activity on PC12h cells was analyzed, which is a clone originating from a rat pheochromocytomon. The moisture content of freeze dried hot water extract was 12.08%. The extract was mainly composed of carbohydrate (51.24%) followed by crude protein (24.04%), crude fat (0.26%), dietary fiber (5.09), and ash (12.18%). Fatty acids, glucan and inorganic constituents were found as minor components. The neuritogenic activity of hot water extract was evaluated under microscopic observation of neurite outgrowth in PC12h cells and by measuring the neurite length of induvidual cell. The extract exhibited strong effect of neurite outgrowth in a dose-dependent manner from 0.01 mg/mL to 1 mg/mL, in which longer neurite outgrowth was observed as the treatment dose increased.

The effects of environmental and nutritional requirement such as temperature, pH, different media, carbon, nitrogen, and carbon-to-nitrogen ratio on the mycelial growth of Cordyceps militaris strain ‘Yedang 3’ were studied. The optimum temperature and pH for the growth of mycelium were 20-25oC and pH 6-7, respectively. Out of ten media tested, mushroom complete media (MCM) was the best medium for fast mycelial growth, and Sabouraud’s dextrose agar yeast extract (SDAY), malt extract yeast extract agar (YMA) also were favored. The color and shape of colonies varied in different media. The best carbon sources for mycelial growth were fructose, mannitol, and sucrose, whereas the best nitrogen sources were tryptone and peptone. However, mycelia grew slowly in inorganic nitrogen compounds such as NH4Cl, (NH4)2SO4, NH4NO3, and NaNO3. The optimum C:N ratio observed on the culture media was 30-40 range. These results provided basic information on cultural characteristics of vegetative growth and might be useful for spawn production in Cordyceps militaris.

The effects of fixed and variable relative humidity on fruiting body formation and characters of Pleurotus eryngii were investigated with normal and thinning treatment plots. In fixed relative humidity, as humidity was lower, period of harvest was longer as well as days for pinheading in the both of normal and thinning plots. In the normal plot, qualities of mushroom were 5.5, 5.8, and 6.3 and yield was 98.6 g per bottle for 90% relative humidity, it was best. In the thinning plot, qualities of mushroom were 7.7, 8.4, and 8.5 and yields were 102.1, 105.8, and 116.9 g at 70, 80, and 90% respectively. In variable relative humidity with a thinning plot, the yield of P. eryngii on condition I(>90% for 1 day → 85% until thinning(for about 11 days) → 80%) and III(>90% until pin-heading(about for a week) → 85% until thinning(about for 5 days) → 80%) were 85.5 and 87.8 g per bottle, and qualities were 7.8 and 8.0 respectively. For long shelf life and a cultural control of bacterial soft rot disease, the condition I will be more largely adopted by mushroom farmers.

This study was carried out to investigate storage stability of harvested mushroom in developed varieties of button mushroom through identification of quality change during 35 days. The mushroom harvested up to 2nd flush mushroom was stored on different storage temperature(4, 7, 10oC) and weight, length, thickness, color of pileus and stipe in fruit body was tested every 7 days. The morphological trait and color of stipe in fruit body were influenced by harvesting period and storage temperature. On the morphological traits of fruit body, mushroom harvested at 2nd flush showed smaller difference than those at 1st flush and mushroom stored at 4oC indicated more difference than ones at the other temperature. Mostly color of pileus in brown button mushroom had lower E (color difference) than white mushroom during storage period. The color of pileus of fruit body in white mushroom had low E at 4oC whereas that of brown mushroom was low at 10oC. The safe period of storage based on the L value is 7 days under a specified environmental condition. ‘Seolgang’ was stored for 14 days as good quality of mushroom, ‘Saedo’ had best quality after harvesting and ‘Seojeong’ was most stable during storage change in white mushroom varieties.

Studies were made to optimize the media composition and cultural condition for mycelial growth of ear mushroom(Auricularia auricula). Sawdust spawn of media composition for optimal growth were found to be quercus sawdust combination of 20% rice bran and poplar sawdust combination of 10% wheat bran were the best of the optimal combination. The optimal condition of the most suitable inoculation amount showed that quercus spawn and poplar spawn were 15g, 25g, respectively.

The oyster mushroom is a wide cultivar among cultivated edible mushrooms in Korea. But, due to the excess of domestic production, the price has been falling. This study has been conducted to develope new variety oyster mushroom(Pleurotus ostreatus) which have a long term storage to export in foreign market as well as domestic. ‘Gonji-7ho’, a new variety of oyster mushroom, for the bottle culture, was bred by mating with monokaryons isolated from ‘Nongmin-59ho’ and ‘MT07156’. In the characteristics of fruit body, pilei were round type and gray and stipes were white color and soft. The fruit body growth was vital and uniform. When fruit-body was stored at 4 degrees after packing with plastic vinyl, storage period was extended 7 days longer than 28 day of chunchu- 2ho. The yield was 166 g per a bottle(￠65, 900 ml)

To develop a new variety of oyster mushroom(Pleurotus ostreatus), parental strains was selected by the method of Mon-Mon crossing between monokaryotic strains derived from ASI 2596(Suhan No.3) and ASI 2782(Black pileus mutant). The SB-73(ASI 2596-11 x 2782-8) was shown the best cultural characteristics, selected to be a new variety and named as ‘Dagul’. The ‘Dagul’ was formed incompatibility line distinctly in the confrontation growth of parental strains Suhan No.3 and ASI 2782. The optimum temperature for mycelial growth, fruiting body development and pH arrange were 25~30oC, 14~17oC and pH5~8, respectively. Fruiting body production per bottle was about 68.024.1 g which is almost 115% quantity compared to that of other variety Suhan No.3. And also the stipe is long and individual generation is multiple. Analysis of the genetic characteristics of the new variety ‘Dagul’ showed different DNA bands as that of the control strains, Suhan No.3 and ASI 2782, when RAPD(Random Amplified Polymorphic DNA) primers URP7 and Rcb1 were used. This new variety 'Dagul' of oyster mushroom is characterized by multiple of individual generation and the stipe is long. We therefore expect that this new strain will increase of the income by cultivation of field.

We made the first Korean white commercial strain ‘Baek-a’ developed by crossing between monokaryons derived from brown strains. This variety can be estimated as the Korea’s indigenous one different from the origin of Japanese white ones. The optimum temperature of mycelial growth was 25oC but it needed to adjust to 18~20oC when incubated at the bottle cultivation. The optimum temperatures of fruiting body initiation and development were 12~13oC and 67oC, respectively. Fruiting body of ‘Baek-a’ was pure white even developed from crossing with brown strains. ‘Baek-a’ was a good variety with high quality and high productivity characterized as quite even budding habit, long stipes and hemi-spherical pilei. The days for the fruiting was 7 days and the productivity was 11134 g per 850 ml. This variety needed high concentration of carbon dioxide and it had to be adjusted up to 4,000 ppm for the good quality.

This study was carried out to compare the medicinal effects of various fruiting body of Ganoderma species and Cordyceps militaris, Phelinus linteus extracts. B-glucan and polyphenol are useful ingredient in mushrooms and they were known to have antioxidant activity. We analyzed B-glucan and polyphenol contents of fruiting body of Ganoderma spp., Cordyceps militaris, and Phellinus linteus. Most Ganoderma spp. exhibited B-glucan contents of 15 to 20%. Cordyceps militalis showed the highest B-glucan level of 25%. Interestingly, eight strains of Ganoderma spp. was analyzed to have higher contents of B-glucan than Phelinus linteus. Polyphenol contents was measured after extraction with different solvents. (D.W., 70% EtOH, 80% MeOH) The level of polyphenol in ASI 7020 strain was at maximum in the water extraction and ASI 7086 showed the highest level in the 70% EtOH extraction. The amounts of polyphenol in strain ASI 7113 was at maximum in the 80% MeOH extraction.

Genomic DNAs of psychrophilic strains of Pleurotus eryngii were analyzed by randomly amplified polymorphic DNA (RAPD) using OP-A, OP-B, OP-L, OP-P, OP-R and OP-S3 primers to develop the strain-specific DNA marker. A unique DNA fragment with the size of 480 bp was yielded by OP-S3 primer from the psychrophilic strain. A sequence characterized amplified region (SCAR) marker, designated as OP-S3-1, was designed on the basis of the determined sequence. The PCR analysis with the OP-S3-1 primer showed that this SCAR marker can clearly distinguish the psychrophilic strains from the control strains.

The project spanned from 2009 to 2012, including 19 kinds of oyster varieties, 34 were advertised in the national 387 places. As a result, the proliferation of demonstration farms spread around the 30% (2009) share of domestic varieties 45% (2012) raised to the level. Early varieties of these domestic supply system more efficient, the central and local governments in order to promote dissemination of the technology of that business was expanded to promote.