• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.64-69
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• 1991

- The effects of sodium acetate on the production of $\gamma$-linolenic acid (GLA) and the secretion of the mycelial lipid into the culture medium with noninnic surfactants were studied with Mucor sp. KCTC 8405P. In the addition of 2.0%) sodium acetate to the basal medium, dry cell weight and total lipid content were increased from 7.8 g/l and 2.46 g/l to 16.0 g/1 and 4.77 g/l, but GLA content was decreased from 18.6% to 13.85%. The growth of Mucor sp. KCTC 8405P was greatly dependent on both the initial pH and the concentration of sodium acetate of culture medium, which was considered as the results of the formation of acetic acid because the fungal growth was completely inhibited at the concentration of acetic acid higher than 22 mM. With the decrease of the oxygen supply, the cell growth, total lipid, and GLA content were sharply decreased in the presence of 2.0% sodium acetate. For the secretion of mycelial lipid into the culture medium, the effects of the various nonionic surfactants were examined. In the addition of 0.5% Tween 80 or Span 80 to the basal medium, 194 mg/l or 263 mg/l of GLA was obtained in the culture medium.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.507-516
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• 2014

The present study was conducted to determine the effect of electron beam irradiation on control of Botrytis cinerea and postharvest quality of cut roses. Electron beam doses of 0.1, 0.2, 0.4, 0.6, 0.8, 1, 2, 10, and 20 kGy were applied with a 10-MeV linear electron beam accelerator (EB Tech, Korea). Electron beams inhibited spore germination and mycelial growth of B. cinerea with increasing irradiation doses. Conidia of B. cinerea were more tolerant to irradiation than were mycelia: the effective irradiation doses for 50% inhibition ($ED_{50}$) of spore germination and mycelial growth were 2.02 kGy and 0.89 kGy, respectively. In addition, electron beam irradiation was more effective in reducing mycelial growth of B. cinerea at $10^{\circ}C$ than at $20^{\circ}C$. Analysis of in vivo antifungal activity revealed that elevated irradiation doses exhibited increased control efficacy for tomato gray mold. Flower longevity and fresh weight of cut roses decreased when the irradiation dose was increased. In addition, flower bud opening tended to be inhibited in a dose-dependent manner. Although 'Decoration', 'Il se Bronze', 'Queen Bee', and 'Revue' roses tolerated and maintained overall postharvest quality up to 0.4 kGy, 'Vivian' did not, demonstrating that the irradiation sensitivity of cut roses varies according to cultivar.

• Journal of Mushroom
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• v.3 no.1
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• pp.31-34
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• 2005

This experiment was carried out to examine on the physiological and cultural characteristics of commercial strain Kunneutari #3 of Pleurotus eryngii. The optimal medium suitable for mycelial growth was YM, and followed by MCM and PDA. Also this strain more faster mycelial growth as 6.1 cm/7days compared with commercial strain P. eryngii #1. The optimal mycelial growth temperature was $25{\sim}30^{\circ}C$. The fruitbody yield was increased 54% with $117{\pm}16g/850m{\ell}$ and the fruitbody shape and qualities of this strain was good. And individual weight was $41{\pm}27g$. Spawn run of P. eryngii #3 in bottle cultivation took 30 days and also it took 21 days from scratching of inoculum to harvest that was shorter 3 days than P. eryngii #1, respectively. Therefore, it is expected that cultivation for P. eryngii #3 strain will improve farmer's income by enhancing efficiency of facilities and shorten 6 days on cultivation period, in addition, getting more growing cycle of P. eryngii.

• The Korean Journal of Mycology
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• v.34 no.1
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• pp.1-6
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• 2006

In order to select a suitable bioreactor type for the submerged cultivation of Ganoderma applanatum, both growth characteristics and polysaccharides production were compared among four different types of bioreactor. These include an external-loop type air-lift bioreactor (ETAB), a balloon type air bubble bioreactor (BTBB), a column type air bubble bioreactor (CTBB) and a stirrer type bioreactor (STB). The mycelial biomass produced from the reactors were in decreasing order: ETAB ($7\;g/{\ell}$) > BTBB ($6.2\;g/{\ell}$) > STB ($6\;g/{\ell}$) > CTBB ($5\;g/{\ell}$). Maximal soluble exopolysaccharides ($1\;g/{\ell}$) and endopolysaccharides (2.7%) were also obtained from ETAB. Thus, the ETAB was most suitable for submerged culture of G applanatum mycelium. Based on the results, ETAB was chosen for further detailed study. The most effective aeration rate for the mycelial growth in ETAB ranged from 0.05 to 0.1 vvm. For the maximal production, the mycelium at the initial growth stage needed low aeration rate to reduce cell damages by fluid flow. However, as the mycelia grew, the culture became viscous and thus needed higher aeration. The molecular weight of exopolysaccharides obtained from the culture grown in ETAB was higher than that from the culture grown in other bioreactors.

• The Korean Journal of Mycology
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• v.25 no.4 s.83
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• pp.257-267
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• 1997

Fruit bodies similar to the Phellinus sp. residing on the mulberry were collected at Yang-yang in Kang-won-do province and one strain of Phellinus sp. was isolated from the fruit bodies. For mass production of the isolated mycelia in a submerged culture, the culture conditions, medium composition, and the effect of various culture systems on the mycelial growth, were investigated. The morphological characteristics of the fruit body were as follows: covered with blackish to black and rough, lower surface with yellowish-brown to dull-brown and smooth, 5-7 cm thick and hard woody. Also, the pure cultured mycelia showed yellowish-brown color, capability of purplish-brown pigment production on the PDA plate media, no-formation of clamp-connection, much binding branch, and enzyme activities such as laccase, tyrosinase and peroxidase. Therefore, pure cultured strain was identified to be Phellinus sp. In the flask culture, the optimum culture conditions for the mycelial production were obtained after cultivation of 8 days at inoculum level of 5%(v/v), media volume of 70 mL, 150 rpm, initial pH 6, and temperature of $30^{\circ}C$. Optimum medium composition from the response surface analysis were determined to be glucose 12.12 g/L, sucrose 12.12 g/L, yeast extract 11.15 g/L, malt extract 11.15 g/L, $KH_2PO_4$ 0.855 g/L and $CaCl_2$ 0.855 g/L. The production of the mycelia after 4 and 8 days of cultivation was 1.95 and 9.89 g/L, respectively. The maximum specific growth rate and productivity were $0.020\;hr^{-1}$ and 1.25 g/L/day, respectively. Among the three different culture systems for the growth of mycelia, the maximum mycelial dry weight of 7.5 g/L was obtained after cultivation of 4 days in the air-lift fermentor under aeration rate of 2.5 vvm. The maximum specific growth rate and productivity were $0.033\;hr^{-1}$ and 1.9 g/L/day, respectively, which were about 1.7 and 4.2 times higher than those of flask culture.

• Korean Journal of Environmental Agriculture
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• v.20 no.3
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• pp.180-185
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• 2001

Control effects of phosphorous acid were investigated on Phytophthora blight of red pepper plants in greenhouse and field. In vitro test, the mycelial growth of Phytophthora capsici was inhibited by the phosphorous acid more than 97% at 1,000 ${\mu}g$ and 10,000 ${\mu}g$ a.i./mL in the liquid and solid culture, respectively. At concentration of 10 ${\mu}g$ a.i./mL of phosphorous acid, in the liquid culture the mycelial growth of P. capsici was inhibited 46.2%, however inhibited only 4.9% on the soild culture. Zoosporangial formation was also inhibited 89.1% by phosphorous acid at 100 ${\mu}g$ a.i./mL. Phosphorous acid affected more zoosporangial formation of P. capsici than its mycelial growth. At the concentrations of 10,000, 1,000 and 100 ${\mu}g$ a.i./mL of phosphorous acid, germination of zoosporangia was inhibited 100, 84.3 and 44.2%, respectively. Mycelial growth and zoosporangial formation of P. capsici were little affected at the concentration of 10 ${\mu}g$ a.i./mL of phosphorous acid. Cermination of zoosporangia was also little affected at this concentration, however growth of the germ tubes was inhibited and the abnormal mycelial growth was observed. Phosphorous acid suppressed the incidence of Phytophthora blight of red pepper plants up to $77.0{\sim}62.0%$, in greenhouse. Phosphorous acid suppressed the incidence of Phytophthora blight of red pepper plants up to 54.0% at the conventional culture in field. Treatments of phosphorous acid increased up to 113% in height, 135% in number of fruit, and 129% in weight of fruit.

• Journal of Mushroom
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• v.10 no.2
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• pp.63-67
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• 2012

This study of afterripening conditions during oyster mushroom (Suhanneutari 1ho) cultivation in bottles was investigated. Medium materials were used poplar-sawdust (68%), cotton seed peel (16%), Beet pulp (8%) and cotton seed cake (8%). Mix of materials was used as a percentage of the volume and to adjust moisture content (67%). Autoclaved mediums were placed in low temperature storage ($20^{\circ}C$) and then moved in inoculation room and conducted mechanical inoculation. Mycelial culture temperature was maintained at $20{\sim}21^{\circ}C$ and cultured during 18 days. The afterripening period were 6days, 9days, 12days and 15 days at $25{\sim}27^{\circ}C$. The yield of fruit body was higher for 9 days (163.1g/bottle) and 12 days (160.7g/bottle) than that of other afterripening period. Second, in the changes in moisture content of the medium according to the afterripening period, no significant changes were observed during mycelial grwoth. The longer afterripening period was showed slightly lower weight of media. The moisture content of media after harvest at afterripening for 9 days had the biggest reduction than any other treatments. In addition, weight of media and yield of afterripening for 9 days were the lowest and highest, respectively.

• Journal of Mushroom
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• v.21 no.3
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• pp.179-184
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• 2023

The development of automated bottle cultivation systems has facilitated the large-scale production of Pleurotus ostreatus, a commonly cultivated oyster mushroom species in South Korea. However, as the consumption of this product is decreasing and production quantities are exceeding demand, farmers are seeking various other mushroom types and cultivars. In response to this, we have developed a new oyster mushroom cultivar named 'Sena'. This high-yielding cultivar has a white pileus and excellent quality. The white oyster mushroom cultivars 'Goni' and 'Miso' were selected as parental strains from the genetic resources of the National Institute of Horticultural and Herbal Science's Mushroom Division. By crossing their monokaryons, hybrids were developed and subjected to cultivation trials and characteristic evaluations to select the superior cultivar. The optimal temperature for 'Sena' mycelial growth is 25-30℃, with inhibition occurring at temperatures above 30℃, whereas the temperature for mushroom growth is 14-18℃. The mushrooms grow in clusters, with the white pileus having a shallow funnel shape. Optimal mycelial growth occurs in malt extract agar medium. When cultivated in 1,100 cc bottles, the 'Sena' cultivar had 35 available individuals, surpassing the number 16 available from the control cultivar 'Goni'. The yield per bottle also increased by approximately 157 g, a 24% increase over the control cultivar amount. When 300 g samples of harvested mushrooms were packed and stored at 4℃ in a cold storage facility for 28 days, the weight loss rate of 'Sena' was approximately 4.22%, lower than that of 'Goni'. Moreover, the changes in pileus and stipe whiteness (measuring 6.99 and 8.33, respectively) were also lower than those of the control cultivar. Since the appearance of a white cap is crucial for quality assessment, the 'Sena' cultivar is superior to the 'Goni' cultivar in terms of both weight and quality after undergoing low-temperature storage.

• Korean journal of applied entomology
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• v.15 no.3 s.28
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• pp.153-159
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• 1976

Present paper was attempted to investigate the effects of the light on the sclerotium formation of some isolates of Sclerotinia sclerotiorum(Lib.) do Bary from lettuce, cucumber and rape. The investigations were performed in the both aspects inducing sclerotial primordia from the mycelial colony and developing such primordia. The cultures were grown on potato-dextrose agar and were treated with day-light fluorescent lamps. In the continuous light illumination for 21 days, numbers of sclerotial primordia and matured sclerotia were increased with increasing the light intensity up to about 500 Lux, but on the contrary the dry-weight of matured sclerotia was decreased. In the 800 Lux illumination, induction of the primordia was extremely depressed, and then matured sclerotia were almost not produced. Short-time illumination for 48 hours, although the light intensity was as high as 5000 Lux, increased the numbers of sclerotial primordia and matured sclerotia. Dry-weight of matured sclerotia, however, was slightly increased only at low intensity of 160 Lux. On the other hand, the light shock which u·as alternatively on-of light every one minute for 48 hours increased the number and dry-weight of sclerotia produced, but the former was more effective at 500 Lux shock and the later more effective at 160 Lux shock.

• Journal of radiological science and technology
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• v.24 no.1
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• pp.75-82
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• 2001

Effect of single pre-administration of Cordyceps militaris(Cm) extract on the survival ratio, body weight and organ weight changes and blood cell counts after whole-body ${\gamma}-irradiation$ were investigated. The single pre-administration of Cm extract at 24 hrs before ${\gamma}-irradiation$ increased the 40-day survival ratio of irradiated mice from 60.1% to 71.4%. The administration of Cm extract completely prevented weight reductions of spleen and thymus produced by ${\gamma}-irradiation$ (P<0.01, P<0.05). Similar but somewhat less radioprotective effect was also found In the testis of the Cm treated mice. The administration of Cm extract retarded the reduction of both leukocyte and lymphocyte counts occured during the first 7 days and accelerated the recovery of the counts thereafter. The exrtract also acclerated the recovery of the erythrocyte counts occured after the day 21th. SDS-polyacrylamide gel electrophoresis of the soluble proteins extracted from various organs did not reveal differences to any extent in all groups except in the livers of the irradiated and extract treated groups, in which some proteins were missing or less present. Also, the result of general intra and extra mycelial enzyme assays with Cm, extramycelial enzyme activity was relatively higher than the intramycelial enzyme, Cm appeared to indicate that ${\alpha}-amylase$ was the highest among the enzymes and gluosidase and chitinase were followed. Since the spleen, thymus and testis have been well known as radiosensitive organs, the protective action of Cm extract on irradiated mice may be responsible for its enhancing recovery of these organs. Although the exact mechanism in protective effect of Cm extract on irradiated mice is not clear yet, the present study is the first report regarding the Cm which was tested and found to be a potential radioprotective agent.