• The Korean Journal of Mycology
• /
• v.14 no.2
• /
• pp.141-148
• /
• 1986

The optimal conditions for high yields of mycelial protoplasts from P. cornucopiae were established. The concentraion of enzyme system containing Novozym 234, ${\beta}-D-glucanase$ and ${\beta}-glucuronidase$ was $5mg\;ml^{-1}$ each. The osmotic stabilizer most effective for protoplast isolation was O.6 M sucrose. The optimal reaction time of mycelium with the lytic mixture was 90 min in a shaking condition at 120 strokes $min^{-1}$. When the myelium of P. cornucopiae was cultured for 4 days on mushroom complete medium at $28^{\circ}C$, the formation of protoplast was effective. When the pH of the digestion mixture with O.6 M sucrose as stabilizer varied between pH 4.0 and 7.0, the production of protoplasts was effective in phosphate buffer (pH 6.2) and Na-maleate buffer (pH 5.0). Generally, phosphate buffer was more effective for protoplast isolation than Na-maleate buffer, but 0.6 M sucrose osmotic stabilizer without adjusting pH was most effective. Using these conditions, protoplasts from P. cornucopiae were obtained at a ratio $1{\times}10^7\;ml^{-1}$.

• Journal of Mushroom
• /
• v.16 no.3
• /
• pp.198-202
• /
• 2018

'Yong-A' was bred by Jeollanamdo Agricultural Research and Extension Services in 2015. It was primarily selected through monospore crossing between JNM21008 and JNM21013 in 2009. The strain is named as JNM-Mi-194 and 'Yong-A', showing major characteristics with good production yield. The cultivation characteristics, yield potential, and fruiting body characteristics of 'Yong-A' are as follows; The wrinkle of the fruiting body was of branching type its shape was wave type. MCM, YM, Malt, and PDA media were suitable for growth of this cultivar. The number of effective stipes was 13 ea/0.9 kg. The minor axis of pileus was 5 cm and the major axis was 9 cm. The yield was 291 g per plastic bag (0.9 kg). Yong-A required 60 days for mycelial running at $20^{\circ}C$. The growth and primordial period required 24 days, which was shorter than that of JNM-Mi-21002 (the conventional cultivar). Somatic incompatibility was observed between parental lines and Yong-A. Analysis of genetic diversity in the new variety 'Yong-A' showed a different profile compared to that of the parent strain when Random Amplified Polymorphic DNA primers were used.

• The Korean Journal of Mycology
• /
• v.31 no.1
• /
• pp.1-7
• /
• 2003

One hundred fifty one specimens of Beauveria spp. from 19 different locations were collected from September 1 to August 31, 2002. Most of the isolates were identified as Beauveria. bassiana. Cordyceps staphylinidaecola collected from Mt. Obong in Chunchon City covered the host with mycelia which were produced 1 to 4 stromata along with asexual spores. The size of bright yellow ununiform stromata were about 45 mm and the head about $17mm{\times}4mm$. Perithecia completely immersed were $530{\sim}550{\times}290{\sim}300{\mu}m$ in size and mainly scattered on the head. Ascospore produced in asci in the size of $400{\sim}450{\times}4{\sim}5{\mu}m$ developed thread-like secondary spores, which were directly separated into secondary conidial spores. Conidia produced at apical portion of synnemata were $2.6{\sim}3.4{\times}1.2{\sim}1.9{\mu}m$ in size. High density of mycelium was observed at $25^{\circ}C$ ranged from pH 6.5 to 8.5 after 11 days of inoculation. It took 15 to 18 days after inoculation to fully grow on the medium mixed brown rice with pupa. Mycelium developed stromata on the medium 30 days after completion of mycelial growth, where perithecia were produced in 40 days.

• Korean Journal of Food Science and Technology
• /
• v.30 no.2
• /
• pp.348-355
• /
• 1998

The developments of various processed foods and the high quality dried fruits, in particular, are urgently needed for the enhancement of fruit consumption and their competitive values. Therefore, in this study, three variables by three level factorial design and response surface methodology were used to determine optimum conditions for osmotic dehydration of kiwifruit. The relationships of moisture losses, solid gains, weight reductions, sugar contents, titratable acidities and vitamin C contents depending on changes with temperature, sugar concentration and immersion time were investigated. The moisture loss, solid gain, weight reduction and reduction of moisture content after osmotic dehydration were increased as temperature, sugar concentration and immersion time increased. The effect of concentration was more significant than those of temperature and time on mass transfer. Sugar content was increased by increasing sugar concentration, temperature, immersion time during osmotic dehydration. Titratable acidity and vitamin C content were increased by decreasing temperature, immersion time and increasing concentration during osmotic dehydration. The regression models showed a significant lack of fit (P>0.05) and were highly significant with satisfying values of $R^2$. At the given conditions such as $66{\sim}69%$ moisture content, above $24^{\circ}Brix$ sugar content and more than 23 mg% vitamin C, the optimum condition for osmotic dehydration was $37^{\circ}C,\;55^{\circ}Brix$ and 1.5 hour.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.08a
• /
• pp.250-250
• /
• 2013

단일벽 탄소나노튜브(Single-walled nanotubes, SWNTs)는 나노스케일의 크기와 우수한 물성으로 인하여, 전자, 에너지, 바이오 분야로의 응용이 기대되고 있다. 특히 SWNTs의 직경을 제어하게 되면 튜브의 전도성 제어가 훨씬 수월하게 되어, 차세대 나노전자소자의 실현을 앞당길 수 있으며 이러한 이유로 많은 연구들이 현재 행해지고 있다. SWNTs의 직경제어 합성을 위해서는 현재 열화학기상증착법(Thermal chemical vapor deposition; TCVD)이 가장 일반적으로 이용되고 있으며, 합성 촉매와 합성되는 튜브의 직경과의 크기 연관성이 알려진 후로는, 촉매의 크기를 제어하여 SWNTs의 직경을 제어하고자 하는 연구들이 활발하게 보고되고 있다. 특히, 촉매 나노입자의 직경이 1~2 nm 이하로 감소될 경우, SWNTs의 직경 분포가 어떻게 변화할 것인지가 최근 가장 중요한 관심사로 남아 있으나, 이러한 크기의 금속입자는 나노입자의 융점저하 현상이 발현되는 영역이므로, SWNTs의 합성온도 영역에서 촉매 금속입자는 반액체(Semi-liquid) 상태로 존재할 것으로 추측하고 있다. 본 연구에서는 고온의 SWNTs 합성환경에서 금속나노촉매의 유동성을 제한하기 위하여 나노사이즈의 기공이 규칙적으로 정렬된 다공성 물질인 제올라이트를 촉매담지체로 이용하였고, 이 때 다양한 합성변수가 SWNTs의 직경에 미치는 영향을 살펴보고자 하였다. SWNTs의 합성을 위해 실리콘 산화막 기판 위에 제올라이트를 도포한 후, 합성 촉매로서 전자빔증발법을 통하여 수 ${\AA}$에서 수 nm 두께의 철 박막을 증착하였다. 합성은 메탄을 원료가스로 하여 TCVD법으로 실시하였다. 주요변수로는 제올라이트 종류, 증착하는 철 박막의 두께, 합성온도를 설정하였으며, 이에 따라 합성된 SWNTs의 합성수율 및 직경분포의 변화를 체계적으로 살펴보았다. SWNTs의 전체적인 합성수율의 변화는 SEM 관찰결과를 이용하였으며, SWNTs의 직경은 AFM 관찰 및 Raman 스펙트럼의 분석에서 도출하였다. 실험결과, 제올라이트 종류에 따라서는 명확한 튜브직경 분포의 변화 없이 비교적 좁은 직경분포를 갖는 SWNTs가 합성되었으며, 합성온도가 $850^{\circ}C$ 이하로 감소되면 합성수율이 현저히 감소되는 것을 알 수 있었다. 촉매박막의 두께가 1 nm 이상인 경우에서는 직경 5 nm 전후의 나노입자가 형성되었으며, 이때 SWNTs의 합성수율은 높았으나 다양한 직경의 튜브가 합성이 된 것을 확인할 수 있었다. 반면, 촉매입자의 크기가 2 nm 이하에서는 합성수율은 다소 저하되었으나, SWNTs의 직경분포의 폭이 상대적으로 훨씬 좁아지는 것을 알 수 있었다. 추후, 극미세 촉매와 저온합성 환경에서의 합성수율 향상을 위한 합성공정의 개량이 지속적으로 요구된다.

• Journal of Mushroom
• /
• v.14 no.4
• /
• pp.202-206
• /
• 2016

Oyster mushrooms are widely cultivated and consumed in Korea. P. ostreatus 'Suhan(ASI 2504)' is an ideal cultivar for mushroom farmers due to its dark pileus and thick stipe; however, as it is very sensitive to environmental conditions, an alternative cultivar is required. To develop a new cultivar, parental strains 'Suhan(ASI 2504)' and 'ASI 0665 (Heuktari)' were selected from various collected strains according to morphological characteristics. P. ostreatus 'Soltari' was developed by DiMon crossing between the dikaryotic strain 'Suhan' and the monokaryotic strain derived from 'Heuktari'. Thirty-eight of the 100 crossed strains were selected following analysis of mitochondrial genetic characteristics, and 'Soltari' was ultimately selected by continuous cultivation tests. The mitochondrial DNA profile of 'Soltari' was found to be the same as that of 'Heuktari, and a nuclear DNA profile of 'Soltari' was similar as those of the parental strains, 'Suhan' and 'Heuktari.' 'Soltari' mycelium grows adequately in moderate to high temperatures of $12-20^{\circ}C$, although its optimum temperature was found to be $30^{\circ}C$. Fruiting body production per 1.1-L cultivation bottle was approximately 158.8 g. Its stipe length and thickness were comparable to those of diameter and thickness were somewhat lower (42.72 vs. 51.33 mm and 18.18 vs. 22.46 mm, respectively). 'Soltari' was found to be more resistant to high $CO_2$ atmosphere than 'Suhan', and the color of the pileus of 'Soltari' was dark gray at high temperature. Therefore, it is suggested that this new cultivar 'Soltari' is a good alternative cultivar and will contribute to energy saving in oyster mushroom farms.

• Korean Journal of Food Science and Technology
• /
• v.30 no.2
• /
• pp.385-390
• /
• 1998

The effect of agglomeration treatment was examined to prevent the parched cereal powder from clumping when it is blended with water. Parched cereal powder was composed of 66.9% carbohydrate, 7% water, 12.1% crude protein, 12.1% crude fat and 1.9% ash, respectively. Particle size of parched cereal powder was generally enlarged by agglomeration treatment. This phenomenon was confirmed by particle size analyzer and microscopic observation. The color of agglomerated sample was shown to be slightly darker than the untreated sample. The water absorption indices of agglomerated samples which were steamed for 2min and re-dried were significantly increased as compared with the untreated sample. The water solubility indices of agglomerated samples showed generally lower values than those of untreated samples. In views of quality and processing time, the optimum condition of agglomeration treatment for manufacturing well-dispersable parched cereal powder in water was 15min re-drying after 2min steaming. It is concluded that the agglomeration treatment improves the dispersibility of parched cereal powder and thus facilitates the intake of it after mixing with water.