• 한국작물학회지
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• 제45권1호
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• pp.32-37
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• 2000

The in vitro culture of rice panicles is a culturing technique only panicle without other organs in culture solution containing organic substance, so that would be useful to study how assimilate supply affects grain development and maturation. To find the optimum stage for in vitro culture, rice panicles grown in greenhouse were sampled periodically after anthesis and cultured in nutrient medium. The panicles older than 1 weeks after anthesis had produced normal grains. Grain-filling was apparently dependent upon sucrose concentration (8-12 %) in medium, but not affected by nitrogen concentration supplied with glutamine. As far as rice panicle was supplied with sucrose and N in nutrient medium, grains continued accumulation of dry matter and maturation regardless to light condition. Considerably, grain-filling was improved when panicles were positioned horizontally inside flask, so that each grain was partially submerged to nutrient medium.

• Journal of Advanced Marine Engineering and Technology
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• 제24권4호
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• pp.526-534
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• 2000

In this study, the characteristics of exhaust emissions in medium speed diesel engine under various operating conditions were investigated through experiments to derive the optimum conditions for minimizing the exhaust emissions, especially, nitrogen oxides. The 355 KW$\times$1200 rpm medium speed diesel engine was intensively examined to investigate the trend of exhaust emissions in case that the parameters affecting combustion conditions such as fuel injection timing, intake air temperature and pressure, engine speed and load were changed. The exhaust emissions for 9 sets of medium speed diesel engine were analyzed in addition. From this study, NOx level could be reduced by 30~50% through the adjustment of retarded fuel injection timing, lowered intake air temperature and increased charging air pressure.

• 한국자원식물학회지
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• 제11권1호
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• pp.1-8
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• 1998

This study was conducted to establish mass propagation system from the axillary bud culture of chrysanthemum zawadskii H. which was used as material of medicinal plants. Shoot egeneration was better on MS medium with NAA and BA. The optimum concentraions of growth regulator for shoot regeneration differed depending on accessionsof C. Zawadskii. Shoot regeneration in Keungucheolcho was better on MS Medium with NAA 0.01mg/1 and BA 0.1mg/1 while Hyangrobonggucheocho was better with NAA 0.1mg/1and BA 0.3mg/1. Addition of NAA into medium was effective for induction of root from shoots regenerated. Shoot multiplcation was more effective when 10mg/1 spermine was added into medium than when other polyamines were treated ino medium . Randomly and specifically amplified polymorphic DAC banding patterns based on polymerase chain reaction (PCR) analysis were used to assess the genetic variation of plants regenerated from in vitro culture.

• Journal of the Korean Wood Science and Technology
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• 제31권6호
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• pp.60-66
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• 2003

Mycelial growth of L. edodes by supplement nutrition of softwood was studied on a sawdust medium. The sawdust used was from the following softwood species : Larix leptolepis, Pinus densiflora and Pinus koraiensis. The added nutritions consisted of carbon nutritions(sucrose, active carbon, xylose, glucose, paper pellet), nitrogen nutritions(potassium nitrate, ammonium chloride, asparagine, glutamic acid) and vegetable oil(rice bran oil). The sawdust medium was a mixture of 76% sawdust, 20% rice bran, 3% carbon nutrition, 0.4% nitrogen nutrition and 0.6% calcium carbonate. Following addition of carbon and nitrogen nutritions on the sawdust medium proved most suitable : L. leptolepis (glucose, glutamic acid), P. densiflora (active carbon, asparagine) and P. koraiensis (xylose, glutamic acid). The highest mycelial growth was obtained from sawdust medium of optimum condition with 97% of L. leptolepis, 110% of P. densiflora and 98% of P. koraiensis. This study has provided useful preliminary information for the cultivation of L. edodes.

• 한국미생물·생명공학회지
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• 제7권3호
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• pp.157-164
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• 1979

Aspergillus 속균중 Asp. awamori U-3가 acid protease의 생산능이 우수함으로 효소생산에 미치는 배양조건 및 조효소의 특성을 검토하고 다음과 같은 결과를 얻었다. 1. 최적배양온도는 3$0^{\circ}C$, 최적배양시간은 72 시간, 최적첨수량은 wheat bran medium 에서는 100~120 %, defatted rice bran medium 에서는 100~130%이었다. 2. 명종 성분중 wheat bran medium에는 KN $O_3$, glutamic acid, glucose 가, defatted rice bran me-dium 에는 KN $O_3$, (N $H_4$)$_2$S $O_4$, glucose, lactose, K $H_2$P $O_4$ 및 MgC $l_2$의 첨가가 특히 효과적이었으며, wheat bran medium 에서 가장 효과적인 glucose, KN $O_3$와 glutamic acid의 최적 첨가농도는 명명 3.0~4.0%, 0.2~0.4%, 1.0 %이었다. 3. 본효소의 작용 최적 pH는 2.4, 최적온도는 45$^{\circ}C$내외, 안정 pH 범위는 2.0~5.0이고, 5$0^{\circ}C$ 이하에서는안정하나 그 이상에서는 급격하게 불활성화 되었다. 4. 본효소에 대한 명종 무기염류의 내열효과를 검토한바 CaC $l_2$와 CaS $O_4$ 가 약간의 내열효과를 나타내었다. 5. 내열제를 첨가하고 6$0^{\circ}C$에서 10~30 분간 처리할때 20분 이상에서는 효소의 잔존활성이 크게 감소되었고, 내열제로서 CaC $l_2$와 CaS $O_4$ 를 첨가할 때 다같이 8$0^{\circ}C$에서는 내열효과는 거의 없었다.

• 한국식품영양학회지
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• 제11권6호
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• pp.673-677
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• 1998

A inhibitor acting on substrate proteolytic enzyme was isolated from culture broth of Streptomyces sp. SK-862, which had been isolated from soil in Wonju City, by using the colloidal agar medium. The optimum culture temperature and initial pH for the production of the protease inhibitor was 28$^{\circ}C$ and pH 8.5, respectively. The optimum culture medium was composed of 1.5% glucose, 0.5% peptone, 0.1% K2PHO4, 0.05% CaCO3 and initial pH 8.5. The inhibitor production was maximum when the strain was incubated in shaking incubator at 70 strokes for 60 hours.

• 한국식품영양학회지
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• 제11권6호
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• pp.640-646
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• 1998

For the production of nonprotein $\alpha$-glucosidase inhibitor from the Streptomyces sp. NS15 strain, effects of initial optimum pH, nitrogen sources, carbon sources, cationic metal ions, agitation speed and aeration rate were investigated. Initial optimum pH of medium was 7.0. The most effective nitrogen and carbon sources were soybean meal 2.0%(w/v) and glucose 1.6%(w/v), respectively. The cationic metal ins had no stimulating effect on inhibitory activity of $\alpha$-glucosidase except Fe2+. Agitation speed and aeration rate were effective at 400rpm and 1vvm, respectively. In the jar-fermenter cultivation for 4 days under optimal culture conditions, the culture broth showed the inhibitory acitivity of 3,200units/ml, which is 25 times higher than that of basic medium (CYM) for porcine intestinal $\alpha$-glucosidase. The inhibitory activity of $\alpha$-glucosidase reached about 3,200units/ml after 4 days of cultivation and decreased gradually for a further two days.

• 한국식품영양과학회지
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• 제25권3호
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• pp.513-518
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• 1996

In order to investigate the characteristics of alcohol fermentation by Saccharomyces cerevisiae, compositions and free sugar content of dried riped pumpkin powder were determined. The proximate compositions of ripe pumpkin powder were as follows: moisture 11.98%, total sugar 62.18%(dried weight basis 70.64%), protein 13.38%, lipid 0.85%, fiber 7.07% and ash 4.54%. The compositions of free sugar in well ripe pumpkin were: glucese 85.36mg/g, fructose 40.68mg/g, sucrose 68.25mg/g, lactose 18.60mg/g and maltose 3.82mg/g. The optimum conditions for alcohol fermentation by S. cerevisiae were as follows; incubation temperature of 3$0^{\circ}C$, initial pH of 6.0, ripe pumpkin powder concentration of 10% and cells inoculation of 1.3$\times$$10^{6}$ cells/ml liquid medium. Ethanol production under the optimum conditions was 5.95g/100g in liquid medium containing 10% ripe pumpkin powder after 4 days incubation.

• 한국미생물·생명공학회지
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• 제21권6호
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• pp.609-614
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• 1993

The optimum conditions for the submerged mycelial culture of Lentinus edodes SR-1 were elucidated to be incubation temperature of 25C, initial pH 4.0, agitation of 300 rpm, inoculation of 10.0%(v/v), and aeration of 1.0 v/v/m in TGY medium. The optimum c/n ratio and economic yield coeffcient for the submerged mycelial culture were 13.1:1 and 0.45 respectively. As the plant growth hormones test, SCM medium containing 0.5ppm of 2,4-dicholorophenoxyacetic acid increased mycelial yield in 1.1%, but 6-benzylaminopurine was not effective.

• Plant Resources
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• 제8권3호
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• pp.286-292
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• 2005

Shoot induction system was developed in the recalcitrant plant species, Brassica rapa ssp. rapifera by using optimum selection of profit organ, phytohormone combination, seedling age and kind of culture container. Out of in vitro cultured leaf segment, petiole, hypocotyl, and cotyledon with petiole, only cotyledon with petiole derived from 4 day-old seedlings induced multiple shoot. The optimum combination of auxin and cytokinin for the multiple shoot induction was MS medium containing 5mg/L BA and 0.5mg/L NAA. The major factors for multiple shoot propagation were part of plant organ, age of seedling, and ratio of auxin and cytokinin. In addition, shoot regeneration was promoted in the 100ml Erlenmeyer flask compared with the $90mm{\times}20mm$ Petri-dish. The induced shoots formed roots easy on MS medium containing 0.1mg/L IBA and the whole plants were successfully cultivated in soil.