• Bulletin of the Korean Chemical Society
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• 제35권8호
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• pp.2257-2262
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• 2014

$C_{60}$ is widely investigated because of its unique structure. But its applications in solid propellant seem to be relatively neglected. $C_{60}$ has more outstanding features than carbon black which is widely used as a catalyst ingredient of solid propellant. To combine the advantages of fullerene and lead salts, another good composite in propellant catalysts, we synthesized a kind of fullerene phenylalanine lead salt (FPL) and explored its thermal performances by differential thermal analysis (DTA) and thermogravimetry analysis (TGA). The results show it undergoes four exothermic processes started from 408 K. Combined TGA and X-ray diffractometer (XRD), the decomposition mechanism of FPL was derived by TG-IR and comparing IR spectra of FPL and its residues after burned to $327^{\circ}C$, $376^{\circ}C$ and $424^{\circ}C$, respectively. Effect of FPL on the decomposition characteristic of hexogen (RDX), a type of explosive in propellant, has been investigated using DTA at different heating rate, which shows the decomposition temperatures of the explosive are all reduced by more than 20 K. The corresponding activation energy ($E_a$) is decreased by $30kJ{\cdot}mol^{-1}$. So FPL has potential application as a combustion catalyst in solid propellant.

• Food Science and Biotechnology
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• 제15권5호
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• pp.814-816
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• 2006

Monacolin K (MK) was produced on soybean using Monascus ruber GM011 by a two-stage-fermentation process. The optimal temperature was identified as $28^{\circ}C$. Higher yield was obtained by multiple-level-temperature cultivation than by single-level-temperature cultivation. The highest yield of total MK, 4.810 mg/g dry soybean product, was attained after 30 days of solid-state fermentation. No citrinin could be detected in the fermented soybean.

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1421-1430
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• 2009

With an aim to evaluate dye decolorization by white rot fungus on natural living conditions, reproducing by solid-state fermentation, the process of triphenylmethane dyes decolorization using the white rot fungus P. ostreatus BP, cultivated on rice straw solid-state medium, has been demonstrated. Three typical dyes, including malachite green, bromophenol blue, and crystal violet, were almost completely decolorized by the fungus after 9 days of incubation. During the process of dye decolorization, the activities of enzyme secreted by the fungus, and the contents of soluble components, such as phenolic compounds, protein, and sugar, changed regularly. The fungus could produce ligninolytic, cellulolytic, and hemicellulolytic enzymes and laccase was the most dominant enzyme in solid-state medium. Laccase, laccase isoenzyme, and the laccase mediator could explain the decolorization of malachite green, bromophenol blue, and crystal violet by the fungus in solid-state medium, respectively. It is worth noting that the presence of the water-soluble phenolic compounds could stimulate the growth of fungus, enhance the production of laccase, and accelerate dye decolorization.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.263-267
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• 2003

Solid-state fermentation of lovastatin by Aspergillus terreus was investigated using commercially available 1.2 L polypropylene bottle designed for mushroom cultivation. Moist solid raw materials such as com, rice, and soy bean were tested and com was found to be most suitable for an economical production of lovastatin. 50% or higher water addition prior to the sterilization of com was effective for the maximal lovastatin production. About 0.5% (w/w) lovastatin content in dried cells and corn mass was obtained after 20 days of solid-state fermentation at 30$^{\circ}C$. For safety concerns, aflatoxin Bl and citrinin levels after fermentation were assayed but they were not detected. Lovastatin containing cells and corn residue after fermentation were autoclaved, dried, crushed, and fed to chicken for a period of 3 weeks. Approximately 20% reduction of blood cholesterol level of chicken was observed.

• Journal of Microbiology and Biotechnology
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• 제11권1호
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• pp.13-16
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• 2001

Maltose and soluble starch were used as secondary sources of carbon for glucoamylase production by Aspergillus awamori in solid state fermentation. During batch cultivation, maltose above 2.5%(w/w) repressed glucoamylase production, but, by adding either 2.5% (w/w) maltose or 1.25% (w/w) soluble starch to fed-batch cultivations, glucoamylase activity was increased by 15% and 170% over standard medium, respectively. The data showed that maltose is a weak inducer of glucoamylase production in solid stat fermentation.

• Mycobiology
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• 제38권2호
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• pp.137-143
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• 2010

The production of conidia of entomopathogenic Beauveria bassiana by solid-state fermentation was studied for the development of a biocontrol agent against aphid Myzus persicae. The optimal conditions for conidia production on polished white rice were 40% moisture content, $25^{\circ}C$ culture temperature, 2-day-old seeding culture grown in 3% corn meal, 2% rice bran, 2% corn steep powder medium, initial conidia concentration of $10^7$ conidia/g in the wet rice, 10% inoculum size, and use of a polyethylene bag as a container. The polyethylene bag containing inoculated rice was hand-shaken every 12 hr during fermentation. Using optimal conditions, the maximum conidia production obtained was 4.05 g conidia/100 g dry rice after 14 days of cultivation, a rate 2.83 times higher than conidia yield of pre-optimization.

• Mycobiology
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• 제42권4호
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• pp.346-352
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• 2014

Recently, the Q biotype of tobacco whitefly has been recognized as the most hazardous strain of Bemisia tabaci worldwide, because of its increased resistance to some insecticide groups. As an alternative control agent, we selected an Isaria javanica isolate as a candidate for the development of a mycopesticide against the Q biotype of sweet potato whitefly. To select optimal mass production media for solid-state fermentation, we compared the production yield and virulence of conidia between 2 substrates (barley and brown rice), and we also compared the effects of various additives on conidia production and virulence. Barley was a better substrate for conidia production, producing $3.43{\times}10^{10}$ conidia/g, compared with $3.05{\times}10^{10}$ conidia/g for brown rice. The addition of 2% $CaCO_3+2%$ $CaSO_4$ to barley significantly increased conidia production. Addition of yeast extract, casein, or gluten also improved conidia production on barley. Gluten addition (3% and 1.32%) to brown rice improved conidia production by 14 and 6 times, respectively, relative to brown rice without additives. Conidia cultivated on barley produced a mortality rate of 62% in the sweet potato whitefly after 4-day treatment, compared with 53% for conidia cultivated on brown rice. The amendment of solid substrate cultivation with additives changed the virulence of the conidia produced; the median lethal time ($LT_{50}$) was shorter for conidia produced on barley and brown rice with added yeast extract (1.32% and 3%, respectively), $KNO_3$ (0.6% and 1%), or gluten (1.32% and 3%) compared with conidia produced on substrates without additives.

• 한국식품조리과학회지
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• 제22권3호통권93호
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• pp.337-345
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• 2006

영지버섯, 장수버섯, 상황버섯을 곡물에서 배양하는 고체재료 발효방법을 개발하였으며, 발효된 곡물을 이용하여 즙장을 제조하고 관능검사를 실시함으로써 기능성식품으로서의 이용 가능성을 검토하였다. 담자균의 고체재료 배양을 위하여 사용된 곡물의 특성을 조사한 결과, 냉침시간에 따른 곡물의 수분함량 변화는 메주콩이 10시간, 보리는 6시간, 율무가 4시간, 밀이 12시간만에 최대수화 시간에 도달하였으나 최종 수분함량이 $30{\sim}48\;%$로서 버섯 균사체가 생장하기에는 부족한 수분함량을 보였다. 담자균사체의 대량배양 조건실험을 실시한 결과, 냉침에 의해 최대수화에 도달한 곡물을 배양용기에 담고, 액체배양 후 균질화한 담자 균사체를 곡물에 접종함으로써 접종초기 짧은 시간에 균사가 완전히 활착되도록 할 수 있었다. 또한 균사 배양중기에 멸균 증류수를 첨가함으로써 균사의 활력을 유지시킬 수 있었다. 곡물에 배양된 담자균의 균사체량을 나타내는 glucosamine의 함량은 장수버섯과 상황버섯이 배양된 율무에서 특히 높은 함량을 나타내었고 영지버섯이 배양된 곡물의 경우는 밀에서 가장 높은 함량을 나타내었다. 담자균사체에 의해 발효된 곡물을 이용하여 즙장을 제조하고 관능검사를 실시한 결과, 영지버섯 균사체가 배양된 곡물이 가장 우수하였는데, 그 중 콩에 율무를 혼합한 시료가 가장 우수한 것으로 나타났으며, 숙성기간이 길어짐에 따라 전반적으로 기호도가 약간씩 상승하였다.

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.525-531
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• 2010

This work was aimed at utilizing rice bran as a substrate for $\beta$-carotene production by Rhodotorula glutinis DM 28 under optimized conditions of solid-state fermentation. The biomass and $\beta$-carotene content of Rhodotorula glutinis DM 28 grown on rice bran as a sole substrate under solid-state fermentation were 54 g/kg rice bran and 1.65 mg/kg rice bran, respectively. Its biomass and $\beta$-carotene content, however, could be improved by 60% and 30%, respectively, using the Central Composite Design for the optimization of its cultivation conditions. The optimized conditions obtained were a pH of 5, a moisture content of 70% (w/w), and a carbon-to-nitrogen ratio of 4. Under these conditions, rice bran containing R. glutinis DM 28 had nutritional values of $\beta$-carotene, protein, and fat higher than those of rice bran alone. Yeast-grown rice bran could be suitable, therefore, to use as a $\beta$-carotene-enriched supplement in animal feeds.

• Journal of Microbiology and Biotechnology
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• 제23권4호
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• pp.489-498
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• 2013

A new Bacillus strain degrading starch, named Bacillus sp. UEB-S, was isolated from a southern Tunisian area. Amylase production using solid-state fermentation on millet, an inexpensive and available agro-resource, was investigated. Response surface methodology was applied to establish the relationship between enzyme production and four variables: inoculum size, moisture-to-millet ratio, temperature, and fermentation duration. The maximum enzyme activity recovered was 680 U/g of dry substrate when using $1.38{\times}10^9$ CFU/g as inoculation level, 5.6:1 (ml/g) as moisture ratio (86%), for 4 days of cultivation at $37^{\circ}C$, which was in perfect agreement with the predicted model value. Amylase was purified by Q-Sepharose anion-exchange and Sephacryl S-200 gel filtration chromatography with a 14-fold increase in specific activity. Its molecular mass was estimated at 130 kDa. The enzyme showed maximal activity at pH 5 and $70^{\circ}C$, and efficiently hydrolyzed starch to yield glucose and maltose as end products. The enzyme proved its efficiency for digesting raw cereal below gelatinization temperature and, hence, its potentiality to be used in industrial processes.