• 미생물학회지
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• 제39권1호
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• pp.45-50
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• 2003

분자 생물학적 방법 인 DGGE를 이용하여 저온에서 김치가 발효되는 동안 관여하는 미생물의 다양성과 변화양상을 분석하였다. 김치를 저온 ($4^{\circ}C$)에서 발효시키는 60 일 동안 5 일 마다 시료를 채취하였으며, 채취한 김치 시료에서 genomic DNA를 추출하여 실험을 수행하였다. 김치 시료 genomic DNA로부터 16S rDNA의 V3영역을 증폭하여 DGGE를 수행한 결과에서 관찰된 amplicon들의 염기서열을 분석한 결과 저온에서 김치가 발효되는 동안 젖산균들이 주요 미생물 군집으로 나타났으며, 그 중에서도 Weissella koreensis가 발효 전 과정 동안, Lactobacillus sakei의 경우는 발효 10 일째부터, 그리고 Leuconostoc gelidurn은 발효30 일째부터 amplicon들의 농도가 진하게 나타나 이들이 저온에서 김치 발효 과정 동안의 우점종 균주들 임을 알 수 있었다.

• 한국의류산업학회지
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• 제15권4호
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• pp.635-641
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• 2013

This study examined the dye-properties of natural fabrics dyed with Coptis chinensis and Curcuma longa root fermented with fungi. The optimum culture conditions for the fermentation of microorganisms, the relationship between natural dye color and fermentation conditions were investigated. Two different medical herbs (ground to 80-100 mesh in size) were used as a natural dyeing source. Phellinus linteus (P. linteus), which can grow in different media, such as Agarmedium (only agar containing medium), maltose extract agar (MA) and potato dextrose extract agar (PDA) culture media, were isolated from the medium. P. linteus was confirmed to be the optimum microorganism for the fermentation of Coptis chinensis and Curcuma longa, and the MA medium was confirmed to be the best for culturing. When using the microorganism as the fermenting agent, $32^{\circ}C$ was found to be the optimum fermenting temperature for both natural colorants. Regarding the dyeing property of the fermented natural dye, silk was dyed quite darkly in an appearance by naked eye estimation and the K/S value in the color strength of silk reached a high level of 16 after the fermenting process. The washing fastness of dyed silk after treatment washing was reduced from 4 to under4 and indicates that dyed silk with fermented plant was not unsubstantial. The light fastness was 1 to 2, showing intended to maintain due to the fermentation process.

• Journal of Microbiology and Biotechnology
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• 제4권3호
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• pp.215-221
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• 1994

Two strains of yeast (RA-74-2 and RA-912) showing superior fermenting ability at a high temperature were isolated from soils and wastewaters by an enrichment culture method. Based on the morphological and physiological charateristics, the two strains were identified as Saccharomyces cerevisiae and Kluyveromyces marxianus, respectively. RA-74-2 was able to grow upto $43^{\circ}C$ and sustain similar fermenting ability in the temperatures range from 30 to $40^{\circ}C$. In addition, the sugar- and ethanol-tolerance of RA-74-2 were 30% (w/v) glucose and 10% (v/v) ethanol, which appeared to be higher than those of nine other industrial yeast strains currently being used in the alcohol factories. The thermotolerant ethanol fermenting yeast RA-912 showed identical growth in the temperatures range from 35 to $45^{\circ}C$ and was resistant to various heavy metals. The quality and quantity of byproducts of the isolated yeast strains in fermentation broth after fermentation at $40^{\circ}C$ and $45^{\circ}C$ were similiar with those obtained at $30^{\circ}C$. These results show that RA-74-2 can be adopted for the ethanol fermentation process where the expenses for cooling system is significant, and suggest that RA-912 may be applied in either SSF(simultaneous saccharification and fermentation) or Flash-fermentation process and RA-912 may be used as a gene donor for the development of thermotolerant ethanol-fermenting yeasts.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2006년도 Proceedings of The Convention of The Korean Society of Applied Pharmacology
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• pp.127-130
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• 2006

Coenzyme Q10(CoQ10) is a biological quinine compound that is widely found in living organisms including yeast, plants, and animals. CoQ10 has two major physiological activities:(a)mitochondrial electron-transport activity and (b)antioxidant activity. Various clinical applications are also available : Parkinson's disease, Heart disease, diabetes. Because of its various application filed, the market size of CoQ 10 is continuously expanding all over the world. A Japanese company, Nisshin Pharma Inc. is the first industrial producer of CoQ10(1974). CoQ10 can be produced by fermentation and chemical synthesis. In several companies, these two methods are used for the production of CoQ10:chemical synthesis - Yungjin, Daewoong, Nishin Parma; fermentation - Kaneka, Kyowa, Yungjin, etc. Researchs in microbial production of CoQ10 have several steps: screening of producing microorganisms, strain development, fermentation process, purification process, scale-up process, plant production. Several strategies are available for the strain development : Random mutation and screening, directed metabolic engineering. For the optimization of fermentation process, various conditions (nutrient, aeration, temperature, culture type, etc.) are considered. Purification is one of the most important step because the quality of final products entirely depends on its purity. The production cost will be reduced and the quality of the CoQ10 will be impoved by continuous researches in strain development, fermentation process, purification process.

• 한국환경과학회지
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• 제21권10호
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• pp.1255-1263
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• 2012

Batch cultivations were performed to evaluate the influences of the initial pH condition on mesophilic and thermophilic acidogenic fermentation with food waste recycling wastewater. In both conditions of mesophilic and thermophilic fermentation, TVFAs production rates were maximized at the initial pH 7 condition as 0.15 and 0.23 g TVFAs/L hr, respectively. And pH was also maintained stably between 6 and 7 during 72hr acidogenic cultivation at both conditions. However, predominant VFA components were different according to reaction temperature conditions. In mesophilic condition, propionic acid which has low conversion efficiency to methane was accumulated up to 1,348 mg/L while acetic and butyric acid were predominant in thermophilic condition. Therefore, thermophilic acidogenic fermentation was superior for the effective VFAs production than mesophilic condition. From the DGGE analysis, the band patterns were different according to the initial pH conditions but the correlations of the each band were increased in similar pH conditions. These results mean that microbial communities were certainly affected by the initial pH condition. Consequently, the adjustment of the initial pH to neutral region and thermophilic operation are needed to enhance acidogenic fermentation of food waste recycling wastewater.

• 한국약용작물학회지
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• 제20권6호
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• pp.472-478
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• 2012

This study was carried out to investigate solid-state fermentation method using cellulolytic lactic acid bacteria Lactobacillus plantarum TO-2100 in order to increase piperidine alkaloid contents in mulberry leaves. Piperidine alkaloid, one type of which include 1-deoxynojirimycin (1-DNJ), is known to inhibit ${\alpha}$-glycosidase activities. Using this strain, the optimal solid-state fermentation conditions on mulberry leaves powder were found as the following: initial moisture content, temperature and relative humidity were 20%, $30{\sim}35^{\circ}C$ and 60 ~ 70%, respectively, and the fermentation time was 72 hrs. The piperidine alkaloid contents in the fermented mulberry leaves were 2.86% on dry powder, which is 7-fold increase from that of non-fermented mulberry leaves. The 1-deoxynojirimycin contents after applying preparative thin layer chromatography were 2.02% on dry powder, which is 8 times higher than that of non-fermented mulberry leaves. ${\alpha}$-Glycosidase activities was inhibited by 65.7 ~ 84.7% with 3 ~ 5% treatments of hot-water extracts of the fermented mulberry leaves, compared to 16.2 ~ 40.2% with 3 ~ 5% treatments of hot-water extracts of non-fermented mulberry leaves. Therefore, the results suggest that solid-state fermentation method does indeed increase of piperidine alkaloid contents on mulberry leaves.

• Food Science and Biotechnology
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• 제15권4호
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• pp.564-571
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• 2006

In order to improve the quality and preservation of nabakkimchi, omija was added as an ingredient to determine its effect on the physicochemical characteristics of kimchi during fermentation, as well as the optimum level of omija extract. Omija extract was prepared from omija seeds by extraction with water for 9 hr at room temperature in concentrations (w/v) of 0.5, 1.0, 1.5, and 2.0% for use as an ingredient in nabakkimchi. The physicochemical characteristics of nabakkimchi containing omija extract were analyzed during fermentation of the product for up to 25 days. Delayed fermentation was observed, particularly in the early stage of fermentation, and was dependent on the concentration of the omija extract, as shown by stabilization of pH decreases and increases in the total acidity. An increased concentration of omija extract also raised the initial total vitamin C content and the reducing sugar content, which both then stabilized thereafter. Delayed development of turbidity within the optimum fermentation period of 16 days, increased redness and total color difference, and an electron-donor effect were also promoted by the omija extract. However, the omija extract also triggered extra tannin production, which leads to an astringent taste, especially at the 1.5 and 2.0% treatment levels.

• Mycobiology
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• 제51권3호
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• pp.157-163
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• 2023

Cordyceps fumosorosea is an important species in the genus of Cordyceps, containing a variety of bioactive compounds, including fumosorinone (FU). This study was a ground-breaking assessment of FU levels in liquid and solid cultures. The present study focused on the impacts of solid-state fermentation (SSF) using solid substrates (wheat, oat, and rice), as well as the effects of fermentation parameters (pH, temperature, and incubation period), on the generation of FU. All the fermentation parameters had significant effects on the synthesis of FU. In a study of 25 ℃, 5.5 pH, and 21 days of incubation period combinations calculated -to give maximal FU production, it was found that the optimal values were 25 ℃, 5.5 pH, and 21 days, respectively. In a solid substrate medium culture, FU could be produced from SSF. At 30 days, a medium composed of rice yielded the most FU (798.50 mg/L), followed by a medium composed of wheat and oats (640.50 and 450.50 mg/L), respectively. An efficient method for increasing FU production on a large scale could be found in this approach. The results of this study might have multiple applications in different industrial fermentation processes.

• Journal of Microbiology and Biotechnology
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• 제9권4호
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• pp.443-449
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• 1999

Bacillus subtilis BK-17 which produces a novel protease with fibrinolytic activity was isolated from soybean paste. Bioreactor production of the enzyme was studied in order to optimize fermentation conditions such as medium concentration, pH, agitation speed, and temperature. Under most cultural conditions, enzyme production initially began when the cell growth stopped. The onset of the enzyme production was indicated by rapid increase in both dissolved oxygen (DO) and pH. Two- to three-times more concentrated medium than the flask optimum medium yielded higher enzyme production in the bioreactor fermentation. When the medium pH was controlled constant, pH 6.5 exhibited the highest activity in the range of 6.0 to 7.5, but the activity was similar to the case when the pH was initially adjusted to 7.5 and subsequently maintained within a relatively wide range of 6.4 to 7.8. Agitation speed did not affect the enzyme production with an exception of DO reaching zero. Fermentation time was reduced when temperature increased within the range of $25^{\circ}C$ to$37^{\circ}C$. However, the highest activity, along with the slow decrease of the enzymatic activity after reaching the maximum value, was observed at $25^{\circ}C$. By shifting the temperature from $37^{\circ}C$ to $25^{\circ}C$immediately after DO reached the minimum level, the high enzyme production of 1,100 U/ml along with the short fermentation period of 13 h could be obtained.

• 생물환경조절학회지
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• 제16권3호
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• pp.174-179
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• 2007

참외 발효과 발생에 영향을 미치는 증산과 관련된 몇 가지 요인을 검토한 결과는 다음과 같다. 참외의 증산율은 지온이 높고 토양수분 함량이 많을수록 높았으며, 광도가 약하여 온도가 낮을 경우 증산율과 기공 전도도가 낮아졌고, 저온 다습한 기상조건에 의한 증산의 억제는 식물체와 대기사이의 증기압기울기가 낮아지는 것으로 생각된다. 발효과 발생은 과실의 비대가 느린 착색기 이후에 토양수분이 -10 kPa로 많고, 저온 다습하여 참외와 대기 사이에 증기압기울기가 낮게 형성되어 증산이 억제될 때 발생하였다. 따라서 참외의 발효과 발생은 착색기 이후 참외의 과실 비대가 지연되는 반면 지온이 높아 뿌리로부터 지상부로 수분의 공급이 원활하고, 저온 다습한 기상조건하에 수분의 증산이 억제되어 수분이 태좌부로 유입되면 발효과가 발생되는 것으로 생각된다.