• 한국수산과학회지
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• 제29권6호
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• pp.882-887
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• 1996

Production of yeast diet has been carried out in batch fermenters under optimum culture conditions. The fermentation of Candida utilis on a $2\%$ complex medium resulted in 1.22 g/L/h productivity and $65\times10^8$ viable cells/ml, and the addition of $15{\mu}M$ zinc to the medium increased both the productivity and the number of viable cells just a little more. In the case of the fermentation of Kluyveromyces fragilis, the highest value of the biomass productivity, 1.94 g/L/h, was obtained on a $2.5\%$ fructose medium with $70\times10^8$ viable cells/ml, and $1\%$ peptone was found to be a growth factor in this fermentation. When $3.5\%$ NaCl was added to the given medium, both the biomass productivity and the number of viable cells decreased significantly in each fermentation, but this may be considered to preserve yeast diet long without osmotic lysis.

• Journal of Plant Biology
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• 제7권3호
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• pp.1-8
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• 1964

Exposing yeast cells with a certain genotype to different inducers, the ability of the yeast cells (Saccharomyces cerevisiae) to obtain enhanced fermentation for carbohydrates was observed. Regardless of the preexposure to any substrate, the inherent character incapable of fermenting a certain carbohydrate was maintained, while utilization of carbohydrates by the cells with a certain gene markers was varied by the previous conditions where they were exposed. Galactose was the best inducer for the cells to elaborate melibiase, even the galactose was not utilized as a substrate. Preexposure to galactose seemed to be necessary for the cells to utilize galactose and melibiose. Galactose fermentation by GA cells was enhanced by the exposure of the cells to galactose, but not to melibiose, raffinose, sucrose or glucose. Delayed fermentation of sucrose by the cells exposed to glucose or melibiose, but not to galactose, was observed. Raffinose fermentation was obtained by the cells with either SU RAF or GA ME genes, but the enhanced fermentation of raffinose seemed to be dependent on which inducer the cells were exposed previously and enzymes induced by the inducer to break either one of the linkages of raffinose molecule, the alpha0galactosidic or the beta-fructo-furanosidic.

• 식품과학과 산업
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• 제53권2호
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• pp.148-165
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• 2020

At beginning the fermentation is naturally occurred by natural microbes. Fermentation techniques apply as two ways, one is fermentation to produce fermented foods and the other is preservation of the foods for longer time for future. They contain various biological active ingredient, like as vitamins. Microorganisms concerning fermentation are well known the functionalities. Each nations in the world have unique and distinct foods and dietary habits on their own specific cultures and accessible edible raw resources of plant or animal origins. Many countries have their unique traditional fermented foods based on their natural conditions. Korea has very famous traditional fermented foods, as Kimchi, fermented soybean products(Jang), fermented fish products(Jeotgal) and vinegar. In this review will discuss the overall fermented foods and typical Korean traditional fermented foods with functionalities, and future effort to enlarge into wide range of new industry.

• Journal of Applied Biological Chemistry
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• 제57권3호
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• pp.197-203
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• 2014

Various parameters such as solvent selection, concentration, solid/liquid ratio, soaking time, temperature, stationary, shaking conditions, and repeated extractions were investigated in order to determine the optimum extraction conditions of ${\beta}$-glucosidase from bagasse fermented by mixed culture of Aspergillus niger NRC 7A and Aspergillus oryzae NRRL 447. Among various solvents tested, non ionic detergents gave the best results than the inorganic or organic salt solutions and distilled water. The optimum conditions for extraction of ${\beta}$-glucosidase were 30 min soaking time at $40^{\circ}C$ under shaking condition at 150 rpm, with solid/liquid ratio 1:15 (w/v), which yielded $2882.74{\pm}95.52U/g$ fermented culture (g fc) of enzyme activity. With repeated washes under the above optimum conditions, the results showed that enzyme extracted in the $1^{st}$ and $2^{nd}$ washes represents about 90% of the total activity.

• KSBB Journal
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• 제8권5호
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• pp.452-456
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• 1993

Pichia stipitis CBS 5776에 의한 xylose의 최적 알코올 발효조건에 대한 연구를 수행하였다. 최적 세포성장 및 최대 ethanol 생성은 초가 pH가 5.0인 100 g/l 의 xylose배지를 이용하여 $30^{\circ}C$에서 0.05VVM으로 통기하고 300rpm으로 교반하는 발효 조건에셔 얻을 수 있었다. 이러한 최적 발효조건 서의 최대 비성장속도와 최대 세포농도는 각각 $0.14hr^{-1}$와 $1.3\times109$ cells/ml이였다. 또한 최대 etha­n nol 농도는 72시간 발효시에 100 g/l 의 xylose 중 에셔 96%을 이용하여 40.2 g/l 을 얻었으며, 이때 의 단위부피당 ethanol 생산성은 0.56 g/l-hr이고 ethanol 수율은 0.42g-ethanol/g-xylose로서 이론수율의 82%였다.

• 한국잠사곤충학회지
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• 제40권1호
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• pp.78-85
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• 1998

Colorants were prepared by extraction of natural indigo which was harvested just in the blooming season(in the late of July). 100 g of fresh leaves soaking in 1 ιwater was kept at 3$0^{\circ}C$, 30 hours. A solution of 3g/l calcium hydroxide was added into it to precipitate dye substance and it was freezing-dried into powder form. The fermentation and dyeing conditions were investigated. The results obtained are summarized as follows; K/S value of dyed silk fabrics of fermentation conditions was higher at 95$^{\circ}C$ for 20 min. than at 4$0^{\circ}C$ for 20 hours. Furthermore, K/S value of dyed silk fabric was raised by the addition of 5g/l of glucose and 5g/l of NaOH. K/S value of dyed silk fabric was raised by the addition of 5g/l of glucose and 5g/l of NaOH. K/S value increased as extending of dyeing time when dyed till 2 hours at 3$0^{\circ}C$. K/S value decreased in order of 3$0^{\circ}C$, 4$0^{\circ}C$ and 5$0^{\circ}C$, at the various dyeing temperatures and dyeing concentrations, and colour fastness ranged from 4 to 5 grade in terms of washing, perspiration and light fastness.

• 한국미생물·생명공학회지
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• 제23권3호
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• pp.346-351
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• 1995

To produce ethanol from Jerusalem artichoke powder efficiently, Kluyveromyces marxianus F043 cells were encapsulated in 2% sodium alginate and were cultured in a countinuous reactor to investigate the fermentation properties. Immobilized K. marxianus F043 cells were activated for 48 hours in a fermentor for continuous ethanol production. The culture in a CSTR using a Jerusalem artichoke substrate treated with 2% cellulase showed a decrease in ethanol concentration and an increase in residual saccharide concentration with a increasing dilution rate. Optimum conditions for high ethanol productivity and low residual saccharide output were clarified to be given at a dilution rate of 0.2 h$^{-1}$ and a Jerusalem artichoke medium concentration of 75 g/l. Ethanol productivity of 3.1 g/l-h and saccharide utilization of 62.6% were obtained under the optimum condition. When the fermentation was performed for 3 weeks under these conditions, the effluent medium showed stable ethanol concentrations of 16.3 - 17.9 g/l and viable cells of 6.60-7.16 log cells/ml without contamination. Trace amounts of methyl, n-propyl, iso-butyl, isoamyl alcohols besides ethanol were detected.

• 동아시아식생활학회지
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• 제20권5호
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• pp.743-750
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• 2010

The influence of various fermenting conditions using Saccharomyces cerevisiae, alone (Control, Single) and in combination with mixed lactic acid-producing bacteria (Combined 1, Mixed, Combined 2), including Bifidobacterium longum, Enterococcus faecium, and Lactobacillus acidophilus on flour sourdough preparation was examined. For the Combined 2 method, starters were incubated separately for 15 h, combined, and then further incubated for 10 h. Fermentation using Combined 2 improved the growth of mixed lactic acid-producing bacteria, but inhibited that of S. cerevisiae. This was also reflected in the extent of the pH reduction in sourdough produced in the Combined 2 step by these organisms. Among biochemical activities, $CO_2$ production and titratable acidity were increased by Combined 2, although the viable yeast counts were decreased. Aroma compounds in sourdough markedly varied according to fermentation conditions.

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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• pp.19-24
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• 2004

ED method is employed to effectively remove the organic acid salts in actual PDO fermentation broth. The lower electrical potential is selected to avoid the serious membrane fouling so as to ensure a stable and durative desalination process. Under the selected operation conditions, about 90% of organic acids salts are removed from PDO fermentation broth successfully by ED process. To reduce the loss of PDO product due to the diffusion, the operation time should be considered carefully. And based on mass balance equation and irreversible thermodynamics approach, a mathematical model is developed to describe the desalination process of an aqueous solution containing neutral solute by ED method. While the influence of concentration polarization is reflected by decreasing the conductivity of membrane, the model is verified well to describe the ED processes under varied operation conditions. Through the model, ED process of actual PDO fermentation broth is simulated to get a suitable scope of initial concentration in concentrated compartment.

• Journal of Microbiology and Biotechnology
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• 제22권7호
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• pp.939-946
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• 2012

Antibiotic production with Streptomyces sindenensis MTCC 8122 was optimized under submerged fermentation conditions by artificial neural network (ANN) coupled with genetic algorithm (GA) and Nelder-Mead downhill simplex (NMDS). Feed forward back-propagation ANN was trained to establish the mathematical relationship among the medium components and length of incubation period for achieving maximum antibiotic yield. The optimization strategy involved growing the culture with varying concentrations of various medium components for different incubation periods. Under non-optimized condition, antibiotic production was found to be $95{\mu}g/ml$, which nearly doubled ($176{\mu}g/ml$) with the ANN-GA optimization. ANN-NMDS optimization was found to be more efficacious, and maximum antibiotic production ($197{\mu}g/ml$) was obtained by cultivating the cells with (g/l) fructose 2.7602, $MgSO_4$ 1.2369, $(NH_4)_2PO_4$ 0.2742, DL-threonine 3.069%, and soyabean meal 1.952%, for 9.8531 days of incubation, which was roughly 12% higher than the yield obtained by ANN coupled with GA under the same conditions.