• Asian-Australasian Journal of Animal Sciences
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• v.4 no.2
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• pp.137-141
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• 1991

Rumen liquor characteristics and disappearance rate of dry matter were studied in Kedah-Kelantan cattle and swamp buffaloes fed grass of rice straw-based diet. Cobalt-EDTA and chromium mordented fibres prepared from the faecal material were used to determine the liquid and solid particles movement in both animal species fed with rice straw. Swamp buffaloes showed a more intense rumen fermentation activity than Kedah-Kelantan cattle when both species were fed straw-based diet. The buffaloes also demonstrated faster rates of grass and straw degradation in situ. The fluid outflow rate from the rumen of buffalo ($1.06{\pm}0.19l/h$) was observed to be slower than that of cattle ($1.55{\pm}0.01l/h$). No significant differences between cattle and buffaloes were observed in rumen fluid volume and passage rate of small particles from the rumen.

• Journal of Korean Society on Water Environment
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• v.22 no.6
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• pp.1130-1136
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• 2006

This work elucidates the effects of pretreatment of the sewage sludge from wastewater treatment plant by microwave irradiation on elutriated acid fermentation. These experiments typically fell into two process; pretreatment as microwave irradiation and elutriated acid fermentation for hydrolysis and acidification as main process of primary sludge. The results of maximum solubilization rate of B, D primary and secondary sludge were 0.042, 0.086 and 0.15 gSCODprod./gICODin and the optimum irradiation time of microwave on 2,450 MHz and 900 W were 5 min. for primary sludge and 7 min. for secondary sludge. From batch tests on elutriated acid fermentation that was used the pretreated primary sludge as microwave, the optimum pH and HRT (hydraulic retention time) were 7 and 5 days at $35^{\circ}C$ condition.

• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.297-302
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• 1999

Simultaneous saccharification and fermentation (SSF) experiments were carried out with a lignocellulosic biomass. The effects of temperature on enzymatic saccharification and the ethanol fermentation were also investigated. The batch SSF process gave a final ethanol concentration of 10.44 g/l and equivalent glucose yield of 0.55 g/g, which was increased by 67％ or higher over the saccharification at 42℃. The optimal operating condition was found to vary in several parameters, such as the transmembrane pressure, permeation rate, and separation coefficient, related to the SSF combined with membrane system (semi-batch system). When the fermentation was operated in a semi-batch mode, the efficiency of the enzymes and yeast lasted three times longer than in a batch mode.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.4
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• pp.363-368
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• 2010

The overall indicator of microbial activity in the fermentation-extinction reaction of food waste by using bio wood-chips were investigated by considering adenosine tri-phosphate(ATP). Degradation rate of organic compounds, which was represented by chemical oxygen demand(COD) and total nitrogen(TN), was increased with the concentration of adenosine tri-phosphate during fermentation-extinction reaction of food waste by using bio-wood chips. With this view, the ATP would be one of the overall evaluation indicator of organic degradation in the species of bio-wood chip for the fermentation-extinction of food waste.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.647-649
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• 2006

Mevinolin, a fungal metabolite, is a potent inhibitor of 3-hydroxy-methyl-3-glutaryl-coenzyme A (HMG-CoA) reductase, the rate-controlling enzyme in cholesterol biosynthesis. In this investigation, the optimum factors for mevinolin production by Monascus pilosus IFO 480 in soymeal fermentation were studied. The highest yield of mevinolin, 2.82 mg mevinolin per g dry weight, without citrinin (a toxic fungal secondary metabolite) was obtained after 21 days of fermentation at $30^{\circ}C$ at 65% moisture content, particle size 0.6-0.9 mm, and initial substrate pH of 6.0. Mevinolin was present in the fermentation substrate predominantly in the hydroxycarboxylate form (open lactone, 92.1-97.3%), which is currently being used as a hypocholesterolemic agent.

• Korean journal of food and cookery science
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• v.19 no.2
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• pp.188-194
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• 2003

This study was conducted to investigate the effect of beef bone extracts on the organoleptic quality and fermentation of Baeck Kimchi. For this study, the organoleptic characteristics of Baeck Kimchi, with addition beef bone extracts were tested, and the changes in the fermentation factors, such as pH, acidity, reducing sugar and total microbial count, were observed during fermentation at 10$^{\circ}C$ and 20$^{\circ}C$. Greater amounts of lipids and soluble nitrogen were extracted to increasing the boiling time for the preparation of the beef bone extracts. However, 1% of the mixed beef bone extracts, prepared by boiling for 5, 7 and 9 hours, was the most acceptable for the Baeck Kimchi fermentation, as assessed from the results of sensory consumer tests. The beef bone extracts enhanced the umami taste of the unfermented Baeck Kimchi. The carbonated taste, sourness and fresh flavor of the fermented Baeck Kimchi were also enhanced. The fermentation rate was increased by the addition of beef bone extracts to Baeck Kimchi.

• KSBB Journal
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• v.15 no.4
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• pp.380-387
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• 2000

An extractive fermentation process using pervaporation was studied in a 7 liter fermentor. Pervaporation was performed using a silicone membrane module and a low-acid-producing strain Clostridium acetobutylicu, B18 was used to produce butanol. In batch culture without pervaporation pH 5.5 and initial glucose concentration of 60 g/L resulted in the highest butanol productivity (0.216 g/L$.$h) with butanol yield of 0.261 Butanol flux through the membrane was best at 2.0 L/min-tubing of air flow rate In batch and fed-batch fermentation glucose consumption rate increased by 1.3 times with pervaporation.

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.554-561
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• 1999

A novel estimation method was investigated for determining the concentrations of residual biomass, poly-3-hydroxybutyrate (PHB), and main nutrients including carbon and nitrogen sources, phosphate, and mineral ions from the supplied amount of ammonia solution used for a pH-control solution and nitrogen source in a PHB fermentation. The estimation equations for a batch culture and a fed-batch culture were derived from the relationship between the growth rate of residual biomass and the feed rate of the pH-control solution, and then were applied to the batch culture and the fed-batch cultures of Alcaligenes latus. This method was successfully applied to estimate the concentrations of residual biomass, PHB, and nutrients.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2005.06a
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• pp.233-244
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• 2005

Guanosine fermentation process can be well predicted and analyzed by the proposed state equations describing the dynamic change of a bioreactor. Pyruvate and alanine were found to be characteristically accumulated along with the decline of the guanosine formation rate during the mid-late phase of the process. The enzymological study of the main pathways in glucose catabolism and the quantitative stoichiometric calculation of metabolic flux distribution revealed that it was entirely attributed to the shift of metabolic flux from hexose monophosphate (HMP) pathway to glycolysis pathway. The process optimization by focusing on the restore of the shift of metabolic flux was conducted and the overcoming the decrease of oxygen uptake rate (OUR) was taken as the relevant factor of the trans-scale operation. As a result, the production of guanosinewas increased from 17 g/L to over 34 g/I.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.789-793
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• 1999

The effect of acetic acid formation deficiency on recombinant E. coli fermentation was investigated using a mutant strain deficient in acetic acid formation. A mutant strain which does not grow under anaerobic conditions was isolated. The acetic acid production in this strain was negligible in aerobic batch fermentation. The cloned-gene expression in the mutant strain was higher than the wild-type strain. Fed-batch fermentations with controlled specific growth rates were carried out in order to compare the cloned-gene expression between the wild-type and the mutant strains. The expression decreased along with the specific growth rate in both strains. The cloned-gene expression in the mutant strain was 60% higher than in the wild-type strain at the same specific growth rate.