• Asian-Australasian Journal of Animal Sciences
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• v.22 no.5
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• pp.651-658
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• 2009

Four multiparous lactating Holstein cows fitted with rumen cannulae were fed diets varying in the amount and source of rumen-degradable carbohydrates (starch vs. sucrose) to examine their effects on rumen fermentation, nitrogen metabolism and lactation performance. A $4{\times}4$ Latin square with four diets and four periods of 28 days each was employed. Corn starch and sucrose were added to diets and corn starch was replaced with sucrose at 0 (0 S), 2.5 (2.5 S), 5.0 (5.0 S) 7.5% (7.5 S) of diet dry matter in a total mixed ration (TMR) containing 60% concentrate and 40% forage (DM basis). Replacing corn starch with sucrose did not affect (p>0.05) ruminal pH which averaged 6.41, but the ruminal pH for 7.5 S decreased more rapidly at 2 h after morning feeding compared with other treatments. Sucrose reduced ($p{\leq}0.05$) ruminal $NH_3-N$ concentration (13.90 vs. 17.09 mg/dl) but did not affect peptide-N concentration. There was no dietary effect on total volatile fatty acids (110.53 mmol/L) or the acetate to propionate ratio (2.72). No differences (p>0.05) in molar proportion of most of the individual VFA were found among diets, except for the molar proportion of butyrate that was increased ($p{\leq}0.05$) with the inclusion of sucrose. Total branched chain volatile fatty acids tended to increase ($p{\geq}0.051$) for the control treatment (0 S) compared with the 7.5 S treatment. Dry matter intake, body weight changes and digestibility of DM, OM, CP, NDF and ADF were not affected by treatments. Sucrose inclusion in the total mixed ration did not affect milk yield, but increased milk fat and total solid percentage ($p{\leq}0.05$). Sucrose tended ($p{\geq}0.063$) to increase milk protein percentage (3.28 vs. 3.05) and reduced ($p{\leq}0.05$) milk urea nitrogen concentration (12.75 vs. 15.48 mg/dl), suggesting a more efficient utilization of the rapidly available nitrogen components in the diet and hence improving nitrogen metabolism in the rumen.

• Mycobiology
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• v.39 no.1
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• pp.33-39
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• 2011

Wild yeasts on the surface of various fruits including grapes were surveyed to obtain yeast strains suitable for fermenting a novel wine with higher alcohol content and supplemented with rice starch. We considered selected characteristics, such as tolerance to alcohol and osmotic pressure, capability of utilizing maltose, and starch hydrolysis. Among 637 putative yeast isolates, 115 strains exhibiting better growth in yeast-peptone-dextrose broth containing 30% dextrose, 7% alcohol, or 2% maltose were selected, as well as five ${\alpha}$-amylase producers. Nucleotide sequence analysis of the 26S rDNA gene classified the strains into 13 species belonging to five genera; Pichia anomala was the most prevalent (41.7%), followed by Wickerhamomyces anomalus (19.2%), P. guilliermondii (15%), Candida spp. (5.8%), Kodamaea ohmeri (2.5%), and Metschnikowia spp. (2.5%). All of the ${\alpha}$-amylase producers were Aureobasidium pullulans. Only one isolate (NK28) was identified as Saccharomyces cerevisiae. NK28 had all of the desired properties for the purpose of this study, except ${\alpha}$-amylase production, and fermented alcohol better than commercial wine yeasts.

• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.188-196
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• 2014

Extracellular production of recombinant human bone morphogenetic protein-7 (rhBMP-7) was carried out through the fermentation of Bacillus subtilis. Three significant fermentation conditions and medium components were selected and optimized to enhance the rhBMP-7 production by using the response surface methodology (RSM). The optimum values of the three variables for the maximum extracellular production of rhBMP-7 were found to be 2.93 g/l starch, 5.18 g/l lactose, and a fermentation time of 34.57 h. The statistical optimization model was validated with a few fermentations of B. subtilis in shake flasks under optimized and unoptimized conditions. A 3-L jar fermenter using the shake-flask optimized conditions resulted in a higher production (413 pg/ml of culture medium) of rhBMP-7 than in a shake flask (289.1 pg/ml), which could be attributed to the pH being controlled at 6.0 and constant agitation of 400 rpm with aeration of 1 vvm.

• Microbiology and Biotechnology Letters
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• v.25 no.2
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• pp.203-206
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• 1997

Takju is a traditional alcoholic beverage that has been prepared by fermenting the cooked rice and Nuruk (Korean-style bran koji). During fermentation. bacterial contamination is a problem which inhibits the growth of yeast and thus lowers the ethanol production from starch of rice, and causes souring. Major contaminants were known to be gram-positive acid producers at the early stage of fermentation. This problem would be solved if the contaminated bacteria could be controlled. Nisin, a GRAS-grade preservative, was added at the level of 500 iu/g as it retards the growth of the gram-positive bacteria. It was possible to control acid and ethanol production during fermentation. This process increased the ethanol production by 2 % comparing with control.

• Korean Journal of Microbiology
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• v.17 no.3
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• pp.152-159
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• 1979

Using Micromonospora strain, gentamicin was produced by fermentation. The increase in gentamicin productivity was studied by strain improvement and systematic optimization of fermentation process variables. The productivity of parent strain of M.purpurea (ATCC15835) was improved by selection of superior mutant after U.V. irradiation and induction of genetamicin resistance. Potato starch and soy bean meal were the best carbon and nitrogen sources for gentamicin fermentation, respectively. The optimum stimulating concentration of Co ion for gentamicin production was 0.006g $CoCl_2$ per liter of broth. Oxygen ws found to be an important factor for gentamicin yield. The optimum pH for the cell growth and gentamicin production were 7.2 and 6.8 respectively. By controlling the pH, oxygen, and other conditions found in this study at the optimal conditions for cell growth and gentamicin production, the total productivity of gentamicin was increased significantly.

• Food Science and Preservation
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• v.7 no.1
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• pp.94-98
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• 2000

To produce liquor and vinegar using potatoes needs to liquefy and sacchrify potatoes . So selecting the efficient fermenter for proceeding these process successfully is very important . This study was investigated several fermenter and crush types of potatoes for alcohol fermentation. Final sugar contents was high in pottoes saccharificatiion by nuruk or crude enzyme. But pure enzyme and blucoamylase ended liquefaction and saccharificatiion within short ime. So complex type fermenter mixed several fermenters was superior to single type fermenter. Complexfermenter III using crude enzyme and glucoamyulase saccharificed excellently potatoes with 150% of water contents by treatment of 3 hours. Through alcohol fermentation using pressure steamed potatoes (PSP), it could be obtained 6.4% , 150%, of alcohol content and yield. However to perform a series process efficiently , crush steamed pottoes (CSP) was suitable. When it was fermented after saccharification using crush steamed potatoes and complex fermenter III, it could be obtained 6.6% of alcohol and 6.7% of acidity.

• KSBB Journal
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• v.30 no.3
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• pp.125-131
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• 2015

Kluyveromyces marxianus is a well-known thermotolerant yeast. Although Saccharomyces cerevisiae is the most commonly used yeast species for ethanol production, the thermotolerant K. marxianus is more suitable for simultaneous saccharification and fermentation (SSF) processes. This is because enzymatic saccharification usually requires a higher temperature than that needed for the optimum growth of S. cerevisiae. In this study, we compared the fermentation patterns of S. cerevisiae and K. marxianus under various temperatures of fermentation. The results show that at a fermentation temperature of $45^{\circ}C$, K. marxianus exhibited more than two fold higher growth rate and ethanol production rate in comparison to S. cerevisiae. For SSF using starch or corn stover as the sole carbon source by K. marxianus, the high temperature ($45^{\circ}C$) fermentations showed higher enzymatic activities and ethanol production compared to SSF at $30^{\circ}C$. These results demonstrate the potential of the thermotolerant yeast K. marxianus for SSF in the industrial production of biofuels.

• Korean journal of food and cookery science
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• v.27 no.5
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• pp.577-587
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• 2011

In this study, lotus leaf was added to a Takju (Korean milky rice wine) preparation to evaluate its effects on physicochemical and fermentation properties. For rapid saccharification Takju was stored at 25$^{\circ}C$ for 2 days and then temperature was switched to 18$^{\circ}C$ to mature the wine for 21 days. From the start of fermentation to 2-days, the pH of Takju decreased rapidly and acidity increased. Maltose, a byproduct of starch saccharification, increased for 2 days then rapidly decreased. Glucose fluctuated for 7 days and of the 21-days fermentation. The ethanol production rate was highest during the first 7 days, then slowed. Total viable yeast and lactic acid bacterial counts increased rapidly for 2 days and then decreased gradually thereafter. Leuconostoc spp. grew rapidly for 1 day and sharply disappeared with decreasing pH. DPPH radical scavenging activity was significantly higher for Takju prepared with lotus leaf than without. The overall acceptance of Takju tended to increase when it was prepared with lotus leaf.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.381-387
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• 2003

This study was performed to establish the fermentation method of non-steamed brown rice vinegar using starch saccharifing enzyme. During vinegar fermentation, initial pH had increased in the higher concentration of alcohol and acetic acid. Final pH was gradually changed to pH 2.90~3.44 from 3.44~4.06. The higher total acidity of brown rice vinegar resulted from the higher alcohol concentration. The total acidity was slightly dropped after gradually increasing from the starting of fermentation. Initial pH was decreased from 3.67 to 3.16. The total acidity was gradually increased from the first day of fermentation with 1.02, it was 1.54 on the second day after fermentation and there was a tendency to decreased after the highest values with 6.53 fermentation for 12 days. In organic acid composition, oxalic, malic, acetic, citric, and succinic acid were detected. The total free amino acid was decreased to 1,121 mg%. The major amino acids were ${\gamma}$ -aminobutyric acid, $\alpha$-aminoadipic acid and alanine, and ${\gamma}$-aminobutyric acid was the highest (539 mg%). The mineral contents such as P and K was high in sample and followed by Mg, Na, Ca.

• The Korean Journal of Mycology
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• v.42 no.4
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• pp.328-332
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• 2014

For mass production of entomopathogenic fungus Beauveria bassiana 149, isolated from moth larva, by two-phase fermentation, we performed selection of carbon and nitrogen sources for liquid culture and examined solid fermentation on carrier, ingredient, temperature, and water content. Spore production with rice powder, corn powder, and starch from sweet potato was higher than that of sucrose and dissolvable starch for liquid fermentation as first-phase fermentation. As a nitrogen source, addition of peptone and yeast powder showed higher spore production than $NaNO_3$, fish powder, and soybean powder. The isolate produced more conidia in sawdust + wheat bran + corn powder, sawdust + wheat bran and rice shell + wheat bran as carrier and ingredient than vermiculite as carrier. Conidia production of B. bassiana 149 in solid-phase fermentation was twice higher at 30 than 20. Conidia yield was higher at 60% and 70% water content ($26.9{\times}10^8$ and $38.6{\times}10^8conidia/g$) than 40% and 50% ($13.9{times}10^8 $and $11.6{\times}10^8conidia/g$), respectively.