• Applied Biological Chemistry
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• v.30 no.4
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• pp.311-314
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• 1987

High-level yeast inocula was investigated as a means of overcoming the inhibition problem in ethanol fermentation of hemicellulose hydrolyzate. When the inoculum exceeded 25g dry cells/liter, the fermentation proceeded completely to the end within 24 hours. Furfural was taken up by Pachysolen tannophilus and catabolized to furfuryl alcohol. Thus inhibitory effect of furfural component was less adverse toward ethanol production than that of non-furfural components in hemicellulose hydrolyzate. The specific ethanol productivity in the fermentation of hemicellulose hydrolyzate was 14% of that of simulated media containing 41.8g xylose and 2.3g furfural per liter.

• Korean journal of food and cookery science
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• v.17 no.5
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• pp.503-509
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• 2001

The effects of salting methods on textural properties of Kakdugi were evaluated during fermentation at 1$0^{\circ}C$ for up to 52 days. Kakdugi samples were prepared by 4 different salting methods at final salt concentration of 1.5%, which is appropriate for organoleptic quality. The salting methods for radish cubes(2 cm size) of Kakdugi were as follows; 1) Treatment S-1: spraying dry salt uniformly on to the radish cubes at 1.5%(w/w) and holding for 1 hr, 2) Treatment S-5: spraying dry salt uniformly on to the radish cubes at 1.2%(w/w) and holding for 5 hr, 3) Treatment B-1: brining radish cubes in a 8.5%(w/v) salt solution for 1 hr, 4) Treatment B-5: brining radish cubes in a 4.0%(w/v) salt solution for 5 hr. The contents of water soluble pectin, total soluble solid and PG activity were increased as the fermentation periods increased. A majority of total dietary fiber(TDF) consisted of soluble dietary fiber(SDF), and the amount of insoluble dietary fiber(IDF) was relatively small in Kakdugi during fermentation. Furthermore, an increase in SDF and a consequent decrease in IDF contents were observed with the fermentation time increased.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1159-1163
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• 2005

The production of hydrogen by Chlamydomonas reinhardtii UTEX 90, a marine green alga, was performed under dark fermentation. The effects of initial nitrogen and phosphorus concentration on the cell growth and the production of hydrogen and organic substances were investigated. In the growth stage, the maximum dry cell weight (DCW) was 3 g/l when the initial ammonium concentration was 15 mM. In the dark fermentation, the maximum hydrogen production was $3.5\;{\mu}mol/\;mg$ DCW when the initial nitrogen concentration was 7.5 mM. The nitrogen concentration had a greater effect on organic compound and hydrogen production than the phosphorus concentration during the dark fermentation. An investigation of the duration of dark fermentation showed that, at least until three days, dark fermentation should be prolonged for maximum hydrogen production.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.1
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• pp.1-9
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• 2017

This research was conducted to investigate the effects of feeding high and low forage diets with different forage sources on rumen fermentation characteristics and blood parameters of Holstein cows during the dry period. Eight Holstein cows were completely randomized assigned to two groups and repeated measurement was utilized in the analysis. Cows in two treatments were fed with diets with high (F:C = 70:30, 70F; forage source: mixed-sowing whole crop barley and Italian ryegrass silage, BIRG) and low (F:C = 55:45, 55F; forage source: tall fescue hay, TF) forage level. Rumen fluid pH was higher in 70F group. Levels of acetic acid, propionic acid, and butyric acid showed a similar pattern: from the lowest value at 07:30 h to the highest at 10:30 h and then decreased in both groups. The ratio of acetic acid to propionic acid was significantly higher (p < 0.05) in 55F group at 09:30 and 10:30 h. Rumen fluid $NH_3-N$ concentrations were significantly higher (p < 0.05) in 70F group at 09:30 and 10:30 h. Blood urea nitrogen was significantly higher (p < 0.05) in 70F group. It was concluded that BIRG based diet with a high forage level had no adverse effects on rumen fermentation, some blood chemical parameters, and immune system in dry Holstein cows and could be used as a forage source instead of imported TF.

• KSBB Journal
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• v.23 no.6
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• pp.504-508
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• 2008

The objectives of this study were to develope the economical process for bioethanol production from domestic triticale and investigate optimal fermentation conditions such as temperature, time, and enzyme concentration used to pre-treatment process. Triticale mash, containing 148 g of total sugar per 1 L of mash, was fermented with Saccharomyces cerevisiae CHY1011 at $33^{\circ}C$. Fermentation of mash supplemented with enzyme was completed within 48-60 hours, and the ethanol yield was 410.9 L/tonne of dry base. On the other hand, fermentation of mash without enzyme addition was completed within 36-48 hours, but the ethanol yield was 342.2 L/tonne of dry base. For optimal bioethanol production from triticale, viscosity reduction enzyme was added in the pre-treatment process, and the fermentation rate of triticale was 92.0-94.2%. In addition, the results showed that bioethanol production of triticale by low-temperature pre-treatment would provide higher ethanol production efficiency and lower operating costs.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.3
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• pp.216-222
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• 2017

This study was conducted to examine the effect of corn (Zea mays L.) - soybean (Glycine max L.) silage prepared by intercropping method on the nutritive value of the silage, in vitro rumen fermentation characteristics, dry matter degradability, as well as milk yield and milk composition of dairy cows. In a couple of experiments intercropped corn-soybean silage (CSBS) was compared with corn silage (CS) and/or Italian ryegrass hay (IRG). Numerically, CSBS had higher crude protein, ether extract, and lactic acid contents compared to CS. In vitro rumen fermentation analysis demonstrated that up to a 24-h incubation period, both CS and CSBS showed higher total gas production, ammonia N concentration, and dry matter degradability compared to IRG (p<0.05). The investigation on animals was conducted in a commercial dairy farm located in Gyeongju, South Korea, employing 42 Holstein cows that were divided into 2 group treatments: CS and CSBS in a completely randomized design. Although no significant difference was observed in milk yield, animals fed on CSBS showed significantly higher milk protein (p<0.05) and milk fat content (p<0.01), compared to animals fed on CS. Taken together, our findings indicate that corn-soybean silage that is cultivated, harvested, and prepared through intercropping can improve the protein content of the silage, and can also enhance in vitro rumen fermentation, dry matter degradability, and performance of dairy cattle.

• Microbiology and Biotechnology Letters
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• v.7 no.2
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• pp.71-74
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• 1979

The growth characteristics of Methylomonas methanolica YUFE 101, isolated from sewage samples, have been studied. conclusions of the study were; (1) Optimum cultivation pH and temperature are 6.3 and 32.5$^{\circ}C$ respectively (2) The specific oxygen uptake rate was 332 $\mu$ι/mg-dry weight/hr. (3) The maximum specific growth rate was 0.19 h $r^{-1}$ and celluar yield was 0.43 g-dry cell/g-methanol in batch culture, (4) The maximum biomass productivity achieved was 0.21 g-dry cel1/ι/hr at a dillution rate of 0.1 h $r^{-1}$ during continuous cultivation. (5) The contents of crude protein and total nucleic acid in the dry cell were 73 ％ and 12 ％ respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.6
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• pp.575-580
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• 1997

Two experiments were carried out to evaluate the effects of cellulase and brewers' grains addition on improvement of the fermentation quality and the nutritive value of barley straw silages made from dried or fresh straw. In Exp. I : 1 kg dried barley straw + 2 kg wet brewers' grains + 0 (I-0), 2 (I-2), 4 (I-4), 6 (I-6), and 8 (I-8) g of cellulase. In Exp. II : 2 kg fresh barley straw + 2 kg wet brewers' grains + 0 (II-0), 2 (II-2), 4 (II-4), 6 (II-6), and 8 (II-8) g of cellulase. Each prepared material was ensiled into vinyl bag silos (5 L capacity) and stored for 10 (Exp. I) or 7 (Exp. II) months at $21^{\circ}C$. The fermentation quality and nutritive value of barley straw silages produced were markedly improved by mixing them with wet brewers' grains, on the other hand the effect of cellulase addition on the fermentation and reduction of the cell wall components in the silos at ensiling more effectively occurred at low dry matter silages rather than at the high ones. All silages in both Exp. I and II were found well preserved as indicated by their low pH and high lactic acid concentration. Cellulase treated silages had a lower pH (p<0.05) and a higher lactic acid concentration (p<0.05) than those of without cellulase addition. NDF, ADF, and (Hemi)cellulose contents of cellulase treated silages reduced (p<0.05) compare to those of the corresponding silage without cellulase. Increasing levels of cellulase addition caused an increase in fermentation quality and reduction of cell wall components. In vitro dry mater digestibility was found similar in all silages. Fermentation quality and nutritive value of barley straw silages were improved by both wet brewers' grains and cellulase addition. Cellulase addition reduced the cell wall components silages, but did not improve the digestibility.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.6
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• pp.941-948
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• 2020

Objective: This study was carried out to determine the effects of elevated dietary cation and anion difference (DCAD) on dry matter intake (DMI) and ruminal fermentation pattern in lactating dairy goats under tropical conditions. Methods: Ten dairy goats were divided into two groups of five animals each. The groups received diets at different DCAD levels, either a control diet (22.81 mEq/100 g dry matter [DM], DCAD-23) or a DCAD-39 diet (39.08 mEq/100 g DM, DCAD-39). After parturition, DMI and water intake were recorded daily. Ruminal fluid and urine were collected, and nutrient digestibility measurements were carried out at 8th weeks postpartum (PP-8). Blood samples were collected at PP-4 and PP-8 to measure plasma leptin. Results: Dry matter intake/body weight (DMI/BW) at PP-8 of the animals fed the DCAD-39 diet was significantly higher than those fed with DCAD-23 diet (p<0.05). Animals fed with DCAD-39 consumed more water than those fed DCAD-23 over 24 h, particularly at night (p<0.05). Ruminal pH, acetate concentration, and urinary allantoin excretion increased with the DCAD-39 diet, whereas ruminal butyrate concentration was lower with the DCAD-39 diet. On the other hand, other ruminal parameters, such as total volatile fatty acid concentration, propionate molar proportion and acetate/propionate average ratio, were not affected by increased DCAD supplementation. Apparent digestibility was improved by increased DCAD supplementation. Plasma leptin concentration was higher with DCAD supplementation. Conclusion: When feeding goats with DCAD-39 under tropical conditions, an increase in DMI was associated with improved apparent digestibility of nutrients, ruminal fermentation and microbial protein synthesis. An increase in plasma leptin concentration could not explain the effect of high DCAD on DMI.

• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1053-1056
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• 2011

Optimal conditions for a high cell density fermentation were investigated in a recombinant Escherichia coli producing salmosin, a platelet aggregation inhibitor. The optimized carbon and nitrogen sources were glycerol 10 g/l, yeast extract 30 g/l, and bacto-tryptone 10 g/l, yielding the dry cell weight (DCW) of 10.61 g/l in a 500 ml flask culture. The late-stage induction with 1% L-arabinose in a 5 l jar fermentor showed the highest DCW of 65.70 g/l after 27 h of the fed-batch fermentation. Around 2,200 mg/l of the protein was expressed as an inclusion body that was then refolded to obtain the active salmosin of 96 mg/l. We also confirmed the inhibitory activity against platelet aggregation of the active salmosin from the high cell density fermentation.