• Korean Chemical Engineering Research
• /
• v.51 no.2
• /
• pp.226-232
• /
• 2013

To produce biobutanol, fermentation processes using clostridia that mainly produce acetone, butanol and ethanol are used. In this work, a dynamic model describing the metabolic reactions in an acetone-butanol-ethanol (ABE)-producing clostridium, Clostridium acetobutylicum ATCC824, was proposed. To estimate the 58 kinetic parameters of the metabolic network model with experimental data obtained from a batch fermentor, we used an efficient optimization method combining a genetic algorithm and the Levenberg-Marquardt method because of the complexity of the metabolism of the clostridium. For the verification of the determined parameters, the developed metabolic model was evaluated by experiments where genetically modified clostridium was used and the initial concentration of glucose was changed. Consequently, we found that the developed kinetic model for the metabolic network was considered to describe the dynamic metabolic state of the clostridium sufficiently. Thus, this dynamic model for the metabolic reactions will contribute to designing the clostridium as well as the fermentor for higher productivity.

• Journal of Animal Science and Technology
• /
• v.45 no.4
• /
• pp.607-616
• /
• 2003

This study was conducted to determine the effect of feeding a total mixed ration(TMR) of broiler litter(BL) and bakery by-product(BB) with additional BL or rice straw incorporated at 10% of dietary DM as a roughage source on behavior pattern, nutrient intake, digestibility, digestible nutrient intake, ruminal and blood parameters, and N balance of sheep. All the treatment diets were formulated to be isoenergetic[total digestible nutrients(TDN) 66.9%]. Compared with the conventional formulated feed - rice straw feeding system(control), feeding TMR with BL(T1) or rice straw(T2) at 10% of dietary DM resulted in reduced eating, ruminating and total chewing time(P<0.05), similar DM intake, low(P<0.05) digestible DM, OM, fiber and total nutrients intake, low(P<0.05) nutrients digestibilities except EE, similar ruminal characteristics(pH, VFA concentrations and ratios, efficiency of carbohydrate fermentation, NH3-N), and favorable N digestion and retention. There were no differences in the above parameters between T1 and T2 with the exception of increased(P<0.05) eating, ruminating and total chewing time for T2. These results suggested that a TMR of BL and BB with or without rice straw may replace the conventional formulated feed and rice straw in ruminant diets successfully and furthermore feeding the TMR with rice straw made sheep behavior pattern more favorable.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.30 no.4
• /
• pp.343-354
• /
• 2010

The present study was conducted to examine the fermentation characteristics and effective degradability (ED) in the rumen, and whole tract digestibility of whole crop silage based TMR in comparison with conventional separate feeding of concentrate and roughage. Three ruminally fistulated non-lactating Holstein cattle were used in a 3 $\times$ 3 Latin square design. The cattle were fed 8kg of whole crop barley silage based TMR (BS-TMR) or 8kg (DM basis) of whole crop rye silage based TMR (RS-TMR) twice (08:00 and 18:00) daily in an equal amount. The cattle were also fed concentrate (5.6kg) and rice straw (1.4kg) seperately (DM basis, Control) twice daily in an equal amount. The both silages were included in TMR at 20% level (as fed basis). pH in the rumen fluid was not influenced by the diets but was slightly higher from TMR than from control. No difference was found in ammonia-N concentration between diets. Total VFA concentration was relatively increased in the cattle fed RS-TMR to the other diets up to 6h post feeding. The proportion of acetate was increased in the TMR feeding at right before feeding (0 h, p<0.005) and 9 h (p<0.048) post feeding compared with control. Propionate proportion was increased (p<0.046) in both TMRs while butyrate proportion was increased (p<0.029) at 1h post feeding compared to other diets. Effective degradability (ED) of DM and CP of RS-TMR was relatively increased to other diets, and EDNDF of both TMRs was higher than that of control diet due to the increased parameters b (p<0.039) and c (p<0.006) in TMR treatments. Whole track digestibility of most components in the TMRs was slightly increased compared to that in control diet, and RS-TMR had a tendency to be increased whole track digestibility except for NDF compared to BS-TMR. Based on the results observed from the present study, nutrient availability of whole crop silage based TMR looked slightly better than conventional separate feeding of concentrate and rice straw, mainly due to the improved stabilization of fermentation in the rumen and increased NDF digestibility of whole crop silage in TMR.

• Journal of Animal Science and Technology
• /
• v.50 no.2
• /
• pp.199-208
• /
• 2008

This study was undertaken to investigate the effects of ruminally protected amino acids (Methionine and Lysine) on in vitro ruminal parameters, and in vivo milk yield and milk composition in mid-lactating cows. In the first in vitro experiment, there were no statistical significances between treatments in ruminal pH and dry matter digestibility during various incubation times. In the second in vivo experiment, milk yield decreased by 11.92% in control and 5.68% in the treatment respectively, but decrease rate of milk yield in the treatment was lower than control. Milk yields naturally decreased as time goes by since the DIMs(Days in milk) of the cows in experiment were in mid-lactation period. 4% FCM(Fat corrected milk) and milk protein yields also, respectively, decreased by 11.25% and 11.09% in control and 6.16% and 5.47% in the treatment as compared with the intial. Milk protein and milk fat production were higher in the treatment(0.90kg, 1.10kg) than those of control(0.66kg, 0.79kg). Milk fat content significantly increased with supplementing protected amino acids as compared to control(P<0.05). From the above results, protected amino acids were positively utilized in the performances of mid-lactating cows without inhibiting rumen fermentation. Further investigation is suggested for essential amino acid composition and intestinal digestion rate out of rumen bypass protein in dietary protein to be estimated.

• Korean Journal of Agricultural Science
• /
• v.27 no.1
• /
• pp.25-32
• /
• 2000

This experiment was conducted to investigate the effect of feeding monensin on the growth performance and ruminal fermentation characteristics of Han-Woo cattle. Seventy two uncastrated Han-Woo male cattle(BW 267 kg) were randomly allotted to 0, 22, and 33 ppm monensin treatments, three replicates per treatment and eight heads per replicate. Animals were kept in an open barn for an 140-d feeding trial, Concentrates containing different levels of monensin and rice straw cut in 15cm length were fed ad libitum separately. The results obtained from this study were summarized as follows. 1. No significant difference was found in daily gain by monensin feeding. 2. Monensin did not affect the total feed (concentrate + roughage) intake: however, as the monensin level increased, the total feed intake tended to decrease, resulting in 5 % reduction in 33 ppm monensin treatment. 3. Although no significant difference was found among three treatments, 22 and 33 ppm monensin improved the feed efficiency(total feed/gain) by 5.2 % and 5.1 %, respectively, as compared to the 0 ppm monensin treatment. 4. Monensin did not affect the concentrations of ruminal total VFA and acetic acid consistently. Although not significant, monensin feeding of 22 and 33 ppm caused marked increase in ruminal propionic acid concentration, 13.8 % and 19.3 %, respectively. Ruminal butyric acid concentration decreased as monensin level increased. Monensin feeding, regardless of level, decreased the A/P ratio by 12.5 %. In conclusiuon, monensin feeding increased the propionic acid concentration, and decreased the butyric acid concentration and A/P ratio in the rumen. Animals fed monensin consumed less feed, causing the improvement in feed efficiency. Thus, monensin appeared to be a useful feed additive, directing the rumen fermentation in a more productive way. Feed efficiency improved similarly both in 22 and 33 ppm monensin treatments, indicating that 22 ppm might be good enough rather than the 33 ppm monensin level.

• Applied Biological Chemistry
• /
• v.39 no.3
• /
• pp.172-176
• /
• 1996

Effect of culture conditions such as pH, temperature, agitation speed and oxygen transfer rate on xylitol production from xylose by Candide parapsilosis ATCC 21019 mutant was investigated in a jar fermentor. The initial concentration of xylosr was fixed at 50 g/l in this experiment. When pH was increased, cell growth and xylose consumption rate were increased, but maximum xylitol production was shown in the range of pH 4.5 and 5.5 with a yield of 0.68 g/g-xylose. The optimal temperature for xylitol production was determined to be $30^{\circ}C$. Considering the importance of dissolved oxygen tension, for xylitol production, the effect of oxygen transfer rate coefficient $(k_La)$ on fermentation parameters was carefully evaluated in the range of $20{\sim}85\;hr{-1}\;of\;k_La$ (corresponding to $100{\sim}300$rpm of agitation speed). The xylitol production was maximized at $30\;hr^{-1}\;of\;k_La$(150 rpm). A higher oxygen transfer rate supported better cell growth with lower xylitol yield. It was determined that maximum xylitol concentration, xylitol yield and productivity was 35.8 g/l, 71.6% and $0.58\;g/l{\sim}hr^{-1}$, respectively, at $30\;hr^{-1}\;of\;k_La$ In order to further increase xylitol productivity, ferementation using the concentrated biomass(20 g/l) was carried out at the conditions of pH 4.5, $30^{\circ}C$ and $30\;hr\;1$ of oxygen transfer rate. The final xylitol concentration of 40 g/l was obtained at 18 hours of culture time. From this result, it was calculated that xylitol yield was 80ft on the basis of xylose consumption and volumetric productivity was $2.22\;g/l{\sim}hr$ which was increased by $3{\sim}4$ fold compared with $0.5{\sim}0.7\;g/l-hr$ obtained in a normal fermentation condition.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.42 no.2
• /
• pp.61-72
• /
• 2022

The present study was conducted to examine the effect of soybean silage as a crude protein supplement for corn silage in the diet of Hanwoo steers. The first experiment was conducted to evaluate the effect of replacing corn silage with soybean silage at different levels on rumen fermentation characteristics in vitro. Commercially-purchased corn silage was replaced with 0, 4, 8, or 12% of soybean silage. Half gram of the substrate was added to 50 mL of buffer and rumen fluid from Hanwoo cows, and then incubated at 39℃ for 0, 3, 6, 12, 24, and 48 h. At 24 h, the pH of the control (corn silage only) was lower (p<0.05) than that of soybean-supplemented silages, and the pH numerically increased along with increasing proportions of soybean silage. Other rumen parameters, including gas production, ammonia nitrogen, and total volatile fatty acids, were variable. However, they tended to increase with increasing proportions of soybean silage. In the second experiment, 60 Hanwoo steers were allocated to one of three dietary treatments, namely, CON (concentrate with Italian ryegrass), CS (concentrate with corn silage), CS4% (concentrate with corn silage and 4% of soybean silage). Animals were offered experimental diets for 110 days during the growing period and then finished with typified beef diets that were commercially available to evaluate the effect of soybean silage on animal performance and meat quality. With the soybean silage, the weight gain and feed efficiency of the animal were more significant than those of the other treatments during the growing period (p<0.05). However, the dietary treatments had little effect on meat quality except for meat color. In conclusion, corn silage mixed with soybean silage even at a lower level provided a greater ruminal environment and animal performances, particularly with increased carcass weight and feed efficiency during growing period.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.32 no.1
• /
• pp.59-74
• /
• 2012

Buffer solubility and protein fractionation were evaluated from the hays (timothy, alfalfa and klein) and straws (tall fescue and rice), and $In$ $vitro$ trial was conducted to examine the effect of buffer extraction on fermentation characteristics, degradability and gas ($CO_2$ and $CH_4$) production. Buffer soluble protein (SP) content and A fraction in total protein were highest in alfalfa hay as 61% and 41.77%, respectively while lowest in rice straw (42.8% and 19.78%, respectively). No difference was observed in B1 fraction among forages but B2 fraction was slightly increased in klein hay (12.34%) and tall fescue straw (10.05%) compared with other forages (6.34~8.85%). B3 fraction of tall fescue was highest as 38.49% without difference among other forages while C fraction was highest in rice straw. pH in incubation solution was higher in all forages after extraction than before extraction at 3h (P<0.01) and 6h (P<0.05), and pH from hays of timothy and alfalfa was higher than the other forages at 6h (P<0.05) and 12h (P<0.001). Regardless of extraction, ammonia-N concentration from alfalfa hay was increased at all incubation times and extraction effect was appeared only at 3h incubation time (P<0.01). Total VFA concentration from alfalfa hay was highest up to 24h incubation while those from tall fescue straw and rice straw were lowest. Buffer extraction decreased (P<0.01~P<0.001) the total VFA concentration. Acetic acid proportion was increased (P<0.001) before extraction of forages but no difference was found between forages. Propionic acid($C_3$) proportion was also increased(P<0.001) before extraction in all forages than in straws at 3h, 24h and 48h incubations, and $C_3$ from hays were mostly higher (P<0.05) than from straws. Butyric acid proportion, however, was not affected by extraction at most incubation times. Parameter 'a' regarding to the dry matter (DM) degradation was increase (P<0.001) in all forages before extraction, and was decreased (P<0.05) in tall fescue straw and rice straw compared with hays. Parameter 'b' was also increased (P<0.001) before extraction but no difference was found between forages. Effective degradability of DM (EDDM) was higher (P<0.001) before extraction in most forages except for rice straw. Buffer extraction decreased (P<0.05) all parameters (a, b, and c) regrading to the crude protein (CP) degradation but no difference was found between forages. Effective degradation of CP (EDCP) was lower (P<0.05) in straws than in hays. Parameters 'a' and 'b' regarding to the NDF degradation (P<0.01) and effective degradability of NDF (EDNDF, P<0.001) were also higher in forages before extraction than after extraction but no difference was found between forages. Buffer extraction reduced (P<0.05~P<0.001) $CO_2$ production from all the forages uo to 24h incubation and its production was greater (P<0.05~P<0.01) from hays than straws. Methane ($CH_4$) production was also greater (P<0.01~P<0.001) in all forages at all incubation times, and its production was greater (P<0.05) from hays than from straws at most incubation times. Based on the results of the current study, it can be concluded that buffer solubility and CP fractionation might be closely related with $In$ $vitro$ VFA concentration, degradability and gas ($CO_2$ and $CH_4$) production. Thus, measurement of buffer solubility and protein fractionation of forages might be useful to improve TMR availability in the ruminants.

• Journal of Life Science
• /
• v.25 no.8
• /
• pp.917-924
• /
• 2015

This study aimed to evaluate the protective effect of Orostachys malacophyllus (OM) and fermented O. malacophyllus (FOM) in Sprague-Dawley rats who had been intoxicated with 1% (w/w) orotic acid (OA) for 10 days. The activities of several hepatic enzymes, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and cholinesterase, were increased when OA was given, but these parameters were significantly decreased by FOM treatment. In addition, OA treatment resulted in an increased lipid peroxidative index (thiobarbituric acid-reactive substances, TBARS). A worsened antioxidant status (reduced glutathione) in the liver and serum was also observed. FOM treatment improved the antioxidant status of OA-induced fatty-liver rats, which was evaluated by decreased levels of the lipid peroxidative index and improved antioxidant status in the liver and serum. The contents of liver non-heme iron were increased with OA treatment and significantly decreased with FOM treatment, which suggested that the lipid peroxidation contents were inversely correlated with liver non-heme iron content. Based on these results, FOM is considered a material with significant potential for development into a functional health food that can improve fatty-liver conditions.

• Journal of Life Science
• /
• v.21 no.10
• /
• pp.1407-1414
• /
• 2011

This study is aimed to evaluate the protective effect of Cordycepin-enriched Cordyceps militaris (CM${\alpha}$) strain on orotic acid (OA)-induced fatty liver in rats. OA treatment induced the retardation of body weight gain and enlargement of the liver. The activities of liver marker enzymes, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), Alk. phosphatase and Cholinesterase were increased when treated with OA, but these parameters were significantly decreased in the CM${\alpha}$ group. The current study observed significant elevations of thiobarbituric acid-reactive substance (TBARS) levels. However, among the OA groups, the CM${\alpha}$ group showed significantly low TBARS levels of hepatic homogenate. The OA group resulted in a significant decrease in the levels of plasma and hepatic glutathione, but these reductions were significantly increased in the CM${\alpha}$ group. These effects were more pronounced in the CM${\alpha}$ group than in the PJ or CM groups in Orotic acid treated rats. Accordingly, Cordycepin-enriched Cordyceps militaris (CM${\alpha}$) may be an ideal candidate for hepatoprotective effects in animal models.