• Journal of Animal Science and Technology
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• v.53 no.2
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• pp.155-160
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• 2011

Present experiment was carried out to determine maintenance energy requirements for growing Hanwoo steers. Six Hanwoo steers (BW = $180.6{\pm}3.1$ kg) were used in two 3 ${\times}$ 3 latin square design with three different energy intake levels; TDN 1.70 kg (Low), 2.05 kg (Medium), 2.80 kg (High), respectively, based on the Korean Feeding Standards. Each period lasted 18 days including a 14-day adaptation and a 4-day measuring period. The steers were in the head hood chamber system (one cattle per chamber) during each measuring time to measure heat and methane production for 1 day. Dry matter intake was 2,058, 3,256 and 3,881 g/day for Low, Medium and High TDN, respectively. Increase in energy intake did not affect digestibilities of dry matter, crude protein, crude fiber, crude fat, NDF, ADF and nitrogen-free extract. Gross energy intake averaged 180.21, 292.74 and 337.15 kcal/$BW^{0.75}$ for Low, Medium and High TDN, respectively. Energy loss was 28.7% in feces and 2.1% in urine of gross energy intake. Further, energy loss from methane produced during rumen fermentation was 6~8.3%, while body heat loss averaged 34~60%. Intercept of regression equation between ME intake and retained energy indicated that the energy requirement was 109.84 kcal ME/$BW^{0.75}$.

• Journal of Energy Engineering
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• v.23 no.3
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• pp.125-131
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• 2014

In order to increase landfill gas (LFG) production with food waste leachate, this study was confirmed to be acidogenetic conditions for landfill site injection. Thereby, it was conducted for acidogenetic treatments to determine the decrease in viscosity and VFA production. After acidogenesis treatments, solubility of food waste leachate increased approximately 15%, and as a result, UASB and CSTR were similar by reactor type using the change of retention time. Based on the result of the change in viscosity by reactor type, efficiency of UASB showed approximately 11.38% of higher decrease in viscosity as $76.95{\pm}3.27%$ vs. CSTR. Also, VFA production showed the higher increase of 2.01 times (UASB) and 1.76 times (CSTR) respectively at the point of increasing retention time from 3 to 5 days. From the above results, efficiency of UASB in a reactor was relatively higher because large molecular lead to longer retention time than small molecular due to having screen effect in the fixed media.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.1
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• pp.54-61
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• 2007

The influences of pH were investigated for anaerobic hydrogen gas production under the constant pH condition ranged from pH 3 to 10. Carbon dioxide and hydrogen gas were main components of the gas but methane was not detected in the produced gas when sucrose was added in enrichment medium. When the modified Gompartz equation was applied for the statistical analysis of experimental data, a hydrogen production potential and maximum gas production rate at pH 5 were 1,182 mL and 112.46 mL/g dry wt biomass/hr. The hydrogen conversion ratio was 22.56%. The butyrate/acetate ratios at pH 5 and pH 6 are 1.63 and 0.38. Higher butyrate/acetate ratio produced more hydrogen gas generation. The Haldane equation model was used to find the optimum pH and fitted well with the experimental data$(r^2=0.98)$. The optimum pH and specific hydrogen production were 5.5 and 119.61 mL/g VSS/h.

• KSBB Journal
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• v.23 no.1
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• pp.83-89
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• 2008

Food wastewater derived from the three-stage methane fermentation system developed in this lab contained high concentration organic substances. The organic wastewater should be treated through advanced wastewater treatment system to satisfy the "Permissible Pollutant Discharge Standard of Korea". In order to treat the organic wastewater efficiently, several optimum operation conditions of a modified $UV/TiO_{2}$ photocatalytic system have been investigated. In the first process, wastewater was pre-treated with $FeCl_{3}$. The optimum pH and coagulant concentration were 4.0 and 2000mg/L, respectively. Through this process, 52.6% of CODcr was removed. The second process was $UV-TiO_{2}$ photocatalytic reaction. The optimum operation conditions for the system were as follows: UV lamp wavelength, 254 nm; wastewater temperature, $40^{\circ}C$; pH 8.0; and air flow rate, 40L/min, respectively. Through the above two combined processes, 69.7% of T-N and 70.9% of CODcr contained in the wastewater were removed.

• Korean Journal of Microbiology
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• v.37 no.4
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• pp.317-324
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• 2001

We have previously developed three stage methane fermentation system capable of digesting food wastes effectively and then releasing high organic wastewater as a final product. In this study, we tried to devise an ecological water treatment system, which can efficiently remove the nitrogen and phosphorus contained in the organic wastewater. The system was made of microbiological filters, algae, and waterfleas. Of two species of alga tested, Selenastrum capricornutum showed higher growth rate and more efficiently removed the nitrogen from the wastewater than by Chlorella sp. In addition, the highest growth rate and the nitrogen removal efficiency could be obtained when high concentrations of $Mg^{2+}\; and\; Ca^{2+}$ were added to the diluted wastewater and the molar ratio of nitrogen to phosphorus was adjusted to 10 : 1. In this study the population relationship between alga and water flea was also examined in a test tube. The initial number of algal cells decreased as the waterflea population increased. However, the number of algal cells gradually increased again when waterflea population decreased partly due to the environmental resistance. From these results, it was believed that the ecological water treatment system could be used for removing the nitrogen and phosphorus from organic wastewater very effectively. Moreover, the waterflea cultured by this system as a final predator could be used as a good foodstuff for fishes.

• Journal of Life Science
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• v.17 no.11
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• pp.1555-1561
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• 2007

In order to know the effects of scoria, germanium, charcoal, ginger, stevia, and CLA(Conjugated Linoleic Acid) as biologically active materials on pathogenic microbes and rumen anaerobic microbes, the growth rate of pathogens (including Escherichia coli O157, Salmonella paratyphi, Listeria monocytogenes and Staphylococcus aureus) and in vitro lumen microbial growth, gas production, ammonia concentration, carboxymethyl-cellulase (CMCase) activity, and microbial populations were investigated. The growth of pathogenic microbes was inhibited by the supplement of 0.10% ginger. Ginger had powerful antimicrobial properties on all the pathogens used in this experiments. Additionally in the antibacterial assay by paper disc method, we could observe the clear zone of similar area with the positive control(antibiotics) for E. coli as applied with the 10% stevia or the 10% CLA only. The supplements of ginger, stevia and CLA in vitro rumen fermentation inhibited populations of rumen bacteria and protozoa. Particularly supplement of ginger resulted in remarkable reduction of the protozoa population, which means it might serve as a source inhibiting material of methane creation in the rumen.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.2
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• pp.129-140
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• 2014

This study was performed to evaluate the effects of replacing basic total mixed ration (TMR) with fermented soybean curd, Artemisia princeps Pampanini cv. Sajabal, and spent coffee grounds by-product on rumen microbial fermentation in vitro. Soybean in the basic TMR diet (control) was replaced by the following 9 treatments (3 replicates): maximum amounts of soybean curd (SC); fermented SC (FSC); 3, 5, and 10% FSC + fermented A. princeps Pampanini cv. Sajabal (1:1, DM basis, FSCS); and 3, 5, 10% FSC + fermented coffee meal (1:1, DM basis, FSCC) of soybean. FSC, FSCS, and FSCC were fermented using Lactobacillus acidophilus ATCC 496, Lactobacillus fermentum ATCC 1493, Lactobacillus plantarum KCTC 1048, and Lactobacillus casei IFO 3533. Replacing dairy cow TMR with FSC treatment led to a pH value of 6 after 8 h of incubation-the lowest value measured (p<0.05), and FSCS and FSCC treatments were higher than SC and FSC treatment after 6 h (p<0.05). Gas production was higher in response to 3% FSC and FSCC treatments than the control after 4-10 h. Dry matter digestibility was increased 0-12 h after FSC treatment (p<0.05) and was the highest after 24 h of 10% FSCS treatment. $NH_3-N$ concentration was the lowest after 24 h of FSC treatment (p<0.05). Microbial protein content increased in response to treatments that had been fermented by the Lactobacillus spp. compared to control and SC treatments (p<0.05). The total concentration of volatile fatty acids (VFAs) was increased after 6-12 h of FSC treatment (p<0.05), while the highest acetate proportion was observed 24 h after 5% and 10% FSCS treatments. The FSC of propionate proportion was increased for 0-10 h compared with among treatments (p<0.05). The highest acetate in the propionate ration was observed after 12 h of SC treatment and the lowest with FSCS 3% treatment after 24 h. Methane ($CH_4$) emulsion was lower with A. princeps Pampanini cv. Sajabal and spent coffee grounds treatments than with the control, SC, and FSC treatments. These experiments were designed to replace the by-products of dairy cow TMR with SC, FSC, FSCS, and FSCC to improve TMR quality. Condensed tannins contained in FSCS and FSCC treatments, which reduced $CH_4$ emulsion in vitro, decreased rumen microbial fermentation during the early incubation time. Therefore, future experiments are required to develop a rumen continuous culture system and an in vivo test to optimize the percentages of FSC, FSCS, and FSCC in the TMR diet of the dairy cows.

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

• Korean Journal of Environmental Agriculture
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• v.15 no.3
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• pp.362-371
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• 1996

This study was conducted to investigate the biochemical properties of isolated bacteria, low temperature tolerant methanogens which were selected for use as inoculum for anaerobic fermentation of agricultural and livestock wasted at low temperature. The results, obtained were summarized as follows: Low temperature tolerant methanogens were isolated from the samples which showed the high methanogenesis rate by enrichment culture at low temperature in methanol medium. These methanogens, Methanobacterium M-251 and Methanobacterium M-253 were isolated from swampy sediment at latitude $56.9^{\circ}$, Methanosarcina mazei M-372 from lake sediment IV at latitude $55.0^{\circ}$ N, and Methanobacterium formicicum M-375 from tidal land soil at latitude $37.0^{\circ}N$, respectively. The isolated anaerobic bacteria could not use sugars as carbon sources. The optimum pH value for the growth of M-251 and M-375 was 6.8, but those for M-253 and M-372 6.5 and 7.0, respectively. The minimum growth temperature of isolated, M-251 and M-253 were $8^{\circ}C$ and the optimum temperature $30^{\circ}C$, while the minimum of M-392 and M-395 were $13^{\circ}C$ and the optimum $37^{\circ}C$. The growth rate of isolates at $17.5^{\circ}C$ were lower by 32-50% than that of $30^{\circ}C$. The isolated Methanobacterium strains such as M-251, M-253, and M-375 have lower cell yield, 0.38-1.21g/1M $CH_4$ than 1.14-1.51g/1M $CH_4$ of Methanosarcina mazei M-372.

• Korean Journal of Environmental Agriculture
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• v.17 no.1
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• pp.70-75
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• 1998

A model of pond system is developed for treatment and recycling of excreta from twenty-five adult dairy cattle. It is composed of wastewater treatment ponds and small fish ponds. Those are three facultative ponds in series; primary-secondary-tertiary pond and these are designed to rear carps without feeding. A pit is constructed at the bottom of primary pond for efficient sludge sedimentation and effective methane fermentation. It is contrived to block into it the penetration of oxygen dissolved in the upper layer of pond water. The excreta from the cattle housed in stalls are diluted by water used for clearing them. The washed excreta flow into the pit. The average yearly $BOD_5$ concentration of influent is 398.7mg/l. That of the effluent from primary, secondary and tertiary pond of the system is 49.18, 27.9, and 19.8.mg/l respectively. Approximate 88, 93, and 95 % of BOD5 are removed in each pond. The mean yearly SS concentration of influent is 360.5 mg/l That of the effluent from each pond is 53.4, 45.7, and32.7mg/l respectively. Approximate 86, 88, and 91% of SS are removed in each pond. The $BOD_5$ concentration of secondary and tertiary pond can satisfy 30mg/l secondary treatment standard. The SS concentration of effluent from tertiary pond, however, is slightly greater than the standard, which results from activities of carps growing in the pond. The average yearly total nitrogen concentration of influent is 206.8mg/l and that of the effluent from each pond is 48.6, 30.8, and 21.0mg/l respectively. Approximate 74, 88, and 90% of total nitrogen are removed in each pond. The mean yearly total phosphorous concentration of influent is 20.7mg/l and that of the effluent from each pond is 5.3, 3.2, and 2.1mg/l respectively. Approximate 97, 98, and 99% of total phosphorous are removed in each pond. The high removal of nitrogen and phosphorous results from active growth of algae in the upper layer of pond water. Important pond design parameters for southern part of Korea -- areal loading of BOD5, liquid depth, hydraulic detention time, free board, and pond arrangement -- are taken up.