• Asian-Australasian Journal of Animal Sciences
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• v.28 no.11
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• pp.1606-1613
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• 2015

This study was carried out to investigate the effects of Yerba Mate (YM) supplementation on nutrients' degradation, in vitro dry matter disappearance, gas production and rumen ammonia concentration. Three rumen-fistulated Holstein Friesian cows were used for the in situ incubations and provided rumen liquor for in vitro incubations. The inclusion of YM in a control diet (pasture+pellets) affected some in sacco degradation parameters. YM supplementation decreased the effective degradability and degradation rate of pasture crude protein (CP), and it seems to slow down the degradation of pasture neutral detergent fiber. A significant increase of degradation of pasture acid detergent fiber (ADF) was detected after YM inclusion in the control diet. YM supplementation reduced in vitro gas production of pasture and ammonia concentration of pellets. The addition of YM in ruminant diet could decrease ammonia production and increase protein availability for productive purposes. The moderate presence of tannins in YM could have affected the degradation kinetics of pasture CP and ADF and the ammonia production of pellets.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.6
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• pp.519-522
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• 2004

In the course of anaerobic storage of excess sludge, odors due to chemicals such as hydrogen sulfide are produced. These odors cause many problems. Many methods have been developed to eliminate odors, but all current methods are not only costly, but also largely inef­fective. In this paper, we investigate the process of transformation of sludge microorganism cul­tures through intense aeration under nutrient-poor conditions, in terms of the selective adjust­ment and control of microorganism culture. The aerated sludge is subsequently returned to the adjusting pool, where the microorganisms inhibit odors, thus the excess sludge itself will act as an odor inhibitor. The process can be verified in terms of viability, in that the degradation capac­ity of the sludge was maintained after the intensely-aerated sludge was returned to the treat­ment system.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.4
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• pp.39-50
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• 2002

Field experiment was performed to investigate water and nutrient mass balances in paddy field with groundwater irrigation from May to October, 2001. The total water inflow was about 1,183mm in which rainfall, overflow from upstream paddy, and groundwater irrigation accounted for 43, 30, and 27%, respectively. Notice that the precipitation of the study period was less than the average annual precipitation. The total drainage was almost balanced with the inflow and more than half of it was occurred by surface drainage. From the nutrient mass balance analysis, the T-P output (17.56kg/ha) was estimated slightly lower than the input (20.90kg/ha) and the T-N output (130.41kg/ha) was slightly greater than the input(129.24kg/ha). However, the difference was within the expectation and the nutrient mass was thought to be balanced considering uncertainties in field experiment and other activities not included in the study such as algae and soil microorganisms. The surface discharge of nutrient, which was about 10% of total nutrient output, was mainly affected by fertilization and rainfall runoff. Therefore, prudent surface drainage plan might be necessary particularly for the fertilization period to prevent degradation of receiving water quality. The study was performed under abnormally low rainfall compared to the average annual rainfall record, and further monitoring in diverse rainfalls and irrigation methods is recommended to estimate nutrient behavior in the paddy field more reasonably.

• KCID journal
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• v.3 no.2
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• pp.11-19
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• 1996

Lake Soyang, the largest man-made lake in Korea, has been experiencing water quality degradation because of excessive nutrient loads from the watershed. Objective of this paper is to describe land uses in and TP and TN loading characteristics from the lak

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.11
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• pp.1569-1574
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• 2005

The in situ nylon bag degradation and in vitro intestinal digestibility of dry matter (DM), and crude protein (CP) of mulberry (Morus alba) plant fractions was studied at four harvest stages, 3 (W3), 5 (W5), 7 (W7) and 9 (W9) weeks. Degradability of DM and CP of the whole plant and stem fractions declined significantly (p<0.01) with advancing plant maturity in the order W3>W5 and W7>W9 and W3>W5>W7>W9, respectively. The degradation of DM and CP of the leaf fraction was also influenced by plant maturity but no trend was observed. The degradation of DM and CP of the whole plant and leaves increased rapidly during the first 48 and 24 h of incubation, respectively, when maximum degradation was reached. In vitro intestinal digestibility of CP was more influenced by the residence time in the rumen than by plant maturity. This study showed that mulberry is suitable as a supplement, particularly to low-quality roughages, in providing a source of rapidly available nitrogen to the rumen microbes, hence improving the roughage degradability and intake.

• Microbiology and Biotechnology Letters
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• v.31 no.1
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• pp.83-89
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• 2003

2,4-Dichlorophenoxyacetic acid (2,4-D) as a widely used herbicide has caused serious environmental problems because of its difficult decomposition in nature. We isolated the strain capable of metabolizing 2,4-D as sole carbon and energy source by an enrichment culture technique from the 2,4-D contaminated soil collected at orchard in Gwangju, Korea. This strain was identified tentatively as Aeromonas sp. NOH2. With this strain, we established the response surface methodology (Box-Behnken Design) to optimize the principle parameters for maximizing biodegradation of 2,4-D such as culture pH, temperature, and nutrient concentration in liquid batch culture. The ranges of parameters were obtained from preliminary works done at our laboratory and chosen as 5.5, 6.5, and 7.5 for pH, 25, 30, and $35^{\circ}C$ for temperature, and 5, 20, and 35 g/1 nutrient concentration. Initial concentration of 2,4-D was 500 ppm and nutrient source was tryptic soy broth. The experimental data were significantly fitted to a second order polynomial equation using multiple regression. The most important parameter influencing 2,4-D degradation and biomass production was nutrient concentration. For 2,4-D degradation, the optimum values of pH and temperature, and nutrient concentration were obtained at pH (6.5), temperature (31.8 to $32.1^{\circ}C$), and nutrient concentration (29.6 to 30.1.0 g/1).

• Korean Journal of Agricultural Science
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• v.26 no.2
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• pp.25-32
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• 1999

An in vitro study was conducted to examine the effects of the addition of activated charcoal (AC) on the ruminal fermentation characteristics, nutrient disappearance, and ruminal gas production. AC was added at the levels of 0.00, 0.25, and 0.50 % to each of the four types of diets (roughage/concentrate ratio : 8/2, 6/4, 4/6 and 2/8), respectively. Although not significant, ruminal pH tended to increase by adding AC, and as the concentrate level increased, ruminal pH decreased (P<0.05). Acetate concentration and acetate/propionate molar ratio tended to decrease in AC diets. but molar % of propionate tended to increase by the addition of AC. Ruminal degradation of dry matter, crude protein, NDF, ADF, and hemicellulose in AC diets tended to increase than in non-AC diet, however, no tendency in ruminal degradation of crude fat was observed. As the concentrate level increased, rumunal degradation of dry matter and nutrients in AC diets increased significantly(P<0.05). Ruminal gas production tended to decrease in the 0.50 % AC diets, however, it tended to increase in high roughage diets. Although there appeared some beneficial effects in adding AC to ruminant diets in this study, more works should be done with AC before we can make clear conclusion on the use of AC in the ruminant diets.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.11
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• pp.1604-1609
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• 2008

A series of in vitro and in vivo experiments were conducted to investigate the effects of the mixture of Tween 80 and cellulolytic enzymes (xylanase and cellulase) on total tract nutrient digestibility and rumen cellulolytic bacterial adhesion rates in Holstein steers. Ground timothy hay sprayed with various levels of Tween 80 and cellulolytic enzymes was used as substrates in an in vitro experiment to find out the best combinations for DM degradation. The application level of 2.5% (v/w) Tween 80 and the combination of 5 U xylanase and 2.5 U cellulase per gram of ground timothy hay (DM basis) resulted in the highest in vitro dry matter degradation rate (p<0.05). Feeding the same timothy hay to Holstein steers also improved in vivo nutrient (DM, CP, CF, NDF and ADF) digesibilities compared to non-treated hay (p<0.05). Moreover, Tween 80 and enzyme combination treatment increased total ruminal VFA and concentrations of propionic acid and isovaleric acid with decreased acetate to propionate ratio (p<0.001). However, adhesion rates of Fibrobacter succinogenes and Ruminococcus flavefaciens determined by Real Time PCR were not influenced by the treatment while that of Ruminococcus albus was decreased (p<0.05). The present results indicate that a mixture of Tween 80 and cellulolytic enzymes can improve rumen environment and feed digestibility with variable influence on cellulolytic bacterial adhesion on feed.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.8
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• pp.1076-1083
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• 2000

The aim of this study was to evaluate the effect of Aspergillus oryzae fermentation extract (AFE) on in situ degradation of the various concentrates, forages and by-products in Taiwan. The in situ trial was conducted to determine the effect of AFE on the rate of ruminal degradation of dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) of the various local available feedstuff commonly used for dairy cattle. Two ruminal fistulated cows were arranged into a two by two switchback trial. Two dietary treatments were control without AFE inclusion diet and diet with 3 g of AFE (Amaferm) added daily into the total mixed ration (TMR). Results showed that effect of AFE inclusion on the ruminal degradability of concentrates vary; soybean meal is the most responsive feedstuff, corn is the next, whereas full-fat soybean did not response the AFE inclusion at all. The inclusion of AFE significantly depressed most of the nutrient degradation of the concentrates of soybean meal in the first 12-hour in situ incubation. The effect declined in the next 12 hours. Rapeseed meal showed a different trend of response: addition of AFE improved its NDF degradation. The inclusions of AFE significantly improved ADF degradation of roughage after 24 or 48 hours of incubation. However, corn silage and peanut-vines showed a different trend. Effects of AFE inclusion on the by-products degradability were inconsistent. Most of nutrients in rice distillers grain and some in beancurd pomace did show increased degradation by the AFE inclusion.

• Advances in environmental research
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• v.9 no.1
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• pp.1-17
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• 2020

Pharmaceutically active compounds (PhACs) have become an environmental havoc in last few decades with reported cases of antibiotic resistant bacteria (ARB) and antibiotic resistant genes (ARGs), lethal effects over aquatic organisms, interference in natural decomposition of organic matter, reduced diversity of microbial communities in different environmental compartments, inhibition of growth of microbes resulting in reduced rate of nutrient cycling, hormonal imbalance in exposed organisms etc. Owing to their potential towards bioaccumulation and persistent nature, these compounds have longer residence time and activity in environment. The conventional technologies of wastewater treatment have got poor efficiency towards removal/degradation of PhACs and therefore, modern techniques with efficient, cost-effective and environment-friendly operation need to be explored. Advanced oxidation processes (AOPs) like Photocatalysis, Fenton oxidation, Ozonation etc. are some of the promising, viable and sustainable options for degradation of PhACs. Although energy/chemical or both are essentially required for AOPs, these methods target complete degradation/mineralization of persistent pollutants resulting in no residual toxicity. Considering the high efficiency towards degradation, non-toxic nature, universal viability and acceptability, AOPs have become a promising option for effective treatment of chemicals with persistent nature.