• Title, Summary, Keyword: Feeding Strategy

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Production of Glutathione by yeast and Process Monitoring (효모에 의한 글루타치온의 생산과 공정 모니터링)

  • 김춘광;이종일
    • KSBB Journal
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    • v.19 no.3
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    • pp.192-199
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    • 2004
  • In this work the production of glutathione (GSH) by yeast Saccharomyces cerevisiae and the monitoring of the process were studied. In shaking culture the production of GSH was high at initial pH value of 4 and at temperature of 30$^{\circ}C$. But when L-cysteine was added to the culture medium at the beginning of the cultivation, the productivity of GSH was low. In case 0,5% (v/v) of L-cysteine, glycine and glutamic acid were introduced to the culture medium in the exponential cell growth phase, high concentration of GSH (about 90 mg/L) was produced in the bioreactor. A fed-batch operation with stepwise glucose feeding strategy allowed to produce 102 mg/L of GSH. The cultivation processes were on-line monitored by a 2-dimensional fluorescence sensor. A few off-line data such as cell growth, cystein concentration, phosphate concentration and GSH productivity could be well correlated to the fluorescence intensity of some combinations of excitation and emission wavelengths.

Using GIS to Estimate Estuarine Wetlands in Three Major Estuaries and to Quantify Wetland Changes over the Last Century (GIS를 활용한 하구의 습지추정 및 변화추이 분석에 관한 연구)

  • Rho, Paikho;Lee, Chang-Hee
    • Journal of Wetlands Research
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    • v.9 no.2
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    • pp.21-31
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    • 2007
  • Estuarine wetland, where freshwater meets saltwater, is a transitional ecosystem that is valuable ecologically for a variety of reasons, such as feeding and breeding sites for birds, fish, and wildlife. However, research on the spatial distribution and temporal dynamics of estuarine wetlands in Korea is rare. As a fundamental basis for wetland conservation, this study quantified the wetlands in three major estuaries, and evaluated the temporal dynamics of the wetlands since the 1910s. In particular, this study classified the wetland types into mud flat, sand, and emergent-plant types, and estimated the change of each wetland type, using topographic maps produced in the 1910s, 1970s, and 2000s. The wetlands in both the Han and Youngsan River estuaries have declined since the 1910s, but the rate of wetland decline was relatively low before the 1970s, compared to that since the 1970s. The impact of human activities, such as the Youngsan Watershed Comprehensive Development Project and the construction of estuary barrages, has disrupted the estuary cycles and destroyed huge amounts of wetland in the Youngsan estuary. By contrast, estuarine wetlands have been preserved in the small Gahwa estuary, and provide a variety of habitats for plants and wildlife. A special management strategy for wetlands should be established as soon as possible.

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Anaerobic Bacterial Degradation for the Effective Utilization of Biomass

  • Ohmiya, Kunio;Sakka, Kazuo;Kimura, Tetsuya
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.6
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    • pp.482-493
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    • 2005
  • Biomass is originally photosynthesized from inorgainic compounds such as $CO_2$, minerals, water and solar energy. Recent studies have shown that anaerobic bacteria have the ability to convert recalcitrant biomass such as cellullosic or chitinoic materials to useful compounds. The biomass containing agricultural waste, unutilized wood and other garbage is expected to utilize as feed, food and fuel by microbial degradation and other metabolic functions. In this study we isolated several anaerobic, cellulolytic and chitinolytic bacteria from rumen fluid, compost and soil to study their related enzymes and genes. The anaerobic and cellulolytic bacteria, Clostridium thermocellum, Clostridium stercorarium, and Clostridium josui, were isolated from compost and the chitinolytic Clostridium paraputrificum from beach soil and Ruminococcus albus was isolated from cow rumen. After isolation, novel cellulase and xylanase genes from these anaerobes were cloned and expressed in Escherichia coli. The properties of the cloned enzymes showed that some of them were the components of the enzyme (cellulase) complex, i.e., cellulosome, which is known to form complexes by binding cohesin domains on the cellulase integrating protein (Cip: or core protein) and dockerin domains on the enzymes. Several dockerin and cohesin polypeptides were independently produced by E. coli and their binding properties were specified with BIAcore by measuring surface plasmon resonance. Three pairs of cohesin-dockerin with differing binding specificities were selected. Two of their genes encoding their respective cohesin polypeptides were combined to one gene and expressed in E. coli as a chimeric core protein, on which two dockerin-dehydrogenase chimeras, the dockerin-formaldehyde dehydrogenase and the dockerin-NADH dehydrogenase are planning to bind for catalyzing $CO_2$ reduction to formic acid by feeding NADH. This reaction may represent a novel strategy for the reduction of the green house gases. Enzymes from the anaerobes were also expressed in tobacco and rice plants. The activity of a xylanase from C. stercorarium was detected in leaves, stems, and rice grain under the control of CaMV35S promoter. The digestibility of transgenic rice leaves in goat rumen was slightly accelerated. C. paraputrificum was found to solubilize shrimp shells and chitin to generate hydrogen gas. Hydrogen productivity (1.7 mol $H_2/mol$ glucos) of the organism was improved up to 1.8 times by additional expression of the own hydrogenase gene in C. paraputrficum using a modified vector of Clostridiu, perfringens. The hydrygen producing microflora from soil, garbage and dried pelletted garbage, known as refuse derived fuel(RDF), were also found to be effective in converting biomass waste to hydrogen gas.

Climate Change by Global Warming and Its Effects on Production Efficiency of Lactating Dairy Cows in Korea : a Simulation Modeling Approach (지구온난화에 따른 국내 기후변화와 젖소 착유우의 생산효율에 미치는 영향 평가 : 모델 시뮬레이션을 이용한 접근)

  • Lee, Jung-Jin;Lee, Jun-Sung;Kim, Jong-Nam;Seo, Ja-Keum;Jo, Nam-Chul;Park, Seong-Min;Ki, Kwang-Seok;Seo, Seong-Won
    • Korean Journal of Organic Agriculture
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    • v.21 no.4
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    • pp.711-723
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    • 2013
  • The objectives of this study were to access climate change by global warming in Korea, and to investigate its effects on production efficiency of lactating dairy cows. Two regions, Daegu and Daekwanryung, were selected to represent a warm and a cold area, respectively. Time-series analyses on meteorological records for 25 years (from January 1, 1988 to December 31, 2012) revealed significant and different climate changes in two regions. In the warm area there has been a significant (P<0.05) increase in low temperature during the summer, which can cause heat stress to the animal. On the other hand, a decrease in low temperature during the winter was observed in the cold region (P<0.01), and cold stress in winter can thus be an issue in this region. Simulations using a model integrated the Korean feeding standard for dairy cattle and the environmental effect module of Cornell Net Carbohydrate and Protein System, indicated that a reduction in feed efficiency can be a problem during the winter in the cold region while during the summer in the warm area. We conclude that the effect of climate change by global warming varies in different areas in Korea and a region-specific management strategy should be developed in order to maintain productivity, health and welfare of lactating dairy cows.

Strategy to Improve the Productivity of Broilers: Focusing on Pre-Starter Diet (초이사료 배합설계를 통한 육계 생산성 증대방안)

  • Nam, Doo Seok;Lee, Jinyoung;Kong, Changsu
    • Korean Journal of Poultry Science
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    • v.42 no.3
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    • pp.247-256
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    • 2015
  • There are approximately 1,500 broiler farms in Korea, each raising 55,000 birds. Ninety-five percent of the farms are contracted with Integration Company. According to the Korean broiler performance index, broilers in Korea are marketed at 32 days with 1.52 kg of body weight. In contrast, the market age and body weight of broilers are 47 days/2.8 kg in the United States and 42 days/2.5 kg in Europe. Because of the younger market age of the Korean broiler, the pre-starter feed is important. Chicks exhibit poor absorption of dietary nutrients up to 7 days after hatching due to an immature digestive system and low enzyme secretion rate and activity. At the beginning of hatching, chicks obtain their nutrients from the egg yolk sac. It is highly recommended that chicks, after consuming the nutrients in the egg yolk sac, are given supplemented pre-starter feed to increase early growth rates and improve the performance of broiler production. Pre-starter nutrient requirements are not expressed in NRC, so Korean feeding standards for poultry and commercial breeding companies determine the nutrient requirements of pre-starter broiler chickens. Three approaches are followed to formulate specially designed pre-starter feeds for broiler chicks: (i) selective use of raw materials, (ii) proper standards of nutrient supply, and (iii) application of feed additives such as exogenous enzymes. In the selection of raw materials, those with high digestibility can be used. The absorption rate of carbohydrates in grains can be increased through feed processing at high temperature and high pressure. Soy proteins and fish meal can also be added as protein sources. As an energy source, vegetable oils are preferred over animal fats because of the former's high digestibility. It is suggested that the levels of proteins and amino acids are higher in pre-starter feed than in starter feed. With regard to energy, the sources of energy are more important than the levels of energy in feed. Feed additives such as exogenous enzymes can be used to improve nutrient digestibility. In addition, organic acids and plant extracts can be used as alternatives to animal growth promoters to stimulate immunity and prevent diseases. The growth performance of broilers is affected by various factors, such as management and disease control, in addition to the nutritional strategy; however, nutritional strategies play an important role in improving the productivity of broilers. Therefore, nutritional strategies, along with management and disease control, are required for improving the productivity of broilers in Korea.

The Development and Life Table Parameters of Tetranychus kanzawai (Acarina: Tetranychidae) on Leaves of 'shiranuhi' and Japanese Violet in the Laboratory (한라봉과 왜제비꽃 잎에서 차응애의 발육과 생명표 통계량)

  • Hyun, Heejeong;Kim, Subin;Kim, Dong-Soon
    • Korean journal of applied entomology
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    • v.59 no.2
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    • pp.153-163
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    • 2020
  • This study was conducted to evaluate the fitness of Tetranychus kanzawai Kishida on different host plants: young and old leaves of the mandarin orange 'shiranuhi' ((Citrus unshiu × C. sinensis) × C. reticulata), Japanese violet (Viola japonica Langsd.) and kidney bean (Phaseolus vulgaris L.). The development and oviposition experiments were conducted at constant temperatures (20, 25 and 30℃) and a life table parameters were estimated. T. kanzawai could complete it's development on 'shiranuhi' young leaves, japanese violet and kidney bean, while all died during the immature period on 'shiranuhi' old leaves. The total developmental period of T. kanzawai feeding on 'shiranuhi' young leaves was 17.4, 13.4 and 10.2 days at each temperature, respectively, which was longer than 16.1, 9.5 and 7.0 days of kidney bean. The female longevity of T. kanzawai on young leaves of 'shiranuhi' were 19.1, 15.0 and 12.3 days at each temperature, respectively, and there was no significant difference from 22.1, 14.1 and 10.9 days investigated from kidney bean. The fecundity was 18.1, 23.9 and 17.8 eggs per female, which was less than them of japanese violet and kidney bean at each temperature, respectively. As a result of estimating the life table parameters based on the experimental data, intrinsic rate of increase (rm) were significantly different from each other, and appeared in the following order: kidney (0.1542, 0.2563 and 0.3251), japanese violet (0.1087, 0.2007 and 0.2673) and 'shiranuhi' young leaves (0.0868, 0.1002 and 0.1217) at each temperature, respectively. Finally, the management strategy against T. kanzawai in citrus orchards was discussed based on the results.

The Effect of Exercise Intensity on Changes in Neuronal Nitric Oxide Synthase Expression in the Hippocampus and Cerebral Cortex of Obese Mice (고지방식이로 유도된 비만 마우스의 해마 및 대뇌피질에서 운동강도에 따른 nNOS 발현의 변화)

  • Baek, Kyung-Wan
    • Journal of Life Science
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    • v.29 no.1
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    • pp.18-28
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    • 2019
  • Recent studies reported that obesity upregulated the expression of neuronal nitric oxide synthase (nNOS) and regulated particular behavior patterns in animal models. They also reported that ameliorated the increase in nNOS expression and decreased depression and anxiolytic effects. Thus, exercise seems to be an effective strategy for improving brain function by downregulating nNOS. However, the immune response differs greatly, depending on the exercise intensity. The aim of the present study was to investigate differences in brain nNOS expression in obese C57BL/6 mice that performed exercise of different intensities. Obesity was induced in 6-wks-old mice (n=35) by feeding a 60%-fat diet for 6-wks. A control (CON) group (n=14) was fed a normal diet. At the end of the induction 6-wks period of obesity, seven animals in the CON group and obesity-induced group were sacrificed to confirm obesity induction (preliminary experiments and confirmation of visceral fat accumulation). The remaining animals were then used in an 8-wks exercise intervention. Other than the CON (n=7), the obesity-induced animals were divided into the following groups: high-fat diet (HFD, n=7), HFD-low intensity (HFD-LI, n=7, 12 m/min for 75 min), HFD-moderate intensity (HFD-MI, n=7, 15 m/min for 60 min), and HFD-high intensity (HFD-HI, n=7, 18 m/min for 50 min). The exercise was performed on an animal treadmill. The expression of the nNOS protein in the hippocampus was significantly higher in the HFD group as compared with that in the CON group (p<0.01). However, there was no difference in the hippocampal expression of the nNOS protein in the other exercise groups as compared with that in the CON group. In contrast, nNOS expression in the HFD-HI group was significantly lower than that in the HFD-LI group (p<0.05). The expression of phosphorylated Akt (pAkt) was significantly higher in all the exercise groups as compared with that in the CON and HFD groups. There was no difference in the expression of pAkt in the cerebral cortex among groups, and the expression of pAkt in the cerebellum was significantly higher in the HFD-HI group as compared with that in the CON group (p<0.05). There were also no between-group differences in pAkt expression in the cerebellum among the various exercise groups. In conclusion, nNOS seems to be overexpressed in response to obesity, and it appears to be downregulated by exercise. Relatively high-intensity exercise may be effective in improving brain function by downregulating nNOS.

A Study on Recognition and Practice of Teakyo by Pregnant Women (임부의 태교인식과 태교실천에 관한 조사연구)

  • Shin, Yong-Bun;Koh, Hyo-Jung
    • Korean Journal of Women Health Nursing
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    • v.6 no.1
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    • pp.142-152
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    • 2000
  • This study is a descriptive study to offer an actual basic data as Nursing intervention strategy of nurses before delivery in order that pregnant women in Korea may effectively practice Taekyo by examining the relation after apprehending level of recognition and practice of our pregnant women about Taekyo. This study collected questionnaires from 801 pregnant women who visited general hospitals in 10 areas(Seoul, Daejon, chunan, Daegu, Kummi, $Ky{\check{o}}ngju$, $P{\ddot{o}}hang$, Busan, $J{\ddot{o}}nju$, and $Y{\ddot{o}}nkwang$) for prenatal care through an outpatient obstetrics and gynecology from July 15 to August 30, 1999. This study used the tool of lee, Ki Young(1993) revised an complemented by investigator to measure recognition of Taekyo and the tool of Jang, Shun Buk and Park, Young Ju(1996) revised and complemented by investigator to measure practice of Taekyo. The Cronbach's alpha value of each tool was .88 in recognition of Taekyo, while the value was .90 in practice of Taekyo. For data analysis, this study used the descriptive and statistical analysis, Pearson correlation, t-test, ANOVA, Tukey's post hoc contrast, and Stepwise multiple regression in accordance with the purpose of this study with using SPSS Win 7.5 program. The results were as follows ; 1. The practice of Taekyo was low in comparison with recognition of Teakyo by showing average 4.28 points and standard deviation 0.48 at level of recognition of pregnant women about Taekyo on the basis of 5 points and showing to show average 2.81 points and standard deviation 0.36 at practice level on the basis of 4 points. 2. They showed the higher level of recognition on Taekyo at high educational background of pregnant woman(F=3.735, p=.005), Roman catholicism (F=4.570, p=.002), satisfied married life(F=5.448, p=.004), high monthly income(F=6.096, p=.000) and cases of hoping pregnancy(F=2.525, p=.012). 3. They showed the higher level of practice on Taekyo at high educational background of pregnant woman(F=2.883, P=.022), Roman catholicism(F=3.616, p=.032), satisfied married life(F=19.924, p=.000), good health condition(F=2.386, p=.017), cases of hoping pregnancy(F=0.677, p=.000), cases of planning pregnancy with husband(F=3.024, p=.001), cases of regular prenatal care before delivery(F=0.241, p=.005), cases of maternal breast feeding (F=9.132, p=.000), and the number of less children(F=2.763, p=.041). 4. In result of examining correlation between recognition and practice of Taekyo, they showed high level of practice on Taekyo under high level of recognition of pregnant women on Taekyo by showing the statistically significant correlation. 5. In result of examining the related factors that affect recognition and practice of Taekyo y the object, practice of Taekyo had 16.8 percents of explanatory range, purpose of practicing Taekyo 8.5 percents of explanatory range, and monthly income 1.9 percent of explanatory range as variables of affecting recognition of Taekyo. The total explanatory range was 27.2 percents, Recognition of Taekyo had 16.1 percents of explanatory ragne, time of starting Taekyo 3.2 percents, health condition 2.2 percents of explanatory range, condition of hoping pregnancy 1.1 percent of explanatory range, satisfaction of married life 0.8 percent of explanatory range, and religion 0.6 percent of explanatory range as variables of affecting practice of Taekyo. The total explanatory range was 24.0 percents.

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Effects of Dietary Nutrient Levels on Growth Performance, Blood Urea Nitrogen, and Meat Quality in Finishing Pigs (비육돈에 있어서 영양소 및 원료 첨가수준이 다른 사료의 급여가 생산성, 혈중 요소태질소 및 육질특성에 미치는 영향)

  • Shin, Seung-Oh;Cho, Jin-Ho;Kim, Hae-Jin;Chen, Ying-Jie;Yoo, Jong-Sang;Wang, Yuan;Huang, Yan;Kim, In-Ho
    • Food Science of Animal Resources
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    • v.27 no.4
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    • pp.387-391
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    • 2007
  • This study was conducted to evaluate effects of dietary nutrient levels on growth performance, blood urea nitrogen, and meat quality in finishing pigs. A total of ninety six pigs ($Landrace{\times}Yorkshire{\times}Duroc$) were used in this 66 day study. Dietary treatments included 1) T1 (ME 3,441 kcal/kg, CP 16.30%, Lysine 0.93%), 2) T2 (ME 3,433 kcal/kg, CP 17.00%, Lysine 1.00% and 3) T3 (ME 3,449 kcal/kg, CP 17.00%, Lysine 1.00%). During the overall period, there were no significant differences in ADG (average daily gain), ADFI (average daily feed intake), gain/feed ratio or BUN (blood urea nitrogen) among the treatments (p>0.05). The $b^*$ value of M. longissimus dorsi muscle color significantly increased (p<0.05) with T3 treatment compared to T2 treatment. However, there were no differences in the $L^*\;and\;a^*$ values, pH, M. logissimus dorsi area, drip loss, cooking loss, TBARS and WHC (water holding capacity) for pigs fed the various treatments (p>0.05). The total feed cost per kg of weight gain was not significantly different among the various dietary treatments (p>0.05). In conclusion, these results show no effects of dietary nutrient levels on growth performance and meat quality in finishing pigs, and also suggest that a high nutrient density diet may not be a beneficial feeding strategy for finishing pigs in terms of cost.

Evaluation on Feed-Nutritional Change of Food Waste According to Different Processing Methods and Trouble-shooting Strategy (음식물쓰레기의 가공처리방법별 사료영양소 함량 변화 평가 및 문제점 개선 방안)

  • Jee, K.S.;Baik, Y.H.;Kwak, W.S.
    • Journal of Animal Science and Technology
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    • v.47 no.4
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    • pp.513-524
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    • 2005
  • This study was conducted to introduce recycling procedures of food waste(FW) as feed according to the dehydration, semi-dehydration fermentation and liquid fermentation methods through the on-site survey of companies related, to trace physico-chemical components and nutritional losses depending upon the processing stage for each method and finally to suggest more desirable methodology for the efficient utilization of FW as animal feed. For the dehydration method, dewatering of FW alone reduced(P<0.05) moisture(approximately 10%) and ether extract contents and increased(P<0.05) fiber contents. Dewatering and subsequent dehydration of FW decreased(P<0.05) contents of ether extract, limiting amino acids such as lysine, methionine and histidine, pepsin digestibility of protein by half, and NaCl content by 40%, increased(P<0.05) contents of fiber, crude ash, Ca and P, and did not alter(P>0.05) pH. The semi-dehydration fermentation method of FW did not affect(P>0.05) the chemical components, pepsin digestibility of protein, pH and NaCl content. For the liquid fermentation method, pasteurization and fermentation of FW decreased(P<0.05) contents of dry matter, ether extract, crude fiber, lysine and NaCl; however, it did not affect(P>0.05) other chemical components, pepsin digestibility of protein and pH. Among the processing methods, nutrient losses were highest for the dehydration method(25% of metabolizable energy loss, 12% of organic matter loss) and little for the semi-dehydration and liquid fermentation methods. The on-site survey of companies related revealed that the existence of foreign materials in FW products were problematic for all the three companies surveyed, thus it was necessary to develop a more efficient screener. Before feeding FW-containing diets to pigs, high quality of protein and energy feedstuffs needed to be fortified for the dehydration method. For the semi-dehydration fermentation method, the scientific diet formulation technology was required at the initial mixing stage. For the liquid fermentation method, possibly most energetic and proteinaceous feeds needed to be supplemented for the normal animal growth.