• 한국미생물·생명공학회지
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• 제10권1호
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• pp.45-52
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• 1982

A fungus with the highest protopectinase productivity was selected among 205 strains isolated from the soil and identified as a Verticillium sp. The Verticillium sp. was cultivated on wheat bran and the crude extruct of its culture medium showed the highest protopectinase activity on the following conditions: 3 days of cultivation time, 27$^{\circ}C$ of cultivation temperature, 1.2 $m\ell$/g wheat bran of water content, and reinforcement of ammonium nitrate and calcium chloride at the concentration of 0.5 and 0.02%, respectively. The optimum conditions for pectin production from Citrus peel pulp by the protopectinase were consequently obtained as follows: 20$m\ell$/g of liquid volume-to-pulp weight ratio, 4$0^{\circ}C$ of reaction temperature, and 4 of reaction pH. The higher the enzyme concentration, the better the yield of pectin and the shorter the reaction time. Total 45.6mg of pectin/g peel was produced by 1 hour reaction at the enzyme concentration of 10.5 units/$m\ell$. Molecular weight of the pectin produced by the enzyme was estimated to be about 62,000 by Smit and Bryant's method.

• 한국환경보건학회지
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• 제17권1호
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• pp.120-128
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• 1991

Saccharomyces cerevisiae was immobilized by incubating iron oxides with calcium alginate, and by polyacrylamide entrapment to use repeatedly for the conversion of glucose to ethanol. Magnetic and non-magnetic immobilized yeast and polyacrylamide immobilized yeast were compared with the native yeast a batch-fermentation of ethanol from glucose. Three kinds of immobilized yeast tended almost identically, having ethanol productivity as well as the final yield about the same to what was found for the native yeast. The long-term operational stability of three kinds of immobilized yeast were significant difference according as immobilized yeast activation or non-activation before ethanol fermentation. In the non-activation they lost their activity of fermentation rapidly in the beginning stage an slower at a later stage. On the other hand, in the activation with nutrient media, their activities were increased to some extent and stable in the later stage. The cell count of three kinds of immobilized yeast after activiation by incubating nutrient media, increased by a factor of about 45 to 48, whereas the fermenting capacity increased by a factor of 174 to 178. In the prearation of immobilized biocatalysts, magnetic matter does not seem to have any adverse affect on the properties of the microorganism. The immobilized biocatalysts by utilizing magnetic matter have some advantages, especially in application of viscous media or insoluble particle-containing media, for this work was linked with microbial utilization of environmental wastes and elimination of envirnmental pollutant.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.331-336
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• 2001

Aragonite type of precipitated calcium carbonate was synthesized by the successive reaction with hybridization of waste scallop shells with limestone. In the first step, carbonation was performed by using calcined limestone with low brightness, followed by the additional carbonation using calcined-hydrous scallop shells with high brightness. The temperature and the amount ratio of calcined limestone to calcined-hydrous scallop shells were examined as parameters in the experimental conditions. The products were characterized by XRD, SEM. in addition to measurements of brightness index. the specific surface area, and bulk density. The amount ratio of limestone to scallop shell affected not only the brightness but also morphologies of products. The increase in relative amounts of limestone leads to decrease in brightness and bumpy surface of particles. High temperature reaction produces aragonite particles with longer sizes and higher bulk densities. This study has made an attempt to establish the synthesis of aragonite with high brightness and high strength by utilization of waste scallop shells.

• 한국대기환경학회지
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• 제12권4호
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• pp.449-457
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• 1996

The main purpose of this study was to investigate sulfur dioxide removal performance of flue gas desulfurization system utilizing a Spray Absorption/Drying Reactor. In this system, the size of droplets was considered the most significant factor and tested using a PDA system. Lime slurry flow rate, operating temperature, calcium/sulfur (Ca/S) ratio and applied air pressure were selected as major operation variables and tested/analyzed in terms of system performance. The results are as follows. 1. The $SO_2$ removal efficiencies were 49%, 74%, 85% for Ca$(OH)_2$ slurry flow rate of 10, 20, 30 ml/min, which implies that the increase of slurry flow rate improves removal efficiency. The optimum slurry flow rate in this study was, however, considered 20 ml/min because of constraints of system troubles and absorbent utilization. 2. As Ca/S ratio increased, $SO_2$ removal efficiency was observed to increase. 3. As air pressure, at the atomizing nozzole, increased from 3 to 5 $kg/cm^2, SO_2$ removal efficiency increased from 74% to 80%, because of droplet size reduction due to pressure increase during atomizing process and the increase of surface area, helping mass transfer between gas and liquid phase.

• 한국가금학회:학술대회논문집
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• 한국가금학회 2003년도 제20차 정기총회 및 학술발표회
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• pp.89-90
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• 2003

중탄산소다 함유 대두유 사료는 급성기 반응에 의한 생산성(증체, 사료효율, 칼슘밸런스, 뇨질소 배설량 및 NB) 감소 완화작용이 있었으며, 이때 에너지원의 흡수 증가에 의한 대사에너지 값의 상승과 인 발란스의 증가 및 적혈구 세포액중의 SOD 및 순환 세룰로플라민스의 활성 감소가 관찰되었다. 본 결과는 급성기 반응중의 사료에너지 이용과 전해질 농도는 항산화계의 변화와 상관관계가 있다는 것을 나타내었다.

• Food Science and Biotechnology
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• 제15권4호
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• pp.516-522
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• 2006

This study was to assess the antimicrobial action of 2-hydroxyethyl ${\beta}$-undecenate purified from cumin (Cuminum cymium L.) seed against the oral anaerobe, Streptococcus mutans, which is associated with gingivitis, specifically focusing on the catabolic effect. 2-Hydroxyethyl ${\beta}$-undecenate inhibited the acid production and growth of S. mutans after 30 hr incubation at 50 mM. The glycolysis of S. mutans with glucose as substrate was similarly sensitive to 2-hydroxyethyl ${\beta}$-undecenate, with 70% inhibition of glucose utilization at 5 mM and 90% inhibition at 50 mM. In addition, this substance potently inhibited the glycolysis enzyme, glyceraldehyde-3-phosphate dehydrogenase (GADP); the phosphoenolpyruvate, glucose phosphotransferase (Glucose-PTS); and membrane ATPase, in a concentration dependent manner. The $IC_{50}$ values for inhibition of GADP, Glucose-PTS, and ATPase were 1, 0.9, and 5 mM, respectively. Furthermore, 2-hydroxyethyl ${\beta}$-undecenate inhibited teeth calcium ion elution by 80% at 50 mM. These results suggest that 2-hydroxyethyl ${\beta}$-undecenate is a potent inhibitor of carbohydrate metabolism and the growth of S. mutans JC-2.

• Advances in concrete construction
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• 제7권4호
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• pp.263-275
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• 2019

In the present work, Granulated Blast Furnace Slag (GBFS) and Fly ash (FA) were used as partial replacement of Natural Sand (NS) and Ordinary Portland Cement (OPC) by weight. One control mix, one with GBFS, three with FA and three with GBFS-FA combined mixes were prepared. Replacements were 50% GBFS with NS and 20%, 30% and 40% FA with OPC. Preliminary investigation on development of compressive strength was carried out at 7, 28 and 90 days to ensure sustainability of waste materials in concrete matrix at room temperature. After 90days, thermo-mechanical study was performed on the specimen for a temperature regime of $200^{\circ}-1000^{\circ}C$ followed by furnace cooling. Weight loss, visual inspection along with colour change, residual compressive strength and microstructure analysis were performed to investigate the effect of replacement of GBFS and FA. Although adding waste mineral by-products enhanced the weight loss, their pozzolanicity and formation history at high temperature played a significant role in retaining higher residual compressive strength even up to $800^{\circ}C$. On detail microstructural study, it has been found that addition of FA and GBFS in concrete mix improved the density of concrete by development of extra calcium silicate gel before fire and restricts the development of micro-cracks at high temperature as well. In general, the authors are in favour of combined replacement mix in view of high volume mineral by-products utilization as fire protection.

• Asian-Australasian Journal of Animal Sciences
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• 제19권10호
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• pp.1422-1428
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• 2006

In order to investigate the effect of different levels of niacin supplementation on growth, nutrient utilization, their balance and blood biochemical profile, 15 male buffalo calves (9-10 months of age, $88.4{\pm}4.37kg$ average body weight) were divided into 3 equal groups each of 5 calves, following a completely randomized design, and fed individually for 120 days with wheat straw and concentrate mixture to meet their nutrient requirements. In addition calves were supplemented with 0 ppm (control, group I), 100 ppm (group II) and 200 ppm (group III) niacin. After 90 days of experimental feeding a metabolism trial was conducted to estimate the digestibility of nutrients and their balance. Fortnightly body weights were recorded to assess their growth rate and blood was collected from the jugular vein at day 0 and subsequently at 30-day intervals from all the experimental buffalo calves to study blood biochemical parameters. Results showed that intake and digestibility of dry matter, organic matter, crude protein, ether extract, total carbohydrates, neutral detergent fibre, acid detergent fibre, cellulose and hemicelluloses were statistically similar in the 3 groups. Buffalo calves in all three groups were in positive nitrogen, calcium and phosphorus balance, without showing any significant effect of the treatments. Dry matter, crude protein, digestible crude protein and total digestible nutrient intake ($g/d/kgW^{0.75}$) were similar in the control and niacin supplemented groups. Digestible crude protein (%) and total digestible nutrients (%) in the ration of the 3 groups were 8.07, 7.99, 7.92 and 56.70, 56.63, 56.74, respectively, and were comparable among the groups. The average daily gain (g) in-group II (567.50) was not significantly (p>0.05) higher than group I (500.0) and group III (510.0). Blood biochemical constituents (glucose, total protein, albumin, globulin, urea-N, insulin) showed no significant effect of niacin supplementation. However, serum cholesterol (mg/100 ml) was significantly (p<0.01) lower in the 200 ppm niacin-supplemented group than in the control and 100 ppm niacin-supplemented groups. It can be concluded that supplementation of niacin at 100 and 200 ppm in the diet of buffalo calves had no significant beneficial effect on their growth and nutrient utilization.

• Asian-Australasian Journal of Animal Sciences
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• 제30권10호
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• pp.1442-1449
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• 2017

Objective: This study investigated the effect of microbial phytase supplementation on growth performance, tibia ash, plasma parameters, apparent ileal digestibility (AID) of amino acid (AA) and apparent digestibility of nutrients in Youxian Sheldrakes fed with low-phosphorus (P) cornsoybean diets. Methods: A total of 350 Youxian Sheldrakes (7d old) were randomly divided into 5 treatment groups: positive control (PC) group has adequate available P diet (0.42% and 0.38%, starter and grower), negative control (NC) group were deficient in available P (0.32% and 0.28%, starter and grower) and NC diet was supplemented with 3 levels of microbial phytase (500, 750, and 1,000 U/kg). Results: Dietary supplementation of phytase in NC diet improved the average daily gain, increased the levels of serum calcium (Ca), tibia Ca and P, AID of AA and apparent digestibility of energy and Ca in starter stage (p<0.05). There was an increased (p<0.001) in the utilization of P from 17.3% to 23.9%. Phytase supplementation (1,000 U/kg) has shown that the AID of His, Thr, Val, indispensable AA, Glu, Pro, and dispensable AA was higher (p<0.05) than that of NC. Moreover, phytase supplementation improved (p<0.05) serum and tibia Ca and P, AID of AA and apparent digestibility of dry matter, crude protein, energy, P and Ca, and reduced (p<0.05) feed to gain ratio (F/G) and the levels of serum alkaline phosphatase in grower stage. Likewise, an increase (p<0.001) in the utilization of P was noticed from 12.6% to 17.2%. Supplement phytase at 750 U/kg improved the AID of His, Thr, Asp, Cys, Pro, and Ser (p<0.05). Conclusion: The microbial phytase supplement could improve growth performance, AID of some AA and apparent utilization of other nutrients in Youxian Sheldrakes, and reduce excreta P load to environment.

• 한국가정과교육학회지
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• 제33권2호
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• pp.45-56
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• 2021

본 연구는 국민건강영양조사 제 7기 2016년~2018년 자료를 활용하여, 만 12~18세 남녀 청소년 1,068을 대상으로 영양표시 이용여부에 따른 식습관 및 영양소 섭취와 건강행태 등을 비교하여 영양표시 이용과 올바른 식생활 관리를 위한 기초자료로 제공하고자 하였다. 본 연구결과 전체적으로 영양표시를 인지하는 비율은 91.9%였고, 이들 중 영양표시를 이용하는 청소년은 27.9%로 인지율에 비해 이용률이 낮았다. 아침결식률과 외식빈도, 음주, 흡연, 주관적 건강상태의 경우는 영양표시 이용군과 비이용군별 간에 유의적인 차이는 보이지 않았다. 영양소 섭취량의 경우 무기질인 칼슘, 인, 칼륨 섭취량은 이용군이 비이용군의 섭취량 보다 더 높게 나타났다(p<0.01). 영양표시 이용군에게서 섭취 영양소 중 단백질(p<0.05), 칼슘(p<0.01), 인(p<0.01), 칼륨(p<0.01)의 섭취기준 비율이 비이용군에 비해 높게 나타났다. EQ-5D index로 분석한 건강 관련 삶의 질 점수는 영양표시 이용군은 0.97점, 비이용군은 0.96점으로 영양표시 이용군의 삶의 질 점수가 비이용군 보다 더 높았다(p<0.001). 이상의 연구결과 청소년들의 식생활 개선과 영양표시제 관련 영양교육이 매우 필요하며, 청소년들의 합리적인 식품선택을 도와주고 영양표시 활용도를 높일 수 있는 체계적인 영양 교육이 이루어져야 한다. 따라서 본 연구는 청소년의 올바른 영양표시 이용과 식생활 관리를 위한 영양교육의 기초자료를 마련하는데 유용한 정보로 활용 될 수 있을 것으로 기대된다.