• KSBB Journal
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• v.22 no.5
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• pp.345-350
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• 2007

Phosphosugars are found in all living organisms and are commercially valuable compounds with possible applications in the development of a wide range of specialty chemicals and medicines. In carbohydrate metabolism, fructose 6-phosphate (F6P) is an essential intermediate formed by phosphorylation of 6' position of fructose in glycolysis, gluconeogenesis, pentose phosphate pathway and Calvin cycle. In glycolysis, F6P lies within the glycolysis metabolic pathway and is produced by isomerisation of glucose 6-phosphate. For large-scale production, F6P could be produced from starch using many enzymes such as pullulanase, starch phosphorylase, isomerase and mutase. In enzymatic reactions carried out at high temperatures, the solubility of starch is increased and microbial contamination is minimized. Thus, thermophile-derived enzymes are preferred over mesophile-derived enzymes for industrial applications using starch. Recently, we reported the production of glucose 1-phosphate (G1P) from starch by Thermus caldophilus GK24 enzymes. Here we report the production of F6P from starch through three steps; from starch to glucose 1-phosphate (glucan phosphorylase, GP), then glucose 6-phosphate (phosphoglucomutase, GM) and then F6P (phosphoglucoisomerase, GI). Using 200 L of 1.2% soluble starch solution in potassium phosphate buffer, 1,253 g of G1P were produced. Then, 30% yields of F6P were attained at the optimum reaction conditions of GM : G1 (1 : 2.3), 63.5$^{\circ}C$, and pH 6.85. The optimum conditions were found by response surface methodology and the theoretical values were confirmed by the experiments. The optimum starch concentrations were 20 g/L under the given conditions.

• Journal of Life Science
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• v.29 no.12
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• pp.1364-1370
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• 2019

The anti-oxidant activity, sinigrin content, and sensory evaluation of frying batter treated with Dolsan leaf mustard powder (DLMP) were investigated. These endpoints were measured in the control sample (batter without DLMP) and seven other batters with the addition of DLMP in the following quantities: 0.03 g (S-1), 0.02 g (S-2), 0.06 g (S-3), and 0.3 g (S-4, S-5, S-6, and S-7 with different amounts of red pepper powder). The acid value (AV) and peroxide value (POV) were low in the S-4 and S-5 batters; the total polyphenol content was 190.97 mg GAE/g in the control sample and 721.17 mg GAE/g in S-4; and the total flavonoid content of S-6 was 67.82 mg QE/g which was higher than that of the control sample. The anti-oxidant activity was measured by EDA, ABTS, and FRAP assays and was seen to rise as the amount of DLMP increased. Moreover, sinigrin content was higher in S-4, S-5, S-6, and S-7 than in the control, S-1, S-2, and S-3, and there were no significant differences among S-4 to S-7 when just 0.3 g of DLMP was added. Sensory evaluation showed that color, flavor, taste, texture, and overall acceptability values were significantly higher in S-4 and S-5, and that there was no significant difference across the samples. The addition of DLMP is therefore expected to increase the anti-oxidant activity of frying batter which would be effective in improving the storage and quality of the product.

• Information and Communications Magazine
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• v.33 no.6
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• pp.27-32
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• 2016

본고에서는 5G 포럼 네트워크 위원회에서 진행하고 있는 기술백서의 내용을 중심으로 5G 네트워크에 대한 고찰을 통해서 다가올 5G 네트워크에 대한 진화를 예측해 보고자 한다. 5G, 즉 IMT-2020은 홀로그램, 8K UHD와 같은 진화된 비디오 서비스를 안정적으로 사용하기 위하여 기존 대비 20배 증가된 20Gbps의 최고 전송 속도, 기존 대비 10배 향상된 100Mbps 이상의 이용자 체감 전송 속도 제공을 기본 목표로 하고 있다. 이런 5G 네트워크의 요구 사항을 기능, 구조, 운영 관점에서 살펴보고, 코어네트워크에서 필요한 요구 사항과 고려되고 있는 기술에 대한 고찰을 통해 5G에서의 코어 네트워크에 대한 이해를 돕고자 한다.

• Review of KIISC
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• v.31 no.6
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• pp.37-40
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• 2021

미국, 중국 등에 이어 국내에서도 KT에서 2021년 7월 5G 단독모드(StandAlone)를 상용화 하였다. 5G 비단독모드(Non-StandAlone)에서는 다년간 사용되었던 기존 LTE(Long Term Evolution) 망의 장비를 재활용하기 때문에 신규 장비의 도입은 5G 기지국으로 제한된다. 그러나 5G 단독모드에서는 새롭게 정의된 5G 장비들을 사용하기 때문에 이에 대한 위협 분석과 보안 기능의 정의에 따라 각 장비에 보안의 구현이 제대로 되어 있는지 검증하는 절차가 요구된다. 이러한 환경에서 본 논문은 5G 단독모드 기기의 보안 인증 현황을 제공하고자 한다.

• Korean Journal of Community Nutrition
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• v.2 no.3
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• pp.281-293
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• 1997

Dietary fiber(DF) intake of teenagers was estimated and the major food sources of fiber were analyzed using three-day food records and data from 365 middle school students in urban, rural and fishing areas. Mean dwily DF intake of males was 9.2$\pm$3.9g in urban, 10.4$\pm$5.4g in rural, and 7.9$\pm$4.0g in fishing areas and the intake of female was 10.6$\pm$5.1g in urban, 10.6$\pm$5.2g in rural, and 7.7$\pm$3.3g in fishing areas. When related to energy intake, female consumed more DF(5.7$\pm$2.5g/1000㎉, 7.0$\pm$3.5g/1000㎉, 4.6$\pm$2.2g/1000㎉, in urban, and rural, fishing areas respectively) than males(4.2$\pm$1.3g/1000㎉, 4.6$\pm$1.5g/1000㎉, 4.4$\pm$2.0g/1000㎉ in urban, rural, fishing respectively). Mean crude fiber(CF) intake of males was 4.1$\pm$1.7g, 4.5$\pm$2.4g, 3.7$\pm$2.4g, and female's intake was 4.7$\pm$1.9g, 4.8$\pm$2.2g, 3.7$\pm$1.9g in urban, rural, and fishing areas respectively. The mean DF : CF ratio for the subjects was 2.2-2.6, indicating that the DF intake is 2-3 times that of CF intakes. The intakes of the two measures of fiber were highly correlated(r=0.7781) . The major food sources for DF were cereals, vegetables and fruits and the percentage contributions of the food groups to the DF intake were 27-37$\%$, 22-30$\%$, and 11.5-19.7$\%$ respectively. The present study indicates that the DF intake of teenagers is considerably lower than the recommended level and they need to consume more DF than that indicated by the present levels. The importance of nutrition education on health and dietary pattern should also be emphasized among teenagers.

• The Korean Journal of Soil Zoology
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• v.5 no.2
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• pp.165-168
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• 2000

The earthworm was investigated for knowing about that he inhabits in grassland, orchard field, organic farming land, greenhouse land, and ordinary farming land according to use of upland. The earthworm lives all in grassland and orchard field where was investigated, in 6 among 8 sites of organic farming land, in 5 among 12 sites of greenhouse land, in 5 among 25 sites of ordinary farming land. The earthworms that were shown are the Lumbricidae and the Megascolecidae. The number of the earthworm was 14 in orchard field, 12 in grassland, 10 in organic farming land, 7 in greenhouse land and 3 in ordinary farming land. The weight of the earthworms was declined in order of 12.3 g in orchard field, 11.6 g in organic farming land, 10.6 g in grassland, 4.2 g in greenhouse land and 2.9 g/0.25 m$^2$in ordinary farming land. If the water content of soil is not below 5% or over 35%, earthworm was no problem to live in. It was examined that the earthworm could live if pH values was not just strong acid or alkal. And if the organic matter is below 1%, the earthworm do not live but move another place.

• Korean Journal of Food Science and Technology
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• v.48 no.1
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• pp.36-41
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• 2016

In this study, the effects of intense pulsed light (IPL) treatment on microbial inactivation and quality in rapeseed sprouts were investigated. Untreated rapeseed sprouts exhibit a high level of total aerobic bacteria (TAB) ($1.2{\times}10^7CFU/g$), coliform bacteria (coliform) ($3.3{\times}10^6CFU/g$), and pathogenic E. coli (PE) ($2.1{\times}10^5CFU/g$). The microorganisms found on rapeseed sprouts decreased with exposure to increasing light intensity and treatment time. The greatest reduction in microbial content was observed with a treatment of 1000 V, 5 pps for 10 min, where TAB, coliform, and PE levels decreased to 1.0 log CFU/g, 1.6 log CFU/g, and 1.8 log CFU/g, respectively. In agreement with these data, the microbial inactivation rate increased with the increase in the distance between the light source and the samples during IPL treatment. After IPL treatment of rapeseed sprouts, water content and vitamin C content decreased.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.7
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• pp.983-987
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• 2003

Malpura and Kheri ewes (76) in their late gestation, weighing $34.40{\pm}0.95kg$ were randomly selected and divided into 4 groups of 19 each (G1, G2, G3 and G4). Ewes in all the groups were grazed on natural rangeland from 07.00 h to 18.00 h. Ewes in G1were maintained on sole grazing while ewes in G2, G3 and G4, in addition to grazing received concentrate mixture at the rate of 1% of their body weight during late gestation, early lactation and entire last quarter of pregnancy to early quarter of lactation, respectively. The herbage yield of the community rangeland was 0.82 metric ton dry matter/hectare. The diet consisted of (%) Guar (Cyamopsis tetragonoloba) bhusa, (59.2), Babool pods and leaves (17.2), Bajra (Pennisetum typhoides) stubbles (8.8), Doob (5.3), Aak (4.2) and others (5.3). The nutrient intake and its digestibility were higher (p<0.01) in G2, G3 and G4 as compared to G1 because of concentrate supplementation. The intakes of DM ($g/kg\;W{^0.75}$), DCP ($g/kg\;W{^0.75}$) and ME ($MJ/kg\;W{^0.75}$) were 56.7, 5.3 and 0.83; 82.7, 12.2 and 1.16; 82.7, 12.1 and 1.17 and 83.1, 12.3 and 1.18 in G1, G2, G3 and G4, respectively. The per cent digestibility of DM, OM, CP, NDF, ADF and cellulose was 57.9, 68.8, 68.7, 52.3, 37.5 and 68.4; 67.6, 76.1, 82.3, 60.6, 44.5 and 73.4; 67.6, 76.1, 81.5, 60.6, 44.8 and 74.5 and 67.6, 76.1, 82.3, 60.6, 44.7 and 73.3 in G1, G2, G3 and G4, respectively. The nutrient intake of G2, G3 and G4 ewes was sufficient to meet their requirements. The ewes raised on sole grazing lost weight at lambing in comparison to advanced pregnancy. However, ewes raised on supplementary feeding gained 1.9-2.5 kg at lambing. The birth weight of lambs in G2 (3.92) and G4 (4.07) was higher (p<0.01) than G1 (2.98), where as in G1 and G3 it was similar. The weight of lambs at 15, 45 and 60 days of age were higher in G2, G3 and G4 than in G1. Similarly, the average daily gain (ADG) after 60 days was also higher in G2, G3 and G4 than in G1. The milk-yield of lactating ewes in G2, G3 and G4 increased up to 150-250 g per day in comparison to G1. The birth weight, weight at 15, 30, 45 and 60 days, weight gain and ADG at 30 or 60 days was similar both in male and female lambs. It is concluded from this study that the biomass yield of the community rangeland is low and insufficient to meet the nutrient requirements of ewes during late gestation and early lactation. Therefore, it is recommended concentrate supplementation at the rate of 1% of body weight to ewes during these critical stages to enhance their production performance, general condition as well as birth weight and growth rate of lambs.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2003.07a
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• pp.84-84
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• 2003

고분자 키토산(분자량 약 800,000)을 농도별(0%, 0.1%, 0.2%, 0.3%)로 김치를 제조하여, pH, 적정산도, 총균수, 젖산균 수, 대장균군 수 및 관능검사를 조사한 결과는 다음과 같이 나타났다. 1. 키토산 무첨가 김치는 발효 후 6일경에 pH가 초기 5.4에서 4.1로 급격히 떨어졌으며 그 후부터는 천천히 떨어져 발효 후 약 15일 경과 후에는 3.9로 나타났다. 그러나 0.1%, 0.2% 및 0.3% 고분자 키토산을 첨가한 김치에서는 초기 pH 5.38, 5.30 및 5.28에서 6일경에는 pH가 0.1%, 0.2% 및 0.3% 고분자 키토산에서 4.23, 4.34 및 4.47로 각각 나타났다. 15일 경과 후에는 0.1% 고분자 키토산 김치는 키토산 무첨가 김치와 거의 같은 pH인 3.9로 나타났으나 0.2%와 0.3% 고분자 키토산 김치의 pH는 3.90보다 높은 4.10, 4.10으로 각각 나타났다. 2. 각 김치 종류별 적정산도를 측정한 결과는 발효초기에 모든 구가 0.72%로 나타났으며, 발효 후 6일 경에서는 키토산 무첨가, 0.1%, 0.2% 및 0.3% 고분자 키토산 김치의 적정산도는 각각 2.16%, 2.00%, 1.70% 및 1.30%로 나타났다. 그리고 15일 경과 후에는 키토산 무첨가 김치의 적정산도가 2.25%이였으나 0.1%, 0.2% 및 0.3% 고분자 키토산 김치는 각각 2.26%, 2.24 및 2.22%로 나타났다. 3. 발효가 진행 중에 총균수를 측정한 결과 시간과 더불어 총균수가 모든 구에 있어서 서서히 증가하였고 발효초기의 모든 김치구의 총균수는 2.5X105∼5.4X106 cfu/g 범위였으며, 김치 맛이 들기 시작한 6일경에서의 각 구별 총균수는 키토산 무첨가 김치가 2.4X109 cfu/g이였구 0.1%, 0.2% 및 0.3% 고분자 키토산 김치의 총균수는 각각 1.2X109 cfu/g, 4.0X108 cfu/g 및 1.1X107 cfu/g으로 나타났다. 그리고 김치가 완전히 익은 15일 후에는 무첨가 김치, 0.1%, 0.2% 및 0.3% 고분자 키토산 김치의 총균수는 5.4X107 cfu/g, 3.3X107 cfu/g, 1.8X108cfu/g 및 4.2X108 cfu/g로 나타났다. 4. 발효가 진행 중에 젖산균 수를 측정한 결과 시간과 더불어 젖산균 수가 모든 구에 있어서 서서히 증가하였으며, 발효초기의 모든 김치구의 젖산균 수는 2.0X104∼2.7X106 cfu/g 범위였으며 김치 맛이 들기 시작한 6일경에서의 각 구별 젖산균 수는 키토산 무첨가 김치가 3.2X108 cfu/g이었고, 0.1%, 0.2% 및 0.3% 고분자 키토산 김치의 젖산균 수는 각각 1.6X108 cfu/g, 13X108 cfu/g 및 9.6X107 cfu/g으로 나타났다. 그리고 김치가 완전히 익은 15일 후에는 무첨가 김치, 0.1%, 0.2% 및 0.3% 고분자 키토산 김치의 젖산균 수는 5.4X107 cfu/g, 3.3X107 cfu/g, 8.6X106 cfu/g 및 2.6X106 cfu/g로 나타났다. 5. 발효가 진행 중에 대장균 군 수가 시간과 더불어 대장균군 수가 모든 구에 있어서 6일까지는 서서히 증가하다가 그 후부터는 대장균 군 수가 감소하였다. 즉, 발효초기에는 모든 구가 2.0X104∼4.0X105 cfu/g이었고, 6일 경에는 8.9X104∼4.5X105 cfu/g로 약간 증가하였으며 15일후에는 키토산 무첨가 김치가 2.0X102 cfu/g이었으며, 0.1%, 0.2% 및 0.3% 고분자 키토산 김치의 대장균군 수는 각각 2.0X102 cfu/g, 1.1X102 cfu/g 및 4.0X101 cfu/g로 점점 감소하였다. 6. 관능검사 결과는 키토산 무첨가 김치와 0.1% 첨가 김치는 유사한 선호도를 나타내어 0.1% 첨가 김치가 기능성과 보존성을 높여줄 뿐만 아니라 선호도도 높은 것으로 나타났다.

• Korean journal of food and cookery science
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• v.22 no.2 s.92
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• pp.164-172
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• 2006

The purpose of this study was to find the optimal mixing condition of three different amounts of pine leaf powder, butter and sugar for preparation of pine leaf cookies. The optimum mixing condition for pine leaf cookies was optimized by response surface methodology The optimum mixing rates of pine leaf powder, butter and sugar were 8.6 g, 252.8 g and 154.1 g for color, 8.4 g, 240.7 g and 149.8 g for appearance, 8.8 g, 246.5 g and 154.7 g for flavor and 10.9 g, 277.1 g and 134.6 g for texture respectively. The optimum mixture ratio which fulfilled all items was pine leaf powder 9.4 g, butter 270.5 g and sugar 141 g.