수면 부유 방법에 의한 연초 육묘

洪淳達,石泳善,朴孝澤 충북대학교 엽연초연구소 1999 煙草硏究 Vol.17 No.-

Carbonized rice hull, perlite, and vermiculite were mixed and investigated for the probability of tobacco transplant production by means of plug and transfer float system. These seedling bed materials in condition of float system have gaseous phase ranged from 6% to 13% showing a proper growth of tobacco seedling. However compost media mixed with soil, sand, and compost in condition of float system led to the shortage of respiration in root system by very low proportion of gaseous phase skewing a wicked growth of seedling. Absorption of heat by floating water for the daytime increased rhizosphere temperature in condition of float system during the night and low temperature season resulting in better growth of tobacco seedling. Consequently transplant production of tobacco seedling by float system with mixed materials of carbonized rice hull, perlite, and vermiculite was thought to be desirable method for manufacturing production system of transplant considering the effective management of water, nutrients, and temperature of seedling bed materials.

시설재배 작물의 적정 시비량 결정을 위한 간이 검정법

홍순달,박효택,김기인,한갑동 충북대학교 첨단원예기술개발연구센터 1999 연구보고서 Vol.4 No.-

시설재배 토양의 질산태 질소 간이검정법을 선발하기 위하여 test strip을 이용한 Nitracheck Reflectometer법과 휴대용 비색계를 이용한 Hanna Ion Specific meter법을 실험실 kjeldahl법 및 이온 전극법과 함께 비교 분석하였다. 평가방법의 신뢰도는 NO3-N 함량이 10 mg/kg에서 340 mg/kg으로 분포되는 20개 시설재배 토양에 대하여 표준편차, 변이계수 및 회수율을 비교하였다. 휴대용 비색계법은 낮은 농도와 높은 농도에서 큰 오차범위를 보였으나 Nitracheck Reflectometer법은 두가지 실험실법과 유사한 신뢰도와 회수율을 보였다. 따라서 간편한 분석조작과 짧은 분석시간을 구비한 Nitracheck Reflectometer법은 신뢰성 있는 간이 검정법으로 활용 가능한 것으로 평가되었다. 시설재배 작물의 질소 덧거름 시용량의 결정을 위한 식물체 간이 검정법(SPAD, Minolta 502)을 개발하기 위하여 엽록소 측정치와 토마토의 생산능력 및 토양의 질소공급능력과의 상호관계를 조사하였다. 평가방법은 NO3-N 함량이 55~306 mg kg-1인 6개 토양에 대하여 무비구 토마토의 건물중과 질소 흡수량, 그리고 재배기간 동안의 경시적 엽위별 엽록소 측정치와의 회귀관계로부터 토마토의 생산능력과 질소공급능력에 대한 엽록소의 측정치의 기준을 추정하였다. 토양의 질산태 질소 함량과 무비구 토마토의 건물중 및 질소 흡수량의 상호관계는 유의성 있는 정상관의 곡선적 관계를 보였으며 최대 건물중과 질소 흡수량에 대한 질산태 질소의 함량은 각각 215 mg kg-1과 208 mg kg-1로 추정되었다. 이는 시설재배 배추의 질소 시비량 결정을 위한 질산태 질소의 상한기준 200 mg kg-1의 평가기준과 유사하였다. 토마토 재배기간 동안 엽위별 엽록소 측정치는 정식후 45일째 15매 잎에서 최대를 보인 후 감소되었으며 정식후 45일째 이후 토마토의 엽록소 측정치는 토양의 질소 공급능력에 따라 현저한 차이를 나타냈다. 토마토 잎의 엽록소 측정치는 단위 엽면적당 질소 흡수량과 유의성 있는 정의 상관을 보여 질소 영양진단을 위한 간이 검정법으로 활용 가능성을 보였다. 정식후 40일째 14매엽의 엽록소 측정치는 토양의 질산태 질소, 무비구 토마토의 건물중 및 질소 흡수량과 유의성 있는 정 상관의 곡선적 관계를 보였다. 부비구 토마토의 최대 건물중과 최대 질소 흡수량에 대한 엽록소 측정치의 기준은 각각 57.1로 동일하게 평가되었다. 무비구 토마토의 최대 건물중과 질소 흡수량으로 평가된 엽록소 측정치 57.1에 대한 토양의 질산태 질소 함량은 약 200 mg kg-1로 추정되어 무비구 토마토의 최대 건물중과 질소 흡수량으로 평가된 질산태 질소 기준 208~215 mg kg-1과 비슷하게 평가되었다. 따라서 엽록소 간이검정법은 토양의 질소공급능력을 예측할 수 있는 유효지표로 활용할 수 있는 것으로 생각되었다. To find a rapid determination method for soil nitrate concentration, two methods, "Nitracheck 404" reflectometer(Eijkelkamp, Netherlands) with nitrate test strip and a portable colorimeter "Hanna Ion Specific meter(USA) with a color development reagent, were tested for twenty soils with different nitrate contents ranged between from 10 mg kg-1 to 340 mg kg-1 and compared Standard deviation, coefficient of variability, and recovery of these values with those measured by conventional Kjeldahl distilation method and nitrate electrode method. The nitrate concentration measured by portable colorimeter method was higher in soils with low concentration and lower in soils with high concentration than that measured by conventional methods. However, concentrations measured by nitracheck reflectometer method was showed the similar coefficient of variability and recovery as those by conventional methods for all soil samples. With this result, the Nitracheck reflectometer method was thought to be available for rapid determination of soil nitrate with accuracy, quickness, and simplicity for operating of analysis. To find diagnosing method of nitrogen status in tomato plant for determining optimum application rate of side dress, chlorophyll content were measured by portable chlorophyll meter(SPAD 501, Minolta), and compared it soil nitrogen status. Regression between dry weight, nitrogen accumulation in tomato grown with no fertilizer and chlorophyll content at different stalk positions of tomato were evaluated for 6 soils with different nitrate concentrations ranged between from 55 mg kg-1 to 306 mg kg-1. Soil nitrate concentration was significantly correlated with dry weight and nitrogen accumulation in tomato grown with no fertilizer. And the critical levels of soil nitrate for maximum dry weight and nitrogen accumulation were 215 mg kg-1 and 208 mg kg-1, respectively. These critical levels of soil nitrate were similar to the estimating level (200 mg kg-1) for Chinese cabbage with no fertilizer under the greenhouse. The chlorophyll content of tomato occurred peak at the 15th leaf of stalk position on the 45 days after transplanting and this suggested that before and near the 45 days after transplanting is the critical time for chlorophyll test of tomato for diagnosing nitrogen status. And the chlorophyll content of tomato grown with no fertilizer after the critical time was affected by the level of soil nitrate concentration, which suggested that chlorophyll content after 45 days after transplanting reflect the soil nitrogen supplying capacity. The chlorophyll content of tomato leave was significantly correlated with amount of nitrogen per unit area of leave. It was suggested that chlorophyll content is useful for nitrogen diagnosis of plant. And the chlorophyll content of the 14th leaf at the 40 days after transplanting was significantly correlated with soil nitrate status, dry weight of tomato and nitrogen accumulation in tomato plant grown with no fertilizer. Chlorophyll content for maximum dry weight and nitrogen accumulation in tomato plant grown with no fertilizer were 57.1 mg kg-1 that represent soil nitrate as 200 mg kg-1. This critical level of soil nitrate was similar to those of 215 mg kg-1 and 208 mg kg-1 estimated by dry weight and nitrogen accumulation in tomato plant grown with no fertilizer, respectively. Consequently, rapid test of chlorophyll would be available for predicting the nitrogen supplying capacity of tomato.

Capsaicin 사전 투여에 의한 흰쥐의 공격성 감소 및 자율적 체온조절의 결손

박순권,홍승길,나흥식,김현택 한국심리학회 한국심리학회지 생물 및 생리 Vol.7 No.1

capsaicin 사전 처치가 흰쥐의 공격성과 체온조절에 미치는 영향을 알아보았다. 생후 6주경에 capsaicin을 피하주사하였고, 완전히 성숙한 후에 공격성 및 체온조절 기능을 검사하였다. 실험 1의 공격성 검사 결과 capsaicin 처치동물들의 공격성은 통제동물보다 낮았는데, 이것은 선행 연구의 결과와 상반된다. 체온조절 기능을 알아본 실험 2에서는 capsaicin 처치동물들이 37℃ 및 40℃ 조건에서 과체온과 빠른 체온증가를 보여주었다. 이것은 출생 직후 또는 성숙한 후에 약물을 투여한 선행연구들과 일치되는 결과이다. 따라서 capsaicin이 체온조절에 미치는 영향은 투여 시기와 무관한 것 같다. 논의에서는 본 연구의 두 가지 결과를 시상하부와 관련시켜 해석하였다. The present study was designed to examine effects of capsaicin administration on aggressive behaviors and autonomic thermoregulation in rats. In six-week-old rat, capsaicin was injected subcutaneously on 4 consecutive days in increasing doses(20㎎/㎏, 30㎎/㎏, 30㎎/㎏, 50㎎/㎏) to total of 150㎎/㎏ of the drug. The controls were treated in the same way with vehicle alone. Two experments began six or eight weeks after the treatment. In experiment 1, isolation-induced agressive behaviors, scored a 10-min session in the dyadic situation, were significantly decreased by capsaicin pretreatment. This result was not in accord with the previous findings. In experiment 2, body temperature of the capsaicin-treated rats increased more than the control's at two amibient temperatures studied(37℃ and 40℃). Our result concerning thermoregulation supports the preceding studies that applied to the capsaicin-treated animals as neonate or adult. Thus, it is likely that the effect of capsaicin treatment on thermoregulation has nothing to do with the age of capsaicin injection. The capsaicin effects from this study were compared with hypothalamic lesion effects in the discussion part.

Capsaicin이 성숙한 흰쥐의 통각반응과 open-field 행동에 미치는 영향

박순권,김현택,나흥식,홍승길 한국심리학회 한국심리학회지 생물 및 생리 Vol.7 No.1

성숙한 흰쥐에게 전신계로 투여한 capsaicin(150㎎/㎏)이 개방장(open-field)행동과 통각반응의 역치 및 반응잠재기에 미치는 효과를 알아보았다. 첫째, open-field행동에는 capsaicin의 효과가 관찰되지 않았는데 이것은 capsaicin이 흰쥐의 정서반응성과 운동기능에는 영향을 미치지 않음을 의미하는 것이다. 둘째, capsaicin 투여에 의해 열자극에 대한 앞발 및 뒷발핥기의 역치는 변화되지 않았으나, 뛰어오르기의 역치는 증가되었다. 또한 역치 이상의 열자극에 대한 뒷발핥기 반응의 잠재기도 capsaicin 투여에 의해 증가되었다. 이 결과는 비교적 약한 열자극에 대한 적응반응에는 capsaicin이 영향을 미치지 않으나 강한 열자극에 대한 대처반응에는 영향을 미치는 것으로 해석된다. We investigated the effects of capsaicin(s.c. 150㎎/㎏) on the open-field behaviors and the thresholds and latency of nociceptive responses in adult rats. Results are as follows. 1) Capsaicin did not affect open-field behaviors. It hints that capsaicin did not alter the emotionality and motor function of rats. 2) Whereas the threshold of jumping was elevated, those of fore and hind paw licking were not in animals treated with capsaicin. Capsaicin also enhanced hind paw licking latency to thermal stimulus over thershold in hot plate test. These results suggest that capsaicin affects the coping reaction to strong thermal stimulus, but not adaptive reaction to mild stimulus, in adult rats.

Electrophoretic Mobility to Monitor Protein-Surfacant Interactions

Hong, Soon-Taek The Korean Society of Food Science and Nutrition 1998 Preventive Nutrition and Food Science Vol.3 No.2

Protein -surfactant interactions have been investigate by measuring ζ-potential of $\beta$-lactoglobulin-coated emulsion droplets and $\beta$-lactoglobulin in solution in the rpesenceof surfactant, with particular emphasis on the effect of protein heat treatment(7$0^{\circ}C$, 30min). When ionic surfactant (SDS or DATEM) is added to the protein solution, the ζ-potential of the mixture is found to increase with increasing surfactant concentration, indicating surfactant binding to the protein molecules. For heat-denatured protein,it has been observed that the ζ-potential tends to be lower than that of the native protein. The effect of surfactant on emulsions is rather complicated .With SDS, small amounts of surfactant addition induce a sharp increase in zeta potential arising from the specific interaction of surfactant with protein. With further surfacant addition, there is a gradual reductio in the ζ-potential, presumably caused by the displacement of adsorped protein (and protein-surfactant complex) from the emulsion droplet surfac by the excess of SDS molecules. At even higher surfactant concentrations, the measured zeta potential appears to increase slightly, possibly due to the formation of a surfactant measured zeta potential appears to increase slightly, possibly due to the formation of surfactant micellar structure at the oil droplet surface. This behaviour contrastswith the results of the corresponding systems containing the anionic emulsifier DATEM, in which the ζ-potential of the system is found to increase continuously with R, particularly at very low surfactant concentration. Overall, such behaviour is consisten with a combination of complexation and competitive displacement between surfactant and protein occurring at the oil-water interface. In addition, it has also been found that above the CMC, there is a time-dependent increase in the negative ζ-potential of emulsion droplets in solutions of SDS, possibly due to the solublization of oil droplets into surfactant micelles in the aqueous bulk phase.

Orthokinetic Stability of $\beta$-Lactoglubulin-Stabilized Emulsions : Effects of Protein Heat Treatment and Surfactant Addition

Hong, Soon-Taek The Korean Society of Food Science and Nutrition 1998 Preventive Nutrition and Food Science Vol.3 No.2

Effects of protein heat treatment and surfactant additionoo the orthokindetic stability of $\beta$-lactoglobulin-stabilized emulsions have been investigated under turbulent flow conditions. In studies on protein-stabilized emulsions, samples which had been subjected to heat treatment(i.e. the protein solution orthe emulsion) have been found to be more prone to orthokinetic coalescene than the untreated ones. The emulsions stabilized with protein heated above the denaturation temperature(i.e. 7$0^{\circ}C$) showed the bigger initial average droplet size, which resulted in an increased orthokinetic coalescenece rate. The storage of the protein-stabilized emulsion at high temperature prior to the shearing experiment also made the emulsion less stable in the shear field. Interestingly. the addition of DATEM has been found to produce a substantial increase in orthokinetic stability of the heat-denatured protein-stabilized emulsion system, although Tween 20 is the opposite case.

Electrophoretic Mobility to Monitor Protein - Surfactant Interactions

Soon-Taek Hong 한국식품영양과학회 1998 Preventive Nutrition and Food Science Vol.3 No.2

Protein-surfactant interactions have been investigated by measuring ξ-potential of β-lactoglobulin-coated emulsion droplets and β-lactoglobulin in solution in the presence of surfactant, with particular emphasis on the effect of protein heat treatment (70℃, 30 min). When ionic surfactant (SDS or DATEM) is added to the protein solution, the ξ-potential of the mixture is found to increase with increasing surfactant concentration, indicating surfactant binding to the protein molecules. For heat-denatured protein, it has been observed that the ξ-potential tends to be lower than that of the native protein. The effect of surfactant on emulsions is rather complicated. With SDS, small amounts of surfactant addition induce a sharp increase in zeta potential arising from the specific interaction of surfactant with protein. With further surfactant addition, there is a gradual reduction in the ξ-potential, presumably caused by the displacement of adsorbed protein (and protein-surfactant complex) from the emulsion droplet surface by the excess of SDS molecules. At even higher surfactant concentrations, the measured zeta potential appears to increase slightly, possibly due to the formation of a surfactant micellar structure at the oil droplet surface. This behaviour contrasts with the results of the corresponding systems containing the anionic emulsifier DATEM, in which the ξ-potential of the system is found to increase continuously with R, particularly at very low surfactant concentration. Overall, such behaviour is consistent with a combination of complexation and competitive displacement between surfactant and protein occurring at the oil-water interface. In addition, it has also been found that above the CMC, there is a time-dependent increase in the negative ξ-potential of emulsion droplets in solutions of SDS, possibly due to the solublization of oil droplets into surfactant micelles in the aqueous bulk phase.

Surface Shear Viscosity as Affected by Protein-Surfactant Interactions

Hong, Soon-Taek 한국산업식품공학회 2003 산업 식품공학 Vol.7 No.3

Surface shear rheology of adsorbed β-lactoglobulin film (bulk protein concentration 2×10^(-3) wt% containing small-molecule surfactant (ionic water-soluble SDS or noniconic oil-soluble Sp-80) has been investigated using a two-dimensional Couette-type viscometer. The effect of surfactant concentration, pH (5.5, 6, 7, 8.5) and heat treatment (70℃, 1 h) have been evaluated by measurements of changes in the apparent surface shear viscosity. With the SDS addition, the typical shear thinning behaviour of the adsorbed protein film in observed, which is more pronounced at the interface where less amounts of the ionic surfactants are associated. The higher pH and heat treatment also result in the pronounced shear thinning character of the protein film. The presence of oil-soluble surfactant influences on the surface shear viscosity. At low surfactant concentrations (R≤12), it is higher than that of the pure β-lactoglobulin film but the opposite is the case at high surfactant concentrations (R≥16). This may suggest the co-operative and competitive adsorption of the protein at the oil-water interface.

Surface Shear Viscosity as Affected by Protein-Surfactant Interactions

Soon-Taek Hong 한국산업식품공학회 2003 산업 식품공학 Vol.7 No.3

Orthokinetic Stability of β - Lactoglobulin - Stabilized Emulsions : Effects of Protein Heat Treatment and Surfactant Addition

Soon-Taek Hong 한국식품영양과학회 1998 Preventive Nutrition and Food Science Vol.3 No.2

Effects of protein heat treatment and surfactant addition on the orthokinetic stability of β-lactoglobulin-stabilized emulsions have been investigated under turbulent flow conditions. In studies on protein-stabilized emulsions, samples which had been subjected to heat treatment (i.e., the protein solution or the emulsion) have been found to be more prone to orthokinetic coalescence than the untreated ones. The emulsions stabilized with protein heated above the denaturation temperature (i.e., 70℃) showed the bigger initial average droplet size, which resulted in an increased orthokinetic coalescence rate. The storage of the protein-stabilized emulsion at high temperature prior to the shearing experiment also made the emulsion less stable in the shear field. Interestingly, the addition of DATEM has been found to produce a substantial increase in orthokinetic stability of the heat-denatured protein-stabilized emulsion system, although Tween 20 is the opposite case.