http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
제조조건에 따른 키토산의 이화학적 특성 및 Streptococcus mutans 에 대한 항미생물 효과
김용진(Y. J. Kim),장은정(E. J. Chang),이연형(Y. H. Lee),오훈일(H. I. Oh),조도현(D. H. Jo) 한국키틴키토산학회 2001 한국키틴키토산학회지 Vol.6 No.3
N/A Four kinds of chitosan were prepared by treating crude chitin with various NaOH concentrations. The physicochemical properties and antimicrobial activity of the chitosan against Streptococcus mutans, a primary causative bacterium of dental caries, were investigated. Moisture, crude ash and nitrogen contents of the prepared chitosans were ranged from 5.86-6.72%, 0.46-1.12% and 6.53-7.Iff), respectively. The molecular weights of chitosan-45,-50,-55 and -60 were determined as 59,000,33,000,26,000 and 12,000. respectively. Chitosans prepared with higher concentrations of NaOH solution showed a lower molecular weight. The degree of deacetylation of chitin and various chitosans determined by IR spectrum were 45% and 75-87%, respectively. Chitin had higher water holding and fat binding capacities than the chitosans. However, there were no significant differences among the four chitosans. In dye binding, chitin had a dye binding capacity of 9.32±1.6 mg/g sample, but chitosans except chitosan-45, almost did not bind the dye. It was asssumed that NH2 functional group in the chitosans was removed along with the acetyl group due to the strong deacetylation conditions. The addition of chitosan caused an initial rapid decrease in the population of S. mutans, which was followed by a delayed recovery. The viable cell counts of .S. mutans incubated with 40 ppm chitosan-50(M.W.33,000) were reduced dramatically and S. mutans was not detected after 8h. These results indicate that chitosan can be used for oral care products as anticaries agents.
한범구(B . K . Han),문종국(J . K . Moon),조도현(D . H . Jo),김새봄(S . B . Kim) 한국키틴키토산학회 2001 한국키틴키토산학회지 Vol.6 No.1
키토산용액의 유변학적 특성은 키토산용액의 산업적 이용에 매우 중요한 인자이다 본 실험에서는 다양한 유기산에 키토산을 용해시킨 후에 점도를 측정하였다. 상온에서의 점도감소는 개미산에서 가장 낮았고 부칠 산에서 가장 켰다. 유기산용매에서의 키토산 용액의 점도는 유기산의 탄소 수와 비례하였으나 개미산은 예외로 초산보다 높았다. 한편 전단 속도7 sec-1 까지 뉴톤 흐름을 나타냈으나 초산의 경우는 전단 속도 80 sec-1까지 뉴톤 흐름을 나타냈다. 산이나 염기를 사용하여 키토산 용액의 pH를 조절하면 pH조절 전에 비하여 점도가 감소하였다. The rheological property of chitosan solution is an important factor for the industrial application. We investigated the viscosity of chitosan solution in different organic solvents. The decrease in viscosity during storage at 25℃ was lowest in formic acid and highest in butyric acid. The viscosity of chitosan solution in different organic acids was found to have a positive correlation with the carbon number in the organic acids, except formic acid. Chitosan solutions dissolved in the other organic acid, excepts acetic acid, showed Newtonian behavior up to 7 sec-1shear rate, while that in acetlc acid was 80 sec-1. When the pH of this solution was adjusted with HCI or NaOH, the viscosity decreased. In order to make a stable chitosan solution with organic solvent and at a given pH, it seems necessary to store more than 4 days at room temperature before use.
조도현,이춘영,김호,박연희,이양희 한국농화학회 1980 Applied Biological Chemistry (Appl Biol Chem) Vol.23 No.2
The flavor constituents of Korean Milgam were extracted with a nitrogen gas stream under partial vacuum and identified by gas liquid chromatography. By employing the extraction coefficient, it was possible to determine the concentration of components in Milgam as well as in the extracts. Among 53 GLC peaks, 26 components were identified. Ethanol was the most abundant component (140ppm), followed by limonene (120ppm). These two were the most important flavor constituents.
조도현,이춘영,전형원 한국농화학회 1971 Applied Biological Chemistry (Appl Biol Chem) Vol.14 No.3
The electrophoretic patterns of the thin and thick layers of EWP were observed and the densitometry was conducted. 1. Most characteristic were the patterns of both layers at 7-day incubation compared with those of fresh stage. 2. After 15 days the patterns of both layers were almost same. 3. The ratio of some components of the fresh EWP is in a good accordance with the other wisely measured data.
Indole acetic acid 와 Abscisic acid 가 핵산과 RNase 에 미치는 영향에 관하여
조도현,이춘영 한국농화학회 1972 Applied Biological Chemistry (Appl Biol Chem) Vol.15 No.3
Wheat coleoptile sections were treated with either 1.5×10^(-5) M ABA or 5×10^(-5) M IAA in vitro, the results may be summarized as follows, 1. The treatmert of IAA decreased the level of high molecular weight RNA F2 and F3 but that with ABA increased the F4 level. 2. IAA caused an increased activity of G2 isozyme, while ABA suppressed the activity of G3 isozyme. 3. The results may suggest that there may exist common effects of IAA and ABA on RNA and RNase. 4. The latent RNase activity caused by SH blocking reagent (p-hydroxymercury benzoate, Pb et al) was not observed.