Growing evidence indicates that oxidized low density Iipoprotein (LDL) may promote atherogenesis. Therefore, inhibition of LDL oxidation may impede this process. The effect of chitin sulfate on the susceptibility of human low density lipoprotein (LDL) to macrophages-induced oxidation was investigated by monitoring a thiobarbituric acid reactive substance (TBARS). Chitin sulfate inhibited LDL oxidation by macro phages in a dose dependent manner, with a 50-100μM, as assessed by TBARS assay. Chitin sulfate, at 100 μM, almost completely inhibited the macrophage-induced increase in electrophoretic mobility of LDL. Also, chitin sulfate almost completely inhibit O₂^- at concentration of 100 μM. These observations suggest that chitin sulfate might be an effective in prevention of atherosclerosis.

In spite of various applications of chitin derivatives from waste marine sources, commercial use of chitin has been limited due to resistance to chemicals and the absense of proper solvents. We prepared chitin through decalcification, bleaching and deproteination from protunus trituberculatus shells by the application of Hackman's method. Structural and chemical properties of chitin were investigated to have proper specific surface area and particle size by IR, BET and PSA. The amount of absorbed water of chitin reached equilibrium by stirring about 15 minutes. The amount of absored water of the prepared chitin were large than the commercial chitin. When prepared chitin tested on dyeing wastewater, they showed better treatment efficiency in COD, suspended solid, and color tests than the commercial chitin. The adsorption capacity increased with decreasing particle size for the prepared chitin. Treatment efficiency for color was increased as the sitirring rate increased. Results show the possibility of the prepared chitin from waste marine sources as a treatment system for dyeing wastewater.

수산계 폐기물로부터 chitin 유도체의 다양한 응용에도 불구하고 chitin의 상업적 이용은 적절한 용매의 부재와 화학적 저항성으로 인하여 제한적으로 이용되었다. 그러므로 Mima의 방법을 응요하여 NaOH 농도, 반응시간, 온도 등을 조절하여 탈아세틸화반응에 의한 다양한 점도가 다른 chitosan을 제조하였으며, 2종의 가교제를 이용하여 가교결합에 의한 결정성을 증가시킨 가교 chitosan을 제조하였다. 제조한 점도가 다른 chitosan과 가교 chitosan유도체를 다양한 분석기기를 이용하여 측정하였다. chitosan을 제조시 반응시간을 높이거나 반응온도를 높이면 탈아세틸화는 높아지나 분자사슬의 크기, 즉 점도와 분자량은 감소하였다. 반응온도, 반응시간과 알칼리농도에 따라 활용분야에 맞는 chitosan을 제조할 수 있다.

Chitin/chitosan be known as biodegradable natural polymer. However, commercial use of chitin has been limited due to highly resistance to chemicals and the absense of proper solvents. Therefore, we was studied that chitin was prepared by the application of Hackman's method from Protunus trituberculatus shells. And another viscosity chitosan were prepared from chitin which were deacetylated under various concentration of alkali, reaction time and temperature by the application of Mima's method. And crosslinked chitin/chitosan was preparaed from chitin/chitosan with crosslink agent followed by crosslinkage. The major parameters for chitosan manufacturing methods were found to be concentration of alkali solution, reaction time and temperature etc. The effects of these parameters on chitin, another viscosity(molecular weight) chitosan and crosslinked chitin/chitosan were investigated by various analysis apparatus.

키틴합성저해제인 diflubenzuron, triflumuron, chlorfluazuron을 갈색거처리와 유충과 번데기에 처리하여 효력검정법을 개발하였다. 유충에 대한 처리는 국소처리와 독먹이처리를 행하였고, 번데기에 대하요 용체침적처리와 미량주사처리를 행하였다. 유충에 대한 10 국소처리와 번데기에 대한 100ppm 용체 침적처리 결과 세약제 모두 유충 및 번덱의 발육에 아무런 영향을 주지 않았다. 유충에 대한 독먹이 처리에 있어서의 {{{{ { LC}_{ 50} }}}}값은 diflubenzuron 11.3, triflumuron 42.7, chlorfluazuron 6.2ppm이었다. 번데기에 대한 미량주사처리에서는 diflubenzuron 0.053, triflumuron 0.230, chlorfluazuron 0.340 /pupa의 {{{{ { LC}_{ 50} }}}}값을 나타내었다.

Chitin was isolated from crab shells by modified Hackman's method, which was treated again with aqueous sodium hydroxide solution to give alkali chitin(sodium alkoxide of chitin). And after, the alkali chitin is allowed to react with monochloroacetic acid to synthesize 6-O-(carboxymethyl) chitin [CM-Chitin] under diminished pressure. In order to synthesize high performance CM-Chitin as hygroscopic agent, it was measured that the yield and degree of subsititution of each CM-Chitin according to molar ratio(monochloroacetic acid equivalent mol/N-acetyl-D-glucosamine residue) and their moisture-absorption and moisture-release properties were measured and compared with those of hyaluronic acid. The moisture-absorption and moisture-release properties of CM-Chitin, especially 0.8 in degree of substitution, were found quite similar to those of hyaluronic acid. The preliminary results show that CM-Chitin might be used as hygroscopic agent instead of hyaluronic acid in field of cosmetics.

This study was carried out to investigate the economic value of organic rice production using gelatin ․ chitin microorganisms in eco-friendly complex, Gongsan, Naju city. The soil condition of experiment paddy field was Jeonbuk series and silt loam with a slightly poor drainage. Except for the high effective silicate, the chemical characteristics of soils used were included in the optimum range of paddy soils in Korea. In growth, plant length, tiller number, ear number, and ear length were observed to be higher in conventional paddy fields than organic paddy fields. However, number of grain per panicle and grain filling ratio (%) were higher in organic paddy fields than conventional paddy fields. Incidences of diseases and insect pests were slightly higher in the organic paddy fields. Water weevil, sheath blight, rice leaf roller and rice blast were more occurred in organic paddy field. On the other hand, false smut was higher occurred in conventional paddy field. There was a significant negative correlation between rice sheath blight and rice leaf roller, and rice yield. In the milled rice quality, the quality of organically cultivated milled rices was lower by the increase of broken rice than that of conventionally cultivated milled rices. The quality and palatability of rice were higher in organic cultivation with decreasing of protein content. Net income of conventionally and organically cultivated rice was 360,000 won/10a and 610,000 won/10a, respectively. Premium net income of the organically cultivated rice was 68%.

The quality changes of strawberries packaged using low density polyethylene (LDPE) film filled with 3% silver-coated ceramic (WC30) and filled with it and 0.1% chitin (CWC) were investigated during storage at 2 for 5 days. In gas composition within film bag, CWC and WC30 kept higher CO2 concentration than LDPE without silver-coated ceramic and chitin (CO) did during 5 day storage. The weight loss of strawberries during storage was the smallest in WC30 and the largest in CWC in 5 days. Hardness of strawberries was the highest in WC30 and the lowest in CO during 5 day storage. pH of strwberries was increased a little until 1 day and was not changed after 1 day storage, and soluble solid content was not changed during storage. Vitamin C content was decreased significantly until 2 day storage and decreased a little after 2 days. There is no differences in the change of vitamin C content among the packaging materials. In color measurement, lightness was the highest in WC 30 and in sensory evaluation, all characteristics also had the highest scores in WC30. In conclusion, better quality of straberries was shown in WC30 than in CWC and CO during storage.