• 한국수산과학회지
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• 제9권2호
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• pp.111-119
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• 1976

Discoloration of canned boiled oyster namely greening, yellowing and browning often occur separately or associatively in the storage of the product. Greening is mainly caused by the appearance of chlorophyll and its derivatives on the surface around the digestive diverticula of the oyster and yellowing by dispersion of carotenoid. Browning reactions by sugar amino condensation or enzymatic action, tyrosinase, also cause an undesirable color development. In this paper, the stability and the changes in distributional or partitional ratio of chlorophyll and carotenoid pigment of meat vs viscera in raw and canned oyster during six month storage in order to measure the dispersion rate of both pigments between meat and viscera, and to evaluate the feasibility of discoloration of oyster meat. The development of brownish pigment and the toss of free tyrosine in oyster were also determined to compare the readiness of color development. In addition the influence of processing and storage conditions to the dispersion rate and the tendency of discoloration, and finally the effect of inhibitor were discussed. The results showed that greening or yellowing was initiated by the dispersion of chlorophyll or carotenoids from viscera to the meat of oyster, and the dispersion rate of carotenoid was much higher than the chlorophyll's, so that, yellowing appeared a leading reaction of discoloration. The dispersion rate was obviously fastened by raising the temperature in the process of sterilization and storage. Consequently, the low temperature storage could largely retard the occurance of yellowing or greening of oyster meat. The pH control of canned oyster did not seem to affect the dispersion of pigment but significantly did on the stability of the piqments. Browning by the reaction of sugar-amino condensation and enzymatic oxidation of tyrosine was positively detected in canned oyster meat. The development of brownish color was influenced rather by the storage temperature than the heating process. Addition of sodium sulfite in can or treating the boiled oyster with sulfite solution prior to filling seemed possibly inhibit the color development particularly in cold-storaged oyster meat.

• 한국식품영양과학회지
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• 제22권5호
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• pp.565-569
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• 1993

동결건조한 양조간장의 분말로 부터 갈색물질을 Sephadex G-10으로 겔-여과 크로마토그라피법에 의하여 분획한 다음 이를 동결건조하여 분말로 만든 후, 동갈색물질의 항산화력을 다른 항산화제인 부틸히드록시아니졸(BHA) 및 ${\alpha}-토코패롤과$ 비교하여 보았다. 갈색물질 및 양조간장은 다 같이 지방산의 산화반응에 있어서 과산화물의 생성을 크게 저해시켰고, 갈색물질이 양조간장 자체보다 항산화 효과가 더 높았으며 농도에 비례하여 항산화성이 증대되었다. 그러나 갈색물질의 항산화력은 과산화물 생성억제 능력 그리고 conjugated dienoic acid 생성저해 능력 등에서 BHA 및 ${\alpha}-토코페롤$ 보다는 낮았다. 이와같은 양조간장의 갈색물질의 항산화성은 그 획분이 대량 섭취도고 있는 발효조미식품이라는 점에서 중요한 의의를 가질 것으로 판단된다.

• Korean Membrane Journal
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• 제7권1호
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• pp.28-33
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• 2005

The feasibility of producing sulfuric acid and ammonia water from ammonium sulfate was investigated by an integrated process including ammonia stripping (AS) and electrodialysis with bipolar membrane (EDBM). It was suggested that the production of sulfuric acid using ammonia stripping-electrodialysis with bipolar membrane (ASEDBM) was effective in obtaining high concentration of sulfuric acid compared with EDBM alone. AS was carried out over pH 11 and within the range of temperatures, $20^{\circ}C{\~}60^{\circ}C$. Sodium sulfate obtained using AS was used as the feed solution of EDBM. The recovery of ammonia increased from $40\%$ to $80\%$ at $60^{\circ}C$ due to the increased mobility of ammonium ion. A pilot-scale EDBM system, which is composed of two compartments and 10 cell pairs with an effective membrane area of $200 cm^2$ per cell, was used for the recovery of sulfuric acid. The performance was examined in the range of 0.1 M${\~}$1.0 M concentration of concentrate compartment and of $25 mA/cm^2{\~}62.5 mA/cm^2$ of current density. The maximum current efficiency of $64.9\%$ was obtained at 0.1 M sulfuric acid because the diffusion rate at the anion exchange membrane decreased as the sulfuric acid of the concentrate compartment decreased. It was possible to obtain the 2.5 M of sulfuric acid in the $62.5 mA/cm^2$ with a power consumption of 13.0 kWh/ton, while the concentration of sulfuric acid was proportional to the current density below the limiting current density (LCD). Thus, the integrating process of AS-EDBM enables to recover sulfuric acid from the wastewaters containing ammonium sulfate.

• Preventive Nutrition and Food Science
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• 제2권1호
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• pp.49-54
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• 1997

The modifying effects of Chelidonium majus L/(Papaeracea)herb extract(CH) ,and analgesic traditionally prescribed for gastric and duodenal ulcer patients, on gastric tumor development given Ν-methyl-Ν'-nitro-Ν-nitrosogyanidine(MNNG) were studied in sixty-four 6 week-old male Wistar rats. Group 1 rats were ini-tially given MNNG(200mg/kg b/w.) by gavage ar days 0 and 14 as well as saturated sodium chloride solution(S-NaCI, 1ml per rat) every 3 days during weeks 0 to 3(6 times) and then placed on basal diet containing 0.1 or 0.2% CH ofr 16 weeks from week 4. Rats of Groups 2 and 3 were treated with MNNG together with S-NaCI or saline(0.9% NaCI, 21ml per rat) respectively, timed as in Group 1 but without further treatment. All survival animals were killed at week 20 and histopathologically investigate. in the glandular stomach, the number of preneoplastic pepsinogen 1 altered pyloric glands(PAPGs) in the MNNG+S-NaCI→CH(0.1%) group(Group 1) was significantly smaller than in the MNNG+S-NaCI group(Group 2)(p<0.02). The inci-dences of forestomach neoplastic lesions (Papillomas and squamous cell carcinomas)also showed a tendency for decrease with the CH treatment. The results thus indicate that C"H exerts inhibitory effects on glandular for decrease with the CH treatment. The results thus indicate that CH exerts inhibitory effects on glandular stomach carcinogenesis in the rat, so that it may have potential as a chemopreventive agent for stomach cancer in man.

• 한국지역사회생활과학회지
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• 제21권4호
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• pp.641-649
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• 2010

To make sure of the usefulness of extract of Rubus coreanus Miquel for producing functional feeding honey, we compared some antioxidative indicators of feeding honey using extract of Rubus coreanus Miquel with acacia honey, SueBee Clover honey(USA), feeding honey on the market. The water content of four honeys were 16.6~26.5%, pH were 3.18~3.70, and titratable acidity ranged 0.018~0.022%. The phenolic compound contents of SueBee Clover honey and feeding honey using extract of Rubus coreanus Miquel were 8.3 mg/100 g and 7.3 mg/100 g, respectively, and were significaltly higher thgheacacia honey and feeding honey on the market. The flavonoid contents per 100 g of honey ranged from 2.3 mg(acacia honey) to 15.0 mg(SueBee Clover honey). DPPH anion scavenging activity of four honeys were not high. 0.5~2.0 g/ml of feeding honey using extract of Rubus coreanus Miquel was 16~36% and showed a concentration-reliant figure. At the concentration of 0.25~0.75 mg/ml, the reducing power of four honeys increased concentration-dependently, and the power of 0.25 mg/ml of feeding honey using extract of Rubus coreanus Miquel was corresponding to thgt of $150{\mu}g$/ml of a vitamin C solution. ABTS radical scavenging activity of feeding honey using extract of Rubus coreanus Miquel was 43.3~68.4%; the highest activity amongst all samples. When plotting the dose-response curve, ABTS radical scavenging activity also increased as their concentration increased from 62.5 mg/ml to 500 mg/ml. The heat treatment reduced the phenolic compound contents of acacia honey and feeding honey using extract of Rubus coreanus DPPH anion scavenging activity of feeding honey on the market and feeding honey using extract of Rubus coreanus Miquel did not changed significaltly after heating for 20 min, and the three honey except SueBee Clover honey maintained the reducing power with the same treatment.

• Journal of Photoscience
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• 제4권3호
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• pp.147-160
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• 1997

INTRODUCTION : Various types of organic reactions in the crystalline state, so-called "topochemical reaction", have been reported in this century." Among the reactions, [2+2] photocycloaddition of diolefin crystals are one of the most intensively investigated examples. In the topochemical reaction in a pure sense, the space group symmetry is perfectly preserved throughout the reaction as were demonstrated by the crystalline-state photopolymerization of 2,5-distyrylpyrazine (2,5-DSP) and photodimerization of propyl $\alpha$-cyano-4-[2-(4-pyridyl) ethenyl]cinnamate. 2,5-DSP was initially prepared by Franke and in 1958 Koelsch and Gumprecht described briefly in their article of diazine-derivatives that it was found that the compound (2,5-DsP) was converted into a colorless insoluble polymer (\ulcorner) dec. 331~331$\circ$ when the solid was exposed for a few hours to ultraviolet light. Wright described in his book as if Koelsch and Gumprecht had investigated both the structure of the photoproduct and the crystal structure 2,5-DSP in detail. However, in the paper, they have not described any study on chemically correct analysis and crystallography of the resulting photoproduct at all. In 1967, one of present authors (M. H.) independently made the same observation as Franke that brilliant yellow crystal of 2,5-DSP was converted into powdery white substance under the sunlight in the course of a preparative study of pyrazine-2,5-dicarboxylic acid from 2,5-DSP. He investigated this phenomenon and concluded for the first time that a linear highmolecular-weight polymer crystal ([$\eta$] > 3.0 in $CF_3COOH$ solution) with recurring cyclobutane units in the main chain, had been produced from 2,5-DSP crystal by the action of sunlight.on of sunlight.

• Journal of Chest Surgery
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• 제22권2호
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• pp.179-190
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• 1989

The experimental study for extracorporeal preservation of the heart-lung preparation by autoperfusion system was performed in 10 dogs. Under intravenous Pentothal endotracheal anesthesia bilateral thoracotomies were performed. A 24F cannula connected to a plastic reservoir bag located 100 cm above the level of the heart was introduced into the aortic arch. Left subclavian, innominate artery, and descending aorta were ligated and divided. Both vena cavae were ligated and divided after the bag was half filled with blood. A 24F catheter inserted into right atrium and connected to the plastic bag in order to keep constant the preload. The thoracic trachea was intubated and the lungs were ventilated. The heart-lung preparations were removed en bloc and floated in a $34^{\circ}C$ bath of Hartmann solution. The preparations were observed for from 2 hours to 8 hours, with the average of 5.2 hours. Hemodynamic and hematologic variables were measured during preharvest and autoperfusion. The pH revealed severe respiratory alkalosis due to very low $PaCO_2$ during autoperfusion ; $PaO_2$ remained constant for 130-140 mmHg; $A-aDO_2$ increased markedly. The static inspiratory pressure [SIP] at late autoperfusion [6hr] increased significantly as compared with at early autoperfusion [2hr]. There was no difference between white blood cell counts from right atrium and those of left atrium. Heart rates remained constant for 110-120/min; cardiac outputs maintained to approximately 0.6L/min; mean aortic pressures, 75 mmHg; mean pulmonary arterial pressures, 15-18 mmHg; mean right atrial pressures, 9-13 mmHg; mean left atrial pressures, 12 mmHg lower than those of right atrium. Serum Na maintained with normal range during autoperfusion; K increased significantly; Ca decreased progressively. Hemoglobin and hematocrit decreased significantly during autoperfusion. The study demonstrated that stable hemodynamics could be maintained throughout the experiment and the preparation of the lung seemed to be inadequate, especially after 3-4 hours, such as high $A-aDO_2$, increased SIP, and scattered atelectasis and edema in their gross appearances.

• 한국물환경학회지
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• 제20권6호
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• pp.670-675
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• 2004

Humic acids are macromolecules originated from natural water, soil, and sediment. The characteristics of humic acid enable it to change the distribution of metals as well as many kinds of organic contaminants and to determine the sorption of them from soil solution. To see the effect of humic acid on the removal rate of organic contaminants and heavy metals, batch-scale experiments were performed. As a natural geosorbent, black shale was used as a sorbent media, which showed hight sorption capacity of trichloroethylene (TCE), lead, cadmium and chromium. The effect of sorption-desorption, pH, ionic strength and the concentration of humic acid was taken into consideration. TCE sorption capacity by black shale was compared to natural bentonite and hexadecyltrimethylammonium (HDTMA) modified bentonite. The removal rate was good and humic acid also sorbed onto black shale very well. The organic part of humic acid could effectively enhance the partition of TCE and it act as an electron donor to reduce Cr(VI) to Cr(III). Cationic metal of Pb(II) and Cd(II) also removed from the water by black shale. With 3 mg/L of humic acid, both Pb(II) and Cd(II) were removed more than without humic acid. That could be explained by sorption and complexation with humic acid and that was possible when humic acid could change the hydrophobicity and solubility of heavy metals. Humic acid exhibited desorption-resistivity with black shale, which implied that black shale could be an alternative sorbent or material for remediation of organic contaminants and heavy metals.

• 한국식품영양학회지
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• 제20권2호
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• pp.195-201
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• 2007

This study were investigated the changes in chemical components, quality characteristics of the fermented broth, and physiological functionality during fermentation period of fruit, vegetables, and medicinal herbs. pH and $^{\circ}$Bx gradually decreased and the viscosity increased. The chromaticity of L, a, and b all increased. The total number of germs dropped from $10^5{\sim}10^6\;to\;10^2{\sim}10^3$ CFU/ml, and that of lactobacilli also decreased noticeably. According to the result of the effect on fat oxidation, a very low level of TBARS was shown. After thirty days of fermentation, the amount of each fermentation broth increased more or less, but as it declined considerably after ninety days, it was found that the binding effect of $Fe^{2+}$ ion was small and insignificant. The electron donating ability, though not reaching 0.5% ascorbic acid, showed a high level of activity from $33.71{\sim}72.15%$ before fifteen days and $44.76{\sim}75.20%$ ninety days after fermentation. Among them, the fruit fermentation solution showed the highest activity. It was also found that the organic functions for each fermentation broth decreased more or less depending on the fermentation period and the thirty-days-old fermentation broth were favored most. On the basis of the above experiment results, it can be concluded that the optimum fermentation period for fruit, vegetables, and medicinal herb is thirty to ninety days.

• 한국식물병리학회지
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• 제14권6호
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• pp.646-650
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• 1998

Mycological characteristics of Phytophthora nicotianae var. nicotianae SPC10 (A1 type) causing Phytophthora rot of strawberry and the resistances of 11 strawberry cultivars against the pathogen were examined. Optimum temperature for the mycelial growth of the pathogen was obtained in the range of 30~35$^{\circ}C$, and the growth was completely stopped under 13$^{\circ}C$ or over 42$^{\circ}C$. Aerial mycelia were abundant on oatmeal agar (OMA), V-8 juice agar (V8A) and lima bean agar (LBA) medium, although there were slight differences, however, on cornmeal agar (CMA) medium, it was a shape of stellate without aerial mycelia. The colony shape on potato dextrose agar (PDA) medium was rough and irregular whereas the mycelial growth was slow, and some aerial mycelia were only produced in the middle of PDA medium. Optimum temperature for sporangial formation was 3$0^{\circ}C$, and zoospores were mostly released at $25^{\circ}C$ from the sporangia. Sporangia were more produced in C/Z solution with pH 5. 0~6.$0^{\circ}C$ than sterilized distilled water (DSW) and distilled water (DW), and zoospores were also released much more than other solutions. Eleven strawberry cultivars such as Reiko, Hokowase, Eyeberry, Akaneko, Sistakara, Toyonoka, Nyoho, Sulhong, Suhong, Myhong and Wonkyo #3104 revealed the disease incidence up to 88.9~100% by the leaf inoculation with mycelial disk. However, Nyoho and Suhong showed higher level of resistance against the pathogen by root inoculation.