• Analytical Science and Technology
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• v.16 no.2
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• pp.117-124
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• 2003

Oxygen to metal ratio has been measured by wet and dry chemical analysis to study the properties of sintered $UO_2$ pellets and $U_3O_8$ in the lithium reduction process of spent pressurized water reactor fuels. Uranium dioxide pellets simulated for the spent PWR fuels with burnup values of 20,000~60,000 MWd/MtU were prepared by mixing $UO_2$ powder and oxides of fission product elements, pelleting the powder mixture and sintering it at $1,700^{\circ}C$ under a hydrogen atmosphere. For wet chemical analysis, the simulated spent fuels were dissolved with mixed acid (10 M HCl : 8 M $HNO_3$, 2.5 : 1, v/v) using acid digestion bomb technique. The total amount of uranium and fission products added in the simulated spent fuels were measured using inductively coupled plasma atomic emission spectrometry. Weight change of the simulated fuel during its oxydation was measured by thermogravimetry and then the O/M ratio result was compared to that obtained by wet chemical analysis. Influence of $Mo_{0.4}-Ru_{0.4}-Rh_{0.1}-Pd_{0.1}$, quaternary alloy, on the determination of O/M ratio was investigated.

• Journal of Korea Foresty Energy
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• v.19 no.2
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• pp.93-101
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• 2000

Wood of Robinia pseudoacacia and bark of Populus alba$\times$P. glandulosa, Fraxinus rhynchophylla and Ulmus davidiana var. japonica were collected and extracted with acetone-water(7:3, v/v) in glass jar to examine whether its bioactive compounds exist. The concentrated extracts were fractionated with hexane, chloroform, ethylacetate and water, and then freeze-dried for column chromatography and bioactive tests. The isolated compounds were sakuranetin-5-O-$\beta$-D-glucopyranoside from Populus alba $\times$Pl glandulosa, 4--ethyoxy-(+)-leucorobinetinidin frm R. pseudoacacia and fraxetion from F. rhynchophylla and were characterized by $^1H$ and$^{13}C $ NMR and positive FAB-MS. Decay-resistant activity was expressed by weight loss ratio and hyphae growth inhibition in the wood dust agar medium inoculated wood rot fungi. R. pseudoacacia showed best anti-decaying property in both test and its methanol untreated samples, indicating higher activity than methanol treated samples in hyphae grwoth test. In antioxidative test, $\alpha$-tocopherol, one of natural antioxidants, and BHT, one of synthetic antioxidants, were used as references to cmpare with the antioxidant activities of the extacted fractions. Ethylacetate fraction of F. rhynchophylla bark indicated the hightest activity in this test and all fractions of R. pseudiacacia extractives also indicated higher activities compared with the other fractions. In the isolated compounds, aesculetin isolated from F. rhynchophylla bark showed best activity and followed by robonetinidin from R. pseudoacaica.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.893-899
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• 2004

Method for sample preparation and quantitative analysis of 19 permitted and non-permitted synthetic colors in foods was developed based on reversed-phase ion-pairing high performance liquid chromatography. For color extraction of samples, deionized water was added, and pH was appropriately adjusted with 1% ammonia water. Any undissolved matters were extracted with 50% ethanol or 70% methanol. Lipid in snacks was first removed using n-hexane with centrifugation, water was added to extract colors, followed by clean-up and concentration using Sep-Pak $C_{18}$ cartridge. Recovery efficiencies at known concentrations of 19 standard food colors spiked into foods were in 90.3-97.9% range far soft drink, 79.2-101.9% for candy, 84.1-103.4% for jelly, 86.4-100.8% for chewing gum, 83.5-103.4% for ice cream, and 78.5-95.6% for snack.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.357-368
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• 1996

To utilize the ascidian tunic as a natural pigment and dietary sources for rainbow trout (Oncorhynchus mykiss), juvenile were fed on experimental diets containing enzymatic hydrolysates of ascidian tunic treated with three commercial mined enzymes (ultrazyme, cellulase, viscozyme) for 12 weeks. From the results of feeding experiment, similar growth rate was checked in the enzymatic hydrolysis group compared with control, and those were a higher than of ascidian tunic powder group. The total acetone extractable pigment in muscle of the enzymatic hydrolysates group was lower than that of the ascidian extracts group and carophyll pink group until 8 weeks, but the level of those pigment of the enzymatic hydrolysates was similar to the ascidian extracts and carophyll pink group after 12 weeks. The lipid content was increased with the pigment concentration in the all experimental group. But the ascidian tunic pigment did not influence on the composition of the fatty acids in the muscle and liver. From the consideration of results for pigmentation, the enzymatic hydrolysates of ascidian tunic were suitable for both a natural pigment and dietary protein and carbohydrates sources as a substitute synthetic pigment for aquaculture use.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.362-371
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• 2012

Objective of this research was to secure the information on physical and chemical properties of peatmoss and coir dust. To achieve this, 6 kinds of peatmoss and 10 kinds of coir dust currently used in the country as the root medium components in plant factories were collected and analysed. The mean ${\pm}$ standard deviation (SD) of total porosity and container capacity in peatmoss and coir dust were $79.6{\pm}5.04$ and $83.6{\pm}6.18%$, and $69.9{\pm}10.17$ and $65.9{\pm}3.46%$, respectively. These indicate that peatmoss has higher water holding capacity than coir dust and the characteristics are highly varied among peatmoss. The 4 out of 5 kinds of peatmoss had lower than 10%, but coir dust had 12~26%, of air-filled porosity. The percentage of easily available water and buffering water in peatmoss and coir dust was 18~22 and 11~16% and 9~13 and 5.5~7.5%, respectively. These results indicate that precise irrigation is required when coir dust is used as the root medium. The ranges of pH and electrical conductivity (EC) were 3.46~4.17 and $0.137{\sim}0.253dS{\cdot}m^{-1}$ in peatmoss and 5.31~6.48 and $0.250{\sim}0.1.580dS{\cdot}m^{-1}$ in coir dust. However, $0.563{\pm}0.83dS{\cdot}m^{-1}$ in mean ${\pm}$SD of coir dust EC indicates that it is higher than that of peatmoss, and the coir dust are highly varied in EC. The cation exchange capacity of peatmoss was 3 to 4 times as high as that of coir dust. The coir dust had higher $NO_3$ and $PO_4$ and lower $NH_4$ than peatmoss. The K and Na concentrations in coir dust were extremely high indicating that these ions caused the rising in EC. The percentage of hot water and alkali extracts of peatmoss were 6.67~16.37 and 0~38%, whereas those of coir dust were 30.0~65.1 and 23.1~70.3%. These results mean that possible existence of growth inhibiting materials in coir dust.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.1
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• pp.70-73
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• 2004

The browning rate of potato juice alone and potato juice with added carrot juice or water(1:1 by volume) were studied. As the amount of carrot juice added was increased, the browning rate proportionally decreased: from 1.86 of potato juice alone to 0.36 for the potato juice and carrot juice mixture(l:1). This inhibitory effect of carrot juice on browning led us to assume that $\beta$-carotene, the major constituent of carrot carotenoids, may be involved in impeding the browning reaction of potato juice. Therefore, model system of enzymatic browning, consisting of chi orogenic acid/tyrosine and $\beta$-carotene/carrot carotenoids, were studied. The results shows the browning rates of chlorogenic acid alone and chlorogenic acid with added $\beta$-carotene. The initial browning rate of chlorogenic acid was faster($\delta$L= 1.1/min.)than that of chlorogenic acid with added $\beta$-carotene($\delta$L=0.6/min.).

• Journal of Mushroom
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• v.13 no.1
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• pp.16-20
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• 2015

Water extracts from spent mushroom substrate (SMSE)of edible mushrooms, Pleurotus eryngii, Hericium erinaceus and Lentinula edodes promoted growth of pepper seedling. Mycellial growth rate of Phythopthora capsici and Fusarium oxysporum was dramatically inhibited by 100% and 70% on PDA added with SMSE of H. erinaceus. SMSEs from H. erinaceus, P. eryngii, and L. edodes effectively reduced the disease severity of Phytophthora blight of pepper caused by Phytophthora capsici to 75%, 10% and 35%, respectively. These results suggested that SMSE from the mushrooms have dual effects that suppress phythopthora blight disease and promote plant growth of pepper.

• Applied Biological Chemistry
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• v.24 no.4
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• pp.238-244
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• 1981

The thin Layer chromatographic determination of ${\alpha}-solanine $ in potato tuber was investigated. The solanine was extracted with methanol-chloroform mixture (2 : 1, v/v) and precipitated as the crude glycoalkaloid by the addition of ammonium hydroxide. The solanine in the crude precipitate was separated by TLC using a solvent system of 1% $NH_4OH-absolute$ ethanol-chloroform (1:2:2, v/v). The purity of ${\alpha}-solanine $ was confirmed by infrared spectrophotometry. The ${\alpha}-solanine $ separated by TLC was determined at the wavelength of 310nm after coloration with concentrated sulfuric acid-1% paraformaldehyde, with the molar absorptivity of 2,090.

• Applied Biological Chemistry
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• v.4
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• pp.23-28
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• 1963

Various species of the genus Capsicum contain in their fruits an intensively sharp and pungent substance, Capsaicin, which was first isolated in an almost pure state by Thresh. Containing the pungent principle, Capsicums are used extensively in food as a spice and in medicine as a rubefacient and carminative. Numerous methods have been proposed for the isolation, the chemical structure and the quantitative determination of Capsaicin. Modifying the several methods described before, the Capsaicin contents in various species of the genus Capsicum were determined as follows. (1) The isolation of pure Capsaicin was the essential first step for the determination of Capsaicin contents. Powdered cayenne pepper was extracted with acetone. By the method of ether alkali partition extraction slightly modified at this laboratory and by the recrystallization with light petroleum ether that was repeated ten times, the pure crystalline Capsaicin was obtained. Using this Capsaicin, the standard absorption curve was drawn with Beckman spectrophotometer model DU for the quantitative determination of Capsaicin. 92) The powdered sample was extracted in a Soxhlet extractor with ether-acetone solvent system(3:1) for 25 hours. Capsaicin in this ether-acetone extracts was efficiently separated in a pure state by paper partition chromatography using 58% methanol solution as developing agent. It was found that 58% methanol was one of the most valuable solvent to separate Capsaicin from impurities such as sterols, fatty acids, waxes and carotenoid pigments. (3) The colorimetric method modifying the Schulte-Kruger's method which consists of measuring the red color produced with diazobenzenesulphonic acid was used. Capsaicin in various species of the genus Capsicum was determined quantitatively with use of Beckman spectrophotometer model DU at $480\;m{\mu}$.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.271-276
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• 1999

Several Streptomyces strains were tested for potent antifungal agents active against phytopathogenic fungi. Among the tested, S. hygroscopicus MJM1004 showed a potent antifungal activity when assayed using Candida albicans as indicator organism. With the strain of MJM1004, fermentation medium for the production of an antifungal agent was developed with varying carbon sources, nitrogen sources, and mineral elements, which resulted in the highest productivity in the medium containing 2% soybean meal, 1% glucose, 2% starch, 0.3% $CaCO_3$, 0.05% $MgSO_4{\cdot}7H_2O$, 0.05% $K_2HPO_4$. The active compound showed a broad spectrum of antifungal activity against several plant pathogenic fungi. The antifungal compound was purified and showed the physicochemical characteristics similar to azalomycin F complex in NMR and MS analysis.