• Applied Microscopy
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• v.15 no.1
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• pp.13-30
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• 1985

This study was undertaken to investigate the effect of lead on organisms. Mice received 15mg or 30mg of lead acetate per kg body weight every day for 1, 2 or 3 weeks, and the livers and kidneys were removed 24h after repeated injections. The livers and kidneys were used as sources for measurement of enzyme activities and for observation of alterations in ultrastructure. It was observed that body weights of mice treated with lead acetate were decreased when compared with those before treatment. This decrease in body weight was proportional to dose. The enzyme activities of succinate and malate dehydrogenases of experimental group that was treated with lead acetate for 1 week were nearly unchanged when compared with controls, but the enzyme activities of experimental group that was treated with lead acetate for 2 or 3 weeks were lower than those of controls. Changes in the enzyme activities were dependent on, but were not proportional to dose. Histologic examination of livers and kidneys after lead treatment showed that lead compound was accumulated and damaged in nucleus and mitochondria mainly. It was also observed that intranuclear inclusion bodies were formed only in epithelial cell of kidney proximal tubule after lead treatment. The overall changes in the ultrastructure were much greater in the livers than in the kidneys. From the above results, it nay be possible to conclude that the lead results in the decrease in body weight, reduction in the succinate dehydrogenate and malate dehydrogenase activities, and damages in the ultrastructure of kidney and liver in mouse. The presence of intranuclear inclusion bodies only in the kidney implies that these bodies protect the kidney from lead toxicity to some extent.

• Journal of fish pathology
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• v.3 no.1
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• pp.1-9
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• 1990

The present study was carried out to reveal the characteristics of organism responsible for so called vibriosis prevailing in warm water season among cultured kuruma prawn Penaeus japonicus. A bacterium was isolated from the heart, lymphoid organ and muscle of the diseased kuruma prawn. Six strains obtained from diseased kuruma prawn in some culture farms in Namhae and Anhung from august to october in 1989 were submitted to the morphological, biochemical and physiological characterization. All the strains were gram-negative, nonsporning short rods with one polar flagellum. Glucose was fermented with no gas production by these strains. Some distinguishing features of the organisms were negative to lysine, arginine, ornithine decarboxilization test. In general, the temperature $20{\sim}27^{\circ}C$, the NaCl concentration of 2~3% and pH of 6~8 were optimal for the growth in peptone water. The organisms were sensitive to the vibrio static agent 0/129. The isolated should be identified as Vibrio sp.. No essential differences in histopathological finding were noted between the naturally and the experimentally infected prawns. Most characteristic pathological changes were extensive necrosis caused by severe bacteria invasion and multiple formation of meranized nodules in the lymphoid organ.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.321-328
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• 2011

Edible films were developed from jujube (Zizyphus jujube Miller) using depolymerization processes of ultrasound and high-pressure homogenization. A 4.6% (w/w) jujube hydrocolloid was treated by ultrasound (600W, 20 min) or homogenized at high pressure (172 MPa, 6 s) and mixed with whey protein isolate, glycerol, xanthan, and sucrose esters of fatty acids to form film-forming solutions from which films were formed by drying. The film prepared by highpressure homogenization (HPH film) produced more homogeneous films without particles than those prepared without depolymerization or with the ultrasound treatment. HPH films possessed the highest tensile strength (4.7MPa), the lowest water vapor permeability ($2.9g{\cdot}mm/kPa{\cdot}h{\cdot}m^2$), and the most uniform and dense microstructures among the films. Flavor profiles of jujube powder and the films were distinguishable. Heat seal strength and oxygen permeability of the HPH films were 44.4 N/m and $0.025mL{\cdot}{\mu}m/m^2$/day/Pa, respectively. Antioxidant activities of jujube power and HPH films were not significantly different.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.3
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• pp.260-266
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• 2013

The study was carried out to determine the gel pasting properties of barley (Hordeum vulgare L. cv. Geoncheonheugbori) as affected by different proton beam irradiation. The ${\lambda}max$, blue value, and amylose content were significantly associated with increasing proton beam irradiation. The pasting time in barley flour irradiated with proton beam ranged 0.09 to 0.16 min shorter than nonirradiated barley flour. Gel pasting temperature ranged 57.4 to $60.5^{\circ}C$. Gel pasting temperature in barley flour decreased with increasing proton beam irradiation. Proton beam irradiation caused a significant decrease in the onset temperature (To), peak temperature (Tp), conclusion temperature (Tc) and enthalpy change (${\Delta}H$). Gelatinization range (R) in barley starch was more broaden than that of non-irradiated barley starch. Barley starches gave the strong diffraction peak at around $2{\Theta}$ values$15^{\circ}$, $18^{\circ}$, $20^{\circ}$, and $23^{\circ}$ $2{\Theta}$. Peak intensity tended to increase with increased proton beam irradiation. The granule crystallinity is closely associated with decreased amylose and increased amylopectin component. The crystallinity degree of barley starch irradiated with proton beam was significantly increased and it ranged from 24.9 to 32.9% compared to the non-irradiated barley starches. It might be deduced that proton beam irradiation causes significant changes of properties of starch viscosity in rice, especially at high irradiation of proton beam.

• Journal of Biosystems Engineering
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• v.16 no.1
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• pp.83-89
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• 1991

One of the most serious problems in Korean sericulture farms is to improve the adiabatic conditions for the simple silkworm rearing houses which has been widely adapted since early 1980'. Thus, this study is aimed to solve the problems by selecting the thermal screen material and by finding the method of its instalation. For the study, 4 kinds of materials which are (1) TE005,(2) NW60, (3) NW300 and (4) AL110 are selected and 4 different types of methods which are surrounding boundary of rearing bed(type A), surrounding inside of wall and ceiling (type B), installing on inside of wal ony (type C) and installing on ceiling Inly (type D) are installed. Decision criteria of the best combination of screen material and installation methods is made by calculating the heating load coefficients and by testing the application at the simple silkworm rearing houses. The obtained results are summarized as follows ; 1. The effect of thermal screen on reducing the thermal energy is remarkable. It saves energy more 50% than unscreened simple silkworm rearing houses. 2. From a stand point of a good screed material on thermal energy reduction, the NW300, AL110 and PE005 are recommanded materials. However, NW60 and PE005 are regarded as desirable materials from the practical point view. 3. Also, the effect on thermal energy reduction is largely affected by the method of thermal screen installation. The surrounding boundary of the silkworm rearing bed(type A) is the most desirable method to reduce the energy, which saves 56.6% of it. 4. In the practical application, NW60 and type A is considered to be the best combination of material and installation method. By this combination, the level of maximum heating load can be reduced at the rate of 43% for spring season and 40% for autumn season. 5. Another heating method, comparted heating, can be recommended to save the energy.

• Journal of Animal Science and Technology
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• v.46 no.6
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• pp.967-974
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• 2004

The current study was undertaken to determine the effect of various conjugated linoleic acid (CLA) isomers on differentiation of pig preadipocyte during culture. Preadipocyte(stroma-vascular cell) was isolated from the backfat of newborn pigs and cultured to differentiate into mature fat cell. Different doses of CLA isomers were treated to the culture media at different times. Cell differentiation was determined by measuring the glycerol3-phosphate dehydrogenase activity of the cultured preadipocytes. Twenty and fifty $\mu$M of trans110_cis 12 isomer of CLA inhibited differentiation of pig preadipocyte whereas cis9-cis II isomer stimulated the differentiation. Both cis9-transII and trans9-trans11 isomers showed no effect. Effect of CLA isomer was more evident at the early stage of culture(day 0-8), than the late stage(day 8-14). These results suggest that each CLA isomer has different effect on pig preadipocyte differentiation.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.16 no.1
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• pp.37-42
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• 1980

The purpose of the present study is to find the color induced maximum gathering rate and to observed'the trend of the - gathering rate by using two species of commercial fishes: rock bream, Oplegnathus fasciatus (Temminet et Schlegel) and 'grass puffer, Fugu niphobles (Jordan et Snyder). An experimental tank($360L{\times}50W{\times}55H cm$) was set up in a dark room. An illumination system was attached to the two end of tank to fix horizontal light intensity by co~bination c' one light bulb(20W) and four filters (red, blue, yellow, white) and the five regulating filters in order to fix light intensity. During the experiment water depth was maintained 50 cm lever in the tank. The tank was marked into six longitudinal sections each being 60 em long to observe the distribution of fish. The fish were acclimatized in dark condition for 40 minutes prior to the main experiment. Upon turning on the light, the number of fish in each section was counted 40 times every 30 seconds, and the gathering rates ,were obtain from the average number of fish in each secion. The color induced maximum gathering rate of rock bream appeared to be red, blue yellow and white color orderly.However, that of grass puffer appeared to be blue, white, yellow and red color orderly. Trend of the gathering rate in illumination time showed the remarkable fluctuation in the rock bream and little difference at the two color light sources. However, trend of the gathering rate in illumination time showed the little fluctuation in grass puffer and much difference at the two color light sources.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.82-86
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• 1997

A Korean traditional sweet rice drink "Sikye" was produced from the raw material of 20% of rice and 4% malt supplemented with 2l of tap water, by incubating the mixture at 6$0^{\circ}C$ for 7 hours. The product was found to contain 11.01% of maltose, 5.31% of isomaltooligosaccharides, 1.75% of maltotriose and 0.28% of glucose. Maltose, maltotriose and isomaltooligosaccharides in Sikye were seperated by ethanol (3 volume) precipitation repeated three times, followed by gel chromatography of Toyopearl HW-40S. 1H-NMR analysis revealed that the products of G2 and G3 size had only $\alpha$-1, 4-glucosidic linkage. but isomaltooligosaccharides showed both signal of $\alpha$-1, 4 and $\alpha$-1, 6-glucosidic linkage with its estimation ratio of 5:1. Isomaltooligosaccharides were hydrolyzed to produce maltooligosaccharide series from maltose to maltohexaose by pullulanase. These results, suggest that isomaltooligosaccharides were constructed by maltohexaose main chain with maltose or maltotriose and maltotetraose side chain.ide chain.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.101-104
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• 1995

We isolated sixty lactic acid bacteria(LAB) from lactic fermented products. Among 60 isolates of LAB, 30 isolates were identified as Lactobacillus casei ssp.(5 strains), Lactobacillus acidophilus(2 strains), Lactobacillus delbrueckii ssp. bulgaricus(6 strains), Lactobacillus plantarum(4 strains), Streptococcus salivarius ssp. thermophilus(11 strains), and Streptococcus faecalis(2 strains). The acid tolerance and bile resistance of 30 LAB were determined. Because the acid tolerance was affected by the initial cell concentrations, the analysis of covariance could be used to remove the effect of initial cells on acid tolerance when testing for differences in acid tolerance among six species. Viability of LAB under acidic condition, pH 3 for 2 hours at $37^{\circ}C$, was significantly different among the species. L. casei and L. acidophilus strains showed great viability, but L. bulgaricus and S. thermophilus strains were very weak in acid tolerance.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.3
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• pp.172-183
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• 2005

To assess the macrobenthic community of oligohaline Youngam Lake, which is located at the Youngsan Watershed on the southwest part of Korea, macrobenthic fauna were collected at 45 stations during May, 2002. A total of 16 species of macrofauna were recorded with a mean density of 240 individuals per $m^2$ and a mean biomass of 7.07 g wet weight per $m^2$. Major dominant faunal groups were crustacean arthropods in terms of the number of species and abundance, and polychaete annelids in terms of biomass. The mean grain size was $5.7\;{\phi}$ which was dominated by silt fraction. The hydrological environment of the lake was characterised as an oligohaline environment with a mean surface water temperature of $17.8^{\circ}C$ and a mean salinity of 2.08 psu. The major dominant species were amphipods, Corophium sp. ($31\%$) and Jesogammarus sp. ($25\%$). Lowe. values of species diversity (H') with a mean of 0.81 (less than 1.0 from most stations) reflected the overall poor faunal diversity in this area. Multivariate analysis suggested that this benthic faunal community could be divided into four sub-regions such as the area from lake proper to water channel to the south, the stations located at the entrance and northern water channel, the stations near the dike, and the lake proper area. Freshwater and brackish water species which occurred in each station group were corresponded to the oligohaline salinity regime. Bottom hypoxia appeared in the entrance part of the lake between dyke and lake proper on May, which was resulted from stratification from spring season. These facts imply that marine macrobenthos were severely impacted by low salinity and a consequent hypoxia after embankment of the lake due to the restriction of water circulation.