• The Korean Journal of Zoology
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• v.19 no.3
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• pp.101-112
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• 1976

1. It has been found in the karyotype of Apodemus agrarius coreae that No. 1 chromosome pair is subtelocentric and this is the new chromosome type in comparison with acro-telocentric No. 1 pair of the other subpecies. 2. It was reported in the Karyotype of Microtus fortis from USSR that the autosome consisted of 2 submetacentric, 10 metacentric and 38 acrocentric chromosomes, and that X is acrocentric and Y is small acrocentric one. In the present study, however, the autosome of M. fortis pelliceus in Korea is composed of three groups; 4 subtelocentric, 10 meta-submetacenric, and 36 acrocentric one. And X is the largest metacentric chromosome of the complement. Y is smaller acrocentric one. Thus, it has been found that the karyotype of M. fortis in Korea differs from that of the same species in USSR. In the karyotype of this red vole, two pairs of heteromorohic chromosome with respect to the size of their secondary constrictions have been shown in the acrocentric group. 3. The diploid number of Cricetulus triton nestor was found to be 28, and its chromosome size ranges from 7.5 $\\mu$ to 1.5 $\\mu$. Autosomes contains 11 large acrocentric pairs and two pairs of very small metacentric ones. This feature is simillar to that of Tscherskia triton found USSR.

• The Korean Journal of Zoology
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• v.39 no.1
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• pp.36-46
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• 1996

An endogenous phenoloxidase (EPO) from earthworm, Lumbricus rubellus, has been purified and characterized. The purified EPO using ammonium sulfate fractionation, Blue-2, Phenyl-, and Q-sepharose chromatography steps was revealed in SDS-PAGE as a single protein banri with Mr. of 59 kl)a. A native strudure of the enzyme was examined with an in situ staining of a nondenatudng-PAGE using DL-dopa as a substrate. The result showed that a single band due to the EPO activity was located siighdy above a standard polypeptide with Mr. of 210 kl)a. These fads indicate that the EPO is an oligomeric enzyme. The presence of a monophenolase activity of the purified EPO, which hydroxylates tyrosine to dopa, was confirmed by observing dopachrome accumulation at 475 nm at PH 8.0 with a typical lag phase during 60 mm. of meausrement. A series of inhibition study has been performed for the enzyme with several divalent cation chelators such as phenyithiourea (Flu), 1, lO-phenanthroline, EDTA, and EGTA. Among them, only V'flj inhibited the enzyme with 1C0.5 of 65 MM, which indicated that copper was critical for the catalysis of EPO. The enzyme was maximally active at 35'C and pH 8.0 when L-dopa to dopachrome conversion was spectrophotometricaily monitored at 475 nm. The apparent Km values of P0 for L-opa were obtained as 1.86 mM and 13.8 mM at pH 6.5 and 8.0, respectively. The catalytic efficiencies at both pH were almost identical [(kat/Km)pH8.0/(kcat/Km)pH6.5 = O.92] while the Vmax at p11 8.0 was 6.6-fold higher than that at pH 6.5. This fact may indicate that pH affeds the catalysis at substrate and/or enzyme-substrate complex level rather than the enzyme itself. Taken together, the EPO was an oligomeric enzyme which did not require proteolysis for its activation. These results also indicated that the enzyme can exist, at least, in part as a latent form In vivo, which might be distinct from the prophenoloxidase activating system. Therefore, it is pertinent to consider that there must be certain regulatory molecules or phenomena in L. rubellus which make the 1,0 in a latent form in vivo before the foreign invasions.

• The Journal of the Petrological Society of Korea
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• v.24 no.2
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• pp.107-124
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• 2015

The 'Imjin System' (or Rimjin System) was established in 1962 as a new stratigraphic unit separated from the Upper Paleozoic Pyeongan System based on the discovery of brachiopods and echinoderms of possible Devonian age. Subsequent discoveries of the Middle Devonian charophytes confirmed the Devonian age of the system. The Imjin System is distributed in the Imjingang Belt between the Pyongnam Basin and the Gyeonggi Massif, spans from the eastern areas including Cholwon-gun of the Gangwon Province, Gumchon-gun, Phanmun-gun, and Tosan-gun of the Hwanghaebuk Province, to the western areas of Gangryong-gun and Ongjin-gun of the Hwanghaenam Province, and includes the Yeoncheon Group (metamorphic complex) to the south. Unlike the lower Paleozoic strata in the Pyongnam Basin which solely produce marine invertebrate fossils, the Imjin System yields diverse non-marine plant and algal fossils. Brachiopods of the system are similar to those from the Devonian of the South China Block and include taxa endemic to the platform, implying a close paleogeographic affinity to the South China Block. The Imjin System is generally considered as of Middle to Late Devonian in age, although there have been suggestions that the system is of the Middle Devonian to Carboniferous in age. North Korean workers postulated that the Imjin System was deposited in the current geographic position, where the "Imjin Sea" (an extension of the South China Platform) was located during the Devonian. The Imjin System displays strong local variations in stratigraphy and its thickness. It has recently been reported that the strata are repeated and overturned by thrust faults in many exposures. The Yeoncheon Group a southward extension of the Imjin System, also experienced intense tight folding and contractional deformation. Northward decrease in metamorphic grade within the system suggests that the northern part of the Gyeonggi Massif and the Imjingang Belt are probably an extension of the Dabie-Sulu Belt between the South China and Sino-Korean blocks, and the Imjin System is an remnant of accretion resulted from the collision between the two blocks. In order to understand tectonic evolution and Paleozoic paleogeography of eastern Asia, further studies on stratigraphic, sedimentologic and tectonic evolution of the Imjin System involving scientists from the two Koreas are urgently needed.

• Food Science and Preservation
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• v.14 no.6
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• pp.662-668
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• 2007

Studies have shown that onions exhibit a wide variety of health-promoting properties. The health benefits by the onion have been attributed to its ability to scavenge free radicals, to reduce blood lipids, to lower blood pressure, and to inhibit platelet aggregation. This study was performed to investigate whether onion extract supplementation would affect the blood markers of ethanol-induced fatty liver in rats. Initially, male Sprague-Dawley rats were housed singly in a room of controlled temperature and lighting and had free access to a nutritionally adequate AIN-93G and deionized water. The rats were trained for meal feeding to prevent a decline in food intake, as inevitably observed following an ethanol feeding. After the training period, rats were weight-matched and assigned to the following three groups: 1) a control group, fed the AIN-93G diet alone (control); 2) an ethanol group, fed the AIN-93G diet with ethanol at 4 g/day/kg body weight (ethanol); and 3) an onion group, fed the AIN-93G diet with ethanol plus supplemental freeze-dried onion powder at 500 mg/day/rat (ethanol + onion). All three group were meal-fed 7.0 g of their respective diets at 0900 h and 7.5 g at 1600 h for 28 days. At 0, 2, and 4 wk, blood was collected via the orbital sinus and organs were collected following overnight food deprivation. Both control and experimental groups continually gained weight throughout the study. No significant differences in the weights of the liver, kidneys, heart, spleen, and testis were observed. However, the serum level of triglycerides was significantly increased by ethanol but significantly decreased by onion extract. The activities of serum glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) at 4 wk were significantly increased by ethanol feeding but were significantly decreased by onion supplementation. However, no differences among groups were observed in the serum levels of alkaline phosphatase, gamma-glutamyl transpeptidase, bilirubin, and protein. These results provide that onion extract favorably affect alcoholic fatty liver by decreasing the serum concentration of triglyceride and the activities of GOT and GPT.

• Food Science and Preservation
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• v.18 no.4
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• pp.459-466
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• 2011

To investigate optimum temperature for storage of fresh ginseng (Panax ginseng C. A. Meyer), the quality of the ginseng was compared during its storage at $-3^{\circ}C$, $-1.5^{\circ}C$ and $0^{\circ}C$. The deterioration rate of fresh ginseng stored at $-3^{\circ}C$ was the lowest for 8 weeks after storage. The rate was rapidly increased after that time and the rate at $-3^{\circ}C$ was higher than that of fresh ginseng stored at $-1.5^{\circ}C$ or $0^{\circ}C$ after the 12th week of storage. The deterioration severity of the fresh ginseng stored at $0^{\circ}C$ was much higher than that of the ginseng stored at $-1.5^{\circ}C$ and $-3^{\circ}C$. The weight loss of fresh ginseng ranged from 0.7---- to 1.6---- after 16th week; it was the lowest in the ginseng stored at $-1.5^{\circ}C$ and similar in fresh ginseng stored at $0^{\circ}C$ and $-3^{\circ}C$. The number of viable cells and molds in the fresh ginseng stored at $-3^{\circ}C$ was smaller than the fresh ginseng that was stored at other temperatures for 12 weeks, but did not differ with different storage temperatures after the 14th week of storage. The surface color of the fresh ginseng at $0^{\circ}C$ or $-1.5^{\circ}C$ was changed little while the discoloration of fresh ginseng at $-3^{\circ}C$ was relatively great. The electrolytic leakage from the rhizome of the fresh ginseng stored at $-3^{\circ}C$ was higher than that of the rhizome stored at $-1.5^{\circ}C$ and $0^{\circ}C$. The overall sensory quality of the fresh ginseng dropped below 3.0 in the S-point scale after the 10th week of storage at $-3^{\circ}C$ and after the 14th week of storage at $-1.5^{\circ}C$ and $0^{\circ}C$ (p<0.05).

• Food Science and Preservation
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• v.18 no.4
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• pp.442-458
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• 2011

Among Cucubitaceae, melon (Cucumis melo) is one of the most diversified fruits, with various forms, sizes, pulps, and peel colors, In addition, it is a commercially important crop because of its high sweetness, deep flavor, and abundant juice. In the species, there are both climacteric and non-climacteric melons depending on the respiration and ethylene production patterns after harvest. Ethylene is also considered a crucial hormone for determining sex expression, Phytohormones other than ethylene interact and regulate ripening, There are some indices that can be used to evaluate the optimum harvest maturity. The harvest time can be estimated after the pollination time, which is the most commonly used method of determining the harvest maturity of the fruit. Besides the physiological aspects, the biochemical alterations, including those of sweetness, firmness, flavor, color, and rind, contribute to the overall fruit quality. These changes can be categorized based on the ethylene-dependent and ethylene-independent phenomena due to the ethylene-suppressed transgenic melon. After harvest, the fruits are precooled to $10^{\circ}C$ to reduce the field heat, after which they are sized and packed. The fruits can be treated with hot water ($60^{\circ}C$ for 60 min) to prevent the softening of the enzyme activity and microorganisms, and with calcium to maintain their firmness. 1-methylenecyclopropene (1-MCP) treatment also maintains their storability by inhibiting respiration and ethylene production. The shelf life of melon is very short even under cold storage, like other cucurbits, and it is prone to obtaining chilling injury under $10^{\circ}C$. In South Korea, low-temperature ($10^{\circ}C$) storage is known to be the best storage condition for the fruit. For long-time transport, CA storage is a good method of maintaining the quality of the fruit by reducing the respiration and ethylene. For fresh-cut processing, washing with a sanitizing agent and packing with plastic-film processing are needed, and low-temperature storage is necessary. The consumer need and demand for fresh-cut melon are growing, but preserving the quality of fresh-cut melon is more challenging than preserving the quality of the whole fruit.

• Food Science and Preservation
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• v.20 no.4
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• pp.583-591
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• 2013

Atopic dermatitis (AD) is a common chronic inflammatory disease associated with a cutaneous hypersensitivity reaction to an allergen. Although the incidence of AD is increasing these days, therapeutics has yet to be developed for its treatment. The aim of this study was conducted in order to compare and investigate the characteristic between the Castanea crenata inner shell extract (CS) and the Castanea crenata inner shell extract fermented by Lactobacillus bifermentans (FCS) for an anti-atopic medication. The total polyphenol and flavonoid contents were similar to CS and FCS. In the DPPH and superoxide anion radical scavenging, the CS and FCS had the potential for antioxidant activities. Both of them did not exhibit cytotoxicity to HS68 cells. The evaluation of the anti-inflammatory activity in Raw264.7 cells demonstrated that the FCS has inhibited the LPS-induced production of nitric oxide as compared to the CS. The anti-atopic dermatitis test was done through the induction of DNCB in AD hairless mice. The FCS has inhibited the development of the atopic dermatitis-like skin lesion by transdermal water loss, melanin and erythema of the skin as compared to the CS. Moreover, the pro-inflammatory cytokine IL-$1{\beta}$ and TNF-${\alpha}$ production in hairless mice were inhibited by the FCS treatment. It indicates that the fermentation of the Castanea crenata inner shell has the potential for the treatment of atopic dermatitis.

• Food Science and Preservation
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• v.20 no.1
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• pp.14-22
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• 2013

The effects of the initial storage temperature and the PA film packaging on the extension of the shelf-life and the improvement of the postharvest storage quality of muskmelons were studied during their storage. Their storage quality was tested as follows: PA-film-wrapped muskmelons, stored at $2^{\circ}C$ or $7^{\circ}C$ for 30 days after their harvest, were kept at $10^{\circ}C$ for 27 days (total: 57 days). On the fifth day of storage at $10^{\circ}C$ (35th day overall), the weight loss reached 6.4% in the 7-control. However, the 2-PA showed the smallest loss of 2.2%. The soluble solids content and the acidity that were measured before the storage were $10.8^{\circ}Brix$ and 0.26% in all the groups. After 27 days of storage at $10^{\circ}C$ (on the 57th day overall), the values were highest in the 2-PA group with $9.7^{\circ}Brix$ and 0.15%, respectively. Microorganisms were not detected at first; but on the fifth day of storage at $10^{\circ}C$ (35th day overall), their values were 3.87 and 2.68 log CFU/g in the seven-control and the 2-PA, respectively. In other words, the 2-PA was found to be more effective in inhibiting microbial proliferation. In relation to sensory properties such as appearance, flavor, sweetness and chewiness, the 2-PA was superior to the other groups and was found to be most effective in improving the storability of muskmelons. In conclusion, it was found that low-temperature injury and fast storage quality deterioration did not occur in film-wrapped muskmelons that were stored at $2^{\circ}C$ for 30 days after they were harvested.

• Food Science and Preservation
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• v.20 no.4
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• pp.564-572
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• 2013

We investigated the quality characteristics of brewing brown rice vinegar through a traditional static fermentation process. Accordingly, we decided to compare the physicochemical characteristics of brewing vinegar at different temperatures and filtration methods. In four to five weeks' time, the acetic acid fermentation exhibited the highest titratable acidity and then it eventually decreased. The titratable acidity was affected by the filtration method. It was revealed that the titratable acidity was higher in the forced filtration than the traditional filtration method. Various organic acids were detected in order to initialize the fermentation stage and as the fermentation progressed, only the acetic acid could be detected. The total free amino acid content was higher at a temperature of $30^{\circ}C$ than at $20^{\circ}C$. Moreover, the free amino acid content was dependent on the acetate content during the acetic fermentation process. The main bioactive substance of the ${\gamma}$-aminobutyric acid content was more than twice at a fermentation temperature of $30^{\circ}C$ compared to the fermentation temperature of $20^{\circ}C$. Furthermore, the total amino acid and essential amino acid content at a temperature of $30^{\circ}C$ was excellent. The quality of the brown rice vinegar via forced filtration method at a temperature of $30^{\circ}C$ was the most excellent. Based on these results, the fermentation temperature and the use of nuruks (fermenting agent) affected the quality of the brown rice vinegar, and an appropriate method to consider its purpose is required.

• Food Science and Preservation
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• v.20 no.1
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• pp.69-75
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• 2013

This study was conducted to investigate the reliability of automatic cracked and bloody egg detector according to the age of the hens and the level of the detector. The results of this study are expected to be helpful in the implementation of the Korean egg grading system, which is expected to improve egg quality for consumers. An official egg grader randomly selected 1,000 eggs for each experiment (total 36,000 eggs), ran them through the automatic detector, and conducted labor inspection using the eggs that were classified by the detector as cracked, bloody, and normal eggs. The results showed that more cracked eggs were laid by hens aged 40-60 weeks than by hens aged 30 weeks (p<0.05). Also, when the detector level increased from four to seven (i.e., when it became less sensitive), its cracked eggs detection rate dropped, and the total rate of cracked eggs was consistent after the labor inspection of the classified eggs. The automatic detector achieved over 97 percent accuracy. The bloody eggs constituted only 0.005 percent of all the samples, and all the detector-detected eggs were bloody eggs after the labor inspection of both the bloody and normal egg lines. Therefore, it can be concluded that the automatic cracked and bloody egg detector was reliable and can be used in the egg grading system. Considering that cracked eggs should be less than 9 percent of first-grade eggs in the present egg grading system, the use of an automatic crack detector may help provide better-quality eggs to consumers by producing less than 5.5 percent cracked eggs.