• Restorative Dentistry and Endodontics
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• v.22 no.2
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• pp.693-701
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• 1997

In 1992, Prevotella intermedia was shown to be comprised of another spoecies now known as Prevotella nigrescens. Strain ATCC 33563 is now designated the type strain of P. nigrescens while strain ATCC 25611 is remains the type strain of P. intermedia. The purpose of this study was to find the differences in protein profiles of P. intermedia and P. nigrescens, using sodium dodecyl sulfate polyacrylamide gel electrophoresis, which can be used for differentiation of those two species. A partial amino acid sequence of the 18.6 kDa protein band, which was specific in P. nigrescens, was also determined. The cellular proteins were extracted from the cell pellets of pure cultures of P. intermedia. and P. nigrescens by either sonication or being shaken continuously for 20 min at $21^{\circ}C$ with 1 % SDS or being boiled for 3 min with 1 % SDS. SDS-PAGE was performed according to the method of laemmli using either 12% (w/v) gels or 18% (w/v) gels. Results were as follows ; 1. The similar electrophoretic protein profiles were shown by 3 cellular protein extraction methods for each strain. (Fig. 1 and 2) 2. the 18.6 kDa band which was specific only in P. nigrescens could be used for the differentiation of P. intermedia. and P. nigrescens. (Fig. 1 and 2, Table 1) 3. A total of 4 different tryptic fragments from the 18.6 kDa protein were sequenced. the resulting amino acid sequences were fragment 1.GNPVNIGGEW, 2.FNVVR, 3.NYLT-VAPY, and 4.GGDNVTTYQVLPEIGYN. By comparison to the sequences of known proteins in the Swiss-Prot database and PIR database. 90 % matching between fragment 1 and serine hydroxymethyl transferase(P24060) in the Swiss-Prot, and 90% matching between fragment 1 and glycine hydroxymethyl transferase(S15203) in the PIR were shown, but the identity and function of the 18.6 kDa protein remains unknown.

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.24-30
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• 2007

Inter simple sequence repeat (ISSR) markers were performed in order to analyse the genetic relation-ships of both taxa of Gardenia jasminoides var. radicans and G. jasminoides for. grandifora. Over the 88 fragments, only one locus (ISSR-11-05) was specific to G. jasminoides var. radicans and only one (ISSR-09-05) G. jasminoides for. grandiflora. Although G. jasminoides var. radicans showed low levels of alleles and Shannon's information index than G. jasminoides for. Grandiflora, however, there was not significant differences (p > 0.05). For both taxa the mean genetic diversity of natural populations was higher than that of cultivation populations. It was suggested that domestication processes via artificial selection do not have eroded the high levels of genetic diversity. ISSR markers were more effective in classifying natural populations of wild G. jasminoides in East Asia as well as cultivated G. jasminoides. The information about the phylogenetic relationship of G. jasminoides var. radicans and its closely related species is very valuable of the systematics of genus Gardenia, the origin of cultivated G. jasminoides, and future G. jasminoides breeding.

• Journal of Life Science
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• v.23 no.7
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• pp.847-853
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• 2013

The genus Hemerocallis (family Xanthorthoeaceae) is a herbaceous species, some of which are very important in herbal medicines. We evaluated the rps16-trnK region of the chloroplast DNA of a representative sample of eight taxa in Korea to estimate phylogenetic relationships within the taxa of this genus. Due to differences in the number of inserted nucleotides, the aligned data for Hemerocallis ranged from 729 (H. aurantiaca) to 742 nucleotides (H. fulva var. kwanso), with a mean of 736. Although several small indels and 20 inserts were present, sequence variation within the Hemerocallis genus was mostly due to nucleotide substitutions. All rps16-trnK trees generated in Korea exhibited a well-solved topology, with high bootstrap support, irrespective of the methods (parsimony) and the setting used. The node of H. minor and H. littorea was strongly supported, with a high bootstrap value in three trees, and these two taxa were sistered with H. thunbergii. The number of chromosomes was not congruent with that found in a previous study with RAPD, but the number was in agreement with the results of this study.

• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.446-453
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• 2009

RAPD analyses were performed to investigate genetic relationships and useful molecular maker for 3 species and their 17 regional populations of the Pueraria lobata and related taxa. The length of amplified DNA fragments ranged from 200 to, 2,800 bp. Two hundred and eight scorable polymorphic makers and three scorable monomorphic makers were found from the PCR reactions with 15 random oligo primers, and those were analyzed by Nei's genetic distance coefficient. Based on the UPGMA phenogram from RAPD analyses, two major groups (9 populations from Korea; 3 populations from foreign countries) were recognized. And it showed distinct genetic differences from related taxa. The RAPD results was very useful to define the samples by geographical distribution and to discuss the relationships among the populations and their related taxa of the Pueraria lobata.

• Ocean and Polar Research
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• v.38 no.1
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• pp.81-88
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• 2016

In many fish species, including Nile tilapia (Oreochromis niloticus), gonadal development occurs at the expense of stored energy and nutrients. Therefore, reproductive systems are inhibited by limited food supply. It has been well established that reproductive function is highly sensitive to both metabolic status and energy balance. Nothing is known about the possible mediated connection between energy balance and reproduction. Kisspeptin, a neuropeptide product of the Kiss gene has emerged as an essential gatekeeper of reproduction and may be possibly be linked to energy balance and reproduction in non-mammalians. Thus, in this study, the effect of fasting (10 days) on the expression of kisspeptin and the gonadotropin-releasing hormone (GnRH) gene were assessed in Nile tilapia (male and female) using qRT-PCR. In addition, plasma levels of estradiol-$17{\beta}$ ($E_2$) and 11-ketotestosterone (11-KT) in adult tilapia were measured by ELISA. In male tilapia, fasting reduced Kiss2 and GnRH I mRNA expression in the brain and 11-KT level in comparison with the fed tilapia (p < 0.05). In females, however, there were no significant differences in GnRH I mRNA expression and $E_2$ between fish subjected to fasting and those fed (p > 0.05). These data indicate the impact of nutritional states on kisspeptin as a potential regulatory mechanism for the control of reproduction in male Nile tilapia.

• Environmental and Resource Economics Review
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• v.19 no.2
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• pp.303-340
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• 2010

The Demilitarized Zone (DMZ) of Korea has been crucial not only for its buffering role between two Koreas, but also for the conservation of various resources across its premises. The objectives of this study is threefold. The first objective is to identify major resources that determine economic values of the DMZ and its vicinity. The second and third objectives are respectively to estimate conservation values of those resources using Choice Modeling and to test whether or not respondents living in different geographical locations have significantly different willingness to pay for the conservation. In a very conservative estimation, results showed that Korean adults have about 55,000 Won on average for conserving five major resources : the DMZ area, endangered species, cultural heritage items and sites, the Truce Village, and villages in the Civilian Conroal Zone. This equals the aggregate economic value of about 2,07 trillion Won. Moreover, significant regional differences were found in public benefits from conserving these major resources.

• Journal of Microbiology and Biotechnology
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• v.20 no.5
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• pp.925-934
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• 2010

Three typical biological solid wastes, namely, animal manure, garbage, and sewage sludge, were compared with regard to the composting process and the changes in microbial community structure. The effects of different bulking agents such as rice straw, vermiculite, sawdust, and waste paper were compared in manure compost. The differences in the microbial community were characterized by the quinone profile method. The highest mass reduction was found in garbage composting (56.8%), compared with manure and sludge (25% and 20.2%, respectively). A quinone content of $305.2\;{\mu}mol/kg$ was observed in the late stage of garbage composting, although the diversity index of the quinone profile was 9.7, lower than that in manure composting. The predominant quinone species was found to be MK-7, which corresponds to Gram-positive bacteria with a low G+C content, such as Bacillus. The predominance of MK-7 was especially found in the garbage and sludge composting process, and the increase in quinones with partially saturated long side-chains was shown in the late composting process of manure, which corresponded to the proliferation of Actinobacteria. The effects of different bulking agents on the composting process was much smaller than the effects of different raw materials. High organic matter content in the raw materials resulted in a higher microbial biomass and activity, which was connected to the high mass reduction rate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.654-660
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• 2003

To evaluate the biological diversity of fish pathogenic streptococci, 35 strains isolated from diseased olive flounder (Paralichtys olivaceus), were analyzed using a random amplified polymorphic DNA (RAPD) technique with the oligonucleotide commercial primer 6 (Amersham Biosciences). Api 20 Strep test, drug resistance and artificial infection were carried out for further characterization of the isolates. RAPD fingerprints showed similar pattern in 25 strains (about $71.4\%$ of 35 isolates) and these strains were designed as RA group 1. Similarities greater than $44\%$ were obtained when the Dice coefficient was applied among the isolates of RA 1. On the other hand, the reference Streptococcus iniae showed a similar RAPD profile to the isolates with similarity levels of $40-93.3\%.$ Rh I was suggested to be the dominant group isolated from olive flounder suffering from streptococcosis. However, the isolates of Rh 1 group were not classified into the same species by the Api 20 Strep identification system. There was no peculiarity in drug resistance patterns of Rh I group isolates against 7 antibacterial agents. However, only 3 of 25 isolates $(0.12\%)$ showed oxytetracycline (OTC) resistance and OTC might be a useful chemotherapeutic agent in controlling the streptococcosis by strains of RA I group in olive flounder. Fish injected intraperitoneally with $10^5$ CFU of an isolate of Rh I and RA III group showed $60\%\;and\;50\%$ accumulative mortality for 20 days, respectively ($20\%$ in control or Rh II). However luther comparative studies about differences in virulence between isolates are needed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.747-752
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• 2011

The parrotfish Oplegnathus fasciatus is a sub-tropical species that is difficult to culture during the winter in South Korea. As a result, a recirculating aquaculture system (RAS) was developed to rear parrotfish. This study investigated the effects of stocking density and dissolved oxygen (DO) concentration on the growth and hematology of the parrotfish in the RAS. The experimental stocking densities were 5 (SD05), 10 (SD10), 15 (SD15), and 20 kg/m3 (SD20) total body weight to tank water volume. As the stocking density increased, the mean weight gain, feed efficiency, and specific growth rate tended to decrease. However, SD10 and SD15 did not differ statistically from SD05 in feed efficiency (P>0.05). Although better growth was achieved in SD05, SD10 and SD15 appeared to be acceptable, practically and economically, in terms of feed efficiency. The experimental DO concentration ranges were 3-4 (DO3), 5-6 (DO5), and 7-8 mg/L (DO7). The mean weight gain and survival tended to increase with the DO concentration, but there were no differences among treatments (P>0.05). Although the feed efficiency did not differ among the treatments, the specific growth rates and daily feed intake increased with the DO concentration and were the highest in DO7 (P<0.05). The cortisol concentration was the highest in DO3 (P<0.05), while there was no difference between DO5 and DO7 (P>0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.574-578
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• 2001

Myofibrillar proteins were prepared from red muscle and white muscle of fresh water fish and sea water fish, and their thermostabilities and effect of temperature on the myofibrillar ATPase activities were compared. Differences in temperature dependency of myofibrillar ATPase activities were found between two species. Thermodynamic data for inactivation of myofibrillar proteins, such as D value, Z value, $\Delta$ $H^{{\neq}}$, $\Delta$ $G^{{\neq}}$ and $\Delta$ $S^{\neq}$ revealed that thermostabilities of myofibrillar proteins from fresh water fish were higher than those from sea water fish, and that myofibrillar proteins from red muscle were more heat labile than those from white muscle.