• Title/Summary/Keyword: Marine fisheries

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Deinococcus rubrus sp. nov., a Bacterium Isolated from Antarctic Coastal Sea Water

  • Srinivasan, Sathiyaraj;Lim, Sangyong;Lim, Jae-Hyun;Jung, Hee-Young;Kim, Myung Kyum
    • Journal of Microbiology and Biotechnology
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    • v.27 no.3
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    • pp.535-541
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    • 2017
  • Two Gram-staining-negative, red-pinkish, coccus-shaped, non-motile, and aerobic bacterial strains, designated $Ant21^T$ and Ant22, were isolated from the Antarctic coastal sea water. Strains $Ant21^T$ and Ant22 showed UVC and gamma radiation resistance. Phylogenetic analyses based on 16S rRNA gene sequences determined that these strains belong to the genus Deinococcus. Through the analyses of the 16S rRNA gene sequences, strains $Ant21^T$ and Ant22 were found to have 97.7% and 97.8% similarity to Deinococcus marmoris DSM $12784^T$ and 97.0% and 97.2% similarity to Deinococcus saxicola AA-$1444^T$, respectively. The sequence similarity with the type strains of other Deinococcus species was less than 96.9% for both strains. Strains $Ant21^T$ and Ant22 shared relatively high 16S rRNA gene sequence similarity (99.3%) and had a closely related DNA reassociation value of $84{\pm}0.5%$. Meanwhile, they showed a low level of DNA-DNA hybridization (<30%) with other closely related species of the genus Deinococcus. The two strains also showed typical chemotaxonomic features for the genus Deinococcus, in terms of the major polar lipid (phosphoglycolipid) and the major fatty acids ($C_{16:0}$, $C_{16:1}$ ${\omega}6c/{\omega}7c$, $iso-C_{17:0}$, and $iso-C_{15:0}$). They grew at temperatures between $4^{\circ}C$ and $30^{\circ}C$ and at pH values of 6.0-8.0. Based on the physiological characteristics, the 16S rRNA gene sequence analysis results, and the low DNA-DNA reassociation level with Deionococcus marmoris, strains $Ant21^T$ ($=KEMB\;9004-167^T$ $=JCM\;31436^T$) and Ant22 (KEMB 9004-168 =JCM 31437) represent novel species belonging to the genus Deinococcus, for which the name Deinococcus rubrus is proposed.

Incubation Time Required for Hatching, and Ecological Characteristics of the Mode of Life Related with Total Numbers of the Suckers on Each Short Arm of the Hatched Juvenile Larvae of Octopus ocellatus (Cephallopoda: Octopodidae), in Western Korea

  • Kim, Sung Han;Jun, Je-Cheon
    • The Korean Journal of Malacology
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    • v.32 no.2
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    • pp.133-139
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    • 2016
  • The incubation time required for hatching of O. ocellatus were investigated through the processes of egg and embryonic developments by the dissecting microscopic and visual observations. And differences in ecological characteristics of the plankton mode of life or the benthic mode of life according to total numbers of the suckers on each short arm of the hatched juvenile larvae of O. ocellatus were studied by comparisons with other octopodidae species. Compared with the recent a few results reported by other researchers associated with the incubation time required for hatching by female adult mother of O. minor (73-90 days after spawning at $20.9-21.5^{\circ}C$ ranges), in this study, the incubation time required for hatching by female adult mother of O. ocellatus was 56-57 days after spawning at $11.0-20.4^{\circ}C$. Therefore, the incubation time required for hatching by female adult mother varied with Octopodidae species. In this studies, each ovarian egg laid by a female was connected to an egg string attaching to the surface of the wall or bottom of vacunt shell of Rapana venosa. Egg and embryonic developments of this species were studied in the indoor aquaria, in the specific gravity ranging 1.024-1.025. the hatched juvenile of O. ocellatus is 10.3 mm in the mean total length and 4.5 mm in mantle length, and each of its short arms has 18-20 suckers. The just hatched juvenile larvae of O. ocellatus enter the benthic mode of life (benthic larval stage) after hatching. In particular, regarding differences in ecological characteristics of the mode of life according to total numbers of the suckers, O. vulgaris may not need to have many suckers because they enter the planktonic mode of life after hatching, however O. ocellatus may need to have many suckers, because they should adapt to the benthic mode of life. And also the just hatched juvenile larvae of O. minor (bearing many suckers more than O. ocellatus) enter the benthic mode of life (benthic larval stage) after hatching. Therefore, the total number of the suckers on each short arm of the hatched juvenile larvae can be used for determining whether an octopus species has planktonic larval stages or benthic larval stage (benthic mode of life). In particular, The intracohort cannibalism phenomena appeared at the hatched juvenile larval stage because the larval stage of O. ocellatus and O. minor enter into the benthic larval stage in the early stage, unlike entering into the plaktonic larval stage in other Octopus species such as O. vulgaris: at this time, the early hatched larvae fed the late hatched larvae (they are the same species and almost same ages). Therefore, the intracohort cannibalism pheneomena occur in the just hatched juvenile stage of only O. ocellatus and O. minor.

Deposition Characteristics of Atmospheric PCBs Depending on Exposure Periods Using Pine Needles (소나무 잎을 이용한 대기 중 PCBs의 노출기간별 침착특성)

  • Yeo, Hyun-Gu;Cho, Ki-Chul;Choi, Min-Kyu;Kim, Tae-Wook;Chun, Man-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.8
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    • pp.836-842
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    • 2006
  • Pine needle samples(1 year, 2 year, 3 year old) were collected in Seoul and Ansung to investigate the deposition characteristics of atmospheric PCBs depending on exposure periods. Total PCBs concentration of pine needle samples in Seoul and Ansung showed 2,429, 1,198 pg/g DW(dry weight), respectively. PCB homologs concentration of pine needle samples decreased with increasing chlorine-substituted compounds. It showed that higher chlorine- substituted compounds in existing particle phase compared to lower chlorine-substituted compounds existing in gaseous phase were difficult to accumulate lipids of the pine needles samples. The results of regression analysis between exposure periods in the atmosphere and concentration of total PCBs measured in pine needles at two sites showed significant levels($R^2>0.94$, p<0.01), which implies that atmospheric PCBs accumulated on pine needles with positive linearity depending on exposure periods in this study. Therefore pine needle samples can be used as passive air sampler(PAS) for monitoring air contamination for a long time in different sites.

Copper Toxicity on Survival, Respiration and Organ Structure of Mactra veneriformis (Bivalvia: Mactridae) (동죽, Mactra veneriformis의 생존, 호흡 및 기관계 구조에 미치는 구리 (Cu)의 독성)

  • Shin, Yun Kyung;Park, Jung Jun;Lim, Hyun Sig;Lee, Jung Sick
    • The Korean Journal of Malacology
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    • v.29 no.2
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    • pp.129-137
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    • 2013
  • This study was conducted to find out the changes of survivorship, respiration and organ structure of Mactra veneriformis exposed to copper (Cu). Experimental period was four weeks. Experimental groups were composed of one control condition and three copper exposure conditions (0.025, 0.050 and 0.100 mg/L). The results of the study confirmed that copper induces reduction of survival rate and respiration rate and histopathology of organ structure of the bivalve. In the copper concentration of 0.100 mg/L, mortality was 100% after Cu exposure of 3 weeks. Respiration rate was observed exposure groups lower than control decline by 75%. Histological analysis of organ system illustrated expansion of hemolymph sinus, disappearance of epidermal layer and degeneration of connective tissue layer of the mantle. Also, histological degenerations as epithelial necrosis and hyperplasia of mucous cells are recognized in the gill and it was observed expansion of hemolymph sinus, disruption of epithelial layer, decrease of mucous cell and degeneration of connective tissue layer in the foot. In the digestive diverticulum, it was showed atrophy of basophilic cell and degeneration of epithelial cell in the digestive tubules, and as the concentration of copper increased the accumulation of lipofuscin increased.

Early Developmental Characteristics of Induced Hybrids between Rhodeus uyekii and R. notatus (Pisces: Cyprinidae) (각시붕어(Rhodeus uyekii)와 떡납줄갱이(R. notatus) (Pisces: Cyprinidae) 잡종의 초기 발생 특징)

  • Kang, Eon-Jong;Kim, Chi-Hong;Park, In-Seok;Yang, Hyun;Cho, Yong-Cheol
    • Korean Journal of Ichthyology
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    • v.18 no.4
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    • pp.339-346
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    • 2006
  • In this study we conducted artificial hybridization between two sibling species, Rhodeus uyekii and R. notatus, and observed the morphological characteristics in early developmental stage. The two species showed difference in egg shape having rhombus and club respectively. The morphology of yolk of larva just hatched also showed well specific characteristics, that is the bean chaff type for R. uyekii (U type) and anchor type for R. notatus (N type). The rate of fertilization between female R. uyekii and male R. notatus (UN type) and between female R. notatus and male R. uyekii (NU type) were complete and its hatching rate were very high, 71.6% for UN type and 97.5% for NU type. The differences occurred in the yolk shape of hatched larvae for each combination of hybrids. In the group of UN, U type of larvae were found very rarely, but almost all the larvae showed intermediate shape polarized to NN type. Similar phenomenon was observed in the NU having intermediate polarized to UU, but without any NN type. These hybrids will be analyzed for their external morphology, sex ratio, the function of sexual organ and karyology after they grown up to adult.

Effects of Photoperiod and Water Temperature on the Reproductive cycle of the Spring-Spawning Bitterling, Rhodeus uyekii (Pisces : Cyprinidae) (각시붕어, Rhodeus uyekii의 생식주기에 미치는 광주기 및 수온의 영향)

  • An, Cheul-Min
    • Korean Journal of Ichthyology
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    • v.7 no.1
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    • pp.43-55
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    • 1995
  • Based on the reproductive cycle of Rhodeus uyekii, the reproductive control mechanism was examined under the several combinations of photoperiod and temperature regimes at different phases of their reproductive cycle. In early spring, the gonads developed rapidly under the warm temperature condition(above $8^{\circ}C$), regardless of the photoperiod. In late spring or early summer, gonads intensely regressed under the high temperature condition(above $24^{\circ}C$), regardless of the photoperiod. Thus, it is concluded that the spawning period of R. uyekii is initiated by the rising of water temperature in spring and is terminated by the high temperature in early summer. In autumn, the gonadal recrudescence occurs under the conditions of artificial long daylength with warm temperature(15L/9D, $12^{\circ}C{\sim}20^{\circ}C$), whereas the gonads remain in the existing condition under the short daylength. Therefore, in autumn the gonadal recrudescence is prevented by the short daylength although the temperature is still in favorable condition. In bitterling, the responsiveness of the gonads to photoperiod varies clearly with seasons, which was declined during the winter but increased during the autumn. The critical photoperiod for maturation ranges 12~13 hours of light per day. The results indicate that the proper ranges of temperature and photoperiod for gonadal maturation of this species are from $8^{\circ}C$ to $8^{\circ}C$ and from 13L to 15L, respectively.

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The Occurrences of Pharmaceutical and Personal Care Products (PPCPs) in Mankyung River, South Korea (만경강 수중에서 신체보초제품(PPCPS)의 잔류)

  • Kim, Joon-Woo;Kim, Jong-Gu;Jang, Hyo-Sang;Cho, Hyeon-Seo;Takao, Yuji;Arizono, Koji
    • Journal of Environmental Science International
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    • v.18 no.3
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    • pp.245-254
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    • 2009
  • In recent years, environmental pollution by phannaceuticals and personal care products (PPCPs) in the aquatic environment is of great concern worldwide. Recent studies have been reported to occur in a variety of environmental organisms such as surface, drinking and ground water, soils, sediments and hospitals. The purpose of this study was to evaluate the occurrence and environmental behavior of fourteen human PPCPs in surface waters of Mankyung River in South Korea. We were conducted to field survey for water quality and PPCPs analysis at November, 2006. PPCPs were analyzed by liquid chromatograph coupled with a tandem mass spectrometer (HPLC-MS/MS). The concentration of COD was measured to be 2.37$\sim$19.71 mg/L, which was belong to 4$\sim$5 grade in water quality criteria of lake. Station 2 that there is no pollution in upper stream, was appeared to lower concentration. The concentration of TN and TP, that is cause matter of eutrophication, were found to be 7.78$\sim$35.42 mg/L and 0.08$\sim$0.95 mg/L, respectively, which were exceeding 5 grade in Lake water quality criteria. The 11 kind of PPCPs compounds except levofloxacin and triclosan were detected to Mankyung river. PPCPs concentrations of STP(Sewer Treatment Plant) effluents and aquatic environment in Mankyung river have been detected in the range from dozens of ng/L to hundreds of ${\mu}g/L$ that by order of atenolol, carbamazepine, propranolol, Ibuprofen, erythromycin, ifenprodil, clarithromycin, mefenamic acid, fluconazole, indomethacin, disopyramide. PPCPs concentration of Station 1 and 5, which was influenced by Jeonju STP and Wanju STP, was detected high values. Station 2 that there is no pollution, showed lower values. Station 3 which joined Gosan stream and Jeonju stream and station 4 which influenced by stock wastewater was detected to low values.

Uncoupling Protein 3 in the Rainbow Trout, Oncorhynchus mykiss Sequence, Splicing Variants, and Association with the AvaIII SINE element

  • Kim, Soon-Hag;Choi, Cheol-Young;Hwang, Joo-Yeon;Kim, Young-Youl;Park, Chan;Oh, Berm-Seok;Kimm, Ku-Chan;Scott A. Gahr;Sohn, Young-Chang
    • Journal of Aquaculture
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    • v.17 no.1
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    • pp.1-7
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    • 2004
  • A rainbow trout uncoupling protein 3 (UCP3) cDNA clone, encoding a 310 amino acid protein, was cloned and sequenced from a liver cDNA library. Two different splice variants designated UCP3-vl and UCP3-v2, were identified through liver cDNA library screening using rainbow trout UCP3 cDNA clone as a probe. UCP3-vl has 3 insertions in the UCP3 cDNA: the first insertion (133 bp), the second (141 bp), and the third (370 bp) were located 126 bp, 334 bp and 532 bp downstream from the start codon, respectively. UCP3-v2 contained a single insertion, identical in sequence and location to the second insertion of UCP3-vl. UCP3, a mitochondrial protein, functions to modulate the efficiency of oxidative phosphorylation. UCP3 has been detected from heart, testis, spinal cord, eye, retina, colon, muscle, brown adipose tissue and white adipose tissue in mammalian animals. Human and rodent UCP3s are highly expressed in skeletal muscle and brown adipose tissue, while they show weak expression of UCP3 in heart and white adipose tissue. In contrast to mammalian studies, RT-PCR and Southern blot analysis of the rainbow trout demonstrated that UCP3 is strongly expressed in liver and heart. UCP3, UCP3-vl, and UCP3-v2 all contain an Ava III short interspersed element (SINE), located in the 3'untraslated region (UTR). PCR using primers from the Ava III SINE and the UCP3 3'UTR region indicates that the UCP3 cDNA is structurally conserved among salmonids and that these primers may be useful for salmonid species genotyping.

Effect of Heat Treatment on High Temperature Fatigue Strength Characteristics of STB2 Bearing Steel (STB2강의 고온피로강도 특성에 미치는 열처리의 영향)

  • Oh, Sae-Kyoo;Kim, Yeon-Ho;Lee, Sang-Guk;Lee, Jong-Du
    • Journal of Ocean Engineering and Technology
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    • v.3 no.2
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    • pp.638-638
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    • 1989
  • It has been very important in various industry fields to improve the fatigue strength characteristics of bearings such as bearing life, fatigue limit, etc., because such poor properties could result in shortening the machinery life as well as in decreasing the accuracy. However, no successful heat treatment criterion seems to be available at present. In this study, the effect of the $170^{\circ}C\times120min$ tempering cycles repeated after $380^{\circ}C\times80min$ oil quenching for $800^{\circ}C$ spheroidizing-annealed bearing steel (STB2) as base metal on the $120^{\circ}C$ high temperature rotary bending fatigue strength characteristics were investigated, including the effects on hardness, Charpy impact value and micro-structure, in order to seek for the best heat treatment condition finally. The important results obtained are as follows : 1) The optimal cycle of tempering so that the fatigue strength .sigma. could become the highest was the 4th cycle. And it is confirmed that this $\sigma_{F}$ is about 6 times more increased than that of base metal, and about 1.3 times more increased than the case of the 1 cycle tempered. 2) As a result of the investigation for the effects of tempering cycles on hardness, the hardness at the tempering number of 2 thru 5 cyles was not decreased severely ; only about 10% decrease from those of the quenched and 1 cycle tempered case. Such hardness is equivalent to $H_{R}$/C61-62 with no bad effect on anti-abrasion of bearing steel. 3) In the case of 2 thru 5 cycle tempering as well as 1 cycle tempering, the impact value was not so improved comparing with the case of quenching, but an increase of 5 to 10% could be expected at least. 4) It was experimentally confirmed that the control of the mechanical properties improvement such as fatigue strength and fatigue life for bearing steels could be possible by the number of tempering cycles.

Isolation and Characterization of Paramyosins of Marine Gastropods (해산복족류(海産腹足類)의 Paramyosin의 분리(分離) 및 그 특성(特性)에 관(關)한 연구(硏究))

  • Pyeun, Jae-Hyeung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.2 no.1
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    • pp.1-21
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    • 1973
  • The muscle of abalone, Notohaliotis discus (REEVE), and top-shell, Turbo cornutus Solander, were examined for protein composition. Then paramyosins which are known as one of the important structural protein of the muscle fibrils were isolated from the both muscle and their physico-chemical properties such as solubility, salting-out behaviour, intrinsic viscosity, ATPase activity, etc. involving amino acid composition and N-terminal amino acid residues were investigated to elucidate phylogenie characteristics more intensively from the viewpoint of comparative biochemistry. The analysis of protein composition resulted in the following estimations: abalone muscle; water-soluble protein of 22 %, salt-soluble protein, 34%, alkali-soluble protein, 20%, and stroma protein, 24%, and top-shell muscle; water-soluble protein of 16%, salt-soluble protein, 30%, alkali-soluble protein, 29%, and stroma protein, 25%, respectively. It is demonstrated in sedimentation analysis that paramyosin and myosin-actomyosin account for approximately 65% and 35% of the salt-soluble protein of abalone, and that the composition of both sediments in top-shell was approximately 70% and 30%, respectively. The ultracentrifugally homogenous paramyosins isolated essentially according to Bailey's ethanol-dried method from both of the muscle showed a $S^{\circ}_{20,w}$ of 3. 14s for abalone and a $S^{\circ}_{20,w}$ of 3.50s for top-shell. The both paramyosins were commonly rich in arginine, aspartic acid, and glutamic acid, while scarcely contained proline and tryptophan, in rough accord with the other paramyosins thus far reported. It is clear that these gastropod paramyosins showed of having the characteristic N-terminal amino acid residues such as N-aspartic acid, N-valine, N-serine, and N-threonine in common. The abalone paramyosin completely salted in with KCl beyond $0.35{\mu}$ and the top-shell paramyosin beyond $0.30{\mu}$. The abalone paramyosin was salted-out between 18% and 30% saturation of ammonium sulphate and the top-shell paramyosin between 22% and 29% saturation. The intrinsic viscosities at abalone and top-shell paramyosins at $25^{\circ}C$ were estimated respectively to be 3.1 dl/g and 2.6 dl/g showing somewhat higher than the values for some other paramyosins from lamellibranchs. In regard with the ATPase activity, the para myosin specimens did not exhibit any significant activity over through the pH conditions of 5 to 9.5. irrespective of the presence of $Ca^{++}$ or $Mg^{++}$. So was the case with the abalone paramyosin prepared by a slightly modified Bailey's wet-extraction method.

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