• 한국수산과학회지
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• 제45권1호
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• pp.76-81
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• 2012

The feeding habits of daggertooth pike conger Muraenesox cinereus were studied using 380 specimens collected in the coastal waters off Goseong, Korea, from June to September, 2011. The M. cinereus ranged from 10.0-23.7 cm in anal length (AL). M. cinereus is a piscivore that consumes mainly fish. Engraulis japonicus was the preferred prey, but its diet also included small numbers of crabs, shrimps, cephalopods, and bivalves. The feeding strategy graphical method revealed that M. cinereus is a specialized feeder with a narrow niche width. All size classes of M. cinereus consumed fish and M. cinereus did not show significant ontogenetic changes in feeding habits. The diet overlap index between size classes was >0.96, indicating high diet similarities. The prey size increased significantly with M. cinereus size.

• 한국수산과학회지
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• 제53권1호
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• pp.98-102
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• 2020

We examined the comparative spawning ecology of daggertooth pike conger Mureanesox cinereus and common pike conger M. bagio in the South Sea of Korea from May 2018 to December 2019. In the South Sea of Korea, the mean total length (TL) of M. cinereus was significantly smaller than that of M. bagio. The sex ratios of both species were skewed toward females. The spawning period of M. cinereus was from June to October, while the spawning period of M. bagio was from August to October. The lengths at 50%, 75%, and 97.5% sexual maturity of M. cinereus females were estimated as 54.6 cm, 60.4 cm, and 74.1 cm TL, respectively. It was not possible to estimate lengths at sexual maturity for M. bagio in the South Sea of Korea due to the absence of immature stages.

• 한국수산과학회지
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• 제52권2호
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• pp.173-179
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• 2019

We investigated the ecological characteristics and proximate composition of Muraenesox cinereus off the southern coast of Korea. Anal length distribution, sex ratio, condition factor of M. cinereus individuals caught by costal complex (longline) fisheries were investigated from June to October 2018. The mean anal length was 23.5 cm, which was less than $L_{50}$, indicating that the individuals were mostly immature. Sex ratio is 9:1, we captured 382 females and 29 males, which produced a significantly different ratio (P<0.05). Condition factor remained constant over the study period. The proximate composition of M. cinereus individuals was analyzed from July to October 2018. No significant differences in moisture, crude lipid, crude protein, and ash content were observed between individuals caught in summer and those caught in fall.

• 한국수산과학회지
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• 제52권6호
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• pp.650-655
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• 2019

The age and growth of Muraenesox cinereus collected in the South Sea of Korea by Danish seine and coastal Long-line fisheries were determined from right sagittal otoliths between May 2018 and April 2019. Otoliths of 353 fish were observed under reflected light, and the edges of the opaque zone were considered to be the otolith ring. Monthly changes in the marginal index indicated that rings (opaque zones) were formed once a year from June to July. The estimated von Bertalanffy growth equation with growth parameters estimated from non-linear regression were L_t=138.37 (1-e^{-0.18(t+0.79)}) for females and L_t=99.00 (1-e^{-0.13(t+3.99)}) for males. The oldest female M. cinereus was 12 years old, and the oldest male was 8 years old.

• 수산해양기술연구
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• 제54권4호
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• pp.353-359
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• 2018

Basic reproductive biology of the daggertooth pike conger, Muraenesox cinereus were investigated based on the samples from August 2015 to December 2017 in Korean waters. A total of 2,328 samples was collected (1,593 females and 735 males) during the study period. The mean anal lengths (AL) were $33.5{\pm}9.2cm$ in females and $26.2{\pm}7.3cm$ in males respectively. The females were larger than males in AL (p < 0.05). Sex ratio was 2.2:1 in female to male (p < 0.05). The gonadosomatic index (GSI) varied monthly. GSI of female reached the maximum in July 2016 and June 2017 and the minimum in October 2016 and September 2017 respectively. The spawning period was from June to October. The size at sexual maturity ($L_{50}$) of females was estimated at 24.9 cm in AL (63.5 cm in TL).

• 한국발생생물학회지:발생과생식
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• 제19권3호
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• pp.163-166
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• 2015

Genomic DNAs were extracted from the muscle of twenty-one specimens of three eel species collected in Anguilla japonica (AJ), Muraenesox cinereus (MC) and Conger myriaster (CM) from the Yellow Sea, respectively. In the present study, 7 oligonucleotides primers generated 191 specific loci in the AJ species, 226 in the (MC) species and 181 in the CM species, respectively. The primer BION-02 generated the most loci (a total of 83), with an average of 11.86 in the AJ species. The specific loci generated by oligonucleotides primers exhibited inter-individual-specific characteristics, thus revealing DNA polymorphisms. With regard to average bandsharing value (BS) results, individuals from Conger myriaster species (0.808) exhibited higher bandsharing values than did individuals from Muraenesox cinereus species (0.729) (P<0.05). The longest genetic distance (0.430) displaying significant molecular difference was also between individual no. 01 within Anguilla japonica eel species and individual no. 04 within Anguilla japonica species. In this study, the dendrogram resulted from reliable seven oligonucleotides primers, indicating three genetic clusters composed of group I (ANGUILLA 01~ANGUILLA 07), group II (MURAENESOX 08~MURAENESOX 14) and group III (CONGER 15~CONGER 21). The existence of species differentiation and DNA polymorphisms among three eel species were detected by PCR analysis. As mentioned above, a dendrogram revealed close relationships between individual identities within three eel species. High levels of a significant genetic distance among three eel species showed this PCR approach is one of the most suitable tools for individuals and/or species biological DNA studies.

• 생명과학회지
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• 제29권2호
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• pp.248-255
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• 2019

국내 삼천포 및 서천에서 채집한 갯장어(Muraenesox cinereus)의 장내기관으로부터 분리된 미생물들의 다양성 및 특성에 관하여 조사하였다. 장내 미생물의 순수 분리를 위하여 marine agar 배지를 사용하였으며 $37^{\circ}C$에서 호기적으로 배양하였다. 순수 분리 후, 49 균주를 분리하였으며 16S rRNA 염기서열 분석 결과를 바탕으로 계통학적 분석을 실시한 결과, 3문, 13과, 14속, 34종으로 구성되어 있는 것을 확인하였다. 특히, Proteobacteria 문은 83.7%의 분포를 나타내었으며 8과, 8속, 26종으로 Aeromonadaceae, Pseudoalteromonadaceae, Shewanellaceae, Enterobacteriaceae, Morganellaceae, Moraxellaceae, Pseudomonadaceae와 Vibrionaceae로 분포하는 것을 확인하였다. 그리고 분리한 균주들이 amylase, lipase, protease와 같은 산업적으로 유용한 효소를 생산하는지 확인하기 위하여 효소 활성 평가를 실시하였으며, 39 균주가 최소 한 종류 이상의 효소 활성을 가지고 있는 것을 확인하였다. 특히 Aeromonas 속의 균주들은 테스트한 모든 효소의 활성을 나타내는 것을 확인하였다. 이러한 결과는 본 연구를 통하여 분리한 미생물들의 산업적 활용 가능성을 나타내었다. 그러므로 이번 연구는 국내 유전자원 확보 및 갯장어의 장내마이크로비옴의 과학적 지식 확장에 도움이 될 것으로 생각된다.

• 수산해양기술연구
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• 제56권4호
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• pp.292-298
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• 2020

The effects on the size selectivity for Muraenesox cinereus caught by coastal longline fishery were investigated in the southern coast of Korea from June 2 to 17, 2019. Four sizes of hooks (sizes 15, 17, 18 and 19) and two sizes of bait (sizes 9.9 g and 18.3 g) were tested in seven and three fishing trials, respectively. Such results revealed that smaller hook and bait size improved capture efficiency. And our results demonstrate that there was no significant size selectivity effect for hook size (ANOVA, p>0.05), but small bait improved on catching smaller fish (ANOVA, p<0.05).

• KSBB Journal
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• 제26권1호
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• pp.27-32
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• 2011

For the development of functional food and cosmetics using hot water extract of Muraenesox cinereus's skin, contents of vitamin, amino acid and element, and antioxidant activity were investigated. The results are shown as follows: among vitamins, A(0.21mg/100 g), C (78.12mg/100 g), $D_3$ (0.03 mg/100 g), E (1.97 mg/100 g) and Niacin (2.53mg/100 g) were detected, respectively.Mineral contents were an order of K > P > Na > Mg > Ca > Fe and Zn. Contents of total amino acids were an order of Pro > Gly > Arg > Glu > Phe > Ala. Especially, the sum of total amino acids was 27.17 mg/100 mL, which was about 4.0 fold higher than that of free amino acid. DPPH radical scavenging activity of hot water extract of M. cinereus's skin at 25 mg/mL was 63.5% and did not increase at above 50 mg/mL. Activities of antioxidant enzymes in the liver of ethanol-treated rats using hot water extract of M. cinereus's skin were investigated. Compared to control group, activities of ADH and GSH-px were decreased. In the case of CAT and SOD activity, they were increased. These results showed that the hot water extract of M. cinereus's skin can be applied to raw macterial for functional food and cosmetics.

• KSBB Journal
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• 제26권3호
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• pp.260-265
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• 2011

This study aimed to examine the treatment effect of Muraenesox cinereus extract product combined with high frequency on men's damaged skin. The subjects were treated by a product containing M. cinereus extract combined with high frequency therapy for six weeks and tested in skin condition. First, for moisture level change, there was no significant difference between the control group treated only by high frequency therapy and the experimental group treated by a M. cinereus extract product combined with high frequency therapy. But the subjects who increased consistently in moisture level in the cheek and chin were more common in the experimental group. Second, for an oil level, prominently high increase was found in both the control group and the experimental group. Finally, for a rough level, while there was little difference in the control group between immediately after peeling and after six weeks, high improvement effect on a curve was found in the experimental group. Based on this result, cosmetics using M. cinereus extract may have a positive effect on men's skin which is exposed to several stress factors. Accordingly, this result will contribute to developing men's functional cosmetics.