• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.3
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• pp.448-453
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• 2015

This study was performed to estimate biomass and to provide management plan through population ecological characteristics, including survival rate, instantaneous coefficient of natural and fishing mortalities, and age at first capture of Flathead grey mullet, Mugil cephalus, in the coastal waters of Yeosu. Survival rate (S) of the flathead grey mullet was 3.671. The instantaneous coefficients of natural mortality (M) and fishing mortality (F) was estimated to be 0.325/year, 0.962/year for flathead grey mullet. Also fist capure age of flathead grey mullet was 3.61year. The current biomass of the flathead grey mullet in the study area was estimated to be 19.6 M/T and $F_{0.1}$ and $F_{40%}$ were estimated 0.340/year, 0.225/year. For the stock assessment result, flathead grey mullet was not overfished but overfishing.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.3
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• pp.203-213
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• 2011

The age and growth of flathead grey mullet, Mugil cephalus, were studied using samples collected from the coastal water of Yeosu from September 2009 to August 2010. Spawning season estimated from the gonadosometic index (GSI) was from November to January. A method for increasing the readability of the otolith was described and criteria for the interpretation of otolith was provided. The annual ring was formed in September once a year. Annual ring in otolith for flathead grey mullet is validated for fish aged 1-8 using the marginal increment analysis. Using the sectioned otolith, between reader precision was 84%. Also, Within-reader agreement for sectioned otolith age readings was higher (reader 1=84%, reader 2=87%). The relationship between fork length and total weight was TW=$0.022FL^{2.818}$. The estimated von Bertalanffy growth parameters for the flathead grey mullet were $L_{\infty}$=67.97cm K=0.164/year and $t_o$=-0.81year.

• Korean journal of food and cookery science
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• v.14 no.3
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• pp.255-260
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• 1998

The changes in fatty acids and free amino acids of raw and salted-dried flatheads were determined during steaming, boiling and baking process. 1. Raw flathead was composed of 74.9% of moisture, 1.9% of ash, 0.9% of crude lipid, and 21.6% of crude protein. 2. The main fatty acids of raw and salted-dried flathead were palmitic acid (21.5%) and lignoceric acid (52.4%) which covered 73.9% of total fatty acid. The fatty acid contents of raw and salted-dried flathead were higher in the steaming than in the boiling and baking. 3. The main free amino acids of .aw and salted-dried flathead were aspartic acid (12.2%), glutamic acid(14.8%), leuicine (8.4%), Iysine (9.8%) and arginine (6.8%), which covered 52% of total free amino acids. There were significant differences (p<0.05) in the contents of free amino acids between raw and salted-dried flatheads as well as among steaming, boiling and baking processes.

• Korean journal of food and cookery science
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• v.15 no.5
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• pp.512-523
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• 1999

A purpose of this study was to figure out the best cooking conditions of salted-dried fish by a sensory evaluation on cooked salted-dried flathead. Cooking of the salted-dried fish is traditional and popular in Korea, and salted-dried flathead is a favorite with southern Korea. The raw material for the examination were a raw flathead and 3 degrees salted(2%, 4%, 6%)-dried flathead which added 3 kinds cooking treatment (steaming, boiling, baking) within three different times(5, 10 and 15 min.) respectively. The category scaled descriptive test and response surface methodology were applied for the evaluation, and the results of the evaluation were analyzed by SAS program. The result of the study were as follows : 1. For the steaming cooking, scale at 6% salt concentration and 5 minutes cooking time were the best conditions of the salted-dried flathead cooking. 2. For the boiling, 6% salt concentration and 10 minutes cooking time were the best conditions. 3. For the baking, 6% salt concentration and 10 minutes cooking time were the best conditions. 4. The baking group got higher estimations on the items of browning, cooked condition and meaty aroma than steaming and boiling group on Duncan's multiple range test. According to the result of the Duncan's test, baking is better cooking way for the salted-dried flathead.

• Korean Journal of Ichthyology
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• v.33 no.4
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• pp.217-225
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• 2021

The family Platycephalidae is a taxonomic group of economically important demersal flathead fishes that predominantly occupy tropical or temperate estuaries and coastal environments of the Indo-Pacific oceans and the Mediterranean Sea. In this study, we for the first time analyzed the complete mitochondrial genome (mitogenome) of the flathead Platycephalus cultellatus Richardson, 1846 from Vietnam by Next Generation Sequencing method. Its mitogenome was 16,641 bp in total length, comprising 13 protein-coding genes (PCGs), two ribosomal RNA genes, and 22 transfer RNA genes. The gene composition and order of the mitogenome were identical to those of typical vertebrates. The phylogenetic trees were reconstructed based on the concatenated nucleotide sequence matrix of 13 PCGs and the partial sequence of a DNA barcoding marker, cox1 in order to determine its molecular phylogenetic position among the order Scorpaeniformes. The phylogenetic result revealed that P. cultellatus formed a monophyletic group with species belonging to the same family and consistently clustered with one nominal species, P. indicus, and two Platycephalus sp. specimens. Besides, the cox1 tree confirmed the taxonomic validity of our specimen by forming a monophyletic clade with its conspecific specimens. The mitogenome of P. cultellatus analyzed in this study will contribute valuable information for further study on taxonomy and phylogeny of flatheads.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.521-529
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• 2000

The purpose of this study was to determine the best cooking condition for salted-dried flathead by sensory evaluation. Raw flathead and 3 different kinds of salted(2%, 4%, 6%)-dried flathead were cooked by various methods such as steaming, boiling, baking and different cooking times(5, 10, and 15min). The results of this study were as follows: 1. In steamed samples, the meaty flavor was significantly related with brown color, cooled level, and softness at 5% level. 2. In boiled samples, meaty flavor was significantly related with cooked level, moistness, and fishy odor at 5% level. 3. For broiled samples, meaty flavor was significantly related with fishy odor, meaty aroma, and bitter taste at 1% level. 4. The best cooking conditions determined by a quantitative descriptive analysis(QDA) were steaming 6% salted-dried samples for 5min, and boiling or broiling 6% salted-dried samples for 10min. The most favored cooking method was broiling. 5. In comparison of the samples by QDA, 2% salted-dried samples cooked 15 min gave better scores in the order of boiled > overall score > steamed > broiled, 4% samples cooked 5min were boiled > steamed > overall score > broiled, and 6% samples showed similar scores among all conditions. The 6% samples cooked for 5min gave high scores in 7 terms of QDA in steaming, and 6% samples cooked for 10min for boiled and baked.

• Korean Journal of Ichthyology
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• v.26 no.3
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• pp.194-201
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• 2014

Age and growth of flathead grey mullet Mugil cephalus were estimated using samples collected by a two-side fyke net in the coastal water off Taean in 2008. Age was determined by examination of annuli in otoliths and total lengths at ages were back-calculated from otolth-body size relationship. Total length ranged from 239 to 605 mm and mainly between 400 and 550 mm. Observed ages ranged from 1 to 7 years old and mainly between 3 and 5 years old. Total length (L, mm) was linearly related to otolith radius (R, mm); L=15.3+87.9 R. Total lengths at the annulus formation in otolith were back-calculated by Frazer-Lee method. Estimated length at the age 1 was $316{\pm}40.6mm$ ($mean{\pm}SD$) showing a fast growth rate during the early growth stage. Total length at each age (t) showed a wide range indicating the big difference in growth rate among individuals. Growth in total length can be expressed by a Von Bertalanffy growth curve as $L_t=542[1-{\exp}\{-0.493 (t+0.769)\}]$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.835-842
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• 2013

Flathead flounder Hippoglossoides dubius is a commercially important fish in the coastal waters of Gangwon Province, which is its spawning ground and breeding habitat. A total of 1,669 gonads were sampled monthly from February 2011 to May 2013 to investigate ecological characteristics, such as variations in maturation and spawning by gonad index, visual maturity stage, histological observations and oocyte diameter. Males were numerically dominant over females in the fishing grounds year round. The spawning season was from January to April, and the peak was from February to March. Oocyte number as a measure of fecundity was between 27,372 and 915,209 eggs with a length range of 26.0-48.7 cm TL, while the largest oocyte grew to 0.9-1.4mm in egg diameter during its spawning season. The relationship between fecundity and total length was $F=0.0016TL^{5.2539}$. The smallest mature lengths of the females and males were 28.4 and 22.6 cm respectively, and the 50% mature lengths of females and males were 32.9, 26.9 cm respectively.

• Korean Journal of Ichthyology
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• v.23 no.1
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• pp.75-79
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• 2011

This study was conducted to investigate protocol standardization for cryopreservation spermatozoa of the bar-tailed flathead Platycephalus indicus. The suitability of the cryoprotectants, dimethyl sulphoxide (DMSO), glycerol and methanol were tested against three freezing rates and three thawing temperatures. DMSO and glycerol gave significantly higher motile index and survival rates than methanol. Among the freezing rates, freezing at a height of 2 cm above $LN_2$ surface for $10\;min^{-1}$ gave higher motile index and survival rates. In terms of best thawing temperature, $20^{\circ}C$ obtained the highest motility.