• Korean Journal of Ichthyology
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• v.13 no.2
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• pp.129-135
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• 2001

Matured adults of Siniperca scherzeri were collected from Soyangdam and Hongchun river, Gangwon-do, Korea. The fertilized eggs were hatched and reared in the laboratory of the Korea Ocean Research and Development Institute. Osteological development of the larvae and juveniles of Siniperca scherzeri were investigated. Three days after hatching, the larva (6.12 mm in total length: TL) had partly ossified parasphenoid, clavicle, hyomandibular, preopercle, opercle and jaw bones with 7 to 8 canine teeth. The ascending process of premaxillary and ca 19 and 23 teeth on the premaxillary and dentary, respectively, were ossified at 10 days after hatching. Also at 10 days, the vertebral columns of the larvae (6.85 mm in TL) were posterioly ossified to the 5~7th vertebra, and ossification was completed in the juvenile (10.99 mm in TL) on the 22 nd day. Thus ossification began 3 days after hatching, and was completed 22 days after hatching.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.902-908
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• 2010

In 2008, we monitored residual pesticides of 15 agricultural products such as rice, corn, pea, chestnut, mandarin, lemon, onion, pineapple, lettuce, chard, sweet potato stalk, burdock, squash, sweet pepper and mushroom. Agricultural commodities were collected from markets in 22 provinces (Seoul, Busan, Incheon, Daegu, Ulsan, Daejeon, Gwangju, Wonju, Pohang, Gumi, Changwon, Gimhae, Suwon, Seongnam, Bucheon, Goyang, Yongin, Cheongju, Cheonan, Jeonju, Yeosu, and Jeju). Total 48 pesticides were analysed by multi-residue method using GC/MS/MS. We analysed 1,064 samples and 34 samples (3.20%) were detected. Sweet potatostalk, burdock, chestnuts, peas, corn, chard, squash, mushroom and onions were found to be free from pesticide residues. 6 other agricultural products did not exceed MRLs (Maximum Residue Limits) by the Korean Food Code. Chloropyrifos and fenobucarb were particularly prevalent and also they were detected over 10 times in this monitoring. Nonetheless, the exposed quantity of the 7 residual pesticides is to be considered relatively safe, compared with the acceptable daily intake (ADI) of residual pesticides.

• Analytical Science and Technology
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• v.25 no.6
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• pp.364-369
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• 2012

Isotianil is a novel fungicide which induces systemic acquired resistance in plants. It has excellent preventive effects as low dosages against rice blast which is one of the most serious diseases in rice. The Maximum Residue Limit (MRL) of Isotianil in republic of korea was set to 0.1 mg/kg in rice, so it is necessary to determine levels of Isotianil residues in agricultural commodities for controlling food safety. Therefore, The purpose of this study was to develop analytical method for the determination of isotiical residues in agricultural commodities using GC-NPD/MSD. Isotianil was extracted with acetonitrile from apple, chinese cabbage, hulled rice, mandarin, pepper, and soybean. The extract was diluted with saline water, and then dichloromethane partition was followed to recover this fungcide from the aqueous phase. A solid phase extraction with Florisil cartridge was additionally employed for final clean up. Isotianil was analyzed and quantitated by GC-NPD and confirmed by GC-MSD. Average recovery of Isotianil ranged from 70.0 to 103.9% in six representative agricultural commodities with relative standard deviations less than 10%, and limit of quantification (LOQ) was 0.05 mg/kg.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.859-867
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• 2016

This study was conducted at rearing room to investigate the feeding behavior of fruits in the firefly (Pylocoelia rufa) larvae and the ovipositional characteristics of the adults. As a result, the pear, apple, melon, persimmon, mandarin, grape and peach were shown the feeding behavior of larvae the average 6.40, 3.25, 2.50, 2.20, 2.00, 1.40 and 1.25, respectively. However, the larvae were not shown at all feeding behavior to banana. The hours feeding behavior of firefly larvae was primarily from 8:00 pm until 2:00 am. In addition, the time at which the voracious feeding behavior was until 8:00 pm to 12:00 pm. The 6:00 pm began whisking all the larvae are hiding in the shelter. In the case of the firefly larvae fed only the edible snail, the adults were oviposition an average $49{\pm}6$ eggs. At that time larva stage, adults of the firefly eating the pears, apples, melon and eat edible snail at the same time there were oviposition the $53{\pm}7$ on average. In the case of fruits, the pears, apples, and melons has been considered worthy to take the firefly larva fed with the current land snails.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.326-335
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• 2015

Citrus is an economically important fruit tree with the largest amount of fruit production in the world. It provides important nutrition such as vitamin C and other health-promoting compounds including its unique flavonoids for human health. However, it is classified into the most difficult crops to develop new cultivars through conventional breeding approaches due to its long juvenility and some unique reproductive biological features such as gamete sterility, nucellar embryony, and high level of heterozygosity. Due to global warming and changes in consumer trends, establishing a systematic and efficient breeding programs is highly required for sustainable production of high quality fruits and diversification of cultivars. Recently, reference genome sequences of sweet orange and clementine mandarin have been released. Based on the reference whole-genome sequences, comparative genomics, reference-guided resequencing, and genotyping-by-sequencing for various citrus cultivars and crosses could be performed for the advance of functional genomics and development of traits-related molecular markers. In addition, a full understanding of gene function and gene co-expression networks can be provided through combined analysis of various transcriptome data. Analytic information on whole-genome and transcriptome will provide massive data on polymorphic molecular markers such as SNP, INDEL, and SSR, suggesting that it is possible to construct integrated maps and high-density genetic maps as well as physical maps. In the near future, integrated maps will be useful for map-based precise cloning of genes that are specific to citrus with major agronomic traits to facilitate rapid and efficient marker-assisted selection.

• Journal of Nutrition and Health
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• v.48 no.1
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• pp.94-104
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• 2015

Purpose: The purpose of this study was to estimate dietary folate intake and food sources of children and adolescents using a nutrient database revised based on measured folate in selected foods. Methods: Folate content in 51 foods known as folate sources was measured by microbiological assay after trienzyme extraction. Folate intake was estimated from a part of the data of 'Dietary Intake Survey of Infants, Children and Adolescents in 2007~2008' conducted by the Korea Food and Drug Administration (KFDA) and the Korea Health Industry Development Institute (KHIDI). The study subjects were 567 children aged 1~19 years living in the Chungcheong area who completed two 24-hour recalls. Results: Folate values were revised by replacing the values in the current database with the analyzed values except when the value in the current database was between the analytical values or was not different from the mean analytical value by more than 10%. Among the revised values of 40 food items, folate values of 36 foods were lower than the current values. Mean folate intakes estimated with the revised database were approximately 70~80% lower than those estimated with the current database. Mean folate intakes of males aged 12~14 and females aged 12~19 were lower than the 2010 Recommended Nutrient Intakes (RNIs). Chicken's eggs, Kimchi, rice, mandarin, and laver were found to be main food sources of folate. Conclusion: In this study, mean dietary folate intakes were lower than those estimated with the current database. Further analyses for folate content especially in cooked foods commonly consumed in Korea are needed using a reliable assay in order to accurately assess folate intake of the Korean population. In addition, nutrition education should be provided for adolescent females in order to increase consumption of folate-rich foods.

• Korean Journal of Food Science and Technology
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• v.46 no.1
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• pp.7-12
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• 2014

A sensitive and simple analytical method to identify flutianil residues in agricultural commodities was developed and validated using gas chromatography-electron capture detection (GC-ECD) and mass spectrometry (GC-MS). The flutianil residues were extracted with acetonitrile, partitioned with dichloromethane, and then purified using a silica solid-phase extraction (SPE) cartridge. The method was validated using pepper, sweet pepper, mandarin, hulled rice, soybean, and potato spiked with 0.02 or 0.2 mg/kg flutianil. The average recovery of flutianil was 76.5-108.0% with a relative standard deviation of less than 10%. The limit of detection and limit of quantification were 0.004 and 0.02 mg/kg, respectively. The result of recoveries and relative standard deviation were in line with Codex Alimentarius Commission Guidelines (CAC/GL 40). These results show that the method developed in this study is appropriate for flutianil identification and can be used to maintain the safety of agricultural products containing flutianil residues.

• Analytical Science and Technology
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• v.26 no.2
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• pp.142-153
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• 2013

A new, rapid, and simple analytical method was developed and validated using high performance liquid chromatograph-photodiode array detector (HPLC-PAD) for the determination of lepimectin residues in agricultural commodities. The lepimectin residues in samples were extracted with methanol, partitioned with dichloromethane, and then purified with glass column filled with subsequently to aminopropyl ($NH_2$) solid phase extraction (SPE) cartridge. The purified samples were detected using HPLC-PAD. Correlation coefficient ($R^2$) of both lepimectin $A_3$ and $A_4$ solutions were 0.9999. The method was validated using cucumber spiked with lepimectin at 0.02 and 0.2 mg/kg and pepper, mandarin, hulled rice, potato, soybean at 0.02 and 0.5 mg/kg. Average recoveries were 76.0~114.8% with relative standard deviation less than 10%, and limit of detection (LOD) and limit of quantification (LOQ) were 0.005 and 0.01 mg/kg, respectively. The result of recoveries and overall coefficient of variation of a laboratory results in Gwangju regional KFDA and Daejeon regional KFDA was followed with Codex guideline (CAC/GL 40). Therefore, developed method in this study is accurate, rapid, and appropriate for lepimectin determination and will be used to keep safety of lepimectin residues in agricultural products.

• Applied Biological Chemistry
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• v.36 no.4
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• pp.265-270
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• 1993

In order to retain the freshness of fruits and vegetables and to reduce the rate of disease damage, grafruit seed extract (GPSE), natural microorganism control agent, was applied during the preservation process of fresh fruits and vegetables. GFSE showed an effective inhibitory action against plant putrefactive bacteria and fungi which were involved in the decay of fruits and vegetables. Minimal inhibitory concentrations for GFSE against the microbes were in the range of 50 to 2,000 ppm. Direct observation of microbial cells and spores using electron microscopy showed their function was destroyed by the treatment of the dilute solutions of GFSE. Fresh Welsh onions, onions and red peppers treated with GFSE and stored in polyethylene film (0.1 mm) retained better quality in color and texture than the non-treated control. GFSE was efficient in controlling the germination of potatoes. It was observed that GFSE would reduce disease damages and have bactericidal and fungicidal properties during the storage of such fruits and vegetables as zucchinis, cucumbers, tomatoes and mandarin oranges.

• The Korean Journal of Pesticide Science
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• v.17 no.2
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• pp.84-93
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• 2013

Validated analytical methods for isopyrazam are meager or lacking. In the present study, a single residual analytical method was developed for isopyrazam in selected commodities. Isopyrazam was analyzed in brown rice, soybean, green pepper, mandarin, cucumber, and Korean melon. We tried different solvents and methods through extraction, partition and purification steps to obtain best analytical results. For isopyrazam samples were extracted with acetonitrile, concentrated and partitioned with n-hexane, clean-up using florisil with n-hexane/ethylacetate (70/30) and analyzed with HPLC/UVD. The limit of quantitation (LOQ) for isopyrazam was 1.0 ng (S/N > 10) and method LOQ (MLOQ) was 0.04 mg $kg^{-1}$. Recovery ranged through 81.0~105.3% (syn-isomer) and 80.8~105.6% (anti-isomer) at fortification level of 0.04 (MLOQ), 0.4 (10 ${\times}$ MLOQ), and 2.0 (50 ${\times}$ MLOQ). The coefficient of variation (CV) for isopyrazam was less than 10% regardless of sample types. These results were further confirmed with LC/MS, respectively. The proposed method is highly reproducible and sensitive and is suitable for routine analysis.