• Journal of Life Science
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• v.32 no.8
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• pp.601-610
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• 2022

P. tenebrifer (PT) belongs to the Diptera order and Stratiomyidae family. Recently, insect industry have been focused as food, animal feed and environmental advantages. γ-aminobutyric acid (GABA) and melatonin have been associated with regulating sleep and depression. GABA is the primary inhibitory neurotransmitter and is synthesized via biotransformation of monosodium glutamate (MSG) to GABA by lactic acid bacteria. In this study, we first used a GABA-enhanced PT extract, wherein GABA was enhanced by feeding MSG to PT. The underlying mechanisms preventing stress and insomnia were investigated in a corticosterone (CORT)-induced endoplasmic reticulum (ER) stress and chronic restraint stress (CRS)-exposed mouse model, as well as in pentobarbital (45 mg/kg)-induced sleep behaviors in mice. In the present study, the GABA peak was detected in high-performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD) analysis and showed in Ptecticus tenebrifer water extract (PTW) but not in non-PTW extract. The results showed that PTW and Ptecticus tenebrifer with 70% ethanol extract (PTE) exerted neuroprotective effects by protecting against CORT-induced downregulation of phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2) and cAMP-response element binding protein (CREB) expression. In addition, PTW (300 mg/kg) significantly reduced CORT levels in CRS-exposed mice. Furthermore, PTW (100 and 300 mg/kg) significantly reduced sleep latency and increased total sleep duration in pentobarbital (45 mg/kg)-induced sleeping behaviors, which was related to serum melatonin levels. In conclusion, our results suggest that PTW exerts anti-stress and sleep-enhancing effects by regulating serum CORT and melatonin levels.

• Proceedings of the Korean Society of Crop Science Conference
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• 2023.04a
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• pp.7-7
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• 2023

Currently, the main technologies of various fourth industries are big data, the Internet of Things, artificial intelligence, blockchain, mixed reality (MR), and drones. In particular, "digital twin," which has recently become a global technological trend, is a concept of a virtual model that is expressed equally in physical objects and computers. By creating and simulating a Digital twin of software-virtualized assets instead of real physical assets, accurate information about the characteristics of real farming (current state, agricultural productivity, agricultural work scenarios, etc.) can be obtained. This study aims to streamline agricultural work through automatic water management, remote growth forecasting, drone control, and pest forecasting through the operation of an integrated control system by constructing digital twin data on the main production area of the nojinot industry and designing and building a smart farm complex. In addition, it aims to distribute digital environmental control agriculture in Korea that can reduce labor and improve crop productivity by minimizing environmental load through the use of appropriate amounts of fertilizers and pesticides through big data analysis. These open-field agricultural technologies can reduce labor through digital farming and cultivation management, optimize water use and prevent soil pollution in preparation for climate change, and quantitative growth management of open-field crops by securing digital data for the national cultivation environment. It is also a way to directly implement carbon-neutral RED++ activities by improving agricultural productivity. The analysis and prediction of growth status through the acquisition of the acquired high-precision and high-definition image-based crop growth data are very effective in digital farming work management. The Southern Crop Department of the National Institute of Food Science conducted research and development on various types of open-field agricultural smart farms such as underground point and underground drainage. In particular, from this year, commercialization is underway in earnest through the establishment of smart farm facilities and technology distribution for agricultural technology complexes across the country. In this study, we would like to describe the case of establishing the agricultural field that combines digital twin technology and open-field agricultural smart farm technology and future utilization plans.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.455-462
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• 2000

The objective of this study was to examine the physicochemical characteristics of coagulation reaction between loess and red tide organisms (RTO) and its feasibility, in developing a technology for the removal of RTO bloom in coastal sea. The physicochemical characteristics of loess were examined for a particle size distribution, surface characteristics by scanning electron microscope, zeta potential, and alkalinity and pH variations in sea water. Two kinds of RTO that were used in this study, Cylindrothen closterium and Skeietonema costatum, were sampled in Masan bay and were cultured in laboratory. Coagulation experiments were conducted using various concentrations of loess, RTO, and a jar tester. The supernatant and RTO culture solution were analyzed for pH, alkalinity, RTO cell number. A negative zeta potential of loess increased with increasing pH at $10^(-3)M$ NaCl solution and had -71.3 mV at pH 9.36. Loess had a positive zeta potential of +1,8 mV at pH 1.98, which resulted in a characteristic of material having an amphoteric surface charge. In NaCl and $CaCl_2$, solutions, loess had a decreasing negative zeta potential with increasing $Na^+\;and\;Ca^(+2)$ ion concentration and then didn't result in a charge reversal due to not occurring specific adsorption for $Na^+$ ion while resulted in a charge reversal due to occurring specific adsorption for $Ca^(+2)$ ion. In sea water, loess and RTO showed the similar zeta potential values of -112,1 and -9.2 mV, respectively and sea sand powder showed the highest zeta potential value of -25.7 mV in the clays. EDLs (electrical double-layers) of loess and RTO were extremely compressed due to high concentration of salts included in sea water, As a result, there didn't almost exist EDL repulsive force between loess and RTO approaching each other and then LVDW (London-yan der Waals) attractive force was always larger than EDL repulsive force to easily form a floe. Removal rates of RTO exponentially increased with increasing a loess concentration. The removal rates steeply increased until $800 mg/l$ of loess, and reached $100{\%}$ at 6,400 mg/l of loess. Removal rates of RTO exponentially increased with increasing a G-value. This indicated that mixing (i.e., collision among particles) was very important for a coagulation reaction. Loess showed the highest RTO removal rates in the clays.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.4
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• pp.549-556
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• 2015

This study extracted radish bud (Raphanus sativus L.) and investigated its nitrite scavenging activity, superoxide dismutases (SOD)-like activity, tyrosinase inhibition activity, xanthine oxidase inhibition activity, and angiotensin-converting-enzyme (ACE) inhibition activity according to extraction solvent and sprouting period. For nitrite scavenging activity, each extract recorded its highest level of 81.44~89.71% at pH 1.2. Radish bud extracts on sprouting days 4 and 8 showed greater scavenging activities than those on sprouting day 12 at pH 1.2 and pH 4.0. There were differences in scavenging activity according to extraction solvent based on water extract exhibiting improved scavenging activity. Ethanol extract recorded scavenging activity of 16.12% at pH 6.0, which was similar to those of ethanol and methanol radish bud extracts on sprouting day 12. SOD-like activity of radish bud extracts was in the range of 4.57~27.05%. For comparison purposes, SOD-like activity of L-ascorbic acid was 52.15%, which was higher than that of radish bud extracts. Acetone and methanol extracts showed high SOD-like activities on sprouting day 8. SOD-like activity of radish bud extracts on sprouting day 12 significantly decreased to 4.57~15.59%. Radish bud extracts recorded good tyrosinase inhibitory activities on sprouting 8 and 12, whereas methanol extracts recorded the greatest tyrosinase inhibitory activity at 62.65~84.89%. Radish bud extracts recorded xanthine oxidase inhibition activity of 21.26~29.52% on sprouting day 4, and acetone extracts showed the highest level of xanthine oxidase inhibition activity. Xanthine oxidase inhibitory activity tended to decrease with sprouting period compared early on. ACE inhibitory activity was in the range of 12.48~51.78% according to sprouting period and extraction solvent. Ethanol extracts on sprouting day 8 showed the highest ACE inhibitory activity of 51.78%. These results will hopefully contribute to research into the identification of materials and development of products for natural functional foods.

• Food Science and Preservation
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• v.16 no.6
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• pp.797-803
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• 2009

The effects of drying methods on the browning and moisture sorption characteristics of Rubus coreanus were studied. Fruits were steamed for 5 min at $100^{\circ}C$, dried by sun drying, infrared drying, or freeze drying, and powdered to a size of 20 mesh. Color values were measured and equilibrium moisture contents (EMC) were determined at $20^{\circ}C$, over a range of water activity ($a_w$) from 0.11 to 0.90. The browning indices $L^*$ and $a^*$ values were higher and lower, respectively, in freeze-dried Rubus coreanus compared with other samples. The $b^*$ value was greatest in freeze-dried Rubus coreanus. EMC tended to increase with increasing $a_w$ values, and a particularly sharp increment was observed above 0.75 $a_w$. The EMC of freeze-dried Rubus coreanus was significantly higher compared with the EMC of sun-dried and infrared-dried fruit at constant aw. The moisture sorption isotherms showed a typical sigmoid shape, and the Halsey, Kuhn, and Oswin models were the best fits for the sun-dried, infrared-dried, and freeze-dried powder isotherms, respectively. With respect to monolayer moisture content, the Guggenheim-Anderson-Boer (GAB) equation showed that the various drying methods yielded very different results, with monolayer moisture contents of 0.005 g $H_2O/g$ dry solid in infrared-dried and 0.019 g $H_2O/g$ dry solid in sun- and freeze-dried powders, respectively. These results indicate that the drying method affects the browning and moisture sorption characteristics of Rubus coreanus.

• Journal of Life Science
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• v.23 no.9
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• pp.1147-1154
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• 2013

This study was conducted to evaluate the antioxidation activity of Jeju crossbred horse (Jeju native horse ${\times}$ thoroughbred) leg bone extracts (HLBE) and its enzyme hydrolysates by determination of 1,1-diphenyl-2picryl-hydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzo thiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity, ferric reducing/antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC). HLBE was extracted with hot water for 24 hr and lyophilized. The lyophilized HLBE was hydrolyzed using multifect PR6L (MP), pepsin (PS), and a pepsin and pancreatin mixture (PSPC) for 4 hr at 60, 50, and $50^{\circ}C$, respectively. The hydrolysates were separated by a molecular weight of 3 kDa more or less. When the yield of HLBE was 100%, the yield of hydrolysates less than 3 kDa of MP, PS, and PSPC was 10.86, 3.26, and 8.00%, respectively. Enzyme hydrolysates with low molecular weight less than 3 kDa in MP and PSPC showed significantly higher DPPH, ABTS radical scavenging activity, and ORAC compared to HLBE and its hydrolysates with more than 3 kDa. However, the FRAP of the hydrolysates less than 3 kDa in PS was significantly higher than in MP. These results suggest that low molecular weight enzyme hydrolysates less than 3 kDa have more powerful antioxidation activity, especially when they are hydrolyzed by MP and PSPC rather than PS. Therefore, low molecular weight enzyme hydrolysates of HLBE hydrolyzed with MP and PSPC have significant potential as antioxidants in the food industry. Further in vivo studies are required to support the antioxidation activities of the hydrolysates in vitro.

• Korean Journal of Ecology and Environment
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• v.44 no.3
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• pp.264-271
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• 2011

At the Jangheung multipurpose dam, which is on the Tamjin River, a trapping and trucking operation was established to maintain continuous upstream migration of fish,. To facilitate fish gathering, installation of an effective fishing trap was required. In this study, we evaluated the fish trap, established at the Jangheung dam, using PIT (Passive Integrated Transponder) telemetry. A total of 254 individuals from 15 species were monitored. Among these tagged species, 36 individuals from 6 species (Carassius auratus, C. cuvieri, Zacco temminckii, Z. platypus, Pungtungia herzi, and Pseudobagrus koreanus) were detected; a 14.2% detection rate. C. auratus recorded the highest detection rate of 44.2% while P. herzi was 14.3%. Z. temminckii and Z. platypus showed relatively low detection, 5% and 7.7% respectively. Some of individuals from C. auratus and Z. platypus did not pass through the antenna at the first attempt but were continuously detected on multiple days. There were no statistical differences in body size (total length, standard length and body weight) of individuals that did or did not swim into the trap (Mann-Whitney U test, p>0.05). Fish mainly swam into the trap during outflow of water from the dam (Mann-Whitney U test, p<0.001) and showed a higher detection frequency in daytime than nighttime (Mann-Whitney U test, p<0.001). Thus, for fish movement into the trap, external factors such as outflow from dam and time of day have important roles. Based on detection rate, not all fishes showed upstream migration but represented selective migration. Consequently, the establishment of flexible outflow strategies that take into consideration ecological characteristics of fishes should required for improving the efficiency of fishway.

• Journal of Life Science
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• v.26 no.11
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• pp.1237-1244
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• 2016

A comprehensive analysis of the genetic diversity and relationship of the cold-water fishery walleye pollock (Theragra chalcogramma), the most abundant economically important fishery resource in the East sea of Korea, has not been carried out, despite its importance in Korea. The present study assessed the genetic diversity and relationship between five walleye pollock populations (Korean population, Russian population, USA population, and Japanese populations) of T. chalcogramma using eight microsatellite DNA (msDNA) markers to provide the scientific data for the preservation and management of the Pollock fishery resource. The results of the analysis of 186 individuals of the Pollock revealed a range of 7.13-10.63 numbers of alleles (mean number of alleles=9.05). The means of observed heterozygosity ($H_O$), expected heterozygosity ($H_E$) were 0.732 and 0.698, respectively. The results of genetic distance, Pairwise $F_{ST}$, UPGMA (UPGMA: un-weighted pair-group method with an arithmetical average) (the phylogenetic tree), PCA (PCA: Principal Coordinate analysis) analysis pointed to significant differences between the Korean population, Russian population, USA population, and Japanese populations, although small (p<0.05). These results shed light on the genetic diversity and relationships of T. chalcogramma and can be utilized for research on the evaluation and conservation of Korean T. chalcogramma as genetic resources.

• Journal of Food Hygiene and Safety
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• v.26 no.3
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• pp.273-282
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• 2011

This study established hazards which may cause risk to human at farm during cultivation stage of paprika. Samples of plants (paprika, leaf, stem), cultivation environments (water, soil), personal hygiene (hand, glove, clothes), work utensils (carpet, basket, box) and airborne bacteria were collected from three paprika farms (A, B, C) located in Western Gyeongnam, Korea. The collected samples were assessed for biological (sanitary indications and major foodborne pathogens), chemical (heavy metals, pesticide residues) and physical hazards. In biological hazards, total bacteria and coliform were detected at the levels of 1.9~6.6 and 0.0~4.610g CFU/g, leaf, mL, hand or 100 $cm^2$, while Escherichia coli was not detected in all samples. In major pathogens, only Bacillus cereus were detected at levels of ${\leq}$ 1.5 log CFU/g, mL, hand or 100 $cm^2$, while Staphylococuus aureus, Listeria monocytogenes, E. coli O157 and Salmonella spp. were not detected in all samples. Heavy metal and pesticide residue as chemical hazards were detected at levels below the regulation limit, physical hazard factors, such as insects, pieces of metal and glasses, were also found in paprika farms. Proper management is needed to prevent biological hazards due to cross-contamination while physical and chemical hazards were appropriate GAP criteria.

• Korean journal of food and cookery science
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• v.16 no.4
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• pp.342-351
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• 2000

This study aimed for exploring the best recipe of Sangjabyung to increase its utility value and to develop traditional Korean rice cake industry for next generation. The best recipe was determined after several tests such as sensory evaluation and mechanical measurements for texture, moisture content, and colorimetry. The samples prepared with 5% of acorn starch with honey showed the best scores in sensory evaluation for color and flavor, 5% of acorn powder with sugar for grain, 15% of acorn powder with sugar for moistness and chewiness, 15% of starch with honey for sweetness, and non-glutinous rice flour mixed with 10% of acorn powder and sugar for overall quality. Every item except for flavor was significantly different from that of control (P<0.05). The highest score for springiness was obtained from the samples prepared with 10% of acorn starch with sugar, cohesiveness with 5% of acorn starch with sugar, chewiness with 15% of acorn starch with honey, gumminess with 15% of acorn starch with honey, adhesiveness with 5% of acorn starch with honey, and hardness with 15% of acorn starch with honey. All items were significantly different from that of control (P<0.05). The overall quality of sensory evaluation was correlated with moistness(P<0.05), springiness, cohesiveness(P<0.01), and adhesiveness(P<0.01) in mechanical test. Moisture contents of rice flour, acorn starch, and acorn powder were 32.93%, 8.52%, and 13.26%, respectively. The desirable moisture content in Sangiabyung was 44.11% in the case of using rice flour with acorn starch or 44.33% for rice flour with acorn powder. As a result of colorimetry, the best L, a, and b values were obtained from the rice cakes with 5% acorn starch and oligosaccharides, with 15% of acorn powder and sugar, and with 15% of acorn starch with oligosaccharides, respectively. Overall. the most desirable recipe for Sangjabyung was determined as rice flour 315 g, acorn starch or acorn powder 35 g, sugar 60 g, salt 3.5 g, and water 130 ml.