• Clean Technology
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• v.24 no.4
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• pp.357-364
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• 2018

Studies on the production of biogas from third generation biomass, such as micro- and macroalgae, have been conducted through experiments of various scales. In this paper, we investigated the feasibility of commercialization of integrated combined heat and power (CHP) production using biogas derived from macroalgae, i.e., seaweed biomass. For this purpose, an integrated CHP plant of industrial scale, consisting of solid oxide fuel cells, gas turbine and organic Rankine cycle, was designed and simulated using a commercial process simulator. The cost of each equipment in the plant was estimated through the calculated heat and mass balances from simulation and then the techno-economic analysis was performed. The designed integrated CHP process produces 68.4 MW of power using $36ton\;h^{-1}$ of biogas from $62.5ton\;h^{-1}$ (dry basis) of brown algae. Based on these results, various scenarios were evaluated economically and the levelized electricity cost (LEC) was calculated. When the lifetime of SOFC is 5 years and its stack price is $$225kW^{-1}$, the LEC was 12.26 ¢ $kWh^{-1}$, which is comparable to the conventional fixed power generation.

• Korean Chemical Engineering Research
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• v.57 no.4
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• pp.455-460
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• 2019

Hydrotreating catalysis refers to a various hydrogenation which saturate an unsaturated hydrocarbon, together with removing heteroatoms such as sulfur, nitrogen, oxygen, and trace metals from different petroleum streams in a refinery. Most refineries include at least three hydrotreating units for upgrading naphtha, middle distillates, gas oils, intermediate process streams, and/or residue. Among them, hydrotreating catalysis for residue are the core of the process, because of its complexity. This article reviews recent progress in tackling the issues found in the upgrading residues by hydrotreating, focusing on the chemistry of hydrodemetallization (HDM) and hydrodesulfurization (HDS). We also discuss the composition and functions of hydrotreating catalysts, and we highlight areas for further improvement.

• Journal of Convergence for Information Technology
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• v.12 no.1
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• pp.135-143
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• 2022

In this study, the antioxidant and anti-inflammatory properties of Colpomenia sinuosa extracts were identified. Antioxidant experiments included DPPH, ABTS, nitrite scavenging experiments, and FRAP, polyphenol concentration measurements, flavonoid concentration measurements. DPPH assay results showed an antioxidant function of 2.821 mg ascorbic acid/g extract. ABTS assay results showed an antioxidant function of 3.923 mg ascorbic acid/g extract. nitrite assay results showed an antioxidant function of 17.89 mg ascorbic acid/g extract. In FRAP, 1 mg of the Colpomenia sinuosa extract showed a reduction of 2.062±0.177 ㎍ of ascorbic acid. For polyphenols, 62.85±3.18 mg/g was shown. Flavonoids showed 10.01±0.24 mg/g. In the meantime, cell experiments showed cytotoxicity and anti-inflammatory functions. In cytotoxicity experiments, Colpomenia sinuosa extracts showed cytotoxicity of less than 20% and an inflammatory inhibition of 30.93±2.93% at a concentration of 100 ㎍/mL. These results indicate that Colpomenia sinuosa extract is available as functional cosmetic material.

• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.693-700
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• 1996

The purpose of this study was to determine whether workers at a factory next to a lead recycling factory in Pusan, were affected by lead contamination. The mean air lead concentration of lead recycling factory was $0.21mg/m^3(TWA=0.05mg/m^3)$. Thirty-nine male workers of Factory A, Cr. plating factory next to the lead recycling factory were exposed group and a comparison group, 62 male workers of Factory B were selected from another Cr. plating factory about 8.5km away from lead recycling factory. Air lead concentration of each workplace was checked for 4 times from August f to August 20 in 1995 by low volume air sampler. Each subject was interviewed about age, life-style, smoking, work history, and residence etc, and venous blood was drawn for lead measurement by graphite furnace atomic absorption spectrometry. We have observed that air lead concentration and blood lead concentration of Factory A was higher than Factory $B(2.6{\pm}1.6\;Vs.\;1.2{\pm}0.2{\mu}g/m^3,\;14.9{\pm}1.6\;Vs.\;12.2{\pm}1.6{\mu}g/dl)$. We believe that other environmental lead sources such as transportation and residence did not affect air lead and blood lead concentration differences of both factory. We concluded that high air lead and blood lead concentration of Factory A were caused by lead contamination generated by the neighboring lead recycling factory.

• Journal of the Korea Organic Resources Recycling Association
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• v.6 no.2
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• pp.7-30
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• 1998

Generation and recycling potential of organic waste in Korea were estimated. Status of organic waste composting and compost utilization also were surveyed to promote the recycling of organic waste. From 1994 to 1997, generation of garbage decreased gradually while recycling rate increased due to positive governmental strategy. During the same period, livestock waste increased 11.2%. Municipal wastewater sludge was generated 3,500 ton/day which was 0.03% of wastewater treated in 1996. The energy Potential of industrial organic waste was estimated to 288 million TOE which was 1.75% of the nationwide first energy consumption in 1996. Recycling of industrial sludge was low to 31%, while recycling of animal waste, plant scraps, and wasted paper were relatively high over 50%. Industrial sludge should be recycled more as it was the most part of industrial organic waste. Conventional composting materials were mainly livestock waste, food processing waste, fishery waste, sawdust, and nightsoil. Garbage and sludge have been composted recently. 420,000 tons of compost in 1996 were produced by 288 makers, the most of which were utilized in agriculture. It was suggested that separated collection, compost standard, and quality management should be provided to promote the composting of organic waste.

• Journal of Life Science
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• v.28 no.12
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• pp.1501-1506
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• 2018

Edible insects have recently been increasingly promoted as a source of protein. As the number of farms rearing these insect increases, it is important to develop safe and nutritious feed sources to improve their commercial quality. The aim of the current study was to determine the effect of food by-products as feed supplements for the Korean rhinoceros beetle, Allomyrina dichotoma, which has been registered as a general food ingredient in Korea. We compared the effects of waste citrus peel, soybean curd cake, soybean oil meal, and brewers' dried grain on the growth of third instar larvae of A. dichotoma. Groups of larvae were fed with fermented sawdust and nine different combinations of the above by-products and the effects on their growth were measured until pupation. The highest survival rate was with feed supplemented with 10% brewers' dried grain (66.7%, p<0.05), and these larvae were also 26% heavier (p<0.05) than the control group that received no supplementation. In the 10% brewers' dried grain group, the larval period of third instar was shortened by almost 28 days (p<0.01) compared to the control group. Of all the groups, only that which was fed the brewers' dried grain supplement showed more than a 90% pupation rate (p<0.05). Therefore, brewers' dried grain may be useful as a source of feed for A. dichotoma.

• Food Science and Industry
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• v.51 no.4
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• pp.278-301
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• 2018

Although more than 80% of living organisms are found in marine ecosystems, only less than 10% of marine resources have been utilized for human food consumptions and other usages. It is well known that marine resources (fish, shellfish and algae) have exceptional nutritional properties; however, their functional characteristic has not been completely discovered. It is believed that metabolites (organic compounds, proteins, peptides, lipids, minerals, etc.) play an important role to show its biological properties. Marine proteins and peptides are considered to be future drugs due to their excellent biological activities with a fewer adverse side effect. Marine peptides show several biological activities, including antimicrobial, antioxidant, anti-inflammatory, anti-cancer, anti-viral, anti-tumor, anti-diabetic, anti-hypertensive, anti-coagulant, immunomodulatory, appetite suppressing and neuroprotective effects. Therefore, the pharmaceutical, nutraceutical, and cosmeceutical companies have been paid attention to the marine peptides to commercialize into products. This current review mainly focused on the above mentioned biological activities of marine peptides and protein hydrolysates as a functional food and pharmaceutical applications. To commercialize these materials in industrial level required large quantity in high-purity level, and it is complicated to produce huge quantity from the marine resources due to insufficient raw materials, unavailability of raw materials through a year, hinder the growth with geographical variations, and availability of compounds in extreme small quantities. The best solution for these issues is to introduce new modern technologies such as artificial intelligence robots, drones, submersibles and automated raw material harvesting vessels in farming industries instead of man power, which will lead to 4th industrial revolution.

• Clean Technology
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• v.14 no.2
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• pp.71-86
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• 2008

In this review we discussed the effective ways to catalytically derive value-added chemicals from propane which has been utilized only as an energy source so far. Among various propane-derived products, the most valuable chemicals such as propylene and acrylonitrile were mainly focused herein. Propylene could be manufactured through oxidative dehydrogenation of propane using $O_2,\;CO_2$, etc. as an oxidant for the purpose of overcoming thermodynamic limitations of propane dehydrogenation. On the other hand, propane ammoxidation would be an alternative to propylene ammoxidation for producing acrylonitrile since propane is much cheaper than propylene as a starting material. Although effective $MoVTeNbO_x$ catalysts have been developed fur propane ammoxidation in recent years, more detailed studies should be thoroughly performed. In carrying out both oxidative dehydrogenation and ammoxidation of propane fur a long period, the most critical issue is definitely considered to find out the most active and selective catalysts, which makes it possible to commercialize both reactions into economically viable processes.

• Applied Biological Chemistry
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• v.51 no.1
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• pp.84-87
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• 2008

In this research, we screened for glucosyltransferase (GTase) inhibitors that effectively prevent the dental caries from 420 kinds of boiled water extracts of herbs and wild plants and searched for GTase inhibitory activities. Among them, 13 kinds of hot water extracts had high GTase inhibitory activities and especially, we focused on Foeniculum vulgare which showed the highest inhibitory activity on GTase. The boiled water extract of F. vulgare was stable at high temperature and showed as a mixed type of competitive and uncompetitive inhibition kinetic behavior. It did not have antibacterial effect on Streptococcus mutans and had inhibitory activity on GTase. Specially, in the clinical trial, the group treated by boiled water extract of F. vulgare showed more decrease of plague index at 4.8 point than untreated group. These results suggested that boiled water extract of F. vulgare can effectively suppress the plague formation as it inhibits the GTase activity.

• Journal of Nutrition and Health
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• v.54 no.1
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• pp.116-128
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• 2021

Purpose: The extraction conditions for bioactive components from peanut shells, which is a byproduct of peanut processing, were optimized to enhance the total phenolic content (TPC, Y1), total flavonoid content (TFC, Y2), and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (RSA, Y3). In addition, this study evaluated the anti-obesity effect of peanut shell extract. Methods: Optimization of ultrasonic-assisted extraction (UAE) was performed using a response surface methodology. The independent variables applied for extraction were time (X1: 5.0-55.0), temperature (X2: 26.0-94.0), and ethanol concentration (X3: 0.0%-99.5%). Quadratic regression models were derived based on the results of 17 experimental sets, and an analysis of the variance was performed to verify its accuracy and precision of the regression equations. Results: When evaluating the effects of independent variables on responses using statistically-based optimization, the independent variable with the most significant effect on the TPC, TFC, and RSA was the ethanol concentration (p = 0.0008). The optimal extraction conditions to satisfy all three responses were 35.8 minutes, 82.7℃, and 96.0% ethanol. Under these conditions, the inhibitory activities of α-glucosidase and pancreatic lipase by the extract were 86.4% and 78.5%, respectively. Conclusion: In this study, UAE showed superior extraction efficiency compared to conventional hot-water extraction in the extraction of polyphenols and bioactive materials. In addition, α-glucosidase and pancreatic lipase inhibitory effects were identified, suggesting that peanut shells can be used as effective antioxidants and anti-obesity agents in functional foods and medicines.