• Food Science and Preservation
• /
• v.22 no.1
• /
• pp.129-133
• /
• 2015

The antioxidant potentials of ten kinds of medicinal plants used as natural dyeing agents were tested. Among the plant extracts and floral waters that were examined in this study, the antioxidant activities of the DPPH and ABTS radical scavengers increased with increasing amounts of the extracts. The hot-water extracts from Aphis chinensis, Caesalpinia sappan L., Rumex crispus L., and Areca catechu effectively inhibited the DPPH and ABTS radicals at concentration below 0.1 mg/mL. The floral water obtained through steam distillation from Areca catechu, Rubia akane Nakai, Coptis chinensis, and Phellodendron amurense showed relatively valid antioxidant activities. In particular, the natural colorants extracted from Rumex crispus L., Areca catechu, and Aphis chinensis effectively suppressed the photogenerated singlet oxygen induced by a photosensitizer in in-vitro assay systems. The concentrations ($IC_{50}$) of the hot-water Aphis chinensis extract required to exert a 50% reduction effect on DPPH, ABTS, and singlet oxygen were found to be 8.5, 8.0, and $210{\mu}g/mL$, respectively. The study results suggest that extracts derived from naturally occurring colorants as well as floral waters could be used as natural antioxidants in the food and health-care industries.

• Korean Journal of Plant Resources
• /
• v.27 no.1
• /
• pp.29-34
• /
• 2014

The aim of the study was to examine the cosmetic and biological activity of Lagerstroemia indica L. and it is possible that can be used as a cosmetic ingredient for application of cosmetic industries. Lagerstroemia indica L. branch was extracted with 70% acetone in water. In the result of DPPH (1,1-diphenyl-2-picryl-hydrazyl) scavenging radical activity, acetone extract of Lagerstroemia indica L. branch were higher than 73% at the 50 ppm concentration. ABTS radical cation decolorization activity by acetone extract were higher than 78% at the 50 ppm. Both examine of DPPH and ABTS showed high antioxidative activities at the 50 ppm. In the result of nitrite scavenging ability, acetone extract were higher than 63% at the 50 ppm. Collagenase inhibition activity by extract were higher than 85% at the 50 ppm. Extract is showed high collagenase inhibition more than comparison group EGCG at all concentration. These results suggest that Lagerstroemia indica L. has a great potential as a cosmeceutical raw material as well as anti-oxidant and anti-inflammatory and collagenase inhibition activity.

• Korean Journal of Food Science and Technology
• /
• v.44 no.6
• /
• pp.699-703
• /
• 2012

The quality of commercial cider vinegars was compared according to their acidity levels (low, general, double strength and triple strength). The pH, reducing sugar content and brown color intensity decreased, while the total acidity increased with the increasing acidity levels, which may be resulted from difference in formulation and manufacturing procedures. The free sugars were mainly composed of fructose and glucose, which were the highest in low acidity vinegar, followed by double strength, general, and triple strength acidity vinegars. Acetic acids and malic acids were identified as the major organic acids. The citric acid concentration was the highest in triple strength vinegars. The contents of total phenolics and flavonoids were the highest in low acidity vinegars, which indicated their dependence on the apple juice content. DPPH and ABTS radical scavenging abilities were the highest in low acidity vinegars, that showed high amounts of antioxidants.

• Korean Journal of Food Science and Technology
• /
• v.41 no.1
• /
• pp.21-26
• /
• 2009

Polycyclic aromatic hydrocarbon(PAH) contents were evaluated in sesame oils from sesame seeds of different origins and in commercial samples using HPLC with fluorescence detection. The sesame seeds, which had been harvested from India, China, and Korea, were roasted at $250^{\circ}C$ for 25 min, and the commercial sesame oils were purchased from a local market. The recoveries for eight PAHs spiked into the sesame oils ranged from 80.2 to 99.2%. The mean levels of total PAHs in the sesame oils harvested from China, Korea, and India were 3.97, 1.57, and 1.20 ${\mu}g$/kg, respectively. The PAH contents in the commercial sesame oils ranged from 0.79 to 2.15 ${\mu}g$/kg.

• Membrane Journal
• /
• v.26 no.5
• /
• pp.381-390
• /
• 2016

In this study, the natural mordenite (MOR) zeolite seeds were used for the synthesis of high purity mordenite crystals. The effect of seed concentration and crystallization time on the phase purity and surface morphology of MOR crystals has also been reported. The diffraction, elemental and scanning analysis of MOR zeolite particles obtained from 100 g hydrothermal solution batch containing 3 g natural seed, hydrothermally treated at $140^{\circ}C$ for 72 h reveal the high phase-purity of as-synthesized sample having crystals of uniform size ($1-2{\mu}m$). Moreover, high seed concentration leads to the production of mesoporous MOR particles composed of needle shape primary nano crystallites. The gases adsorption performances of as-synthesized MOR particle were carried out at $25^{\circ}C$ and 0-1 bar. Surprisingly, MOR particles show good adsorption potential for $CO_2$ (97.19 mg/g) compared to other gases. Thus it confirms that high purity MOR particles can be synthesized without using any organic template which gives an advantage of separation performance at lower price.

• Analytical Science and Technology
• /
• v.18 no.6
• /
• pp.511-519
• /
• 2005

A method for determination of toluene diisocyanates (TDI) in toluene diisocynate (TDI)-based polyurethane (PUR) packing material was investigated, and also the migration of TDI to food was studied. TDI was extracted using food simulants such as n-haptane and 4% aqueous acetic acid. The determinations were performed using gas chromatography/mass spectrometry (GC/MS). One of major components for polyurethane, toluene diisocyanates, were detected in ten samples among twenty six food contact materials with the concentration range of $0.51{\sim}60.88{\mu}g/ml$. However the highest extracted amount was just 0.7% of $60.88{\mu}g/ml$ if the contact surface of food packing for extracting liquid was limited to the outer layer without exposure of the cutting edge of food packing multi-layers. The result of this study and the analysis method for TDI diisocyanate will be very useful for further study about food contact material, and the monitoring result could be used for evaluating the safety of food contact material before it is to be used for food, preservation.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.08a
• /
• pp.250-250
• /
• 2013

단일벽 탄소나노튜브(Single-walled nanotubes, SWNTs)는 나노스케일의 크기와 우수한 물성으로 인하여, 전자, 에너지, 바이오 분야로의 응용이 기대되고 있다. 특히 SWNTs의 직경을 제어하게 되면 튜브의 전도성 제어가 훨씬 수월하게 되어, 차세대 나노전자소자의 실현을 앞당길 수 있으며 이러한 이유로 많은 연구들이 현재 행해지고 있다. SWNTs의 직경제어 합성을 위해서는 현재 열화학기상증착법(Thermal chemical vapor deposition; TCVD)이 가장 일반적으로 이용되고 있으며, 합성 촉매와 합성되는 튜브의 직경과의 크기 연관성이 알려진 후로는, 촉매의 크기를 제어하여 SWNTs의 직경을 제어하고자 하는 연구들이 활발하게 보고되고 있다. 특히, 촉매 나노입자의 직경이 1~2 nm 이하로 감소될 경우, SWNTs의 직경 분포가 어떻게 변화할 것인지가 최근 가장 중요한 관심사로 남아 있으나, 이러한 크기의 금속입자는 나노입자의 융점저하 현상이 발현되는 영역이므로, SWNTs의 합성온도 영역에서 촉매 금속입자는 반액체(Semi-liquid) 상태로 존재할 것으로 추측하고 있다. 본 연구에서는 고온의 SWNTs 합성환경에서 금속나노촉매의 유동성을 제한하기 위하여 나노사이즈의 기공이 규칙적으로 정렬된 다공성 물질인 제올라이트를 촉매담지체로 이용하였고, 이 때 다양한 합성변수가 SWNTs의 직경에 미치는 영향을 살펴보고자 하였다. SWNTs의 합성을 위해 실리콘 산화막 기판 위에 제올라이트를 도포한 후, 합성 촉매로서 전자빔증발법을 통하여 수 ${\AA}$에서 수 nm 두께의 철 박막을 증착하였다. 합성은 메탄을 원료가스로 하여 TCVD법으로 실시하였다. 주요변수로는 제올라이트 종류, 증착하는 철 박막의 두께, 합성온도를 설정하였으며, 이에 따라 합성된 SWNTs의 합성수율 및 직경분포의 변화를 체계적으로 살펴보았다. SWNTs의 전체적인 합성수율의 변화는 SEM 관찰결과를 이용하였으며, SWNTs의 직경은 AFM 관찰 및 Raman 스펙트럼의 분석에서 도출하였다. 실험결과, 제올라이트 종류에 따라서는 명확한 튜브직경 분포의 변화 없이 비교적 좁은 직경분포를 갖는 SWNTs가 합성되었으며, 합성온도가 $850^{\circ}C$ 이하로 감소되면 합성수율이 현저히 감소되는 것을 알 수 있었다. 촉매박막의 두께가 1 nm 이상인 경우에서는 직경 5 nm 전후의 나노입자가 형성되었으며, 이때 SWNTs의 합성수율은 높았으나 다양한 직경의 튜브가 합성이 된 것을 확인할 수 있었다. 반면, 촉매입자의 크기가 2 nm 이하에서는 합성수율은 다소 저하되었으나, SWNTs의 직경분포의 폭이 상대적으로 훨씬 좁아지는 것을 알 수 있었다. 추후, 극미세 촉매와 저온합성 환경에서의 합성수율 향상을 위한 합성공정의 개량이 지속적으로 요구된다.

• Weed & Turfgrass Science
• /
• v.5 no.4
• /
• pp.260-267
• /
• 2016

Amino acids in the plant were intermediate metabolites which produced by uptake and assimilation of nitrogen and these extracts which gained by bio-chemical digestion from protein of plant or animal were a source of functional fertilizer. This study was conducted to evaluate effects of keratin amino acid fertilizer (KAF) gained from animal hair or hoof on changes of turfgrass quality and growth by investigating turf color index, chlorophyll index, shoot number, clipping yield, and nutrient content in the turfgrass tissue. Treatments were designed as follows; non-fertilizer (NF), compound fertilizer (CF), keratin amino acid fertilizer treatments [CF + KAF $0.26ml\;m^{-2}$ (CKF), CF + KAF $0.52ml\;m^{-2}$ (2CKF)], and only keratin amino acid fertilizer treatment (KF). Shoot number, clipping yield, and nitrogen uptake of KF were higher than those of CF. As compared with CF, soil chemical properties, turf color index, chlorophyll index and clipping yield of keratin amino acid fertilizer were not significant, but shoot number and uptake of N and K were increased significantly. These results show that the application of keratin amino acid fertilizer increased shoot number and growth by increased uptake of nitrogen and potassium.

• The Korean Journal of Petroleum Geology
• /
• v.14 no.1
• /
• pp.45-52
• /
• 2008

The GTL(Gas to Liquids) technology, manufacturing synthesized oil from natural gas, had been developed about 1920 for the military purpose by Fischer and Tropsch, German scientists. And 1960, Sasol company had started commercializing the FT(Fischer-Tropsch) synthesis technology, for the transport fuel in South Africa. Until a recent date, the commercialization of GTL technology had been delayed by low oil price. But concern about depletion of petroleum resources, and development in synthesizing technology lead to spotlight on the GTL businesses. Especially, Qatar, which has rich natural gas fields, aims at utilizing natural gas like conventional oil resources. Therefore, around this nation, GTL plants construction has been promoted. There are mainly 3 processes to make GTL products(Diesel, Naphtha, lube oil, etc) from natural gas. The first is synthesis gas generation unit reforming hydrogen and carbomonoxide from natural gas. The second is FT synthesis unit converting synthesized gas to polymeric chain-hydrocarbon. The third is product upgrading unit making oil products from the FT synthesized oil. There are quite a little sulfur, nitrogen, and aromatic compounds in GTL products. GTL product has environmental premium in discharging less harmful particles than refinery oil products from crude to the human body. In short, the GTL is a clean technology, easier transportation mean, and has higher stability comparing to LNG works.

• Journal of Animal Environmental Science
• /
• v.16 no.3
• /
• pp.215-226
• /
• 2010

The pig slurry leachate was dark brown-colored solution that leaches out of woodchip trickling filter. The purpose of this research was to investigate the effect of pig slurry leachate and byproduct on growth characteristics of leaf lettuce in hydroponics culture. The effects of addition of fish meal, bone meal and crab shell for the growth of leaf lettuce were investigated. Leaf lettuce were grown in each of six combination treatment solutions; slurry leachate, slurry leachate + fish meal, slurry leachate+bone meal, slurry leachate + crab shell and chemical hydroponic solution for lettuce based on EC content. The chemical nutrient solution was the solution of National Horticulture Research Station for the growth of lettuce. The all of nutrient solution was adjusted 1.5 mS/cm in EC in hydroponics culture. 1. The pH level of leachate of trickling filter was increased and EC decreased gradually during treatment. Pig slurry leachate was low in suspended solids (SS), phosphorus (P), but rich in potassium (K). 2. The plot of slurry leachate (SL) was lowest in the growth characteristics of lettuce. The leaf length and width of lettuce treated with mixture plot of slurry leachate and fish meal (SL + FM) was higher compared with plot in slurry leachate. The chlorophyll reading was reduced in plot treated with slurry leachate, but that in plot of SL+FM was similar compared with control plot. 3. The fresh weight of lettuce showed lowest in the plot treated with slurry leachate. The addition of fish meal increased the yield of comparing plot of slurry leachate, but plots of bone meal and crab shell addition were not significantly difference. The fresh weight of leaf lettuce in plot of SL+FM was 87% as 400.0g compared with control. In conclusion, the mixture solution of pig slurry leachate and fish meal could be used as a nutrition solution of organic lettuce hydroponics.