• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.277.1-277.1
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• 2013

Molecular diagnostics consists of three processes, which are a sample pretreatment, a nucleic acid amplification, and an amplicon detection. Among three components, sample pretreatment is an important process in that it can increase the limit of detection by purifying nucleic acid in biological sample from contaminants that may interfere with the downstream genetic analysis such as nucleic acid amplification and detection. To achieve point-of-care virus detection system, the sample pretreatment process needs to be simple, rapid, and automatic. However, the commercial RNA extraction kits such as Rneasy (Qiagen) or MagnaPure (Roche) kit are highly labor-intensive and time-consuming due to numerous manual steps, and so it is not adequate for the on-site sample preparation. Herein, we have developed a rotary microfluidic system to extract and purify the RNA without necessity of external mechanical syringe pumps to allow flow control using microfluidic technology. We designed three reservoirs for sample, washing buffer, and elution buffer which were connected with different dimensional microfluidic channels. By controlling RPM, we could dispense a RNA sample solution, a washing buffer, and an elution buffer successively, so that the RNA was captured in the sol-gel solid phase, purified, and eluted in the downstream. Such a novel rotary sample preparation system eliminates some complicated hardwares and human intervention providing the opportunity to construct a fully integrated genetic analysis microsystem.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.54-59
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• 1997

After extracting Caridina denticulata denticulata, the raw material of salt-fermented Toha, with the use of water, ether, acetone and methanol in order, we had the antimicrobial activity test for nine strains of bacteria which are harmful to the human body and food. It is as follows; solvent extract yield of the powder of vacuum freeze dried Caridina denticulata denticulata was 52% of water fraction, 7.4% of ether fraction, 1.0% of acetone fraction and 0.8% of methanol fraction. The result of solvent extract antimicrobial search of Caridina denticulata denticulata said that with the sample of 20$\mu\textrm{g}$/disk, ether fraction resulted in clear one of 8~12mm, acetone fraction 8~12mm, methanol fraction 7~9mm and water fraction didn't have antimicrobial effect. The minimal inhibitory concentration of solvent extract of Caridina denticulata denticulata per area was that ether fraction was 250~500$\mu\textrm{g}$/$m\ell$, acetone fraction 125~500$\mu\textrm{g}$/$m\ell$ and methanol fraction 250~500$\mu\textrm{g}$/$m\ell$. The minimal bactericidal concentration of solvent extract per area of Caridina denticulata denticulata showed that ether fraction was 2, 500~10, 000$\mu\textrm{g}$/$m\ell$, acetone fraction 1, 250~10, 000$\mu\textrm{g}$/$m\ell$ and methanol fraction 5, 000~10, 000$\mu\textrm{g}$/$m\ell$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.668-673
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• 2015

The pacific oyster Crassostrea gigas has a desirable taste and flavor that differs from those of other fish and shellfish. In order to develop a high value-added product from individually quick-frozen oyster extract (IQFOE), we prepared an oyster sauce from IQFOE and characterized its volatile compounds using vacuum simultaneous steam distillationsolvent extraction / gas chromatography / mass spectrometry. The moisture, crude protein, crude ash, salinity, pH and volatile basic nitrogen contents of the oyster sauce were 60.6%, 8.2%, 9.2%, 9.3%, 5.7 and 21.0 mg/100 g, respectively. Seventy-six volatile compounds were detected in the cooked odor of the oyster sauce. These volatile compounds included 14 esters, including ethyl acetate, 13 nitrogen- containing compounds, including 2,4,6-trimethyl pyridine, 13 acids, including hexadecanoic acid, 12 alcohols, including ethyl alcohol and 6-methyl heptanol, 6 alkanes, 5 aldehydes, including benzaldehyde, 5 ketones, including 1-(2-furanyl)-ethanone, 4 furans, including 2-furancarboxaldehyde and 2-furanmethanol, 3 aromatic compounds, including d-limonene, and 1 miscellaneous compound. Esters, acids and nitrogen-containing compounds, and alcohols were the most abundant compounds in the odor of the cooked oyster sauce, with some aldehydes, ketones, and furans.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1686-1692
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• 2012

The antioxidative activity of Kalopanax pictus shoots extracted using five different methods, stirrer extraction (SE), ultrasonification extraction (USE), vacuum extraction (VE), reflux extraction (RE), and reflux extraction after ultrasonification extraction (RUE), was evaluated to determine the most effective extraction method. RUE showed the highest yield of extract, and total polyphenol and flavonoid content. Additionally, the RUE extract showed higher antioxidative activity than that of the other extracts based on DPPH and ABTS free radical scavenging (90.85%, 99.83%), reducing power activity (OD 0.95, 700 nm), nitrite scavenging activity (55.46%), and ferrous ion chelating effect (45.12%).

• Korean journal of food and cookery science
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• v.28 no.1
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• pp.25-32
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• 2012

This study was carried out to evaluate biological activities concerning extracts according to extraction methods from unripened fruit of Rubus coreanus Miq. The extraction methods were HWE (hot water extraction for 4 hr at $100^{\circ}C$), SFE (extraction for 3 hr at $40^{\circ}C$ under 300 bar, 100% of $CO_2$ fluid), USE (ultrasonification extraction for 4 hr at $50^{\circ}C$ with water), USE+HWE (hot water extraction for 2 hr at $100^{\circ}C$ after ultrasonification process for 2 hr), VE (vacuum extraction for 4 hr at $90^{\circ}C$ under 0.9 bar with water). VE extract showed the highest contents of total polyphenol ($178.78{\pm}3.79\;mg/g$) and total flavonoid ($40.93{\pm}0.68\;mg/g$). $IC_{50}$ values of DPPH radical scavenging activity, linoleic acid peroxidation inhibition activity and LDL (low density lipoprotein) oxidation inhibition activity of HWE extract showed the lowest $35.39{\pm}0.25{\mu}g/mL$, $12.61{\pm}0.31{\mu}g/mL$ and $1.31{\pm}0.02{\mu}g/mL$ among other all extracts, respectively. $IC_{50}$ values of ${\alpha}$-glucosidase inhibitory activities of VE and HWE extracts showed lower $14.34{\pm}0.20{\mu}g/mL$ and $15.83{\pm}0.20{\mu}g/mL$ than those of other extracts, respectively. Specifically, HWE and VE extracts have relatively better biological activities than other extracts; these could be potentially used as a bioactive source for health functional foods.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.2
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• pp.103-112
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• 2009

Objectives : This study was to evaluate the pharmacological effect of Korea Red Ginseng aqueous extract (KRGE) on serum-deprived apoptosis of neuronal-like pheochromocytoma PC12 cells and to investigate its underlying action mechanism. Methods : KRGE was prepared by extracting Korea Red Ginseng with hot water and concentrating using a vacuum evaporator. Cell viability was determined after incubation of cells with KRGE or chemical inhibitor in serum-deprived medium for 60 h by counting intact nuclei following lysing of the cell membrane. Caspase activities were measured using chromogenic substrates and signal-associated protein phosphorylation and cytochrome c release were determined by Western blot analyses using their specific antibodies. Results : Serum deprivation induced PC12 cell death, which was accompanied by typical morphological features of apoptotic cell, such as nuclear fragmentation, caspase-3 activation, and cytochrome c release. This apoptotic cell death was significantly inhibited by KRGE and caspase-3 inhibitor, but not by the addition of NMA, ODQ, and PD98059. KRGE promoted phosphorylation of Akt and Bad, and this phosphorylation was inhibited by the PI3K inhibitor LY92004. In addition, this inhibitor also reversed KRGE-mediated protection of PC 12 cells from serum deprivation. These results suggested that KRGE protects PC12 cells from serum deprivation-induced apoptosis through the activation of PI3K/Akt-dependent Bad phosphorylation and cytochrome c release, resulting in caspase-3 activation. Conclusions : KRGE should be considered as a potential therapeutic drug for brain diseases including stroke induced by apoptosis of neuronal cells.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.808-811
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• 2001

Performance of pilot plant scale extraction and concentration of purple-fleshed sweet potato anthocyanin pigment was tested and the characteristics of pigment extracts and concentrates were investigated. Fifty kilograms of purple-fleshed sweet potato was extracted with 500 L of 1% citric acid in 20% ethanol. As a whole, extraction pattern of the large scale extraction was similar to that of the laboratory scale extraction. The extracted pigment solution was filtered twice with a bag filter and a winding type microfilter and the filtrate was concentrated by a large scale vacuum evaporator at $40^{\circ}C$ and 600 mmHg vac. The mean values of total optical density (TOD) of the extract and the concentrate were 6.53 and 120.45, respectively. Browning index (BI) and Degradation index (DI) of extract were 5.86 and 1.55 and those of concentrate were 5.89 and 1.56, respectively, which indicated that the pigments were not changed or degraded through the extraction and concentration process.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.237.1-237.1
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• 2014

Etching is one of the most important steps in semiconductor manufacturing. In etch process control a critical task is to stop the etch process when the layer to be etched has been removed. If the etch process is allowed to continue beyond this time, the material gets over-etched and the lower layer is partially removed. On the other hand if the etch process is stopped too early, part of the layer to be etched still remains, called under-etched. Endpoint detection (EPD) is used to detect the most accurate time to stop the etch process in order to avoid over or under etch. The goal of this research is to develop a hardware and software system for EPD. The hardware consists of an Optical Plasma Monitor (OPM) sensor which is used to continuously monitor the plasma optical emission intensity during the etch process. The OPM software was developed to acquire and analyze the data to perform EPD. Our EPD algorithm is based on the following theory. As the etch process starts the plasma generated in the vacuum is added with the by-products from the etch reactions on the layer being etched. As the endpoint reaches and the layer gets completely removed the plasma constituents change gradually changing the optical intensity of the plasma. Although the change in optical intensity is not apparent, the difference in the plasma constituents when the endpoint has reached leaves a unique signature in the data gathered. Though not detectable in time domain, this signature could be obscured in the frequency spectrum of the data. By filtering and analysis of the changes in the frequency spectrum before and after the endpoint we could extract this signature. In order to do that, first, the EPD algorithm converts the time series signal into frequency domain. Next the noise in the frequency spectrum is removed to look for the useful frequency constituents of the data. Once these useful frequencies have been selected, they are monitored continuously in time and using a sub-algorithm the endpoint is detected when significant changes are observed in those signals. The experiment consisted of three kinds of etch processes; ashing, SiO2 on Si etch and metal on Si etch to develop and evaluate the EPD system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1053-1058
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• 1998

Volatile flavor compounds in salt fermented big eyed herring were analyzed by vacuum simultaneous distillation solvent extraction/gas chromatography/mass spectrometry/olfactometry and aroma extract dilution anlaysis. A total of 44 volatile compounds were detected by GC/O analysis. Of these, 23 were positively identified, and composed of aldehydes(7), esters(5), ketones(4), sulfur containing compounds (3), aromatic hydrocarbons(2), alcohol(1) and nitrogen containing compound(1). Predominant odorants (Log3FD$\geq$5) in sample were ethyl butanoate(bubble gum /sweet candy-like), 3 methylbutyl butanoate (almond /nutty), 1 octen 3 one(earthy/mushroom like), (E,E) 2,6 nonadienal(roasted wheat/grainy), dimethyl trisulfide(soy sauce /cooked cabbage like), 2 acetylpyrazine(nutty/baked potato like) and unidentified compound(RI=1867, seaweed like).

• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.88-93
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• 1991

The biodegradable bacteria for fats and oils were isolatcd from soil and wastewater. The isolated strain was designated as LW-27 which had high COD removal rate and biodegr2idability on fats and oils, and was identified as pseudomonas chlrorapihis. The cell viability of LW-27 which produced by vacuum drying at $45^{\circ}C$ for 24 hours was 82%. When the wastewater was mixed with LW-27 agent (0.1g/ day) on the activated sludge unit, the removal rates of COD, BOD and n-hexanc extract of the effluents were about 92.9%, 94.8% and 98.0%, respectively.