• Journal of the Korea Academia-Industrial cooperation Society
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• 제17권6호
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• pp.9-17
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• 2016

A purification method was established for high-purity chondroitin sulfate from skate cartilage. Hydrolytic extraction of skate backbone cartilage was investigated with the proteases alcalase and protamex, and the extraction contents of chondroitin sulfate were measured with several physicochemical processes. The yield of extract from skate cartilage with $40^{\circ}Brix$ concentration was 23.3% with 2% alcalase hydrolysis, which was decreased to 8.47% and 3.37% with the first and second additional ethanol purifications, respectively. The yield was 16.62% with one ethanol purification after hydrolysis with a mixture of 1% alcalase and 1% protamex. The content of chondroitin sulfate was measured as 39.88-45.08% with different ratios of ethanol solvent. The content was 42.92% at a solvent ratio of 1:1 with alcalase protease and 45.08% with a ratio of 1:2 using a protease mixture of alcalase and protamex. The molecular weight range of chondroitin sulfate was about 110-310 thousand Da, and the purity of chondroitin sulfate was 24.87-49.92% with a mixture of alcalase and protamex in GPC analysis. The maximum purity of chondroitin sulfate was 53.93% after ultrafiltration. The odor strength of chondroitin sulfate was decreased by 33% and 38% after ethanol purification and additional filtration with activated carbon, respectively. The odor concentration of ammonia and TMA from chondroitin sulfate was decreased by 52.1% and 37.89% with activated carbon filtration and two ethanol purifications, respectively, but it was necessary to eliminate the odor components efficiently using additional physicochemical processes.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제50권spc1호
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• pp.181-186
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• 2005

This experiment was conducted to know the appropriate methods for extraction and determination of rutin contained buckwheat plants. The efficient HPLC analytical condition of rutin contained buckwheat plants was developed. The gradient elution employed a $250mm\times4.6mm$ i.d. Tosoh ODS 120T column. The gradient system was used two mobile phases. A gradient elution was performed with mobile phase A, consisting of $2\%$ Acetic $acid-45\%$ Acetonitrile, and mobile phase B, comprising $2\%$ aqueous acetic acid, and delivered at a flow rate of 1mL/min as follows: 0-18 min, $50-100\%$ A; 18-20 min, $100-50\%$ A; 20-22 min, $50\%$ A. The UV detection wavelength was set at 355 nm. The limit of detection (LOD) for rutin standard compound was 20 ng/mL. And, the higher content of rutin in the extracts was obtained by $80^{\circ}C$ reflex extraction for 120 min. from plants of buckwheat using ethanol.

• Journal of the Korean Society of Food Science and Nutrition
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• 제37권11호
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• pp.1491-1496
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• 2008

Twenty natural plants from Jeju were extracted by pressurized organic solvent (100% methanol, $40^{\circ}C$, 13.6 MPa, 10 min). Extraction yield, total phenolic content (TPC) and integral antioxidant capacity were measured, and each component was identified by GC/MS. Extraction yields were high as 21.8%, 21.5, 21.1, 20.7 and 20.1% in Rhus javanica, Euscaphis japonica, Alnus firma, Sapium japonicum and Sorbus alnifolia, respectively. The extracts containing high TPC (mg GAE/g of dry sample) were obtained from Malus sieboldii (68.3), Sapium japonicum (57.6), Pyrrosia lingua (56.6) and Euscaphis japonica (55.1). Integral antioxidant capacities of water-soluble substances were 598, 394, 293 and $270\;{\mu}mol$ ascorbic acid equivalent/g in Geranium thunbergii, Sapium japonicum, Cornus kousa and Rhus javanica, respectively. Integral antioxidant capacities of lipidsoluble substances were 611, 314, 296 and $242\;{\mu}mol$ trolox equivalent/g in Ardisia crenata, Ostrya japonica, Geranium thunbergii and Quercus acuta, respectively. Fifteen major peaks were identified by GC/MS from the extract of pressurized organic solvent from Sapium japonicum. Two polyphenols (gallic acid (retention time (RT) 19.7 min)) and quercetin (33.5 min)), ascorbic acid (RT 35.3 min), and several fatty acids (retention time 18.6, 21.0, 21.8, 21.9 and 23.6 min) were identified, and gallic acid was the major polyphenol component due to high peak area.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제7권6호
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• pp.1313-1318
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• 2006

The mechanism fur the surface film formation was studied by in situ Atomic Force Microscopy (AFM) observation of a highly oriented pyrolytic graphite (HOPG) basal plane surface during cyclic voltammetry at a slow scan-rate of 0.5 mV $s^{-1}$ in 1 moi $dm^{-3}$ (M) $LiPF_6$ dissolved in a mixture of ethylene carbonate (EC) and diethyl carbonate (DEC). Decomposition of the electrolyte solution began at a potential around 2.15 V vs. $Li^+$/Li on step edges. In the potential range 0.95-0.8 V vs. $Li^+$/Li, flat areas (hill-like structures) and large swelling appeared on the surface. It is considered that these two features were formed by the intercalation of solvated lithium ions and their decomposition beneath the surface, respectively. At potentials more negative than 0.80 V vs. $Li^+$/Li, particle-like precipitates appeared on the basal plane surface. After the first cycle, the thickness of the precipitate layer was 30 nm. The precipitates were considered to be decomposition of the lithium salt ($LiPF_6$) and solvent molecules (EC and DEC), and to have an important role in suppressing further solvent decomposition on the basal plane.

• Journal of Conservation Science
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• 제9권1호
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• pp.40-47
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• 2000

Dimension stability was examined after PEG pretreatment and post freeze-drying treatment in order to determine the PEG(#3350) concentration and solvent for pre-treatment of freeze-drying of highly-degraded waterlogged ash woods(Fraxinus spp.; ca. 5,700 BP) excavated from peat lands at Pyungtack, Kyounggi-do. At the low concentration (<30-40%) of PEG soaking in both water and t-butanol, the weight increases abruptly, but at high concentration (>50%) gradually, consequently, taking longer treatment time. PEG loading was higher in t-butanol solution than in water. However, the best dimesional stability was obtained from freeze-drying after lower PEG solution (40% in water) soaking. Low dimensional stability, found in the samples treated with higher PEG solutions (60%-70% in t-butanol), might come from incomplete freezing and excess PEG absorbing moisture. The samples air-dried after 70% PEG treatment had collapse defects. In conclusion, the use of low concentration (about 40% in water) PEG solution was the most suitable pretreatment for freeze drying of highly-degraded waterlogged ash woods.

• Journal of Sericultural and Entomological Science
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• 제27권1호
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• pp.24-30
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• 1985

The effect of some organic solvents on interrupting diapause of Bombyx mori eggs was examined to provide a clue to the mechanism of diapause initiation. Methyl alcohol and benzene proved to be efficient in developing the prospective diapause eggs upto the stage of hatching or body pigmentation of the embryos. On the other hand, most of the eggs soaked in chloroform and mixture solution of chloroform-methyl alcohol (2:1) died in the early embryonic developmental stage with yellow or red brown colours, and the egg weights decreased upto ca. 40% of the original weight 8 days after the treatments. Methyl alcohol treatment for 2, 5 and 10 min to the 5hr-old-eggs led to empergence of the larvae, with high incidence (70∼80%) in the race of Kumchu X Chonghwa and with low indidence (1∼4%) in Daezo. The effect of same treatment to 20hr old eggs decreased to ca. 10% in the emergence of larvae in Kumchn X Chonghwa and increased to 20∼30% in Daezo, while the effect disappeared shortly after the diapause initiation (48hr-old-eggs). Considering the high dependency upon the egg age of the sensitivity to solvents, it was supposed that initiation and termination of diapause may be controlled by different mechanism. It was also suspected that the solvents exert their effect on the permeability of the eggshell.

• Korean Journal of Food Science and Technology
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• 제35권5호
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• pp.777-782
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• 2003

Response surface methodology (RSM) was used to monitor the characteristics of ethanol extracts from Hericium erinaceus. A central composite design was applied to investigate the effects of independent variables, ethanol concentration $(X_1)$, and sample ratio $(X_2)$ on dependent variables, soluble solid $(Y_1)$, total phenols $(Y_2)$, crude protein $(Y_3)$, electron donating ability $(Y_4)$, and browning color $(Y_5)$ of the extracts. As the sample ratio increased, the soluble solid content increased. Ethanol concentration played a minor role. Total phenols and crude protein increased with sample ratio. Sample ratio had a greater effect than alcohol concentration in the extraction of soluble solid, total phenols, crude protein, and browning color, with an exception of electron donating ability. The optimum ranges at 2 hr extraction was $3.9{\sim}5.0\;g/l00\;mL$ in sample ratio and $36{\sim}52%$ in ethanol concentration. Predicted values at the optimized conditions were acceptable when compared to experimental values.

• Journal of the Korean Chemical Society
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• 제39권4호
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• pp.237-243
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• 1995

The measurments of neutral semiquinone radicals, which were formed from the laser flash photolysis of anthraquinone (AQ) in the mixed solvents were carried out by the time resolved electron spin resonance (trESR) spectroscopy. The chemically induced dynamic electron polarization (CIDEP) spectra of the neutral semiquinone radical (AQH${\cdot}$) and semiquinone radical anion (AQ${\cdot}$-) were successively detected in the laser flash photolysis of AQ in the mixtures of 2-propanol (PrOH) and triethylamine (TEA). The neutral semiquinone radical was short-lived with the half-life of 0.8 ${\mu}sec$, whereas the semiquinone radical anion was relatively stable and then its cwESR could be observed. The rate constant of the spin-depolarization of semiquinone radical anion was $2.6{\times}10^5 sec^{-1}$ and the decay of the radical anion was the first order reaction with the rate constant of $3.0{\times}10^2\; sec^{-1}$. No CIDEP of semiquinone radical anion was observed in the mixture of PrOH and the lower concentration of TEA than 2 percent. The CIDEP spectrum of the neutral semiquinone radical was detected in the mixture of benzene and TEA with the half-life of 3.0 ${\mu}sec$. The neutral semiquinone radical could not be detected by cwESR. Neither CIDEP nor ESR absorption could be observed in PrOH, TEA or benzene only.

• Journal of the Korean Society of Food Science and Nutrition
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• 제35권1호
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• pp.1-6
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• 2006

Through the application of a microwave-assisted extraction, the aim of study was to investigate the extraction conditions for the total yield, electron donating ability, total polyphenol contents and nitrite scavenging effect from Pleurotus eryngii. This experiment was conducted under the following extraction conditions: the microwave power (60, 90, 120 W), sample to solvent ratio (1:50, 1:20, 1:10), extraction time (1, 5, 10, 15 mins), and extractant like water, $50\%$ EtOH and $99\%$ EtOH. During the increase of microwave power ranging from 60 to 120 W, the maximized effective components were obtained when the microwave power was set at 60 W. By decreasing the ratio down to 1:10 (g/mL), the extraction of effective components but not total yield was the highest at 1:10 (g/mL). As going up to 15 min, the maximum extraction of effective components was achieved at 1 min for the extraction time and was little affected at over 5 min. In conclusion, the most appropriate conditions for the extraction of effective compounds from Pleurotus eryngii were as follows: the microwave power at 60 W, 1:10 of the sample to solvent ratio, extraction time at 1 min and water as the extractant.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제66권4호
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• pp.326-338
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• 2021

Ultra-performance liquid chromatography (UPLC) was used to assess the hordein protein fraction of malting barley. C-hordeins (barley prolamins) were extracted with 70% ethanol (EtOH) and 55% isopropyl alcohol (IPA, 2-propanol), and B-hordeins were extracted with the same alcohols in 1.0% dithiothreitol (DTT). High molecular weight (HMW) prolamins (D-hordeins) were extracted with 50% IPA with 1M Tris-HCl (pH 8.0). The same protein patterns were observed in both the experimental extraction solutions (EtOH and IPA). However, the patterns of hordein, extracted with EtOH and IPA containing 1.0% DTT, differed slightly. C- and B-hordeins extracted from those solutions were analyzed. Twenty-six malting barley varieties developed in Korea were analyzed using UPLC. The varieties were divided into seven groups according to hordein patterns of retention time 16 min to 18 min, and 20 varieties showed unique patterns.