• Bulletin of the Korean Chemical Society
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• v.24 no.9
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• pp.1293-1302
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• 2003

Rate constants at various temperatures and activation parameters are reported for solvolyses of acyl chlorides (RCOCl), with R = Me, Et, i-Pr, t-Bu, cyclopentylmethyl, benzyl, thiophenylmethyl, 2-phenylethyl, diphenylmethyl, and phenylthiomethyl in 100% ethanol, 100% 2,2,2-trifluoroethanol (TFE), 80% v/v ethanol/ water and 97% w/w TFE/water. Additional rate constants for solvolyses with R = Me, t-Bu, and $PhCH_2$ are reported for TFE/water and TFE/ethanol mixtures, and for solvolyses with R = t-Bu, and PhCH2 are reported for 1,1,1,3,3,3-hexafluoropropan-2-ol/water mixtures, as well as selected kinetic solvent isotope effects (MeOH/MeOD and TFE). Taft plots show that electron withdrawing groups (EWG) decrease reactivity significantly in TFE, but increase reactivity slightly in ethanol. Correlation of solvent effects using the extended Grunwald-Winstein (GW) equation shows an increasing sensitivity to solvent nucleophilicity for EWG. The effect of solvent stoichiometry in assumed third order reactions is evaluated for TFE/ethanol mixtures, which do not fit well in GW plots for R = Me, and t-Bu, and it is proposed that one molecule of TFE may have a specific role as electrophile; in contrast, reactions of substrates containing an EWG can be explained by third order reactions in which one molecule of solvent (ethanol or TFE) acts as a nucleophile, and a molecule of ethanol acts as a general base catalyst. Isokinetic relationships are also investigated.

• Food Science and Preservation
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• v.14 no.1
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• pp.67-72
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• 2007

To prepare useful foods from Acanthopanax koreanum, extraction of major constituents by water and ethanol solutions were investigated Reflux extractions of 300 g of dried material of particle size less than 0.5 cm, were carried out in 7.5 L of water, or ethanol solutions (30 -95% v/v) for 9 hr at $100^{\circ}C$. The pH values of extracted solutions were 4.0-6.5. The Color b-value of extracted solutions increased as ethanol concentrations dropped and with longer extraction times. The amounts of material in extracts increased rapidly in the first 2-3 hr of extraction. The extract levels from 30-70% ethanol solutions were 0.27-0.47 g/100 g. The main free sugars of extract were sucrose, fructose and glucose. Eleutherosides were extracted rapidly (within 3 hr), and eleutheroside extraction was best in water or in 30-70% ethanol 95% ethanol solutions were less effective. The eleutherosides were extracted to 97% by water or 30-70% ethanol solutions after 3-5 hr. Acanthoic acid extraction was more affected by ethanol level than by extraction time water achieved only trace extinction. In summary, reflux extraction in 40-70% ethanol for 3-5 hr was adequate for the extraction of functional materials from Acanthopanax koreanum.

• Journal of Ginseng Research
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• v.10 no.1
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• pp.80-93
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• 1986

The tail portion of dried 6-year old white ginseng was extracted and sugars and nitrogen compounds were also evaluated for chemical properties depending on varying conditions of extractions. The factors studied were extraction temperature in the range of 70-$100^{\circ}C$, ethanol concentration of 0-90% and the times of extractions which was taken 8 hours per each extraction in water at $80^{\circ}C$. For the effect of ethanol concentration in the extraction solvent, it was found that the amounts of free, reducing and total sugars and starch recovered in extract were almost linearly decreased along with the increase of concentration and the nonprotein nitrogen accounted over 84% of total nitrogen in extract. As ethanol concentration became increased, extractions of total nitrogen and water souluble nonprotein nitrogen were decreased especially in 90% ethanol. For the extraction temperature, all the sugar fractions with water and 70% ethanol except free sugar have tended to increase along with the temperature raised from 70 to $100^{\circ}C$ and it was found there is little changes of nitrogen compounds in the temperature range except a rapidly increase in water soulble protein at $100^{\circ}C$. For the times of extractions, showed that most of extractable compounds were extracted in 3 times of extractions with water at $80^{\circ}C$. It was shown that more than 95f) of sugars and 80% of nitrogen compounds were yielded with water extraction. Accordingly it was efficient to extract with water or 70% ethanol in 3 times in terms of !actor and energy consumption.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.33-38
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• 2006

This study was performed to provide basic rheological data of dandelion root concentrates in order to predict their processing aptitude and usefulness as functional foods material. The hot water and 70% ethanol extracts of dandelion root were concentrated at 5, 20, and 50 Brix, and their static viscosity, dynamic viscosity, and Arrhenius plots were investigated. Almost all hot water concentrates showed the typical flow properties of a pseudoplastic fluid, but evaluation using the power law model indicated that the 70% ethanol concentrates showed a flow behavior close to a Newtonian fluid. The apparent viscosity of hot water and 70% ethanol concentrates decreased with increasing temperature. Yield stresses of hot water and 70% ethanol concentrates by Herschel-Bulkley model application were in the range of 0.026 - 1.368 Pa and 0.022 - 0.238 Pa, respectively. The effect of temperature and concentration on the apparent viscosity was examined by Arrhenius equation. The activation energies of hot water and 70% ethanol concentrates were in the range of $8.762-23.778{\times}10^3\;J/mol{\cdot}kg$ and $3.217-20.384{\times}10^3\;J/mol{\cdot}kg$ with increasing concentration, respectively. Storage (G') and loss (G") moduli were generally increased with increasing frequency. For the 70% ethanol concentrates, G" predominated over G' at all applied frequencies and so they showed the typical flow behavior of a low molecular solution. However, for the hot water concentrates, G' predominated over G" at more than 1.9 rad/sec (cross-over point) and so they showed the typical flow behavior of a macromolecular solution.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.317-320
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• 2004

Physiological effects of curcumin, major yellow-colored pigment in tumeric (Curcuma longa L.), extracted by traditional extracting methods, ethanol and hot-water extractions, and supercritical fluid extraction (SFE) using supercritical carbon dioxide as new extracting method. Antioxidative activity of ethanol extract was higher than those of SFE and hot-water extracts. Results of Ames mutagenicity test on SFE, ethanol, and hot-water extracts revealed no mutagen in the extracts. Antimutagenicity rates of SFE, ethanol, and hot-water extracts against direct mutagen, 2-nitrofluorene (2-NF), were 20.1, 9.3, and 15.2%, respectively. Antimutagenicity rate of SFE extract against TA98 derived from indirect mutagen, 2-acetamidofluorene (2-AF), was 12.2%, whereas none was observed in ethanol and hot-water extracts. Nitrite-scavenging ability of SFE extract was higher than those of ethanol and not-water extracts.

• Korean journal of food and cookery science
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• v.30 no.6
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• pp.785-791
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• 2014

The antioxidative activities of beverages with water or ethanol extracts from Maegmundong (Liriope platyphylla) were investigated with free amino acid and mineral analysis, as well as saponin, total phenolics and flavonoid determination. Antioxidative activity was evaluated by electron donating ability and ABTS radical scavenging activity. There was only a small difference between water extract beverages and ethanol-extract beverages with respect to their electron donating ability and ABTS radical scavenging activity, although the total saponin, total phenolics and flavonoid were found to be greater in the ethanol extract beverages than in the water extract beverages. Three major free amino acids of the Magemundong beverages with water- or ethanol extract were asparagine (58.30, 60.68 mg%), methionine (15.10, 13.95 mg%, respectively) and proline (12.31, 14.00 mg%, respectively). The most abundant mineral in the Maegmundong beverage with water and ethanol extract was potassium (238.68, 244.32 mg%, respectively).

• The Korea Journal of Herbology
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• v.28 no.3
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• pp.45-51
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• 2013

Objectives : This study was conducted to measure the antioxidative and antimicrobial activities of water- and ethanol-extracts from Betula platyphylla var. japonica, Punica granatum and Rhus javanica against various species of anaerobic bacteria. Methods : In order to evaluate the antioxidative and antimicrobial activities of water- and ethanol-extracts, DPPH radical scavenging and superoxide dismutase (SOD)-like activities were measured in various species such as Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans and Propionibacterium acnes that induce skin inflammation. Also the total amount of phenol in each water- and ethanol-extract was measured to identify its role in the antioxidative and antimicrobial activities of water- and ethanol-extracts from Betula platyphylla var. japonica, Punica granatum and Rhus javanica. The antibacterial activity of the extracts was measured by confirming the lowest concentrations in disk diffusion and minimum inhibitory concentration (MIC) tests. Results : It was observed that RJE (Rhus javanica-EtOH extracts) show the highest content of total phenol. In addition, for RJE the total phenol content was higher from samples taken from domestic sources than from samples taken from foreign sources. DPPH radical scavenging activity was increased by treatment with PGE (Punica granatum-EtOH extracts), RJE and RJW (Rhus javanica-water extracts). It was observed that SOD-like activity was highest in the treatment with PGE. All of the extracts showed antimicrobial activity on S. epidermidis, S. aureus, P. acnes and E. coli, including those from Punica granatum, and it was noted that the activity was higher with RJE than with RJW. Conclusions : These results provide evidence that ethanol extracts of Punica granatum and Rhus javanica may have a beneficial role as antioxidants and antibiotics. Extracts from domestic samples of Betula platyphylla var japonica appeared to have a greater efficacy than extracts from foreign samples.

• Food Science and Preservation
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• v.14 no.3
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• pp.332-335
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• 2007

Hot water and 95%(v/v) ethanol extracts were prepared from dried Lespedeza cuneata seeds and antioxidant compounds were isolated by solvent fractionation, silica gel adslorption chromatography, Sephadex LH-20 column chromatography, and preparative HPLC. Antioxidant activity was measured using DPPH radical scavenging activity. The 80%(v/v)ethanol and ethylacetate fraction of Lespedeza cuneata seed extracts had stronger antioxidant effects than did the n-hexane fraction. The active antioxidant compounds obtained from hot water and 95%(v/v) ethanol extracts may be identical, based on analysis by Sephadex LH-20 column chromatography and preparative HPLC.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.6
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• pp.697-703
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• 2017

This study investigated the high-efficient process for bioethanol from barley by various condition. First, higher concentrations of ethanol could be produced without loss of yield by using reducing water consumption. This is because it could prevent to increase viscosity despite reducing water consumption. Second, the ethanol yield could be improved by using reducing particle size of biomass (increase of enzyme reactive surface). Third, The addition of protease could have a considerable effect on yield of fermentation, which provides nutrients to the yeast. This results showed that bioethanol production would provide efficient ethanol production and lower production costs.

• The Korean Journal of Food And Nutrition
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• v.13 no.2
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• pp.152-157
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• 2000

In order to select the optimum drying method for the production of cinnamon extract, water extract and 70% ethanol extract of cinnamon were prepared. And then several drying method of oven drying, vacuum evaporation, spray drying and freeze drying were performed. Content of cinnamic acid, cinnamic aldehyde, eugenol, tannin and free sugar, and antioxidant activity, degree of browning, pH, color value, turbity and solubility were compared. In water extract, contents of cinnamic acid, cinnamic aldehyde, eugenol were 29.45mg/100g, 94.86mg/100g, 120.75mg/100g and decreased to 4.76%∼44.21%, 5.30%∼48.05%, 3.66%∼21.83% by oven dyring, vaccum drying, spray drying respectively, but freeze drying showed a little decrease of those components. In 70% ethanol extract, effectual components decreased to 76.05%∼88.38% and 26.86%∼78.76% by freeze drying and vacuum evaporation respectively. Antioxidant activity decreased by drying and decreasing rate in 70% ethanol extract was lower than water extract. Degree of browning increased as the drying temperature increased. Tannin and free sugars were little affected by drying temperature. Solubility decreased in oven drying and 70% ethanol extract. Overall data suggested that optimum drying methods of cinnamon extract were freeze drying in case of water extract and freeze drying and vaccum drying in case of 70% ethanol extract.