• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.678-684
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• 2005

Extraction conditions, spectrometric, and sensory properties of pigment extracts from green discolored garlic (GDG) were studied for development of green index to evaluate degree of green discoloration of garlic. GDG pigments were extracted using polar solvents, such as methanol, ethanol, and water. Methanol with 1% HCl resulted in highest extraction of green pigments. Extraction of pigments was affected by temperature, and extracted pigments were partially destroyed at high temperatures. Optimum conditions for extraction of green pigments were $20^{\circ}C$ for 30 min. Because green pigments are unstable at room temperature, and no method has been reported to evaluate degree of green discoloration of garlic, color chart was designed by mixing varying amounts of control and GDG. High correlation was observed between sensory scores and "a" value of color chart samples (y=-3.465x - 11.676) with $R^2$ of 0.993. Green index (GI) was developed based on linear regression equation between sensory scores and "a" values. Sensory panel recognized green discoloration of garlic at $GI{\geq}3.0$. GI developed in this study could be utilized to evaluate degree of green discoloration of garlic during cold storage and distribution of garlic.

• KSBB Journal
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• v.23 no.6
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• pp.557-560
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• 2008

The micelle process was developed for pre-purifying paclitaxel from plant cell cultures of Taxus chinensis, giving a high purity and yield. The approach in this work was to transfer paclitaxel in the crude extract to an aqueous surfactant solution as a micelle, allowing organic solvents to be used for removal of lipids and non-polar impurities. In this work, the effects of various surfactants such as CPC, CTMAC, LTMAC, SDS, AOT, Tween, PEG, and Triton were examined on the yield, purity, and phase separation time in micelle process. Among these surfactants, CTMAC (5%, w/v) gave the best result in terms of paclitaxel yield (${\sim}99%$), purity (${\sim}21%$), and phase separation time (30 min). The use of micelles in the pre-purification process allows for rapid and efficient separation of paclitaxel from interfering compounds and dramatically increases the yield and purity of crude paclitaxel for subsequent purification steps.

• Polymer(Korea)
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• v.28 no.4
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• pp.314-320
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• 2004

Soluble aromatic polyimides bearing 4-(4-oxyalkyleneoxystyryl)- pyridines (ethylene and hexylene) as photoreactive side groups were synthesized and characterized. The photoreactive polymers were soluble in various polar organic solvents and their films were easily formed by solution casting. The photoreactivities of the polymers in the film state were approximately 64% at an exposure energy of 1.5 J/$\textrm{cm}^2$. Transmittances of the polymer films were about 85% after annealing at 20$0^{\circ}C$. Therefore, these polymers can be evaluated to be photoreactive polyimides with good transparency and solubility. The dichroic ratios of the polymers with ethylene and hexylene groups as the alkylene spacers were 0.023 and 0.026, respectively. The order parameters of 4'-pentyl-4-bipheny1carbonitrile as a liquid crystal (LC) in the film cells of the former and latter polymers were 0.50 and 0.52, respectively. These results indicate that the polymers show the effect of alkylene spacer on the photoalignments. The LC in the film cells of the polymers was perpendicularly oriented to the electric vector of the linear polarized UV light (LPUVL).

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.528-534
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• 2011

This study was conducted to investigate the changes in saponin content and antioxidant activity of crude ginseng and extruded ginseng by using different solvent extraction methods. Each of the fractions was first extracted by 80% ethanol followed by ether treatment to remove the lipid components. Water soluble components were separated by ethylacetate and water saturated butanol. Four fraction, including 80% ethanol, ethylacetate, butanol and water were obtained from crude and extruded ginsengs to analyze saponin content and antioxidant activity. Saponin content and antioxidant capacity of each of the four fractions were measured by LC/MS analysis and ORAC(Oxygen Radical Absorbance Capacity) assay, respectively. It was found that a major portion of saponin was present in ethyl acetate and water saturated butanol fractions. When extracted by 80% ethanol, ginsenoside Rb1 and Rg1 were mostly found in crude ginseng, while ginsenoside Re and Rb1 were detected in extruded ginseng. Even though Rh1 and Rg3 were found in a very small quantity in crude ginseng, there was a significant quantity of both in extruded ginseng when extracted by 80% ethanol. Similar tendency was also observed in extruded ginseng fraction when extracted with ethyl acetate and butanol. In crude ginseng, the level of Rg1 was the highest among other ginsenosides upon extraction by ethyl acetate, while Rh1 and Rg3 were predominantly found by employing similar solvent extraction in the extruded ginseng. Also, Rg1, Re and Rb1 were also found in the extruded ginseng with small quantity. Rg1, Re and Rb1 were found in crude ginseng by butanol extraction, while Rb1 and Re were extracted from the extruded ginseng. Overall, there was no difference in the saponin content between crude ginseng and extruded ginseng when extracted by butanol and water, but twice as much of saponin was obtained by 80% ethanol extraction and 6 times more saponin were obtained in ethyl acetate fraction in the extruded ginseng. Antioxidant capacity of crude ginseng as determined by ORAC assay was higher in 80% ethanol(high in many different kinds of biological compounds) and water saturated butanol(high in polar saponin) fractions than the ethyl acetate and water fractions. No difference in antioxidant capacity was observed between crude and extruded ginseng. However, antioxidant capacity of ethyl acetate and water fractions in extruded ginseng was significantly higher than crude ginseng($P$ >0.05). All the fractions in both, crude and extruded ginseng possessed antioxidant capacity and even water fractions that contained almost no saponin had some antioxidant capacity. While determining correlation coefficient between fractions in extruded ginseng by Pearson correlation, it was observed that 80% ethanol fraction was in correlation with ethyl acetate($P$ >0.01) and ethanol($P$ >0.001) and in the case of ethylacetate, correlation was observed only with butanol fraction($P$ >0.05).

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.381-398
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• 1975

Present work was executed to evaluate effects of adjuvants. stabilizers. moisture. pH and heavy metals on the stability of Fenitrothion in the emulsifiable concentrate. In addition, susceptibility ' of Fenitrothion in various formulations, to UV-irradiation has been also examined. The results are summarized as follows; 1. Xylene and benzene were found to be satisfactory solvents for Fenitrothion emulsifiable concentrate. As expected, polar sol vents such as aliphatic alcohols considerably reduced stability of the pesticides. 2. Of the two non-ionic emulsifiers, an alkyl aryl type Sorpol-1200, in contrast to sorbitan type Tweens, substantially reduced decomposition of Fenitrothion in the emulsifiable concentrates. Moisture and pH of emulsifiers. in the ranges studied. affected little if any. on the stabi ity of the Fenitrothion during the experiment periods. 3. Maleic anhydride, p-toluene sulfonic acid, sulfosalicylic acid, maleic anhydride-sulfosalicylic acid reduced decomposition of Fenitrothion in the emulsifiable concentrate. Addition of organic acids, however, increased liability of Fenitrothion in the emulsifiable concentrate. 4. Presence of either zinc or copper metals in the emulsifiable concentrate containing Tween-80 as a emulsifier, reduced stability of the Fenitrothion. 5. UV-irradiation, as expected, brought decomposition of Fenitrothion. The liability of Fenitrothion formulations decreased in the order, wettable powder ${\gg}$ dust > emulsifiable concentrate.