• Korean journal of food and cookery science
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• v.18 no.4
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• pp.381-389
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• 2002

The purpose of this study was to select an ingredient acting as a natural emulsifier to retard the retrogradation of rice cake by the measurement of mechanical characteristics of the cakes. For the purpose, Backsulgi, the most basic type of rice cake, was prepared by adding various ingredients having high contents of lecithin such as raw soybean powder, parched soybean powder, soybean oil, egg yolk powder, and the measurements and observations on the chromaticity, swelling power, pore ratio and cross-section were made. In addition, changes in the textural characteristics of Backsulgi samples were determined while storing them at the temperatures of 4$^{\circ}C$ and 20$^{\circ}C$ for 0, 1, 2 and 3 days. The results of the study were as follows: 1. In terms of chromaticity, the Backsulgi samples added with egg yolk powder, raw soybean flour and parched soybean flour were higher in yellowness(b) than the controls. 2. Both swelling power and pore ratio of Backsulgies added with raw soybean flour were higher than those of controls. 3. A cross-sectional observation using an electron microscope indicated that rice flour particles of controls had uneven pores and were conglomerated in a large lump while Backsulgi samples of raw soybean flour or roasted soybean flour had large and even pores and showed loosened bonding to be transformed into a sponge shape. 4. In hardness, Backsulgi samples added with raw soybean flour had less changes in hardness than that of controls, indicating that the effect of retarding retrogradation was higher when the storage time got longer.

• Korean journal of food and cookery science
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• v.18 no.4
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• pp.390-398
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• 2002

The purpose of this study was to select a cake ingredient acting as an emulsifier to retard the retrogradation of rice cake commercially available. For the purpose, Backsulgi, a traditional Korean rice cake, was prepared by adding various ingredients having high contents of lecithin such as raw soybean powder, parched soybean powder, soybean oil, egg yolk powder, and then the changes in the sensory and textural characteristics of the cakes were determined while storing them at the temperatures of 4$\^{C}$ and 20$\^{C}$ for 0, 1, 2 and 3 days. Based on the sensory evaluation, Backsulgi samples added with raw soybean flour were significantly different in roasted nutty smell, roasted nutty taste, softness, moistness, cohesiveness and overall quality compared with the control in the longer storage time at 20$\^{C}$.

• The Plant Pathology Journal
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• v.25 no.3
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• pp.280-285
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• 2009

Powdery and downy mildews caused by Sphaerotheca fusca and Pseudoperonospora cubensis are the most common and serious diseases of cucumber worldwide. In spite of the introduction of highly effective systemic fungicides, control of these diseases remains elusive. Hence, this study aimed to develop an alternative method to chemicals in controlling the diseases by using different types of cooking oil. Egg yolk, which contains a natural emulsifier, lecithin, was selected as a surfactant to emulsify the oils. Among the different cooking oils used, soybean, canola (rape seed), safflower, sunflower, olive, and corn oils showed over 95% control values against powdery mildew of cucumber in a greenhouse test. In particular, 0.3% canola oil emulsified with 0.08% yolk (1 yolk and 60 ml canola in 20 l spray) was found to be the most effective. The treatment resulted in 98.9% and 96.3% control efficacies on powdery and downy mildews, respectively, of cucumber in the field. Canola oil exhibited direct and systemic effect, wherein powdery mildew of cucumber was suppressed only on treated leaves but not on non-treated leaves in a plant, while mycelia and conidia of the pathogen were severely distorted or destroyed by the treatment. The prospect of using the canola oil and yolk mixture as a natural fungicide is highly promising because of its effectiveness, availability, low cost, simple preparation, and safety to humans and the environment. The use of the canola oil and yolk mixture is expected to be an effective fungicide for use in organic farming and home gardening.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.138-142
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• 2001

Solid contents, free sugars, phenlic compounds and glycyrrhizin of extracts obtained from by-products of Glycyrrhizia uralensis by three different methods, i.e., shaking, heating, and static methods, were determined. Solid contents of extracts obtained by shaking, heating and static method were 15.6%, 15.0% and 5.3%, respectively. Phenolic compound contents of them were 11.33 mg/100 mL, 11.21 mg/100mL and 10.15 mg/100 mL. Main free sugars in the extracts from the by-products of G. uralensis were fructose, glucose, sucrose, and maltose. Glycyrrhizin content of the extracts from the by-products of G. uralensis were 2.79%, 3.54% and 0.63%, respectively. Extract obtained by the shaking methods had an ability of donating electron to DPPH. The relative antioxidant effects of th extract obtained from the shaking method showed 70% inhibitory effect of peroxidation on egg yolk lecithin.

• Archives of Pharmacal Research
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• v.10 no.2
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• pp.75-79
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• 1987

Liposomes were studied as a drug delivery system. Multilamellar vesicles, small unilamellar vesicles and large unilamellar vesicles containing cytarabine were prepared using egg yolk lecithin and cholesterol. Large unilamellar vesicles showed the highest encapsulation efficiency of all and their encapsulation efficiency increased as the buffer volume decreased. Cholesterol increased the stability of liposomal drug products as drug carriers and reduced the permeability of drug across the liposomal membrane. The release rate of cytarabine increased with incubation temperature and decreased with cholesterol incorporation in liposomal membrane. The release mechanism of cytarabine from large unilamellar vesicles in vitro was chiefly due to simple diffusion across the liposomal membrane rather than liposomal rupture.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1216-1220
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• 2003

The antioxidative activities of methanol extracts of chestnut flower (Castanea Crenata Flos.) were determinated in vitro using an experimental model system. Solid yield of chestnut flower extracts was 6.26% and total phenolic acid accounted for about 20% of the crude extract. The DPPH radical scavenging activity of methanol extracts prepared from chestnut flower was 17.22%. Although the DPPH radical scavenging activity of chestnut flower extracts was lower than that of other antioxidants, chestnut flower extracts showed continuous activity by time course. The SOD-like activities of methanol extracts prepared from chestnut flower were 65.10%, 95.70% in BHT, 93.29% in quercetin, and 30.30% in ascorbic acid. Chestnut flower extracts showed 51.45% inhibitory effect on peroxidation of egg yolk lecithin.

• Journal of the Korean Society of Food Culture
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• v.18 no.6
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• pp.569-574
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• 2003

This study was conducted to investigate the effect of physical properties and antioxidant activities of the beer made by Lycii fructus for development of functional beer. Physical properties such as $Brix^{\circ}$, pH and hunter values were determined and compared with commercial beer. L(lightness) value was not significant difference among beer, although a(redness) and b(yellowness) values were higher in Lycii fructus beer than those of the commercial beer. Total phenolic acid contents were 0.790 mg/mL in Lycii fructus beer and 0.603 mg/mL in commercial beer. Electron donatin ability was 93% in Lycii fructus beer and 87% in commercial beer. Lycii fructus beer showed higher SOD-liked activities than in the commercial beer. The relative antioxidant effects of the Lycii fructus beer showed 19% inhibitory effect on the peroxidation of egg yolk lecithin.

• BMB Reports
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• v.37 no.4
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• pp.416-421
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• 2004

The antioxidant activities of NADH and of its analogue, 1,4-dihydro-2,6-dimethyl-3,5-dicarbethoxy-pyridine ($PyH_2$), were evaluated in vitro. NADH was found to be oxidized by the peroxyl radical derived from 2,2-azobis-(2-amidinopropane) dihydrochloride (AAPH) decomposition, in a pH-dependent manner. Both NADH and $PyH_2$ inhibited the peroxidation of egg yolk lecithin (EYL) liposomes, although $PyH_2$ was more effective than NADH when 2,2'-azobis-4-methoxy-2,4-dimethyl-valeronitrile (methoxy-AMVN) was employed to induce EYL liposome peroxidation. The antioxidant activities of NADH and $PyH_2$ were also evaluated by measuring their influences on 1,3-diphenylisobenzofuran (DPBF) fluorescence decay in the presence of peroxyl radicals. NADH and $PyH_2$ were much more effective at inhibiting DPBF quenching in Triton X-100 micelles than in liposomes. These results indicate that NADH can inhibit lipid peroxidation despite being hydrophilic. Nevertheless, membrane penetration is an important factor and limits its antioxidant activity.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.134-140
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• 2004

Optimal extraction method for antioxidant compounds from coat of grape dreg was established. Extracts were prepared with ethanol solutions containing phosphoric, formic, acetic, HCl, TFA, and citric acids. Antioxidant compounds of grape coat were determined by HPLC analysis and evaluated for antioxidizing effects using in vitro model system. Peonidin-3-glucoside content was the highest in 0.1% HCl-added ethanol extract. The extract prepared from pure ethanol without organic acids showed the highest content of cyanidin-3-glucoside among samples tested. Resveratrol and quercetin contents, the most important antioxidants, were highest in 0,1% HCl-added extract. Electron-donating ability was high in 0.1% acetic acid-added extract. SOD-like activities were 95.08% and 94.39% in 0.1% formic and 0.1% citric acid extracts, respectively. Inhibitory effects on peroxidation of egg yolk lecithin were observed in phosphoric (60.51%), citric (59,27%), and formic acid (56,77%) extracts. Hydrogen radical-scavenging activity was 59.47% in 0,1% HCl extract. Results suggest addition of 0.1% HCl in ethanol solution affords the highest yield in antioxidant compounds and antioxidant activities.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1098-1102
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• 2002

Antioxidative activities of ethanol extracts of seed, branch, leaves, and aerial part of Crotalaria sessiflora L. were compared using in vitro experimental model. Solid contents of each extracts were 12.68, 16.28, 13.04, and 18.59 g/ 100 mL, and phenolic acid contents were $0.082{\pm}0.003,\;0.099{\pm}0.010,\;0.071{\pm}0.002,\;and\;0.094{\pm}0.011\;mg/mL$ in branch, aerial part, seed, and leaves, respectively. Extracts prepared from leaves showed highest electron-donating ability toward DPPH. SOD-liked activities were 78.95, 70.85, 74.65, and 87.49% in aerial part, branch, seed, an leaves respectively. Extracts prepared from leaves showed 59.39% inhibitory effect on peroxidation of egg yolk lecithin.