• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.11
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• pp.1691-1695
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• 2016

The objective of this study was to determine the antioxidant activities of rice bran extracts by three different extraction methods. Rice bran was extracted by solvent extraction, saponification extraction, and supercritical fluid extraction. The antioxidant activities of the rice bran extracts were determined based on ABTS and DPPH radical scavenging activities, reducing power, and lipid peroxidation inhibitory activity. The unsaponifiable matter (USM) extracted by the saponification method showed higher ABTS (671.7 mg Trolox equivalent antioxidant capacity (TEAC)/g) and DPPH (330.7 mg TEAC/g) radical scavenging activities as well as reducing power ($A_{700}=1.14$) than those of the solvent extract (ME) and supercritical fluid extract (SFE). Inhibitory effect on lipid peroxidation was higher in USM (68.7%) and SFE (75.4%) compared to ME (47.8%). USM indicated relatively higher antioxidant activities compared with those of SFE and ME. These results show that the saponification method for extraction of USM from rice bran extracted was the most effective method for enhancement of antioxidant activity. In addition, these extracts from rice bran could be used as functional ingredients in the food industry.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.438-444
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• 1999

The natural full-fat rice bran is reported to contain 8.4 to 14.7 wt % Lipids, but the amount and composition of bran depend on the type of rice, quality of paddy, pretreatments to paddy such as parboiling, type of milling system employed, and the degree of polishing. These lipids are usually mixtures of several class fatty acids containing palmitic acid, linolenic acid, linoleic acid, oleic acid, stearic acid, tocopherol, squalene, etc. In this study the oil rich essential fatty acid (EFA) including squalene was extracted from the domestic brown rice bran using supercritical fluid extraction (SFE) and cosolvent induced SFE process, respectively. And the extracts were analyzed with GC-MSD. The extracted amount of rice bran oil was dependent upon the operating pressure and temperature, and the fatty acid composition of oil was varied with the reduced density (${\rho}_{\gamma}$) of supercritical carbon dioxide. About 70~80% of rice bran oil was extracted in 4hrs. The cosolvent induced SFE process shortened the total extraction time, extracted greater amount of oil than SFE process. Especially squalene which was not found in solvent extract phase was identified in SFE and cosolvent induced SFE process.

• Journal of Life Science
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• v.23 no.8
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• pp.1010-1018
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• 2013

The greenhouse whitefly, Bemisia tabaci, is considered one of the most destructive pests of crops. In this study, we aimed to determine the optimal liquid culture conditions in shake flasks for maximal sporulation of Beauveria bassiana M130 using rice bran. The optimal initial pH for the spore production of B. bassiana using extracted rice bran medium was 5.2 and $28^{\circ}C$. The screening in shake flasks of carbon and nitrogen sources resulted in the identification of an optimal medium based on 0.5% $(NH_4)_2SO_4$, with extracted rice bran 8:1. Using this medium, a production level of $2.15{\times}10^9$ spores per ml was obtained after six days from culture inoculation at $28^{\circ}C$ in a rotary shaking incubator at 130 rpm. In addition, the specific activities of extracellular enzymes of chitinase and protease were $4,296{\mu}mol$ and $375{\mu}mol$, respectively. These results suggest that Beauveria bassiana M130 could be a bio-controller for the greenhouse whitefly.

• Current Research on Agriculture and Life Sciences
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• v.27
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• pp.13-19
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• 2009

The purpose of this study was the efficient use of the black rice bran for dyeing textiles. For this purpose, we investigated proper extracting conditions of black rice bran, dyeability and dyeing fastness of dyed silk fabrics. To find proper extracting condition of black rice bran, we extracted black rice bran with water at different temperatures($40^{\circ}C$, $60^{\circ}C$, $80^{\circ}C$), different extracting pH(pH3, pH4, pH5, pH6) and extracting time(20, 40, 60, 80, 100, 120, 140, 160, 180min.). Also we investigated the effect of dyeing time(1, 2, 3, 4, 5, 6hr.), dyeing temperature($40^{\circ}C$, $60^{\circ}C$, $80^{\circ}C$) and mordanting method(non, pre, sim, post) to examine dyeability and dyeing fastness of dyed silk fabrics. As a result, when the extracting temperature and time were $80^{\circ}C$, 3hr., respectively, extracting was best. And the higher the extracting concentration, the more the extracting amount. As the dyeing temperature and time were higher and longer, the dyeability of silk fabrics was better. With mordant, the dyeability was improved and when using premordant method better, the K/S value was maximized. The laundering fastness of the silk fabrics dyed with black rice bran was estimated to have a good grade of 3~4, however, the light fastness was poor to have a grade of 1~2.

• Food Science and Preservation
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• v.8 no.3
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• pp.296-301
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• 2001

Physiological functionalities in various extracts of Heugjinju rice bran were determined and its optimal extraction condition were also investigated Angiotensin-converting enzyme(ACE) inhibitory activity, fibrinolytic activity and tyrosinase inhibitory activity were higher in water extracts than those of 80% ethanol and methanol, hexane. Electron donating abilities were 97.8% in hexane extract and 83% in water extracts. ACE inhibitor was maximally extracted from Heugjinju rice bran when it was treated with 20 times of distilled water for 12 h at 20 $\^{C}$. Fibrinolytic compound was also maximally extracted by treatment of 10 times of distilled water for 18 h at 20 $\^{C}$. Electron donating compound and tyrosinase inhibitor were maximally extracted by treatment of 20 times of hexane and 10 times of distilled water at 20 $\^{C}$ for 18 h, respectively

• Journal of Nutrition and Health
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• v.14 no.3
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• pp.146-150
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• 1981

Some enzymatic properties of the lipase extracted from rice bran were studied. The rate of free fatty acid formation as a function of incubation time was maximum after 30 min. at $35^{\circ}C$. The activation energy of the enzyme was 1.83 Kcal/mol and using a olive oil emulsion as substrate, the Km value was $0.8{\times}10^{-3}M$. The enzyme activity was more stimulated by calcium ion. Application of these enzymatic properties onto the effective utilization of rice bran and preservation of rice were discussed.

• Korean Journal of Food Science and Technology
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• v.9 no.4
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• pp.277-283
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• 1977

1) Higher yield of red color was observed by the isolated strain (Monascus D-7) than the type cultures in steamed rice medium. 2) In a case of Monascus purbigerus IAM 8004, best yield of color was obtained at Lin's submerged culture medium containing 1% wheat bran, 2% starch and 3% corn meal instead of rice powder as carbon source. However, in a case of isolated strain (M. D-7), good result was shown at 1% rice bran and 2% starch as a source of carbon in Lin's medium. 3) Good yields were obtained from both strains in Nishikawa's medium which was added with 3% defatted soybean flour. 4) There were no significant differences in pigment extractability among solvents. Extracted pigment was stable in wide range of pH and heat, whereas relatively unstable in sunlight. 5) Toxicological study of extracted pigment determined $LD_{50}$ at 0.2539g/20g, when injected in mouse. When injected in to mouse in 25% ethanol solution: considering the toxicity of ethanol, the toxicity of pigment itself is believed to be none.

• The Korean Journal of Food And Nutrition
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• v.22 no.3
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• pp.456-462
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• 2009

Adlay, barley and rice bran were extracted using various concentrations of methanol(10% and 80%) and chloroform : methanol(2 : 1) to examine the biological activities of these raw grains. Extraction with 80% methanol resulted in high Vitamin C Equivalent Antioxidant Capacity(VCEAC), in the order of barley > rice bran > adlay, as determined by DPPH and ABTS assays. In addition, the extracts of adlay and rice bran showed high cellular antioxidant activity in HepG2 cells possibly due to the presence of polyphenol glycosides in these grains. We examined the expression of glucose/fatty acid metabolizing genes in differentiated 3T3-L1 adipocyte cells. Glut1 was downregulated after treatment with rice bran and no changes in the expression of Glut4 was observed. In contrast, genes involved in fatty acid metabolism, CD36 and aP2, were upregulated. Since these physiological changes were matched with peroxisome proliferator activating receptor $\gamma$(PPAR $\gamma$) agonism, we suggest that the extracts from adlay, barley and rice bran may play preventive roles against aging and diabetes via antioxidant activity and increased uptake of fatty acids by adipocytes.

• Food Science and Preservation
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• v.10 no.3
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• pp.370-375
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• 2003

To obtain the oil sesame, walnut, whole wheat, and rice bran were extracted for 1, 3, or 6 hr by a shanking water bath(35$^{\circ}C$ and 100 rpm), and by soxhlet extractor(80$^{\circ}C$) for 1, 3 or 6 hr, respectively. The highest yield of extracted oil was obtained from the walnut(63.07％ weight) and the whole wheat showed the lowest extraction yield of oil(1.13％ weight). Major fatty acids from the extracted oils were linoleic, oleic, and palmitic acid. The maximum contents of total phytosterol in sesame, walnut, whole wheat, and rice bran were 0.44, 1.57, 2.25, and 2.03(％ weight), respectively. Besides, total tocopherol contents in sesame, walnut, whole wheat, and rice bran were maxima 3.42, 0.16, 2.92, and 0.07(％ weight), respectively. From the extracted oils, structured lipids(SL) were synthesized by the interesterification reaction with conjugated linoleic acid(CLA) in a shanking water bath at 55$^{\circ}C$. When the reactions(1:3 substrate molar ratio, extracted oil:CLA) were conducted for 24 hr, maxima 23.75 mol％ of CLA incorporation was obtained from walnut oil and, in other cases, 16.28 - 19.15 mol％ of CLA was found in the produced SL triacylglycerol molecules.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.77-81
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• 1998

Rice germ oils were extracted from common and dried rice germ $(80^{\circ}C,\;6\;hr)$, and their oxidative stabilities were evaluated by measuring acid value, peroxide value and fatty acid composition during storage at $40^{\circ}C\;and\;60^{\circ}C$. The acid values of all lipids were slightly changed during storage, but peroxide values (POV) were greatly dependent on storage temperature. The POVs of the dried germ oil and the refined rice bran oil were 146.2 meq/kg and 15.1 meq/kg, respectively after 31 days storage at $40^{\circ}C$. However after 24 days of storage at $60^{\circ}C$, the POVs of the dried germ oil and the refined rice bran oil were 151.7 meq/kg oil and 219.6 meq/kg oil, respectively. Major fatty acids were linoleic (39.8%) and oleic acid (34.7%) in rice germ oil, and oleic (40.1%) and linoleic acid (38.1%) in rice bran oil. The major fatty acid compositions were not greatly influenced by drying and storage temperature but linoleic acid decreased about half during storage.