• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.360-365
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• 1996

To investigate the presence of brassinosteroids in rice bran and pㅐlished rice, they were extracted with MeOH. The extracts were purified through sequential procedure of solvent fractionation, silica gel adsorption chromatography, Sephadex LH-20 column chromatography and charcoal adsorption chromatography. The activity of brassinosteroids was monitored by the rice inclination test and its presence was confirmed in each purification step. The purified active components were further separated by TLC and HPLC. Brassinosteroids in active fractions of rice bran were identified as castasterone and teasterone by HPLC. We acknowledge that our work is probably the first report of brassinosteroids in mature seeds of rice The more amount of brassinosteroids was confirmed in rice bran than polished rice. The contents of castasterone and teasterone which were identified in rice bran were 0.15 ng/g and 0.37 ng/g, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1148-1157
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• 2014

Rice bran (RB), a by-product obtained during polishing of un-milled rice, contains a large quantity of essential nutrients such as minerals, vitamins, fiber, amino acids, and antioxidants. In this study, the anti-obesity effects of stabilized RB addition as a food material in a diet-induced obese animal model were investigated. For the analysis, a total of 32 mice were randomly divided into four groups: normal diet group (ND, n=8), high-fat diet group (HFD, n=8), 20% RB added high fat diet group (HFRB20, n=8), and 40% RB added high fat diet group (HFRB40, n=8). The animals were sacrificed after 7 weeks. Body weight gain, various adipose tissue weights, blood glucose concentration, and serum leptin level of the HFRB40 group were found to be significantly lower than those of the HFD group. Moreover, antioxidant enzyme activity of the HFRB40 group was significantly higher than that of the HFD group. However, the HFRB20 group did not show significantly different values. The results of this study show that RB (40%) addition reduces body weight gain and improves obesity-related parameters. These results suggest RB could be considered as a functional additive material for the manufacture of anti-obesity products, and 40% RB addition would be the physiologically effective level.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.590-595
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• 1990

The destructive effect of peroxidized lipid on the amino acid in protein isolate and the proteolytic activity of protease were studied in the model system of rice bran. The content of amino acids in the protein isolate decreased significantly when they reacted with peroxidized lipid (pov. 1200 meq/kg). Most of amino acids were lost by more than 90% in salt soluble protein isolates when analyzed by the method of enzyme hydrolysis. Formaldehyde reduced the activity most severely among peroxidized products. Formic acid, peroxidized lipid and hydroperoxide were also found to reduce the protease activity. The damaging effect of the secondary products on the protease activity was more serious than that of the primary products of lipid peroxidation. The destruction of amino acids in the total protein and Inhibition of protease activity by the peroxidized lipid were apparent.

• Food Engineering Progress
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• v.15 no.2
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• pp.175-181
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• 2011

By using supercritical carbon dioxide fluid, an attempt was made to extract surface-active substances from defatted rice bran. Extraction was carried out according to D-optimal design and results were analyzed by response surface methodology to establish optimum condition. It was found that pressure, temperature and co-solvent (ethanol) influenced in a different extent on the extraction efficiency (i.e., yield and interfacial tension) of surface-active substances. Among them, co-solvent was found to be a major influencing factor, where maximum yield (2.62%) was observed at the highest content (250 g). In addition, it also affected most on the interfacial tension at the oil-water interface but in this case the lowest interfacial tension value (9.51 mN/m) was found when added lowest (50 g). In conclusion, it was estimated that the optimum extraction condition was to be pressure 350bar, temperature $62^{\circ}C$ and co-solvent content 50 g in this study, where extraction yield was 0.69% and interfacial tension to be 10.1 mN/m.

• Food Engineering Progress
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• v.15 no.3
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• pp.276-281
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• 2011

The optimum condition for the extraction and purification processes of phytic acid from defatted rice bran was examined. The phytic acid was efficiently extracted when the defatted rice bran was treated with 10 volumes of 0.5% HCl for 1 hr. For the neutralization of acid-treated extract, 0.5% NaOH was the most acceptable. To purify phytic acid, Diaion HP20 resin was used to remove impurities from the extract. The flow-through was then loaded onto ion exchange columns packed with various resins and among them, Amberlite IRA-416 resin showed highest recovery yield. When the phytic acid was absorbed onto Amberlite IRA-416 resin and then eluted with 0.5% NaOH, 89% of applied phytic acid was eluted. Most proteins were removed from the purified phytic acid and total protein content of the phytic acid was 0.14%(w/w).

• Korean Journal of Food Science and Technology
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• v.48 no.3
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• pp.214-222
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• 2016

This study was performed to increase the production of ${\gamma}$-aminobutyric acid (GABA) by lactic acid bacteria (Lactobacillus brevis CFM11) and manufacture an optimum medium using the sap from Darae (Actinidia arguta). The concentration of GABA in the fermented sap was determined using GABase enzymatic assay. The isolated L. brevis CFM11 produced $605.67{\mu}g/mL$ GABA after incubation for 24 hours at $37^{\circ}C$ in broth. The sap was fermented by L. brevis CFM11 under optimum conditions of $32^{\circ}C$ for 48 hours with 40% rice bran extract, 1.0% sucrose, 3.0% soytone, 0.2% magnesium sulfate, and 0.2% MSG. The fermented sap produced a concentration of $1366.13{\mu}g/mL$ GABA. These results demonstrate that fermenting Darae sap using L. brevis CFM11 can produce a fermented sap beverage with increased GABA content.

• 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.

• Journal of Life Science
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• v.22 no.6
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• pp.828-836
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• 2012

The objective of the current study was to determine the effects of the extracts isolated from the fruit body of Flammulina velutipes cultivated with oriental herbal plants on mouse splenocytes, B cells, and macrophages in vitro. The ethanol extracts B (EEB) directly induced the proliferation of spleen cells in a dose-dependent manner and increased IL-6, TNF-${\alpha}$, and IFN-${\gamma}$ synthesis. The EEB also increased the proliferation of B cells in a dose-dependent manner. The production of immunoglobulin M, G1, G2a, G2b, and IgG3 in the presence of the EEB increased progressively in the culture supernatant. When the EEB were used in macrophage cell line (RAW264.7) stimulation, there was a marked induction of NO synthesis in a dose-dependent manner and an increased IL-6, TNF-${\alpha}$, and GM-CSF synthesis. Intraperitoneal injection with EBB showed life prolongation effect of 16.1% in mice previously inoculated with sarcoma-180, respectively. These results suggest that the capacity of the EEB isolated from the fruit body of Flammulina velutipes cultivated with oriental herbal plants seems to act as a potent immunomodulator causing augmentation of immune cell activity, and with the absence of notable side-effects, Flammulina velutipes EEB could be used as a biological response modifier having possible therapeutic effects against immunological disorders. This study also showed that functional components of Flammulina velutipes were possibly improved by incorporating oriental herbal plants in a growth medium.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.8
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• pp.979-985
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• 2017

This study was carried out to investigate the production of ${\gamma}$-aminobutyric acid (GABA) by lactic acid bacteria and to manufacture GABA using rice bran extract-based optimum medium. Electrostatic spraying technology was used to add GABA into the cereals. The isolated Lactobacillus brevis CFM11 produced the highest GABA production up to a concentration of $2,002.93{\mu}g/mL$ when cultivated in MRS broth containing 0.8% monosodium glutamate (MSG). The production level of GABA was $585.80{\mu}g/mL$ in rice bran extract containing 0.4% MSG, 2% sucrose, 1% skim milk, and 0.2% magnesium sulfate. After electrostatic spraying of the cultured suspension onto rice, GABA concentration reached $228.10{\mu}g/g$ while untreated rice reached $32.23{\mu}g/g$. These results demonstrate that rice bran extract can be an economic commercial medium for GABA production as a substitute for MRS broth. This study demonstrates the novel application of electrostatic spraying of GABA into cereal products for the first time.

• The Korean Journal of Food And Nutrition
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• v.26 no.1
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• pp.1-7
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• 2013

This study was conducted to determine antioxidant compounds and antioxidant activities of rice bran at temperatures of $10^{\circ}C$, $25^{\circ}C$, and $60^{\circ}C$ using 70% ethanol solution. DPPH, ABTS radical scavenging activities and reducing power have been used to investigate the relative antioxidant activities of extracts. The contents of total polyphenol and total flavonoids in the 70% ethanol extracts were measured by spectrophotometer. The total polyphenol content in the rice bran extracts were 790.39~930.07, 782.71~1,039.57, and 848.22~1,052.96 mg gallic acid eq./100 g in $10^{\circ}C$, $25^{\circ}C$ and $60^{\circ}C$, respectively. Antioxidant activities, such as DPPH, ABTS radical scavenging activity and reducing power, in all cultivars and temperatures was the highest in Cheonghaejinmi rice bran extracted at $25^{\circ}C$. The results obtained in the in vitro models suggest that extracts from rice bran, especially Cheonghaejinmi, has significant health-promoting effects, as it exhibits antioxidant activities.