• Food Engineering Progress
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• v.15 no.4
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• pp.388-397
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• 2011

The purpose of this study was to determine the optimum ethanol extraction conditions for maximum extraction of functional components such as ferulic acid, oryzanol, and toopherol from black rice bran using Response Surface Methodology (RSM). A central composite design was applied to investigate the effects of the independent variables of solvent ratio ($X_{1}$), extraction temperature ($X_{2}$) and extraction time ($X_{3}$) on the dependent variables such as total phenol components ($Y_{1}$), total flavonoids compounds ($Y_{2}$), electron donating ability ($Y_{3}$), $\gamma$-oryzanol ($Y_{4}$), ferulic acid ($Y_{5}$) and $\alpha$-toopherol components ($Y_{6}$). ANOVA results showed that coefficients of determination (R-square) of estimated models for dependent variables ranged from 0.8939 to 0.9470. It was found that solvent ratio and extraction temperature were the main effective factors in this extraction proess. Particularly, the extraction efficiency of ferulic acid, $\gamma$-oryzanol and $\alpha$-toopherol components were significantly affected by extraction temperature. As a result, optimum extraction conditions were 20.35 mL/g of solvent ratio, 79.4$^{\circ}C$ of extraction temperature and 2.88 hr of extraction time. Predicted values at the optimized conditions were acceptable when compared with experimental values.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9517-9522
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• 2014

Purple rice (Oryza sativa L. var. indica) cv. Kum Doisaket is cultivated in northern Thailand. This study evaluated the mutagenic and antimutagenic properties of hydrophilic and lipophilic components of purple rice using the Ames test. The seed and hull of purple rice were extracted with hexane, methanol, ethanol, and water. The methanol extracts had the highest amounts of phenolic acids and flavonoids, while the hexane extracts contained large amount of tocols and ${\gamma}$-oryzanol. None of the extracts were mutagenic in Salmonella typhimurium strains TA98 and TA100. The hexane extract of rice hull and the methanol extract of rice seed were strongly effective against aflatoxin B1- and 2-amino-3, 4 dimethylimidazo (4, 5-f) quinoline-induced mutagenesis, while aqueous extracts showed weakly antimutagenic properties. All extracts with the exception of aqueous extracts enhanced the number of revertant colonies from benzo (a) pyrene induced-mutagenesis. None of the extracts inhibited mutagenesis induced by the direct mutagens 2-(2-furyl)-3-(5-nitro-2-furyl)-acrylamide and sodium azide. The hull extracts showed more potent antimutagenicity than the seed extracts. Based on a chemical analysis, ${\gamma}$-oryzanol and ${\gamma}$-tocotrienol in the hull and cyanidin-3-glucoside and peonidin-3-glucoside in the seed are candidate antimutagens in purple rice. The antimutagenic mechanisms of purple rice might be related to either modulation of mutagen metabolizing enzymes or direct attack on electrophiles. These findings supported the use of Thai purple rice as a cancer chemopreventive agent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.2
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• pp.179-185
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• 2010

To evaluate the antioxidant and antitumor potential of a newly bred rice, Hiami (Suweon-511), total polyphenol content, $\gamma$-oryzanol content, radical scavenging activities, and antitumor activities were measured (control: Ilpum). Total polyphenol contents were 6.31 and 3.75 mg/g for unhulled (UHR) and hulled rice (HR) of Hiami, which was higher than that of Ilpum (5.66 and 3.47 mg/g). The $\gamma$-oryzanol contents were 33.53 and 39.47 mg/100 g for UHR and HR of Hiami, which was higher than that of Ilpum (24.33 and 28.68 mg/100 g). DPPH radical, hydrogen peroxide, superoxide radical and hydroxyl radical scavenging activities of 70% ethanol extracts of Hiami were higher compared to Ilpum, and UHR was higher than those of HR. Antitumor activities of the 70% ethanol extracts of Hiami and Ilpum were increased with a dose-dependent manner. The extracts of Hiami have higher activities of antitumor activities on gastric and breast cancer cell lines compared to other cancer cell lines, and Ilpum has higher activities of antitumor activities on colon and liver cancer cell lines.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.9
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• pp.1265-1270
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• 2011

We evaluated changes in the chemical composition of rough rice (Oryza sativa L.) according to germination period. Rough rice was germinated at $37^{\circ}C$ for 8 days. Crude protein content increased from 71.67 mg/g in raw rough rice to 85.20 mg/g after 8 days of germination. Crude lipid content increased from 2.19% to 3.58% (p<0.05), whereas crude ash was not significantly changed. Phytic acid content decreased from 6.25 mg/g in raw rough rice to 1.54 mg/g after 8 days of germination. Free fatty acid content increased from 0.17% to 0.32% during 8 days of germination. Major fatty acids were palmitic, oleic, and linoleic acids, and total fatty acid content increased up to 95%. Vitamin E and ${\gamma}$-oryzanol contents in raw rough rice were 2.94 mg/100 g and 6.47 mg/g, respectively, increased to 5.55 mg/100 g and 8.16 mg/g after 4 days of germination, and then decreased afterward. These results indicate that the optimum germination period of rough rice for increasing functional components may be 3~4 days.

• Journal of Life Science
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• v.18 no.9
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• pp.1212-1218
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• 2008

The synergistic effect of conjugated linoleic acid (CLA) and $\gamma$-oryzanol (OZ) on the reduction of visceral and body fats was investigated in mice. Female ICR mice, 10 weeks of age, were acclimated for one week and then randomly divided into 5 treatment groups by body weights: Control (70 ${\mu}l$ olive oil + 30 ${\mu}l$ CLA), CLA-OZ 1 (70 ${\mu}l$ olive oil + 30 ${\mu}l$ CLA + OZ 0.5 mg), CLA-OZ 2 (70 ${\mu}l$ olive oil + 30 ${\mu}l$ CLA + OZ 1.0 mg), OZ (100 ${\mu}l$ olive oil + OZ 1.0 mg), and Olive oil (100 ${\mu}l$ olive oil). Samples were daily intubated, p.o., for 4 weeks. Food and water were ad libitum. Four weeks later, mice were sacrificed by neck dislocation, followed by measuring whole body weight, empty carcass weight (ECW), which is weight without organs and visceral fats, visceral fats, body fats and protein content. Mice treated with CLA (control) sample maintained significantly, p<0.05, lower whole body weight, ECW, visceral and body fats, relative to mice treated with olive oil sample, indicating that CLA reduces the visceral and body fats. The CLA-OZ 1 treatment significantly reduced, p<0.05, visceral and body fats as compared to OZ treatment, but not significantly different from control treatment.Meanwhile, CLA-OZ 2-treated mice maintained significantly, p<0.05, lower visceral and body fats than control and OZ-treated mice. Protein contents in mice were not affected by any other treatments. These results suggest that OZ enhanced the reduction of visceral and body fats in mice by CLA.

• Journal of the Korean Society of Food Culture
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• v.38 no.6
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• pp.456-464
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• 2023

The purpose of this study was to investigate nutritional and functional ingredients and antioxidant activity after fermenting rice bran using Lactobacillus brevis for 24, 36, and 48 hours. The results of the analysis of the nutritional ingredients revealed that there was no significant difference in the carbohydrate, crude protein, crude fat and ash content regardless of the fermentation process and fermentation time. The amount of dietary fiber was significantly different between the unfermented and fermented rice bran and was observed to be the highest after a 48-hour fermentation. The γ-oryzanol, gamma-aminobutyric acid (GABA) and total phenolic contents were significantly higher in the fermented rice bran compared to the unfermented rice bran (p<0.05) and the GABA and total phenolic contents increased significantly as the fermentation time increased (p<0.05). The 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), superoxide and hydroxyl radical scavenging activities used to measure antioxidant effects significantly increased as the fermentation time increased (p<0.05). From these results, it was confirmed that the antioxidant effect and functional components, namely γ-oryzanol, GABA, and the total phenolic content of rice bran improved with fermentation. Based on these results, fermented rice bran could be presented as a functional material for use in high value-added industries.

• Bulletin of Food Technology
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• v.12 no.1
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• pp.84-87
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• 1999

식품으로 사용된 미강유는 1994년 이래로 미국에서 상업적으로 생산되어 왔다. 다른 식물성 기름과 비슷한데도 불구하고 미강유가 niche 시장에서 특별한 기름으로 부각된 것은 몇 가지의 독특한 성질 때문이다. 미강유는 견과류와도 같은 향기가 매우 좋고 추출될 때는 튀김유로서 매우 안정적이다. 그러나 미강유의 가장 주목할만한 특징은 $ \gamma-oryzanol과 tocotrienols같은 nutraceutical value가 매우 높은 수준으로 함유되어 있다. 1997년 식물성유의 연간 세계 총생산은 약 8천4백만 톤으로 추정된다(USDA, 1998). 전세계 쌀 수확량으로부터 약 7백만 톤의 쌀겨기름을 생산할 수 있다. 이 양은 연간 총생산 식물성유의 약8%에 해당된다. 그러나 현재 연간 세계 미강유 생산이 80만 톤 미만으로서 모든 식물성유의 약1%로 추정된다 대규모 정미기가 갖추어져야만 실용적인 규모로 미강으로부터 기름을 추출하고 미강의 안정화 시스템 설비를 구비할 수 있다. 그러나 세계 미곡 생산량의 대부분이 소규모 정미기로 가공된다. 이러한 이유 때문에 가까운 장래에 전체 미강 생산의 50%이상으로부터 미강유를 생산할수 있을 것 같지는 않다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.4
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• pp.470-478
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• 2009

Low trans fats were synthesized by interesterification of rice bran oil (RBO), palm stearin (PS) and high oleic sunflower seed oil (HO) using TLIM from Thermomyces lanuginosa. After 24-h reaction, physicochemical characteristics such as fatty acid and triacylglycerol composition, solid fat content, melting point, tocopherol, oryzanol and phytosterol contents were evaluated. Trans fatty acid contents of the produced low-trans fats showed less than 0.5 wt%. Mostly, triacylglycerol species in the products were palmitoyl-linoleoyl-oleoyl-glycerol (PLO), palmitoyl-oleoyl-oleoyl-glycerol (POO) and palmitoyl-oleoyl-palmitoyl-glycerol (POP). Total tocopherol contents ranged from 6.94 to 11.83 mg/100 g while $0.18{\sim}0.49$ mg/100 g of $\gamma$-oryzanol and $182.47{\sim}269.08$ mg/100 g of phytosterols were observed depending on the substrates ratios. When the content of PS in the reaction substrate was increased, solid fat content and slip melting points were increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.815-819
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• 2008

The colored rice, particularly black rice, has been well characterized to possess antioxidant properties. Rice bran, a by-product of the rice milling process, contains high levels of several phytochemicals which have antioxidant activities as well as health-beneficial properties. The purposes of this study were to evaluate the antioxidant compounds and antioxidant activities of the methanolic extracts from milling fractions and whole grain of two black rice cultivars. Whole black rice of the two cultivars were milled into rice bran and endosperm using the gradual milling system. These were evaluated for antioxidative activities by DPPH and ABTS radical scavenging activities. To determine the antioxidant compounds in the methanolic extract from the milling fractions, the content of polyphenolics, flavonoids, anthocycanins and ${\gamma}$-oryzanol were measured by spectrophotometric methods and vitamin E analysis was carried out by HPLC. The yield of whole black rice, rice bran, and endosperm were 3.1, 15.3, and 0.9% for Heugjinjubyeo and 2.7, 15.5, and 1.1% for Heugkwangbyeo, respectively. The methanolic extracts from rice bran showed generally higher antioxidant activities than the extracts from whole grain and endosperm. In addition, antioxidant compounds distributed much higher contents in rice bran extract than in the extracts from whole grain and endosperm. A significant correlation was also noted between free radical scavenging activity and polyphenolic compounds. The results of this study show that notable antioxidant activity in black rice bran are considered to have significant health benefits.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.6
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• pp.781-789
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• 2011

We studied the biological activities, including antioxidant compounds, antioxidant activities, anti-proliferative activities, and immunological activities of brown rice and germinated brown rice. We examined the DPPH, ABTS radical scavenging activity, and reducing power of 70% ethanol extracts from some cultivars of brown rice and germinated brown rice. The total polyphenol, total flavonoid, and ${\gamma}$-oryzanol contents of the extracts were measured with spectrophotometric methods. The Hongjinjubeyo brown rice and germinated brown rice extracts showed markedly higher antioxidative activity than those of 70% ethanol extracts from other cultivars. The 70% ethanol extracts from brown rice and germinated brown rice had the most effective anti-proliferative activity (cytotoxicity) against breast cancer cells (MCF-7) compared to colorectal cancer cells (HCT-116). A $500\;{\mu}g$/mL concentration of 70% Hongjinjubyeo ethanol extract had higher macrophage and mitogenic activities of immunological activity than other cultivars.