• 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.

• Korean Journal of Plant Resources
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• v.34 no.6
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• pp.517-526
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• 2021

Brown rice is more nutritious than the commonly consumed white rice, however, the former is not widely accepted because of its coarse texture and difficulty in cooking. Germination is an easy technique to minimize the drawback of normal brown rice. The objective of this study was to investigate the effect of three different concentrations (1, 3, and 5% w/v) of turmeric extracts on the nutrient and antioxidant activities of germinated brown rice (GBR). The b (yellowness) values of the turmeric-treated GBR were significantly higher than that of the untreated control. Lower concentration (1%) slightly increased (3395.5 mg/kg) but higher concentrations (3 and 5%) reduced (1735.8 - 2393.7 mg/kg) the total mineral content in GBR, as compared to the control (3377.4 mg/kg). The amount of essential, non-essential, and total amino acids, including GABA, were increased with the concentration of turmeric extracts. The amount of essential amino acids was increased by 58.3, 71.5, and 88.3% with the application of 1, 3, and 5% extracts, respectively. The antioxidant potential of GBR was also enhanced with turmeric treatment. Overall results indicated that 1 or 3% turmeric treatment could be appropriate to enhance the nutritional and functional value of GBR.

• Journal of Ecology and Environment
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• v.30 no.4
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• pp.319-324
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• 2007

To investigate the impacts of transgenic rice on freshwater organisms, we conducted two life table experiments using Daphnia magna for fifteen and twenty days, respectively. We examined life history traits such as population growth rates (r), reproductive rates ($R_0$), generation times, and survivorship. In the first experiment, we used non-drought-stressed transgenic and non-transgenic rice harvested in 2005. In the second study, we used non-transgenic and transgenic rice harvested in 2006 following drought stress. Each experiment involved three treatments in which D. magna neonates were fed with Selenastrum capricornutum (control treatment) and S. capricornutum with 5% aqueous extracts of non-transgenic rice (N-T) and transgenic rice (T). In the first experiment, D. magna showed reduced population growth rates and lowered fecundity in the N-T and T treatments. In the second experiment, D. magna receiving both transgenic and non-transgenic rice extracts showed very high mortality, low population growth rates and reproduction rates. We could not detect any significant negative effects of extracts from transgenic rice on D. magna life history traits at 95%.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.178-182
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• 1997

The effect of various rice bran extracts such as water extracts (RBW), methanol extracts (RBM) and protein-fiber extracts (RPDF) on serum and liver lipid contents were investigated in rats fed with high-fat diet for 4 weeks. The increases of body weights in RPDF group were lower than those of control group. Serum total cholesterol concentrations were significantly decreased in RPDF group compared with control group. The contents of liver lipid in all three experimental groups were decreased compared to control group. Especially, total cholesterol contents of liver in RPDF group were significantly lower than those in control group. Compared to control group, the levels of thiobarbituric acid reactive substance in the livers of rats in all experimental groups were significantly reduced, but there was no significant difference among the three experimental groups.

• The Journal of Natural Sciences
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• v.13 no.1
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• pp.65-71
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• 2003

Angiotensive I-converting enzyme inhibitory activity of various extracts from some rice brans were investigated with its optimal extraction conditions. Water extracts of Ilpumbyeo rice bran showed the highest ACE inhibitory activities of 7730%. ACE inhibitor from Ilpumbyeo rice bran was maximally extracted when its powder was treated with 10 times of distilled water for 12h at $30^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.1
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• pp.54-61
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• 2002

The antioxidant activities of methanol extracts of sixteen samples were tested using 1.1-diphenyl-2-picryl hydrazyl(DPPH) reactivity and TBARS substances assay in vitro. The methanol extracts of the rice brans from three wild rice -O. minuta, O. rufipogon, and O. barthii-were found to be the most effective in DPPH radical scavenging activity. The next effective ones were the rice brans of Heugjinjubyeo and leaves of Tapgolbori. When tested on lipid peroxidation using a lipid peroxidation generation system mediated by $H_2O$$_2$/Fe$^{2+}$ in rat liver homogenates, the brans and hull of wild rice (O. minuta, O. rufipogon, and O. barthii) and rice bran of Heugjinjubyeo exhibited protective activities against lipid peroxidation in the order of effectiveness.s.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.6
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• pp.917-923
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• 2013

This study investigated the enzyme inhibitory effects of ethanol extracts from the different parts of rough rice (Oryza sativar L.) from its germination period. Rough rice was germinated at $37^{\circ}C$ for 6 days, then separated into hull+sprout and brown rice. ${\alpha}$-Glucosidase inhibitory activity had the highest value (39.38%) in hull+sprout extracts after 5 days of germination. ${\alpha}$-Amylase and DPP-4 inhibitory activity had the highest values (75.32% and 47.77%, respectively) in hull+sprout extracts after germination for 5 days. ACE inhibitory activity of hull+ sprout extracts increased from 43.16% at the beginning to 58.60% at 5 days, while brown rice extracts increased this activity from 0.88% at the beginning to 14.50% at 4 days. The xanthine oxidase inhibitory activity of hull+ sprout extracts increased from 62.02% at the beginning to 64.49% at one day, and then decreased. Lipase inhibitory activity had its highest value (55.17%) in hull+sprout extracts after germination for 5 days. These results indicate that the optimal germination period for increasing enzyme inhibitory activities may be 5 days, and that hull+sprout extracts have a higher enzyme inhibition activity than brown rice.

• Korean journal of food and cookery science
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• v.19 no.5
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• pp.571-580
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• 2003

The purpose of this study was to assess the optimum coating ratio for rice, using various ratios of mulberry leaves extract, 1.0, 1.5, and 2.0%, and to determine the optimum ratio of added water, in proportion to the total weight of mulberry rice. The moisture content of the soaked rice, and the optimum water uptake rate, moisture content of the cooked rice, as well as its blue and color values, mechanical characteristics, internal structure and sensory evaluation, were analyzed. The statistical data analyses were completed using the SAS program. The results are summarized as follows: The moisture content of mulberry rice was less than that of raw rice. The average optimum water uptake of the soaked mulberry rice at the different water temperatures, 10, 20 and 30, was 20% of the total weight of the raw mulberry rice. As for the results of the sensory evaluation,; 140% water, in proportion to the total weight of raw mulberry rice, was judged to be the optimum. The average moisture content of the cooked mulberry rice was 45∼50%, but there was no significant difference in the various coating ratios. The blue value of the cooked mulberry rice awas highest on the first day of cooking. The L- and a-values decreased with increasing coating ratio, but the b-value increased under the same conditions. As for the mechanical characteristics,; the adhesiveness, hardness and springiness decreased during 2 days of storage. The internal structure of the mulberry rice, observed by SEM, showed a close structure on increasing the coating ratios of mulberry leaves extracts. It was concluded that the optimum coating ratio of mulberry rice and ratio of added water for cooking wereas 1.5 and 140%, respectively, in proportion to the total weight of raw mulberry rice.

• Korean Journal of Food Science and Technology
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• v.50 no.5
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• pp.528-534
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• 2018

The current study investigated the effects of enzyme treatment on black rice (Oryza sativa L.) aleurone layer extracts. Different enzymes (lipase, lecitase ultra and lipopan 50BG) were used to test anti-oxidant and anti-inflammatory activities in vitro. The antioxidant activities of enzyme treated or non-enzyme treated extracts of black rice bran were evaluated via 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity. Lipase treated extracts of black rice bran showed higher antioxidant activity compared to that of non-enzyme treated extracts. Anti-inflammatory activities of enzyme treated black rice bran extracts on nitrite production and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) secretion, were tested using a nitric oxide (NO) colorimetric assay kit and an enzyme-linked immunosorbent assay (ELISA) kit. The ethanolic extract of enzyme treated black rice bran decreased the levels of nitric oxide production and pro-inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$, in a lipopolysaccharidestimulated RAW 264.7 cell culture. These findings indicate that enhanced anti-oxidant and anti-inflammation activities of the ethanolic extracts of enzyme treated black rice (Oryza sativa L.) aleurone layers, may be attributed to molecular conversion of ingredients in enzyme catalyzed reactions.

• The Plant Pathology Journal
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• v.20 no.3
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• pp.184-191
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• 2004

Methanol extracts of fresh materials of 57 plants were screened for in vivo antifungal activity against Magna-porthe grisea, Corticium sasaki, Botrytis cinerea, Phyto-phthora infestans, Puccinia recondita, and Blumeria graminis f. sp. hordei. Among them, seven plant extracts showed disease-control efficacy of more than 90％ against at least one of six plant diseases. None of the plant extracts was highly active against tomato gray mold. The methanol extracts of Chloranthus japonicus (roots) (CjR) and Paulownia coreana (stems) (PcS) displayed the highest antifungal activity; the CjR extract controlled the development of rice blast, rice sheath blight, and wheat leaf rust more than 90％, and tomato gray mold and tomato late blight more than 80％. The PcS extract displayed control values of more than 90 ％ against rice blast, wheat leaf rust, and barley powdery mildew and more than 80％ against tomato gray mold. The extract of PcS also had a curative activity against rice sheath blight and that of CjR had a little curative activity against rice blast. On the other hand, the extract of Rumex acetocella roots reduced specifically the development of barley powdery mildew. Further studies on the characterization of antifungal substances in antifungal plant extracts are underway and their disease-control efficacy should be examined under greenhouse and field conditions.