• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2002.08a
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• pp.64-71
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• 2002

Rice(Oryza stiva L.) is a major cereal food providing nourishment to over half of the world's populations and was considered only as a source of energy. However, The recent many researches have been made to suggest that rice may relate to prevention chronic disease and health-promoting properties such as postprandial glucose response, hypocholesterolemic effect and blood pressure-lowering effect. There has been numerous observation supporting that rice has hypocholesterolemic effect. Rice, rice bran, rice bran oil and unsaponifiable matter of rice bran oil reduced plasma cholesterol in rat, hamster as well as human. Components of rice showing hypocholesterolemic effect include dietary fiber(hemicellulose, phytic acid). protein, ${\gamma}$-oryzanol, $\beta$-sitosterol, and tocotrienols. Crapo et al has been studied that the effect of various of starchy foods on the postprandial blood glucose and insulin responses in healthy and diabetic humans. The results showed that rice had lower blood glucose and insulin responses compared to potato, bread and dextrose. The different physical forms in the same starch also produce the different postprandial glucose and insulin responses. In recent years, several studies have shown that some components of rice have potent antioxidant activity against Fe$^{2+}$ -ascorbate induced lipid peroxidation in rat liver microsomal membranes. Cell culture and animal studies have shown that some components of rice have inhibitory effect on the growth and proliferation of several types of human cancer cell. It was also reported that the methanol extract of brown rice has antimutagenic activity against various mutagens. In addition, the pepsine hydrolysate from rice protein is reported to inhibit angiotensin converting enzyme activity. GABA (${\gamma}$ - aminobutyric acid) and GABA enriched rice germ is also effective for lowering blood pressure and triglyceride levels.s.

• Preventive Nutrition and Food Science
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• v.9 no.4
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• pp.330-335
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• 2004

Changes in functional constituents of rice germ prepared using three different heat pretreatments: roasting, steaming and microwave heating, were determined and compared with those of non-treated rice germ. The yield of rice germ oil increased generally and then decreased with increasing time for all three heat pretreatments, although the yields of rice germ oil varied among the three heat pretreatments. There were no major differences in fatty acid compositions among the rice germ oils subjected to the three different heat pretreatments. Levels of $\alpha$-tocopherol in rice germ oil increased up to about 1.5 times at 3 min of roasting and microwave heating, compared to control, and then decreased with increasing treatment time, but $\alpha$­tocopherol concentrations in rice germ oil gradually decreased with increasing steaming time. The contents of three phytosterols ($\beta$-sitosterol, stigmasterol and ergosterol) decreased progressively with increases in roasting and steaming time, while concentrations of the three phytosterols increased up to - 15$\%$ with 3 min of microwave process as compared to control, and then decreased thereafter. Levels of $\gamma$-oryzanol in rice germ oil decreased gradually with increasing time during all three different heat pretreatments. However, levels of $\gamma$ -aminobutyric acid (GABA) in rice germ decreased gradually with increasing roasting time, while those of GABA increased greatly up to about 2 times after 10 min of steaming process, and then decreased slowly thereafter. During microwave heating, the contents of GABA increased at 3 min of treatment time and then decreased. These results suggest that microwave heating may be the most suitable processing method to preserve functional constituents in rice germ.

• Journal of Life Science
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• v.29 no.6
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• pp.671-678
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• 2019

Antibacterial and antioxidant activities of plant sources have attracted a wide range of interest across the world over the last decade. This is due to the growing concern for safe and alternative sources of antibacterial and antioxidant agents. In this study, we focused on the antibacterial and antioxidant activities and the chemical composition of a methanol extract from Viburnum sargentii seeds. The chemical composition was determined by gas chromatography-mass spectroscopy (GC-MS), and the antibacterial activity was screened by a disc diffusion assay. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using the microbroth dilution and spread plate method, respectively. The V. sargentii extract showed growth inhibition activity on all tested Gram-positive (Listeria monocytogenes, Staphylococcus aureus, and Staphylococcus saprophyticus) and Gram-negative (Escherichia coli, Pseudomonas putida, and Proteus vulgaris) pathogenic bacteria. The MIC and MBC ranged from 0.156~1.25 mg/ml for Gram-positive and 0.625~5.0 mg/ml for Gram-negative tested bacteria. The GC-MS results revealed the presence of several phytochemicals such as ${\beta}-sitosterol$ and vitamin E, which are known for their pharmacological applications. The antioxidant activities of V. sargentii extract were investigated by three different methods: the 2,2-diphenyl-1-picrylhydrazyl free radical scavenging assay, the reducing power assay, and the total antioxidant capacity assay. The results showed a concentration-dependent antioxidant potential for all three used methods. In sum, our findings suggest that the methanol extract of V. sargentii seeds has the potential to inhibit the growth of pathogenic bacteria and provide antioxidant compounds, making it therefore worthy of further investigation.

• Korean Journal of Food Science and Technology
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• v.10 no.2
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• pp.181-188
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• 1978

To study on the changes in saponins from callus mass by tissue culture, the callus was derived from the petiole of Korean Ginseng (Panax Ginseng C.A. Meyer) and cultivated on Murashige and Skoog's agar medium supplemented with 2.4-dichlorophenoxyacetic acid and kinetin for 8 months. Then, well-grown callus was analyzed for its components estimation. The results obtained are as follows: (1) When saponins isolated from callus mass were chromatographed on a silca gel plate, and determined by the thinchrograph TFG-10, the ratio of Rb, c to Rg(f) in saponins was 2.16 to 1 and Rb, c, d to Re, g (f) was 1 to 1.63, while in the case of saponins from the root of Panax Ginseng grown by soil culture, the ratio of Rb, c to Rg(f) was 1.03 to 1 and the ratio of Rb, c,d to Re, g(f) was 1 to 1.17. (2) Sapogenins were obtained from the hydrolysates of saponins, and determined by thinchrograph TFG-10. The ratio of panaxadiol to panaxatriol in sapogenins from callus saponins was 2.66 to 1, while the ratio of panaxadiol to panaxatriol in sapogenins from ginseng root saponins was 1.86 to 1. From the results above mentioned, we concluded that the relative contents of sapogenins in saponins from callus mass by tissue culture were different from those in saponins from ginseng root by soil culture.

• Food Science and Preservation
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• v.24 no.3
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• pp.334-342
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• 2017

The content of bioactive substances and antioxidative activity in conventionally grown brown rice (CGBR) and organically grown brown rice (OGBR) were compared. Minerals (mg/100 g) such as magnesium (OGBR, $168.59{\pm}2.62$; CGBR, $121.43{\pm}2.22$), copper (OGBR, $0.50{\pm}0.06$; CGBR, $0.41{\pm}0.05$), and manganese (OGBR, $4.70{\pm}0.04$; CGBR, $2.49{\pm}0.02$) were higher in OGBR than in CGBR (p<0.05). In addition, levels of (${\mu}g/100g$) vitamins B2 (OGBR, $27.22{\pm}2.56$; CGBR, $22.12{\pm}2.24$) and B6 (OGBR, $46.32{\pm}2.66$; CGBR, $39.91{\pm}3.32$) were higher in OGBR than in CGBR (p<0.05). The contents (mg/100 g) of ${\beta}$-sitosterol (OGBR, $27.40{\pm}2.79$; CGBR, $24.75{\pm}1.06$), total phenolic (OGBR, $6.72{\pm}0.02$; CGBR, $6.64{\pm}0.02$), and ferulic acid (OGBR, $1.75{\pm}0.45$; CGBR, $1.11{\pm}0.14$) as well as the antioxidative activity (OGBR, $53.09{\pm}1.90%$; CGBR, $48.29{\pm}3.38%$) evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assay were higher in OGBR than in CGBR, although no significant differences between samples were observed. In comparison to the control group, brown rice samples significantly inhibited cholesteryl ester hydroperoxide formation in rat plasma subjected to copper ion-induced lipid peroxidation. The inhibitory effect of OGBR was higher than that of CGBR. These results indicate that OGBR showed higher levels of bioactive substances and enhanced antioxidative activity than CGBR, although the differences were not statistically significant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1747-1752
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• 2012

This study investigated the physiochemical characteristics of Xanthoceras sorbifolia seed oil. Xanthoceras sorbifolia seed oil was extracted by supercritical fluid extraction (420 atm, $50^{\circ}C$), hexane extraction and heat-pressed extraction ($160^{\circ}C$, $180^{\circ}C$). Acid values and peroxide values were evaluated, as well as the degree of lipid oxidation. The heat-pressed ($160^{\circ}C$) extraction gave a $53.5{\pm}2.5%$ higher yield of oil, compared with the other extraction methods. The acid values from the super critical fluid extraction were the highest, while peroxide values were highest from the heat-pressed extraction at $160^{\circ}C$ (3.10 meq/kg). The contents of linolenic acid and oleic acid were 38.63~41.13% and 26.29~26.85%, respectively. Contents of stigmasterol and ${\beta}$-sitosterol were 6.01~6.49 mg/100 g and 58.19~59.85 mg/100 g, respectively. These results indicate that Xanthoceras sorbifolia seed oil can possibly serve as new edible oils.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1156-1164
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• 2010

Structured lipids (SLs) were synthesized by enzymatic interesterification with evening primrose oil (EPO) and rice bran oil (RBO) in a batch-type reactor. The interesterification was performed using a water shaker for 24 hr at $55^{\circ}C$. Mixing speed was set at 200 rpm and Lipozyme RM IM (immobilized lipase from Rhizomucor miehei, 10% by weight of total substrates) was used as a biocatalyst. Rice bran oil and evening primrose oil were interesterified with various molar ratios (RBO : EPO, 1:3, 1:4, and 1:5 mol/mol). Reversed-phase high performance liquid chromatography connected with evaporative light-scattering detector was performed to separate the triacylglycerol (TAG) species of SLs. In the fatty acid analysis, $\gamma$-linolenic acid (7.9 mol%), linoleic acid (67.3 mol%) and oleic acid (13.2 mol%) were the most abundant fatty acids in the SLs. During 24 hr reaction, most of the reaction occurred within 3 hr. TAG compositions, tocopherols and phytosterols were also analyzed. In the TAG species analysis, LLL (ECN=42, L=linoleic acid) dramatically decreased when the reaction time increased.

• The Korean Journal of Food And Nutrition
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• v.27 no.3
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• pp.339-347
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• 2014

This study investigated the classification of olive oils that are mainly distributed in Korea via imports. The fatty acid contents, degree of color, pigments, anti-oxidants, and sterol contents are analyzed on the different types of olive oil as follows: 10 kinds of extra virgin olive oil, 5 kinds of pure olive oil, and 5 kinds of refined olive-pomace oil. As a result of fatty acid analysis, the majority of oleic acid ($C_{18:1}$) and palmitic acid ($C_{16:0}$), and minority of linoleic acid ($C_{18:2}$) and stearic acid ($C_{18:0}$) were detected without any significant differences between the grades of olive oils. The UV spectrum is related to the ${\Delta}K$, and it is a part of the analysis factor for the purity and degree of degradation of the oil. Extra virgin olive oil had ${\Delta}K$ of almost 0, pure olive oil had 0.07~0.12, and refined olive-pomace oil had 0.1~0.13. These differed from extra virgin oil, and the pure or pomace oil ${\Delta}K$ had a confirmed distinct difference. The color degrees of chlorophyll with a low $L^*$ value and $(-)a^*$ (green) and carotenoid with $(+)b^*$ (yellow) were confirmed to have correlation between extra virgin and other olive oils. To compare chlorophyll and carotenoid as natural pigment in olive oils, 417 nm and the ratio of the absorbance at 480 nm (417/480) was calculated at 1.62 of extra virgin, 1.85 of pure olive oil, and 3.32 of refined olive-pomace oil. Therefore, it will be possible to distinguish when the extra virgin or pure olive oil are mixed with olive-pomace oil. The total amount of tocopherol, an anti-oxidant, were 19.06 in extra virgin, 10.91 in pure olive oil, and 27.88 in refined olive-pomace oil. The high content of tocopherol in pomace oil caused recovery of solvent extraction from olive pulp. Thus, extra virgin oil and pure olive oil were distinguished by olive-pomace oil. Polyphenol compounds in extra virgin olive oil measured high only in ferulic acid with 0.543 mg/kg, caffeic acid with 0.393 mg/kg, and other vanillic acid, vanillin, and p-coumaric acid had similar amount of 0.3 mg/kg. All grade of olive oils had the highest ${\beta}$-sitosterol content. Af (Authenticity factor) value were estimated with campesterol and stigmasterol content ratio (%). Af value was 19.2 in extra virgin olive oil, 17.1 in pure olive oil, 16.9 in refined olive-pomace oil, which were distinctive from sunflower oil with 3.7, corn oil with 2.4, and soybean oil with 2.0. It can provide important indicator of olive oil adulteration with other cheap vegetable oils. The results of this study can be used as a database for the classification of olive oil grade and distinguishing between the different types of oils.

• Korean Journal of Food Science and Technology
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• v.49 no.3
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• pp.235-241
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• 2017

Generally, peanuts are classified as high-fat foods as they possess high proportions of fatty acids. This study compared lipid constituents and properties between normal and high-oleic peanuts. Gas Chromatography-Flame Ionization Detector (GC-FID) analyses revealed that the fatty acid levels were significantly different between the normal and higholeic peanuts (p<0.05). Eight fatty acids were identified in the samples, including palmitic (C16:0), stearic (C18:0), oleic (C18:1, n9), linoleic (C18:2, n6), arachidic (C20:0), gondoic (C20:1, n9), behenic (C22:0), and lignoceric (C24:0) acids. Four tocopherol homologs were detected, and ${\alpha}$- and ${\gamma}$-tocopherols were the predominant ones. Tocopherols were rapidly decomposed during 25 day storage at $80^{\circ}C$. The main identified phytosterols were beta-sitosterol, ${\Delta}^5$-avenasterol, campesterol, and stigmasterol. Acid and peroxide values indicated that high-oleic peanuts have better oxidative stability than normal peanuts. These results can serve as the basis for the use of peanuts in the food industry.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.591-600
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• 2013

This study investigated the changes in the nutraceutical lipid components of brown rice oil after germination. Four different high-yielding cultivars (Dasan1, Segyejinmi, Hanareum1 and Hanareum2) of Korean brown rice were selected and brown rice oil was extracted from each cultivar before and after germination. Free fatty acid, squalene, policosanols, and isomers of phytosterol were analyzed using GC, and isomers of tocols (tocopherol and tocotrienol) and ${\gamma}$-oryzanol were quantified using HPLC from both brown rice oil (BRO) and germinated brown rice oil (GBRO). The contents of phytosterol isomers, campesterol, stigmasterol, and ${\beta}$-sitosterol were increased by 8.3%, 31.6%, 3.3% in GBRO, respectively. Furthermore, the squalene content showed the highest increase of up to 2.4 fold in GBRO compared to BRO. In addition, linoleic and linolenic acid composition increased whereas oleic and palmitic acid decreased in the GRBO. However, the contents of tocols (tocopherol and tocotrienol) in GBRO were lower than those in BRO, and there was no significant difference in policosanol and ${\gamma}$-oryzanol between GBRO and BRO. These results suggest that GBRO has the potential as a healthy and functional source due to its lipid profile on improved lipid metabolism.