• Korean Journal of Weed Science
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• v.18 no.4
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• pp.348-355
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• 1998

This study was conducted to identify allelopathic compounds in rye and oat straw extracts by HPLC analysis. These extracts were analyzed with 12 standard chemicals including salicylic acid. 11 chemicals in rye extract except for naringin and in oat extract except for catechin were identified. Salicylic acid(8.34mg/g) in rye straw extracts and naringin(7.50mg/g) in oat straw extracts among these standard chemicals were identified as the largest amount substance. The germination of Chenopodium ablum seeds was significantly inhibited by these chemicals at $10^{-3}$ and $10^{-4}M$ concentrations as compared to control. Salicylic acid in rye and naringin in oat were considered as the major allelopathic substances although allelopathy may be caused by an interaction of many substances. Yet many unidentified chemical compounds are present in both extracts.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.2
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• pp.161-168
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• 1996

This experiment was canied out to determine the effect of cultivar, harvest date and drying method on the changes of moisture content and quality of spring harvest oat(Avena sativa L.) hay. Disign of the experiment was a spilt-split-plot arrangement with early and late cultivars as main plots, early and late harvest dates as sub-plots, and drying agent and tedding as sub-subplots in three replications. Moisture content of early harvest oat was higher than that of late harvest oat by 127.1% dry weight(DW) in 'Swan' and 39.8%DW in 'Foothill'. Moisture content difference between 'Foothill' and 'Swan' was 117.6%DW at early and 204.9%DW at late harvest dates, respectively. Cultivar effect on moisture content of cut oat was higher at late harvest date, but drying method effect was higher at early harvest. Total nitrogen content of early harvest was higher than that of late harvest by 0.70% and that of 'Foothill' was higher than that of 'Swon' by 0.86%. But no difference in total nitrogen content was found between the drying method. ADF and NDF contents were increased at late harvest by 29% and 1 I%, respectively(P<0.05). ADF and NDF contents of 'Swan' were higher than those of 'Foothill' by 2.8% and 4.5%, respectively. No difference in ADF and NDF contents was obtained by drying methods. RFV of early harvest oat hay was 95.1 and 103.8 for 'Swan' and 'Foothill' but late harvest 'Swan' and 'Foothill' showed 74.8 and 85.0, respectively.

• The Korean Journal of Food And Nutrition
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• v.35 no.5
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• pp.324-331
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• 2022

Recently, consumers' awareness of the importance of the intestinal action of lactic acid bacteria and intestinal microbes is increasing, as well as interest in yogurt. In this study, yogurt was prepared with three mixed strains (lactic acid bacteria combination, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp., and Bulgaricus, Streptococcus thermophilussei, 1:1:1) by adding oats flour, and the quality characteristics of yogurt were investigated, while stored at a storage temperature of 4℃ for 12 days. According to the storage period, the control as wel as the oat yogurt showed slight decrease in pH, and no significant change in acidity. Sugar content slightly increased. and brightness decreased, in the control and the oat yogurt. Visible cell numbers increased during storage, and decreased on the 12th day. Viscosity in the oat yogurt was 7,580 cP, which was approximately eight times higher than that of the control group, and decreased gradually according to the storage period. Antioxidant activity (DPPH) was approximately two times higher in the oat-added yogurt, and slightly increased with the storage period, decreased on the 12th day of storage, and β-glucan was detected only in oat-added yogurt.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.271-274
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• 2009

Cereal $\beta$-glucans, linked essentially by mixed $\beta$-(1,4/1,3) glycosidic bonds, were extracted, purified, and structurally identified. Previously chemical structure of barley $\beta$-glucans was characterized from 3 varieties of 'Gang', 'Ohl', and 'Gwangan', and the (1,4)/(1,3) linkage ratio of the $\beta$-glucans was identical. In this study, $\beta$-glucans from 1 barley ('Chal') and 3 oat ('Ohl', 'Samhan', and 'Donghan') varieties were structurally scrutinized, and the linkage pattern of total 7 cereal $\beta$-glucans was compared. The amount of 2 major 3-O-$\beta$-cellobiosyl-D-glucose (DP3) and 3-O-$\beta$-cellotriosyl-D-glucose (DP4) from barley and oat accounted for only 66.6-73.3 and 68.12-81.89% of water-extractable $\beta$-glucan fractions, and the (1,4)/(1,3) linkage ratios of both barley and oat $\beta$-glucans were within very narrow range of 2.27-2.31 and 2.38-2.39, respectively, among the cultivars tested. Structural difference in the cereal $\beta$-glucans was evident when DP3:DP4 ratio in the $\beta$-glucan structure was compared. As a result, this ratio was significantly greater for barley $\beta$-glucan (2.26-2.74) than for oat (1.54-1.66). Chal-B had the greatest DP3 to DP4 ratio among the samples, which in turn reflected the least amount of (1,4)-linkages.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1293-1301
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• 2016

Hulled oat (Chohan) and naked oat (Choyang) flours were analyzed according to particle size to investigate nutritional components and physicochemical properties. Particle size of naked oat flours was larger than that of hulled oat flours. As the mesh of the crushed ones decreased, particle sizes increased in value. The content of total ${\beta}$-glucan was highest in hulled oat flour (4.23%) with 60 mesh and in naked oat flour (4.26%) with 100 mesh. Most total ${\beta}$-glucan was soluble ${\beta}$-glucan in both flours (over 76%). Total starch of hulled oat flours (63.64~69.82%) was higher than that of naked oat flours (52.45~63.71%). Whereas amylose contents showed a negative correlation with total starch contents. Contents of free amino acids increased according to particle size, and each component was dependent on each type of amino acid. Moreover, while fatty acid composition was not significant, the content of most naked oats was higher than that of hulled oats. Besides, the ratio of unsaturated fatty acids (oleic acid and linoleate) in both types of oat flours was relatively higher than that of other grains. The pasting properties of peak viscosity, trough, and breakdown showed the highest value in both oats with 100 mesh. Further, the values of final viscosity and the setback were higher with relatively larger particle size. In addition, peak time exhibited a lower value with larger particle size, whereas it showed the opposite value for pasting temperature. Starch digestibility did not show any specific trend according to particle size, whereas expected glycemic index of hulled oats was lower than that of naked oats. Moreover, lower values were investigated at larger particle sizes. The results of this study provide basic useful information for processing of oat products to improve consumption of oats grown in Korea.

• Proceedings of the Korean Society of Potoscience Conference
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• spring
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• pp.47-50
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• 2003

• Proceedings of the Korean Society of Crop Science Conference
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• 1992.05a
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• pp.20-21
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• 1992

• Proceedings of the Korean Society of Crop Science Conference
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• 1992.05a
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• pp.22-23
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• 1992

• Proceedings of the Korean Society of Crop Science Conference
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• 1992.05a
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• pp.24-25
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• 1992

• Korean Journal of Microbiology
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• v.46 no.3
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• pp.308-312
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• 2010

Deinococcus geothermalis is a moderate thermophillic radiation resistant bacterium producing greater abundance of sugar metabolism enzymes than other Deinococcus species. In this study, optimal condition for xylanolytic activity of D. geothermalis was determined and xylooligosaccharides from oat spelt, beechwood, and birchwood xylan hydrolysates by this organism were analyzed through HPLC. Reducing sugar yield was increased in the order of beechwood, birchwood, and oat spelt xylan. D. geothermalis displayed maximal xylanolytic activity at $40^{\circ}C$ and pH 8.0. Magnesium ion increased xylanolytic activity upto 7.5 fold. Six kinds of xylooligosaccharides (xylose, xylobios, xylotriose, xylotetraose, xylopentaose, and xylohexalose) were detected from beechwood and birchwood xylan reaction products. Among them, xylose was the major product. However, only three kinds of xylooligosaccharides (xylose, xylopentaose, and xylohexalose) were clearly detected from oat spelt xylan. Gamma-ray (50 kGy) treatment of beechwood xylan, birchwood xylan and oat spelt xylan increased xylanolytic activity of D. geothermalis. The results indicate that D. geothermalis and pretreatment of radiation is useful for xylooligosaccharides production.