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재래식 및 개량식 된장의 아이소플라본 분포 및 β-glucosidase 활성 연구
한국식품과학회 한국식품과학회지 제42권 제2호 2010.04 pp.125-129
※ 원문제공기관과의 협약기간이 종료되어 열람이 제한될 수 있습니다.
Isoflavone distribution and β-glucosidase activity in 16 commercially available doenjang samples were determined. Twelve of the samples were home-made doenjang (HMD) with a relatively long fermentation period and 4 of the samples were factory-produced doenjang (FPD) from four different manufactures. Total isoflavones (TI) in the HMD ranged from 370-723 μg/g, while those in FPD ranged from 179-537 μg/g. The isoflavone distribution in HMD was different from those in FPD. Generally, the TI in HMD was higher than those in FPD. The major isoflavone was aglycones, which ranged from 42.98 to 89.96% in HMD and from 35.51 to 93.48% in FPD. Isoflavones in the β-glucoside forms were not detected in tested FPD samples. Principal components analysis (PCA) of the isoflavone profiles showed that HMD were differentiated from FPD. First principal component (PC1) and second principal component (PC2) expressed 43.6 and 22.9% of the data variability, respectively. β-Glucosidase activity in doenjang was lower than that in raw soybeans. The results of this study can be used to understand the differences in the isoflavone distribution in traditionally manufactured and factory produced doenjang.
Picrate, enzyme-picrate and instrumental analysis methods using IC (Ion Chromatography) and HPLC (High Performance Liquid Chromatography) were compared for their effectiveness in determining cyanide in extracts of Maesil, which is classified as a harmful substance. First, the picrate method showed the shortest analysis time (about 5 hr). The color of picrate paper changed at 0.01 mg/200 mL CN−. However, it was difficult to detect cyanide from amygdalin of glucosides. Second, we performed a qualitative analysis for total cyanide (free cyanide and cyanide from amygdalin) by the enzyme-picrate method using β-glucosidase and a quantitative analysis by spectrophotometry. Finally, analysis of cyanide by IC and HPLC required the longest determining time (about 17 hr) as well as pretreatment for each free cyanide and amygdalin. These results suggest that enzyme-picrate is the most effective analysis method for the detection of cyanide in Maesil extracts.
광자극발광법(PSL)에 의한 방사선 조사 건조향신료의 검지 특성
한국식품과학회 한국식품과학회지 제42권 제2호 2010.04 pp.136-141
※ 원문제공기관과의 협약기간이 종료되어 열람이 제한될 수 있습니다.
This study attempted to determine whether Photostimulated Luminescence (PSL) is applicable for the detection of post-irradiated foods by measuring the PSL photon counts of unirradiated and irradiated dried spices and herbs. A total of 19 dried spices and herbs was irradiated with a 60Co γ-ray source at 1, 5 and 10 kGy followed by measurement of PSL photon. The photon counts of unirradiated samples below 700 correspond to negative. Fifteen samples irradiated over 1 kGy showed photon counts of more than 5,000, indicating irradiation treatment. Intermediate counts (photon count 700- 5,000) were observed in irradiated white/black pepper, nutmeg and cinnamon bark at 10 kGy. These results suggest that it is possible to detect whether dried spices and herbs were irradiated by analyzing PSL, with the exception of white/black pepper, nutmeg and cinnamon bark. Irradiated white/black pepper, nutmeg and cinnamon bark containing low levels of minerals were not sensitive to PSL. Therefore, further investigation is sugguested to be performed by Thermoluminescence (TL) analysis or another validated or standardized method.
Mono sodium glutamate (MSG) 발효 GABA의 수면유도 효과
한국식품과학회 한국식품과학회지 제42권 제2호 2010.04 pp.142-146
※ 원문제공기관과의 협약기간이 종료되어 열람이 제한될 수 있습니다.
Relatively large amounts of GABA can be produced by the fermentation of rice bran. Therefore, this study was conducted to investigate the effects of GABA on the secretion of melatonin and serotonin for the development of a sleep inductive compound. The secretion levels of melatonin and serotonin from mice were found to be 3.425±0.182 pg/mL and 5.37±0.963 ng/mL, respectively, in response to feeding 120 mg/mL of GABA while they were 2.607±0.41 pg/mL in the control. The secretion of both melatonin and serotonin was increased up to the 13.51% and 34.99%, respectively, when compared to the negative control. However, the feeding of milk alone did not have a great effect on the melatonin and serotonin secretions. Conversely, feeding of milk with GABA enhanced the secretion of serotonin. The amounts of both melatonin and serotonin secreted increased with respect to the increase in GABA concentrations during feeding. Interestingly, the induction level of melatonin was relatively higher than that of serotonin in response to feeding 120 mg/ mL of GABA. This is the first study to report that GABA has an ability to induce sleep related hormones in mice; therefore, it has the potential for use as a natural sleep aid.
저염 굴비 제조 시 열풍건조 온도에 따른 화학적 특성 변화
한국식품과학회 한국식품과학회지 제42권 제2호 2010.04 pp.147-154
※ 원문제공기관과의 협약기간이 종료되어 열람이 제한될 수 있습니다.
Gulbi, made of fresh yellow corvenia (Psendosciaena manchurica) that has been salted and dried, is one of the most popular traditional marine foods in Korea. The objective of this study was to develop a method to safely manufacture Gulbi with low levels of oxidation and contamination, by a hot air drying method. Changes in total acidity, pH, salt concentration, thiobarbituric acid-reactive substance (TBARS) and volatile basic nitrogen (VBN) were measured during drying at 30, 35 and 40oC for 15 days in a hot air-dryer using a semi-dried method. Acidity increased with increasing drying time at all drying temperatures. The pH decreased gradually with increasing drying time. Salt concentration was increased as drying time increased at all drying temperatures due to moisture loss. The VBN increased as drying time increased for all drying temperatures. Data indicate that the drying at 35oC appears to have a significant sensory and physicochemical advantage in Gulbi products.
The antimicrobial activity of Sargassum fulvellum (SF) was investigated using the agar diffusion assay and MIC test. In addition, the stability of this activity under extreme heat and pH conditions was examined. The SF ethanol extract was shown to display strong antimicrobial activities against B. subtilis, C. perfringens, L. plantarum, S. aureus, L. monocytogenes, S. cerevisae and C. tropicalis in the agar diffusion assay at the concentration of 4 mg/mL. The MIC value of the SF ethanol extract against the tested microbes ranged from 0.05 to 0.0063%. In the heat and pH stability test, the antimicrobial activity of the SF ethanol extract was not altered when the temperature was maintained at 121oC for 15 min, and it was also not affected in the pH range of 2-10. These results suggest that the SF ethanol extract is highly stable against drastic changes in temperature and pH.
This study examined the safety of various salts (domestic purified salt, domestic solar salt, imported purified salt, imported solar salt) as well as the effects on the quality of kimchi fermented during 28 days at 4oC. All salts contained DEHP, but ferrocyanide ion and heavy metals (Cd, Pb, As, Hg) were not detected. Following fermentation, the pH of kimchi was decreased during storage, but total acidity and salinity values increased. There was no considerable differences between the various salts. As the fermentation period increased, the lactic acid bacterial counts increased remarkably. Regarding the sensory characteristics of kimchi during storage, the appearance of domestic purified salt was better than that of domestic solar salt following fermentation. Imported salts produced a strong salty taste initially, but domestic refined salt had the highest salty taste at 7 days. Therefore, there were no considerable differences between the various salts.
Whey protein isolate가 첨가된 저지방 버터 스폰지 케이크의 품질 특성
한국식품과학회 한국식품과학회지 제42권 제2호 2010.04 pp.165-174
※ 원문제공기관과의 협약기간이 종료되어 열람이 제한될 수 있습니다.
The effects of substituting whey protein isolate (WPI) for butter in the preparation of butter sponge cake were determined by objective and subjective tests. The specific gravity of cake batter, the cooking loss and moisture content of cake were all decreased with increasing amounts of WPI, whereas specific loaf volume was increased. With increasing WPI content, redness of crust and crumb, as well as lightness of crumb were increased, whereas lightness of crust, as well as yellowness of crust and crumb were all decreased. Hardness, chewiness, gumminess, adhesiveness and fracturability were increased significantly with increasing amounts of WPI, however, cohesiveness, springiness, and resilience were decreased. In the sensory evaluation, 20% WPI-substituted cake displayed scores similar to those of control. These results suggest that substitution of 20% WPI could be the best ratio for the preparation of butter sponge cake.
Differences in physiochemical characteristics of row waxy rice, steeped in optimum steeping conditions (31.5oC, 9 days) were investigated along with the relationship between these properties and the quality characteristics of Gangjung made from ten different varieties of waxy rice in order to identify the optimal waxy rice variety for making Gangjung. The moisture content of ten waxy rice varieties was increased, but protein and ash contents were decreased during steeping. Mineral analysis, showed that the Fe, Mg, Ca, Na and K contents of all samples were decreased during steeping. Regarding the gelatinization behavior of the ten waxy rice varieties, the peak viscosity and breakdown were increased with the exception of Backjinju and Backjinju-1 during steeping. Shinsunchalbyeo was the most adaptable waxy rice variety for making Gangjung, as its tested scores for expansion ratio and crispness were higher than other waxy rice varieties. The textural properties of Gangjung made from Backjinju and Backjinju-1 had the highest levels of hardness and showed the lowest expansion ratios. Therefore, Backjinju and Backjinju-1 are considered the worst varieties for making Gangjung.
This study examined the quality characteristics and antioxidant activities of cookies added Pleurotus eryngii powder. There were no significant differences in bulk density or water content between the doughs. Spread factors and leavening rates of cookies decreased with increasing Pleurotus eryngii powder content. However, the loss rates of cookies showed no significant differences. L values decreased with increasing Pleurotus eryngii powder content while a values were gradually increased. b values showed no significant differences among the samples. Hardness, total phenol compound content, ferric reducing antioxidant power (FRAP) and DPPH radical scavenging activity of cookies were significantly increased with increasing Pleurotus eryngii powder content. In a descriptive test, the color, flavor, palatability, hardness and graininess were all increased with increasing Pleurotus eryngii powder content. In a preference test, color and flavor were the highest in the 10% group without significant differences. Texture was preferred in the control-20% groups without significant differences. However, taste and overall acceptability were the highest in the 10% group.
Changes in the quality of buckwheat sprout treated with organic acid solutions such as ascorbic, citric and acetic acid were examined during storage in order to judge the feasibility of acid dipping as a pretreatment for extending shelf-life. Quality attributes of buckwheat sprout stored at 5oC were measured in terms of microbial cell count, moisture content, soluble solids content, chromaticity, and sensory evaluation over different storage times. For microbial growth inhibition, combinations of 0.05% acetic acid and 0.5% citric acid or 1% ascorbic acid and 0.5% citric acid were more effective than other treatments. Slight changes were observed in moisture content among the treatments, whereas soluble solids content of each treatment was increased during storage. In chromaticity, the Hunter‘s a value of buckwheat sprout treated with acetic acid alone or acetic acid combinations showed the largest increase. Dipping treatment with ascorbic acid and citric acid produced only slight changes in color of the sprout. In the sensory evaluation of discoloration (head, stem and root), wilting and overall quality, ascorbic acid and citric acid treatments gave the highest scores. These results suggest that dipping treatment of buckwheat sprout with citric acid can confer more positive effects on storage stability than others.
42번째 alanine 잔기의 proline 치환에 의한 보리 α-amylase isozyme 2의 대장균 내 발현 증가 및 기질특이성 변화
한국식품과학회 한국식품과학회지 제42권 제2호 2010.04 pp.198-203
※ 원문제공기관과의 협약기간이 종료되어 열람이 제한될 수 있습니다.
Although barley α-amylase isozyme 1 (AMY1) and 2 (AMY2) share up to 80% of amino acid sequence identity, their enzymatic properties differ remarkably. In this study, the 42nd alanine residue of AMY2 was replaced with another random amino acid via saturation mutagenesis. Eight out of 370 recombinant E. coli cells showing enhanced starch-hydrolyzing activity were characterized as possessing the same proline residue instead of alanine. Even though the specific activity of AMY2-A42P is reduced to 81% of wild-type, its expression level and purification yield were enhanced by approximately 2 and 4 times that of AMY2, respectively. Characterization of its enzymatic properties confirmed that AMY2-A42P is similar to that of wild-type. However, its specificity to starch substrates is likely to be intermediate between AMY1 and AMY2.
Kocat-D1의 streptozotocin으로 유도한 당뇨모델에 대한 항당뇨 활성
한국식품과학회 한국식품과학회지 제42권 제2호 2010.04 pp.204-209
※ 원문제공기관과의 협약기간이 종료되어 열람이 제한될 수 있습니다.
This study was conducted to investigate the anti-diabetic activity of Kocat-D1, which is widely used in traditional medicine to treat diabetes in Shandong, China. Sprague Dawley rats (8 weeks of age) were separated into 4 groups: a normal control, streptozotocin (STZ)-induced diabetic rat group (DM control), Kocat-D1-1 (diabetic rat treated with 0.25 g/kg/day hot water extract), and Kocat-D1-2 (diabetic rat treated with 1 g/kg/day hot water extract). After eight weeks of treatment, the fasting blood glucose levels of the Kocat-D1-1 (334.3±32.9 mg/dL) and Kocat-D1-2 group (259.5±35.0 mg/dL) were significantly lower when compared to the DM control group (451±42.6 mg/dL). Furthermore, the levels of glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT), albumin and high-density lipoprotein (HDL) cholesterol in the serum of the Kocat-D1-2 group were significantly normalized when compared to the DM control group. However, significant differences were not observed between the Kocat-D1-1 group and the DM control group. Histochemical staining of the liver of the Kocat-D1-2 group revealed no fat accumulation. The insulin level was significantly upregulated in the Kocat-D1-2 group (0.13±0.02 ng/mL) when compared to the DM control group (0.05±0.04 ng/mL). The relative volume of β-cells in the pancreas of the Kocat-D1-2 group (49.4±4.2%) also increased significantly when compared to the DM control group (12.9±7.9%). These results suggest that Kocat-D1 exerts an anti-hyperglycemic effect through the enhancement of insulin secretion.
해당근 추출물의 항산화 활성 및 최종당화산물에 의한 혈관내피세포 기능장애 억제활성
한국식품과학회 한국식품과학회지 제42권 제2호 2010.04 pp.210-216
※ 원문제공기관과의 협약기간이 종료되어 열람이 제한될 수 있습니다.
Rosa rugosa has traditionally been used as a folk remedy for diabetes. The objective of this study was therefore to demonstrate the inhibition of endothelial dysfunction activities through antioxidants and the anti-glycation of Rosa rugosa roots. Dried roots of Rosa rugosa were boiled in methanol for three hours, evaporated and lyophilized with a freeze-dryer. The methanolic extract of Rosa rugosa roots (RRE) was tested for antioxidant activities by measuring total polyphenol (TP) content, flavonoid content, 1,1-diphenyl-2-picrylhydrazyl free radical-scavenging activity (DPPH) assay, and ferric-reducing antioxidant power (FRAP) assay. The total TP content, flavonoid content, FRAP value, and DPPHSC 50 are 345.2 μg gallic acid equivalents/mg dry matter (DM), 128.1 μg quercetin equivalents/mg DM, 2.2 mM FeSO4/mg DM and 34.2 μg DM/mL, respectively. Treatment of RRE significantly lowered fluorescent formation due to advanced glycation reaction. In addition, reactive oxygen species (ROS) scavenging assay, monocyte adherent assay and transendothelial electrical resistance (TEER) assay were performed to investigate the possibility that RRE improves endothelial dysfunction-induced diabetic complications. The adhesion of THP-1 to treated HUVEC with RRE (100 μg/mL; 33% and 500 μg/mL; 75%) was significantly reduced compared to HUVEC stimulated by glyceraldehydes-AGEs (advanced glycation end product). The TEER value (88 Ω·cm2) of stimulated HUVEC by glyceraldehydes-AGEs was reduced compared to non-stimulation (113 Ω·cm2). However, normalization with RRE increased endothelial permeability in a dose-dependent manner (100 μg/mL; 102 Ω·cm2 and 500 μg/mL; 106 Ω·cm2). Thus, these results suggest that Rosa rugosa roots could be a novel candidate for the prevention of diabetic complications through antioxidants and inhibition of advanced glycation end product formation.
식이 폴리페놀 성분 resveratrol과 일반의약품의 복합처리에 의한 간 및 장관계 세포독성 평가
한국식품과학회 한국식품과학회지 제42권 제2호 2010.04 pp.217-222
※ 원문제공기관과의 협약기간이 종료되어 열람이 제한될 수 있습니다.
Resveratrol is a natural polyphenolic compound frequently found in grapes. The biological actions of resveratrol have been extensively investigated both in vitro and in vivo. The interactions of resveratrol with commonly-consumed drugs, however, have rarely been studied. In this study, the cytotoxic properties of resveratrol on the hepatic and intestinal cells in the presence of over-the-counter (OTC) drugs, including acetaminophen (AAP), aspirin (Asp), and ibuprofen (Ibu), were evaluated. The cytotoxic effects of resveratrol on hepatic HepG2 and colonic HCT 116 cells were not markdely changed in the presence of AAP, Asp, or Ibu. Conversely, the cytotoxicity of OTC drugs was not affected by resveratrol either. Concentrations of resveratrol below 10 mM significantly increased HepG2 cell growth after 48 or 72 hr incubation; however, the growth-stimulating effect was not observed in the presence of AAP. When HCT 116 cells were treated with OTC drugs before or after resveratrol, the cytotoxic effects were not significantly altered. The present study provides basic information for the potential health effects of the interactions between resveratrol and commonly-consumed OTC drugs.
면역활성 증진을 위한 수삼의 상황버섯 균사체 고체배양으로 조제된 수삼발효물로부터 활성 다당류 분획
한국식품과학회 한국식품과학회지 제42권 제2호 2010.04 pp.223-232
※ 원문제공기관과의 협약기간이 종료되어 열람이 제한될 수 있습니다.
Crude polysaccharide (WG-PL-CP) was fractionated from fermented ginseng with Phellinus linteus in solid culture to enhance the immunostimulation of ginseng. WG-PL-CP produce three active polysaccharide-rich fractions (WGPL- CP-II, III, and IV) on DEAE-Sepharose CL-6B (Cl− form). WG-PL-CP-III displayed higher mitogenic activity (1.98- fold of the saline control at 100 μg/mL) than did WG-CP-III or PL-CP-III (1.60- or 1.65-fold, respectively), and potent intestinal immune system modulating activity through Peyer's patch was obtained by WG-PL-CP-IV only (1.56-fold). Meanwhile, WG-PL-CP-II and III significantly enhanced macrophage stimulating activity (2.01- and 1.94-fold) compared to WG-CP-II and III (1.73- and 1.66-fold) or PL-CP-II and III (1.79- and 1.72-fold). In addition, WG-PL-CP-III and IV mainly contained neutral sugar (73.5 and 67.3%) and uronic acid (23.2 and 24.6%). Component sugar analysis also showed that WG-PL-CP-III consisted mainly of uronic acid as well as the neutral sugars Glc, Ara, Gal, Rha and Xyl (molar ratio of 0.81:1.00:0.49:0.42:0.28:0.20), whereas WG-PL-CP-IV was mainly comprised of uronic acid, Ara, Rha, Gal, Xyl and Glc (1.00:0.75:0.69:0.63:0.42:0.34). Therefore, it is assumed that these active polysaccharides play an important role in enhancing the immunostimulation of fermented ginseng with P. linteus in solid culture.
This study was conducted to examine the anticancer activities of Berberis koreana extracts according to different extraction processes. The highest extraction yield obtained was 8.26% following extraction by ultrasonification at 60 kHz and 60oC followed by high pressure at 500MPa. Generally, the extracts from the ultrasonification process showed relatively low cytotoxicities against the human normal cell line, HEK293 showing as low as 15%. This extract inhibited the growth of the digestive related organs cell lines, human stomach adenocarcimoma cell and human epithelial adenocarcinoma cell by up to 80% when administered at 1.0 mg/mL, and showed 2.5-3.5 of selectivity. It was also found that this extract induced the production of nitric oxide levels as high 37.87 μM from macrophages. For the in vivo experiment using ICR mice, the total serum IgG levels of mice treated with B. koreana extracts from ultrasonification extraction were increased by up to 57 ng/mL. The survival time of this group was longer than that of the other group after the injection of Sarcoma-180 and the increment of their body weights was also greatly suppressed. In addition, the extract showed the highest tumor inhibition activities, leading to a reduction of 78.47%. These results indicate that the highest activities of B. koreana associated with this extraction process can be significantly improved.
Brown rice of Korea and China was irradiated at doses ranging from 0 to 15 kGy to verify the identification properties of viscosity measurement by determining the relationship between starch content and specific parameters. The starch contents of brown rice were 71.52 and 64.58% for rice of Korea and China, respectively. Additionally, a higher starch content was associated with a higher viscosity. The viscosity and the corresponding specific parameters decreased significantly as the irradiation dose increased, and these changes were influenced by the spindle speed (50, 150, 300 rpm), with a higher effect being observed at lower speeds. The determination coefficients (R2) describing the relationship between irradiation dose and viscosity values ranged from 0.9423 to 0.9567 in Korean samples and from 0.9119 to 0.9387 in Chinese samples. The viscosity and the corresponding specific parameters enabled identification of the non-irradiated and irradiated brown rice from 30 unknown samples with an accuracy of 90%. Based on these findings, the viscosity and specific parameters can be applied as an additional tool for screening of irradiated brown rice.
Lipozyme TLIM을 효소적 반응촉매로 이용한 glyceryl monooleate로부터의 diacylglycerol의 합성
한국식품과학회 한국식품과학회지 제42권 제2호 2010.04 pp.246-249
※ 원문제공기관과의 협약기간이 종료되어 열람이 제한될 수 있습니다.
Diacylglycerol (DAG) was produced from lipase by the catalyzed synthesis of soybean oil (SBO) and glyceryl monooleate (GMO) with Lipozyme TLIM (Thermomyces lanuginosa). Effects of reaction time, molar ratio and enzyme road were studied. When 2:1, 1:1 and 1:2 (SBO:GMO) molar ratios with 20% Lipozyme TLIM were applied in a 1-hr reaction, the concentrations of DAG produced were 17.8, 20.0 and 20.4 g/100 g oil, respectively. Different amounts (2, 5, 10 and 20%) of Lipozyme TLIM were used at a 1:2 (SBO:GMO) molar ratio, and the concentrations of DAG produced in a 1-hr reaction were 10.8, 14.0, 16.9 and 20.4 g/100 g oil, respectively. During a 72-hr reaction, 10.8-22.7 g/100 g oil of DAG were produced under the reaction conditions in this study.
메꽃(Calystegia japonica) 잎 추출물의 함유성분과 생리활성에 관한 연구
한국식품과학회 한국식품과학회지 제42권 제2호 2010.04 pp.250-255
※ 원문제공기관과의 협약기간이 종료되어 열람이 제한될 수 있습니다.
This study examined the physiological activities as well as the total polyphenol and flavonoid content of water extract (WE), ethanol extract (EE) and hot water extract of Calystegia japonica leaves under high pressure (HWE). The xanthine oxidase inhibitory rate of EE was the highest with a value of 98.89% at a concentration of 1.0 mg/mL, whereas the rate of WE and HWE was over 90% at a concentration of 0.3 mg/mL. The superoxide dismutase (SOD)-like activity of HWE was the highest at 18.88%. The nitrite scavenging abilities were 64.59-66.46% at conditions of pH 1.2 and 1.0 mg/mL, and 52.78-55.89% at pH 3.0. The electron donating ability of EE was the highest with a value of 84.80% at a concentration of 0.1 mg/mL. All extracts showed the highest degree of electron donating at the concentration of 0.1 mg/ mL, and this effect decreased as the extract concentration increased. The EE had the highest content of total polyphenol compound (173.89 mg/g) and flavonoid compounds (40.68 mg/g).
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