• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1418-1425
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• 2000

Obesity and diabetes mellitus are associated with common pathogenic mechanism, and ${\beta}-glucan$ of Agaricus blazei Murill is potent inhibitor of intestinal ${\alpha}-glycosidase$ and inhibit the digestion of starch and sucrose in the small intestine. In this studies, there was observed the anti-hyperglycemic effect in obese diabetic mice(C57BLKsJ db/db), which were supplied Agaricus and Acarbose for 5 weeks. In db/db mice, food intake and body weight gain were decreased significantly in Agaricus groups(p<0.05). Also these group exhibited lower fasting serum glucose level compared with control group. HbA1c level, triglyceride level, total cholesterol level, HDL cholesterol level, LDL cholesterol level and VLDL cholesterol level were lowered in db/db mice. The activity of disaccharidases on proximal and distal segments of small intestine was decreased. In conclusion, it was assumed that ${\beta}-glucan$ of Agaricus blazei Murill has anti-hyperglycemic and anti-obesitic effects by reducing food intake and body weight gain, and also decreasing serum glucose and lipid level through inhibiting the activity of small intestinal disaccharidases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.2035-2041
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• 2013

The effects of Aspergillus oryzae rice koji (AO) and Asp. kawachii rice koji (AK) as enzyme preparations, on the quality characteristics of rice mash were invested in this study. The amount of AORM (Asp. oryzae rice mash) and AKRM (Asp. kawachii rice mash) were 50, 100, 200% (w/w) based on 100 g of rice. Firstly, in the titer measurement result on the ${\alpha}$-amylase and glucoamylase activities of AO and AK. On the other hand, the acid protease activity has values of 31.56 unit for AO and 849.17 unit for AK. The sugar solid of the AORM and AKRM groups significantly increased as the rice koji ratio on rice was higher, which were shown with values as high as 17.63~20.53 and 17.51~19.28, respectively. Glucose and maltose were detected for free sugar of AORM. Only glucose was found in AKRM. Citric acid, malic acid, and lactic acid were detected as the organic acid of KORM; oxalic acid, citric acid, and succinic acid were detected for AKRM, and the content increased as the rice koji ratio on rice increased (P<0.05). From the above result, rice koji with useful mold is expected to be used broadly in foods by looking at the fact that it has starch degradation ability and organic acid producibility.

• Journal of Nutrition and Health
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• v.7 no.1
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• pp.17-23
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• 1974

Digestibilities of flour of white wheat, barley, potato, sweet potato, are $5{\sim}11$ percent (3hrs.) in unripe starch state and in gelatinization, digestibilities are up to $20{\sim}30$ percent (3hrs.). And in two states, digestibilities of flour of potato and sweet potato are lower than barley and white wheat flour. If it is not gelatinization, digestibilities of biscuit and cracker are much lower than popped cake (29%). In gelatinization, digestibilities of biscuit and cracker $(19{\sim}29%,\;3hrs.)$ are similar to gelatinized flour of materials. Digestibilities of bread and castern is $21{\sim}32$ percent, it is similar to gelatinized flour of materials. And bread is higher than castera. Digestibility of on the marketing weaning food (II) (15%, 3hrs.) is much lower than food (I) (24.1%, 3hrs.) When the date of manufacturing passed $1{\sim}2$ months, digestibility of some cookies have a tendency to low. When mothers choice the infant weaning food, they consider metritional value (42%) and digestibility (27%). Also when they make weaning food at home, they generally use flour of rice (41%) and white wheat (23%). And they think, the rate of digestion is 49% in the rice flour and white wheat (23%). It was sort of cooked of rice (16%) and weaning food on the marketing(13%), which accepts to good digest. Also it was sort of biscuits (44%) which comparatively high choice snack food.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.1
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• pp.76-82
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• 2009

Wheat is the most widely cultivated cereal and an important source of dietary protein worldwide. Wheat allergy, defined as an adverse immunologic reaction to wheat, encompasses a broad spectrum of disorders with different pathomechanisms and clinical manifestation. The Nuruk, a traditional Korean Koji for brewing, was made with wheat flour and fermenting microbes such as bacteria, yeast and mold. The strains grown on Nuruk secrete various enzymes as amylase and protease. By the activation of such enzymes, starch and proteins in Nuruk are hydrolyzed to sugar and amino acid. Therefore, it is supposed to reduce allergic proteins in wheat. To study quality properties and degradation degree of allergenicity in Nuruk by fermentation, we investigated the changes of general ingredients and allergenicity in Nuruk during fermentation. Moisture contents was decreased from 24.2% to 13.6% during fermentation. Crude lipid and protein contents were gradually increased during fermentation. After 15 days of fermentation, reducing sugar and total sugar contents were reached its maximum level, and they were 27.45% and 39.00%, respectively. Acid and neutral protease activity were significantly increased during fermentation, but alkaline protease activity was not detected. ${\alpha}$-amylase activity was gradually increased and showed maximum level about 2,833.00 U/g after 15 days of fermentation. Glucoamylase activity was the highest level about 497.9 U/g after 10 days of fermentation. The increase of these proteolytic and saccharogenic enzyme activities will provide efficient condition for production of rice wine. Also, protein fractions were isolated from Nuruk, and degradation of these proteins during fermentation were confirmed by SDS-PAGE. IgE immunoblotting using patient's sera with wheat allergy was performed to confirm allergenic protein in Nuruk. These results as fermentation of Nuruk will provide a useful tool for developing safer wheat products to prevent wheat allergy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1472-1478
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• 2008

Four kinds of wild grape Yakju were fermented with wild grape and cereal such as rice, glutinous rice, barley or millet, and their quality characteristics were investigated. Reducing sugar, total sugar, and activities of $\alpha$- and $\beta$-amylase decreased until 2nd day, increased on 3rd day, and gradually decreased after 5 days of fermentation. Reducing sugar content was in the order of glutinous rice> barley> rice> millet group, and this was consistent with the result of $\beta$-amylase activity. Total sugar content was in the order of glutinous rice> rice> barley> millet group, and it was consistent with starch content of each cereal. Alcohol content decreased after 2 days, then glutinous rice group gradually increased from 3 days whereas other groups showed no difference from 5 days of fermentation. pH decreased until 2 days of fermentation, slightly increased and then showed almost no change after 5 days of fermentation. Total acid increased until 2 days, then decreased on 3rd day of fermentation, and gradually increased in the order of barley> millet> rice> glutinous rice group. L value was the highest in the initial day of fermentation, however it decreased with fermentation time. While a value was also the highest in the initial day of fermentation, it gradually decreased after slightly increasing in 3 days of fermentation. In contrast, b value was the lowest in the initial day of fermentation. It greatly increased until 3 days, then decreased on 5th day of fermentation and gradually increased again. Groups of rice and glutinous rice had more brown color than those of barley and millet. In the sensory evaluation, wild grape Yakju using rice was the most preferred in taste, flavor, and overall preference.

• Journal of Genetic Medicine
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• v.4 no.1
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• pp.72-79
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• 2007

Purpose : Glycogen storage disease type III (GSD-III) is a rare autosomal recessive disorder of glycogen metabolism. The affected enzyme, amylo-1,6-glucosidase, 4-alpha-glucanotransferase (AGL, glycogen debranching enzyme), is responsible for the debranching of the glycogen molecule during catabolism. The disease shows clinical and biochemical heterogeneity, reflecting genotype-phenotype heterogeneity among different patients. In this study, we aim at analyzing mutations of the AGL gene in three unrelated Korean GSD-III patients, and characterizing their clinical and laboratory findings. Methods : We characterized the clinical features of three unrelated Korean GSD-III patients by biochemical, histological and imaging studies. The 35 exons and part of exon-intron boundaries of AGL were analyzed by direct sequencing using genomic DNA extracted from the peripheral leukocytes of patients. Results : Diverse clinical features were observed in these patients including hepatomegaly (all patients), seizures (patient 2), grow th failure (patients 1 and 2), hyperlipidemia (patients 1 and 3), raised transaminase and creatine kinase concentrations (all patients), and mild cardiomyopathy (patient 2). Liver transplantation w as performed in patient 2 due to progressive hepatic fibrosis. A dministration of uncooked corn starch maintained normoglycemia and improved biochemical and growth profiles. DNA sequence analysis revealed mutations in 5 out of 6 alleles. Patient 1 was a compound heterozygote of c.1282 G>A (p.R428K) and c.1306delA (p.S603PfsX6), patient 2 had c.1510_1511insT (p.Y 504L fsX 10), and patient 3 had c.3416 T >C (p.L 1139P) and c.1735+1 G>T (p.Y 538_R578delfsX 4) mutations. A part from the p.R428K mutation, the 4 other substitutions identified w ere nov el. Conclusion : GSD-III patients display variable phenotypic characteristics resembling those of GSD-Ia. Molecular defects in the AGL gene of Korean GSD-III patients are genetically heterogeneous.

• Food Science and Preservation
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• v.31 no.1
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• pp.149-160
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• 2024

Dextran is a glucose homo-polysaccharide with a predominantly α-1,6 glycosidic linkage of microbial source and is known to be produced primarily by lactic acid bacteria. However, it can also be obtained through the dextran dextrinase of acetic acid bacteria (Gluconobacter oxydans). The dextrin-based dextran was obtained from rice starch using G. oxydans fermentation of rice hydrolysate, and its properties were studied. Both dextrin- and rice hydrolysate-added media maintained the OD value of 6 after 20 h of incubation with acetic acid bacteria, and the gel permeation chromatography (GPC) analysis of the supernatant after 72 h of incubation confirmed that a polymeric material with DP of 480 and 405, which was different from the composition of the substrate in the medium, was produced. The glucose linkage pattern of the polysaccharide was confirmed using the proton nuclear magnetic resonance (¹H-NMR) and the increased α-1,4:α-1,6 bond ratio from 0.23 and 0.13 to 1:2.37 and 1:4.4, respectively, indicating that the main bonds were converted to α-1,6 bonds. The treatment of dextrin with a rat-derived alpha-glucosidase digestive enzyme resulted in a slow release of glucose, suggesting that rice hydrolysate can be converted to dextran using acetic acid bacteria with glycosyltransferase activity to produce high-value bio-materials with slowly digestible properties.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2001.12a
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• pp.39-74
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• 2001

The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s∼1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great, progress and success was obtained in development of high-quality japonica cultivars and qualify evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice caltivars and special rices adaptable for food processing such as large kernel, chalky endosperm aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice and the palatability of cooked rice. The water/rice ratio (in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and torture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak. hot paste and consistency viscosities of viscogram with year difference. The high-quality rice variety “Ilpumbyeo” showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic mcroscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high Probability of determination. The ${\alpha}$ -amylose-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, shelved the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogiadation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice bread. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large gram rices showed better suitability for fermentation and brewing. Our breeding efforts on rice quality improvement for the future should focus on enhancement of palatability of cooked rice and marketing qualify as well as the diversification in morphological and physicochemical characteristics of rice grain for various value-added rice food processings.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.873-881
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• 2005

This study was conducted to improve the properties of frozen dough foods (buns and noodles etc.) on the quality deterioration with microwave oven cooking. Microwave is a useful cooking method, but it quickly takes moisture from food surface and makes lowering food quality abruptly. For improvement of these problems, mixing doughs with addition of various additives of 34 types manufactured respectively; starches, modified starches, gums and emulsifiers etc. Each mixing dough produced in sheet type $(30{\times}30{\times}1mm)$ and steamed them, was quickly froze at $-70^{\circ}C$ and packed with polyethylene. Packed samples kept at $-20^{\circ}C$ for 48 hours. After they were steam or microwave treatment packed or non-packed with polyethylene, studied for improvement effects of quality as sensory evaluation and selected 6 type additives; modified starches (TA, ST), gums (AR, GA) and emulsifiers (E, S1) as improvement agent. Because moisture loss from microwave oven cooking leads to quality deterioration of frozen dough foods, additive, such as including starches, modified starch, gums, and emusifiers were added to improve dough properties. Amylogram, scanning electron microscopy, textural analysis, and differential scanning calorimetry revealed addition of additives improved textural properties including surface-hardening of frozen dough foods compared to the control.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.28-60
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• 1983

This study was carried out to define the effects of external factors including temperature, moisture, oxygen and light quality on the germination of sesame seeds and to investigate the change of major chemical constituents of seeds during germination. The results obtained are summarized as follows: 1. The average germination ratio was from 95.8% to 97.2% when it was tested every $5^{\circ}C$ intervals from $20^{\circ}C$ to $35^{\circ}C$ and no significant difference in germination ratio was found within $20^{\circ}C$ to $35^{\circ}C$. But the germination ratio dropped rapidly to 32.2% when seeds were germinated at $15^{\circ}C$ and the coefficient of variation become greater(77%) 2. The days required for germination ranged from 1.16 to 1. 64 at the temperatures of $35^{\circ}C$ to $25^{\circ}C$ and they were 3.07 and 10.4 at the temperatures of $20^{\circ}C$ and $15^{\circ}C$, respectively. 3. Considering the germination ratio and days needed, $15^{\circ}C$ was assumed to be the minimum temperature for germination practically and this temperature is recommended for testing low temperature tolerance of seed germination of sesame cultivars. 4. The varieties shown the highest low temperature tolerance were Shirogoma and Turkey. The next varieties shown some degree of low temperature germination were Suweon #29, Naebok and IS 58. The varieties with 70 to 80% of germination ratio were Maepo, Suweon #14, Kimpo, Moondeok, and Haenam. Among the 90 varieties tested, the varieties with comparatively high degree of low temperature tolerance were about 10%, and 70% of the low temperature tolerant varieties were domestic varieties. 5. At $12^{\circ}C$ the Shirogoma was the only variety which showed over 50% of germination ratio, 71.4% of the varieties showed less than 20% of germination ratio. When the temperature was raised to $27^{\circ}C$ 18 days after placement at $12^{\circ}C$ all the varieties showed over 90% of germination ratio within 2days. 6. The amounts of water imbibition needed for seed germination were 0.48 to 0.62 times of the seed dry weight at $25^{\circ}C$ and were significantly different among sesame cultivars. About 63% of water required for germination was imbibed in 2 hours after placement of seeds under the germination condition. 7. Under saturated moisture condition the average germination ratio was 0.42%. In the soil of which water potential was -0.4bar 64.8% of the seeds germinated and the most adequate soil water potential for sesame seed germination was about -0.4 to -5.5 bar. The germination ratio decreased as the soil water potential declined below -5.5 bar. 8. Six out of 10 varieties were not influenced by 5% of oxygen in air germination chamber, while varieties such as Yecheon, PI 158073, IS 103 and Euisangcheon showed 64 to 91% of germination under the 5% oxygen content. Under anaerobic condition, cotyledones were not emerged but only hypocotyl was emerged and elongated. The germination ratio of IS 103 decreased significantly under anaerobic condition. 9. When the seeds were dried for 24 hours after 12 hours imbibition of water, the seeds of Cheongsong did not lose their germination ability and 27.5% was germinated but Suweon #9 and Early Russian failed to germinate. However, the germination ratio of IS 103 decreased when the seed were dried 24 hours after 4 hours imbibition of water and the germination ability of IS 103 was maintained even though the seeds were dried for 24 hours after 24 hours imbibition of water. 10. During germination, sugar content of sesame seed increased rapidly and activity of ${\alpha}$-amylase increased gradually while starch content decreased significantly. The rates of increase in sugar content and enzyme activity and decrease in starch content were significantly lower at $15^{\circ}C$ compared with those at $25^{\circ}C$. 11. During germination of sesame seeds, lipid content in the seeds dropped rapidly and the activity of alkaline lipase increased significantly at early stage of germination. The rate of decrease in lipid content and increase in emzyme activity was lower at $15^{\circ}C$ than at $25^{\circ}C$. 12. Four out of 6 varieties were not affected in germination by light wave length. But Suweon #8 was inhibited in germination by 600-650nm. and IS 103 by 600 to 650nm and 500 to 550nm of light wave length. Suweon #8 showed high germination ratio under 650 to 760 nm and 500 to 560nm, and IS 103 under 400 to 470nm and complete darkness. 13. The germination ratios increased significantly in the seeds of which 1000 grain weight is heavier. When the seeds were placed at soil 4cm deep, Cheongsong and Early Russian failed to emerge their cotyledones, but Suweon #9 and IS 103 showed 32.5 and 50% cotyledone emergence, respectively. The extracts from sesame plant and soil where the sesame was cultivated previously did not affect in the-germination of sesame seeds. 14. The covering by black or transparent polyethylene films increased germination ratio compared with uncovered seeds. The covering was effective in shortening the days needed for germination and in improving the early seedling growth, number of capsules per plant and grain yield. Difference was not so seizable between the two polyethylene films but the transparent film appeared somewhat more effective than the black one. 15. Simcheon, Cheongsong. Suweon #9. PI 158073 and IS 103 showed lower rate of water absorbtion by seed during germination and Suweon #8, Suweon #26, Orotall and Euisangcheon showed high increase in seed weight after water absorbtion by seed.