• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2687-2690
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• 2009

Due to the importance of isoflavone content in soybean extracts, the microwave-assisted process (MAP) was compared to the conventional extraction methods. For comparison of the three methods, all extraction parameters (solvent, sample to solvent ratio, temperature, etc.) were kept the same; the microwave extractor was operated at 187.5 W with an emission frequency of 2450 MHz under atmospheric pressure conditions and the extractions were carried out at 75 ${^{\circ}C}$ for 3 min while the conventional reflux was at 75 ${^{\circ}C}$ for 3 h. Total yield and crude isoflavone content were determined by ultraviolet spectrophotometric and compared with the three methods. Results indicated that the MAP was comparable to the conventional method in its capability to extract target compounds without causing any degradation; in addition it dramatically reduced the extraction time from 3 h to a few minutes, suggesting that it can be an alternative technique to the time-consuming conventional reflux method.

• Journal of Environmental Health Sciences
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• v.31 no.3
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• pp.221-226
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• 2005

Isoflavone was extracted with various concentration of aqueous methanol using whole hypocotyls as the starting material. Whole hypocotyls were preferred as the raw material because the residue could be easily removed from the solvent after the extraction process. Extraction yield was almost constant at the methanol concentration of $20-80\%$. Most of the isoflavone was extracted within 1 hr, and the extraction yield remained almost constant thereafter. When the concentration of methanol was $80\%$, the content of total solid was reduced due to the reduced extraction of contaminating protein as the result of protein insolubilization. Among resins tested, Diaion HP-20, Amberlite XAD-16, and Amberlite IRC-50 showed the highest capacity to absorb the compound. Open column chromatography with Diaion HP-20 showed that $80\%$ aqueous ethanol was most efficient as the eluting solvent with final recovery of the phytochemical being more than $95\%$. Maximum adsorption of the phytochemical occurred at the acidic pH 2-4. When the spatial velocity was increased to 15 and more, the degree of adsorption was decreased, whereas below spatial velocity of 15, the adsorption capacity of isoflavone to the resin was almost constant. The purity of the isoflavone purified by column chromatography was $78\%$.

• Korean Journal of Human Ecology
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• v.14 no.3
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• pp.485-489
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• 2005

The purpose of this study is to investigate changes of isoflavone and nutrients during germination of soybean varieties and to determine the optimal germination condition for soybean processing. After 5 days' germination, water content of the soybeans increased in the order of Poongsannamoolkong> Sinpaldal#2> Black#1> Jinpumkong. Ash content was higher in the order of Poongsannamoolkong> Sinpaldal#2> Jinpumkong> black#1 soybean. All varieties of the soybean samples increased in ash content during germination. Crude fat content was higher in the order of Poongsannamoolkong> Black#1> Jinpumkong> Shinpaldalkong. Crude protein content was higher in the order of Shinpaldalkong> Black#1> Jinpumkong> Poongsannamoolkong. Polypeptide subunits separated from the SDS-PAGE of the entire proteins were showing comparatively high level in the range of 2-16KD in Jinpumkong and 2-21KD in Poongsannamoolkong till the first day of germination, 2-25KD in Sinpaldal#2 till the second day, and 6-27KD in Black#l till the third day. Changes of total isoflavone contents during germination showed different patterns in soybean varieties: Jinpumkong and Black#1 had the highest total isoflavone content on the fourth day of germination, Poongsannamoolkong and Sinpaldal#2 on the first and the second day of germination, respectively.

• Journal of the Korean Society of Food Culture
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• v.29 no.6
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• pp.599-604
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• 2014

This research was conducted to investigate changes in isoflavone contents and sprouting characteristics of germinated soybeans [Glycine max.] under light condition. The relative wet weight of soybeans increased as germination progressed, and it reached $291.1{\pm}14.3%$ at 60 h after beginning of sprouting. On the other hand, relative dry weight slowly decreased as germination progressed. The length of sprouting rapidly increased as germination progressed. The sprouting rate sharply increased from 12 h to 48 h and reached $96.4{\pm}2.5%$ at 60 h after sprouting. In terms of color, L value did not change until 24 h after the beginning of germination, but it rapidly increased from 24 h to 36 h and did not change thereafter. The a value rapidly increased at 24 h after the beginning of germination and decreased thereafter. The b value rapidly increased at early and last stages and reached $9.0{\pm}0.7$ at 60 h after the beginning of sprouting. Total isoflavone reached a maximum level at 12 h after the beginning of germination and consistently decreased thereafter. Among isoflavone compounds, m-genistin had the highest content followed by daidzin and m-daidzin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1430-1437
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• 2016

This study was performed to investigate the changes in isoflavone composition, estrogenic activity and antiestrogenic activity of soybean cultivars of different isoflavone content (Aga 8, Uram, Cheongja 3, and Dawon) with germination. Total isoflavone contents of Aga 8, Dawon and Cheongja 3 was increased from 2,671.74, 261.08 and 2,240.08 to 2,977.50, 966.13 and $2,354.11{\mu}g/g$, respectively after germination except for Uram cultivars, and highest contents of total isoflavone showed $2,977.50{\mu}g/g$ and $2,354.11{\mu}g/g$, respectively in Aga 8 and Cheongja 3 after germination. MTT cell proliferation assay using MCF-7 cells revealed that germinated soybean of Aga 8 and Cheonja 3 obtained not only contained a high content of isoflavone but also had estrogenic activity. Estrogenic activity of Aga 8 and Cheongja 3 soybean extracts increased from 116.21% and 101.60% to 135.34% and 121.05% after germination. These results suggest that germinated soybean of Aga 8 and Cheongja 3 might have a potential preventive effect on estrogen-deficient diseases.

• The Korean Journal of Food And Nutrition
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• v.36 no.5
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• pp.360-367
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• 2023

The major active components of Astragalus membranaceus (AM) are isoflavones, which exist in the form of various glycosides. Nuruk is a traditional fermentation starter in Korea, and is suitable for the biotransformation of isoflavone glycosides because it contains various microorganisms and enzymes. This study was performed to determine changes in the isoflavones and antioxidant properties of AM fermented (AF) with nuruk over 24 hours. AF was sampled after 0, 2, 4, 6, 12, 18, and 24 h of fermentation, and calycosin 7-glucoside, ononin, calycosin, and formononetin content, and the antioxidant properties of AF were analyzed. The total phenolic content increased with fermentation time, and the ABTS radical scavenging activity increased until 6 h of fermentation and then decreased. During fermentation, the isoflavone glycosides decreased significantly as fermentation time increased. The contents of calycosin and formononetin, which are aglycons of calycosin-7-glucoside and ononin, increased from 100.54 ㎍/g to 276.84 ㎍/g and from 56.29 ㎍/g to 123.04 ㎍/g, respectively, at 18 h of fermentation. Significant correlations were observed between fermentation time, isoflavone content, and antioxidant properties. The results of this study showed that fermentation with nuruk is suitable for the biotransformation of isoflavones in AM.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.844-849
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• 2005

The chemical composition of isoflavone, oligosaccharide and phytic acid content of three Korean soybeans, Hwanggumkong, Yakkong and Huktae cultivars, were examined. Moisture, crude fat, crude protein and ash content of soybean seeds were all in the ranges of 10.9-$12.5\%$, 15.8-$20.8\%$, 36.5-$41.1\%$ and 5.4-$5.6\%$ respectively, showing differences among the cultivars. Methionine, cystein and histidine were the minor components of soybean protein and ratio of methionine to the total proteins showed significant varietal differences. The main fatty acids of total lipids were linoleic, oleic and palmitic acids, which comprised over $80\%$ of the total fatty acids. Yakkong, Hwanggumkong and Hukae contained 2491.4 $\mu$g, 2176.8 $\mu$g and 1893.5$\mu$g of isoflavone in each gram of dry matter, respectively, and existed mainly as glycoside isomers. Oligosaccharide contents were similar among the cultivars. The total concentration of phytic acid was $2.63\%$ of Hwanggumkong, $2.12\%$ of Yakkong and $2.80\%$ of Huktae.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.734-739
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• 2007

This study was conducted to observe the quality characteristics of cheonggukjang fermented with new small-seed soybeans ('Agakong') according to the degree of germination of the raw soybeans. The sprouting rate was $8.6{\pm}5.6%$ after 12 hr of germination, but at 24 hr it increased rapidly to $85.4{\pm}4.7%$. We confirmed that the total isoflavone content immediately after soaking was 273.9 mg%, which was at least 3 times greater than for common soybeans; content increased at the start of germination, and increased to 338.4 mg% by 24 hr of germination, but then decreased. The quantity of viscous substance of the cheonggukjang increased in proportion to the degree of germination of the raw soybeans. The levels of amino acids in the cheonggukjang made from non-germinated soybeans, and soybeans germinated 48 hr, were 12.45 and 10.06%, respectively. The isoflavone levels in the cheonggukjang were determined by the degree of germination of the raw soybeans. There were no significant differences between the odor, sweet taste, savory taste, bitter taste, and overall acceptability of the cheonggukjang with different germination times of 0 to 36 hr.

• Journal of Nutrition and Health
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• v.38 no.5
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• pp.373-379
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• 2005

This study was performed to determine the effect of isoflavone on bone mineral density and bone mineral content in growing male rats. Twenty male, Sprague-Dawley rats were assigned to groups, that underwent 9 weeks of experi-ental treatment. Animals were assigned to one of two diet groups (casein group or casein supplemented with isoflavones). During 9 week of the study, food consumption was determined every other day through the measurement of total food given subtracting the food uneaten from original amount given. Rats in two experimental groups had similar initial body weights. At the end of experiment, however, the casein group had significantly greater body weights compared to casein supplemented with isoflavones group. It was also observed that the casein group had greater food intake comared to casein supplemented with isoflavones group. The difference in the final body weights of the groups was therefore due to difference in amount of food ingested, but could be due to the effect of isoflavones. Total BMD, spine BMD, and spine BMC per weight and femoral BMD per weight were significantly greater in casein supplemented with isolaones group than casein group. ALP and osteocalcin were significantly greater in the casein-fed group. Crosslink value was significantly lower in the casein supplemented with isoflavones group, All other variables were statistically similar between two groups. Overall, it can be concluded that casein supplemented with isoflavones beneficial for acquisition of bone mineral density and content on growing male rats.

• Journal of Nutrition and Health
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• v.36 no.8
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• pp.841-850
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• 2003

Soy-based formula has been used for centuries in Korea. Soybeans contain phytochemicals with a biochemically active component, isoflavone. Isoflavone is a kind of phytoestrogens, structurally and functionally similar to estrogen. This study was conducted to investigate the effects of soy-based infant formula on growth, development, and isoflavone concentration in the plasma and urine. Thirty-nine healthy infants who were delivered at K university medical center were recruited. Experimental groups were the breast milk group (n = 15, BM) who were fed breast milk, soy-based formula group (n = 10, SBF) who were fed soy-based infant formula, and the casein-based formula group (n = 14, CBF) who were fed casein-based infant formula for 4 months. HPLC analysis was used to measure the concentration of isoflavones. The measurements of infant weight, length, head circumference and chest circumference were all in the normal growth range and were similar among the experimental groups. No significant differences were found in the scores of total mean of infant development test (Development Quotient, DQ) among the experimental groups. The isoflavone content of soy-based formula was significantly higher than. that of breast milk and casein-based formula. Plasma concentration of daidzein and genistein in the infants fed soy-based formula (daidzein : 264.1 ng/ml, genistein : 392.1 ng/ml) was significantly higher (p<.0001) than that in infants fed breast milk (daidzein : 3.4 ng/ml, genistein : 3.8 ng/ml) and casein-based formula (daidzein: 8.1 ng/ml, genistein: 9.3 ng/ml). Also, urinary daidzein and genistein concentrations in infants fed soy-based formula (daidzein: 19.82 $\mu$g/ml, genistein : 17.89 $\mu$g/ml) were significantly higher (p<.001) than those in infants fed breast milk (daidzein: 0.28 $\mu$g/ml, genistein : 0.22 $\mu$g/ml) and casein-based formula (daidzein : 0.45 $\mu$g/ml, genistein : 0.33 $\mu$g/ml).