• 한국식품조리과학회지
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• 제26권2호
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• pp.214-219
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• 2010

In this study, phytoestrogen for the industrial production of soybean probiotics by lactic acid bacteria (LAB) was studied in a soybean extract. Soybean was fermented with LAB, Lactobacillus plantarum KCTC 3108 and Bifidobacterum longum ATCC 15707. The change in the content of various isoflavones (aglycone and glucoside) and the $\beta$-glucosidase activity in soybean during fermentation were investigated and shown to be dependent on the starter organism. Soybean extract powder fermented with L. plantarum showed the highest $\beta$-glucosidase activity and the greatest increase in the aglycone content. After 48h of fermentation, the contents of daidzin, genistin and glycitin in L. plantarum decreased from a mean initial levels of $83.03{\pm}2.17$, $168.13{\pm}8.17$ and $20.02{\pm}1.07$, respectively, to mean levels of $5.34{\pm}3.24$, $3.79{\pm}0.57$ and $1.87{\pm}1.09\;mg$/100 g. Whereas, after 48h fermentation, the contents of daidzein, genistein and glycitein increased from a mean initial levels of $8.09{\pm}0.78$, $11.20{\pm}0.84$ and $4.71{\pm}0.46$, respectively, to mean levels of $85.76{\pm}0.84$, $175.87{\pm}2.21$ and $22.41{\pm}0.91\;mg$/100 g. Taken together, these results suggested an increase of aglycones and decrease of glucoside in isoflavones occurred during fermentation, which coincided with an increase of $\beta$-glucosidase activity in the fermented soybean extract powder.

• Food Science and Biotechnology
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• 제18권2호
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• pp.463-470
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• 2009

Sixteen antioxidative active compounds isolated from the EtOAc layer of MeOH extracts of kochujang, Korean fermented red pepper paste, were structurally elucidated as fumaric acid, methyl succinate, succinic acid furan-2-yl ester methyl ester (gochujangate, a novel compound), 2-hydroxy-3-phenylpropanoic acid, 3,4-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 6,7-dihydroxy-2H-chromen-2-one (esculetin), caffeic acid, cis-p-coumaric acid, trans-p-coumaric acid, daidzin, genistin, apigenin 7-O-$\beta$-D-apiofuranosyl($1{\rightarrow}2$)-$\beta$-D-glucopyranoside, apigenin 7-O-$\beta$-Dglucopyranoside, and quercetin 3-O-$\alpha$-L-rhamnopyranoside by mass spectrometry (MS) and nuclear magnetic resonance (NMR) experiments. These compounds were analyzed for the first time as antioxidants from kochujang.

• 한국식품조리과학회지
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• 제32권2호
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• pp.197-203
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• 2016

Purpose: In this study, small black beans (Rhynchosia nulubilis) that were produced in the Jungsun province of South Korea were selected for use in various cooking recipes because they are known to contain higher isoflavones and excellent antioxidant effects, as compared to any other domestic soybeans. Methods: Physicochemical and antioxidant characteristics of small black beans were analyzed with uncooked beans and four other cooking methods of pan broiling, boiling, steaming, and pressure cooking. Results: Contents of ${\beta}$-glucosides (daidzin, glycitin, and genistin) and aglycone (daidzein, glycitein, and genistein) in small black beans were significantly different depending on the cooking methods (p<0.001). The results of the experiment indicated that the amount of total polyphenol in pressure cooked beans was highest, showing a value of 7.16 mg/g (p<0.001). Most contents of isoflavones (${\beta}$-glucoside, aglycone) in uncooked beans appeared to increase after cooking. In particular, the amount of glycitein was highest in pan broiled beans ($9.63{\mu}g/g$). The total isoflavone content differed among the different cooking methods, ranging from highest to lowest in the following order : pan broiled beans ($759.49{\mu}g/g$), pressure cooked beans ($725.12{\mu}g/g$), boiled beans ($591.05{\mu}g/g$), steamed beans ($511.61{\mu}g/g$), and uncooked beans ($180.80{\mu}g/g$) (p<0.001). Conclusion: Especially, the amount of isoflavones increased significantly in pan broiled beans and pressure cooked beans, suggestive of optimized cooking methods for increasing nutritional and functional contents in cooked food.

• 한국환경보건학회지
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• 제33권3호
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• pp.195-201
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• 2007

The objective of present study was to examine the composition of functional components (isoflavones, phytic acid, and saponin) in hypocotyls and cotyledons of six traditional Korean soybeans, namely Cheongtae, Seoritae, Jinjoori, Subaktae, Yutae, and Huktae. Three 'family' of isoflavones, as four chemical structures were present in hypocotyls and cotyledons of six soybean cultivars: the aglycones genistein, daidzein, and glycitein; the glycosides genistin, daidzin, and glycitin; the acetylglycosides 6"-O-acetylgenistin, 6"-O-acetyldaidzin, and 6"-O-acetylglycitin; and the malonylglycosides 6"-O-malonylgenistin, 6"-O-malonyldaidzin, and 6"-O-malonylglycitin. Isoflavone contents of hypocotyls and cotyledons differed among the cultivars, and glucosides and malonylglucosides accounted for more than 90% of the total phytoestrogens, with the remaining $1\sim7%$ taken up by aglycones. Concentrations of isoflavones in cotyledons were approximately about $10\sim20%$ of respective hypocotyls. Contents of phytic acids in hypocotyls and cotyledons of the selected soybean cultivars were $1.21\sim1.70%$ and $2.59\sim3.01%$, respectively. Hypocotyls of Seoritae showed the lowest content of phytic acid with 1.21%, while cotyledons of Cheongtae showed the highest content with 3.01%. The sapogenol concentrations ranged from $13.58mg/100g\sim20.82mg/100g$ for hypocotyls and $0.95mg/100g\sim2.55mg/100g$ for cotyledons showing that concentrations of saponin are $7\sim10$ times higher in hypocotyls than in cotyledons of respective soybeans. For both hypocotyls and cotyledons the sapogenol A were present in higher concentrations than soyasapogenol B.

• 한국식품영양학회지
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• 제27권1호
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• pp.10-21
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• 2014

This study is conducted to investigate the effects of Chinese artichoke powder on the antioxidant activities and the quality characteristics of tofu. Tofus are being prepared with different amounts of Chinese artichoke powder in ratios of 0, 0.2, 0.4, 0.6 and 0.8% according to the soy milk quantity. According to the increasing contents of Chinese artichoke powder, the yield and turbidity of tofus are significantly increased (p<0.001) whereas the pH levels of tofus are significantly decreased (p<0.001). In terms of color, the L, a and b values are significantly decreased with increasing Chinese artichoke powder concentrations (p<0.001). From the texture profile analysis of the tofus, the chewiness, gumminess and cohesiveness of tofus are significantly decreased (p>0.01) according to the levels of added Chinese artichoke powder content. The contents of isoflavones such as daidzin and genistin are significantly increased with increasing concentrations of Chinese artichoke powder (p<0.001). The microstructure of tofus is being examined by SEM (Scanning Electron Microscope). In the sensory test, the sample which contains 0.4% of Chinese artichoke powder is ranked significantly higher (p>0.001) than the other groups according to several sensory parameters such as appearance, color, flavor, taste, texture and the overall preferences.

• 한국식품과학회지
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• 제30권4호
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• pp.745-750
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• 1998

대두에 함유되어 있는 이소플라본은 항암, 골다공증 예방과 같은 기능을 수행하는 유용 생리활성물질이다. 국내의 주요 대두 가공 식품은 두부, 콩나물, 두유와 같은 비발효 식품과 간장, 된장, 청국장, 춘장과 같은 발효식품이 있다. 비발효 식품에서는 대두와 마찬가지로 대부분 배당체 형태로 존재하였다. 두유에는 평균 676 mg/kg의 이소플라본이 존재하였고, 두부는 종류에 따라 차이가 있었으며, 평균 1,151 mg/kg이 존재하였다. 콩나물에는 약 424 mg/kg이 존재하였다. 발효 식품 중에는 청국장(920 mg/kg)과 된장(627 mg/kg)에 많은 양의 이소플라본이 함유되어 있으며, 춘장에도 상당량이 존재하지만 간장에는 매우 적은 양이 함유되어 있었다. 또한 많은 양의 이소플라본이 aglycone의 형태로 존재하였다. 따라서 국내 전통 발효 식품인 청국장과 된장은 생체 이용성이 우수한 형태인 이소플라본 aglycone의 좋은 공급원이라고 할 수 있다.

• Food Science and Biotechnology
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• 제15권4호
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• pp.643-646
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• 2006

Cheonggukjang, a popular Korean traditional fermented soyfood, was manufactured by fermenting steamed soybeans in a temperature-controlled room by traditional methods in which steamed soy was exposed to rice straw naturally rich in Bacillus species. B. subtilus and B. licheniformis were found to be the major microorganisms present in cheonggukjang made by the traditional method. We analyzed the composition of 12 kinds of isoflavones and their glycosides present in cheonggukjang collected at various fermentation times. Total isoflavone content in raw soybeans was 2,867 mg/kg and this decreased by about 50% during cooking prior to cheonggukjang preparation. However, total isoflavone content changed slightly during 45 hr of fermentation. Total content of isoflavone glycosides, consisting mainly of daidzin, glycitein, and genistin, decreased by about 40% during 45 hr of fermenting cooked soybeans. The contents of tree isoflavones including daidzein, glycitein, and genistein showed a dramatic increase during fermentation in cheonggukjang preparation, with a 2.9-, 54.0-, and 20.6-fold increase in concentration, respectively, by the end of fermentation (45 hr). In conclusion, short-term fermentation of cooked soybeans with Bacillus species caused conspicuous changes in the composition of isoflavone derivatives, and its implication in terms of health benefits deserves further study.

• Food Science and Biotechnology
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• 제14권3호
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• pp.399-404
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• 2005

The aim of this study was to investigate the in vitro antioxidant profiles of genistein and other isoflavonoids. The reactivity of genistein towards stable radical and reactive oxygen species including ${\bullet}\;ABTS^+$, ${\bullet}{O_2}^-$, $H_2O_2$ and HOCl has been investigated, and the effects were compared with other isoflavonoids and antioxidants. All the tested isoflavonoids showed remarkable ${\bullet}\;ABTS^+$ scavenging activity and genistein was more potent than BHT and ascorbic acid. Genistein was more effective in scavenging hypochlorous acid than superoxide and hydrogen peroxide. At $10\;{\mu}M$ concentrations of genistein and genistin showed about 90% inhibitory effect on HOCl, while BHT and ascorbic acid showed lower than 50% inhibitory effect. Moreover, genistein could inhibit plasmid DNA cleavage, protein degradation and cell death from HOCl attack, while daidzein, BHT and ascorbic acid could not protect them effectively. These results suggest that genistein is a more potent radical scavenger than other isoflavonoids, and it can remarkably reduce cellular damage induced by HOCl.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 춘계학술대회
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• pp.96-96
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• 2020

Soybean seeds are important sources of non-nutritive health promoting metabolites. The contents of these metabolites are affected by both genetic and environmental factors. In the present study, the contents of five common isoflavones including daidzin, genistin, glycitin, malonyldaidzin, and malonylgenistin were analyzed in 72 soybeans of different seed coat colors, diversity, and of different origins including China (22), Japan (9), USA (12), India (4), and Korea (25). The average total isoflavone content (TIC) was maximum in Indian soybeans (3302.36 ㎍/g) and minimum in Chinese landraces (1214.95 ㎍/g). The Korean landraces had higher average TIC (2148.05 ㎍/g) than the USA genetic materials (1580.23 ㎍/g) and Japanese landraces (1485.99 ㎍/g). The content of malonylgenistin was in the range of 54.31 - 2385.68 ㎍/g in the entire population, and was the most abundant isoflavone irrespective of origin although there was content variation among individual soybeans. Besides, glycitin was the least concentrated isoflavone, and its content ranged from 0.00 to 79.79 ㎍/g. With respect to seed coat color, green soybeans from all countries displayed the maximum malonylgenistin and TIC contents. Exceptions were those of Korean and Indian origins where black and yellowish-green soybeans presented the highest malonylgenistin and TIC contents, respectively. In multivariate analysis, 92.72% of the variance was explained by the first two principal components, and the soybeans were grouped in to three clusters based on isoflavone contents. Overall, our findings signify the importance of seed coat color and origin as discriminant parameters, and provide wide spectrum of routes for breeding soybean cultivars.

• 한국미생물·생명공학회지
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• 제37권2호
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• pp.99-104
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• 2009

Streptomyces coelicolor A3(2)의 $\beta$-glucosidase 유전자를 분리하여 대장균에서 발현하여 특성을 조사하였다. 최적 활성을 나타내는 온도는 pH 5에서는 $20^{\circ}C$, pH 6에서는 $60^{\circ}C$에서 높은 활성을 나타냈다. pH에 따른 활성은 pH 3 이하와 pH 9 이상의 범위에서는 낮은 활성을 나타냈으며 pH 7에서 가장 높은 활성을 나타냈다. $\alpha$-pNPG($\rho$-nitrophenyl-$\alpha$-D-glucopyranoside), $\beta$-pNPG ($\rho$-nitrophenyl-$\beta$-D-glucopyranoside), $\beta$-pNPF($\\rho$-nitrophenyl-$\beta$-D-fucopyranoside)는 pH 3-10까지 비슷한 활성을 나타냈으며, $\alpha$-pNPG가 pH 7에서 다소 높은 활성을 보였다. $\beta$-pNPGA는 pH 5-9까지 높은 활성을 나타냈으며, 특히 pH 9에서 3배 이상의 높은 활성을 나타냈다. 기질 $\alpha$-pNPG, $\beta$-pNPG, $\beta$-pNPF의 온도에 따른 활성변화는 $\beta$-pNPF의 활성이 $60^{\circ}C$에서 증가하였고, $\beta$-pNPGA는 $30-50^{\circ}C$까지 활성이 증가하여 $50^{\circ}C$에서 최대활성을 나타내었다. 당화 flavonoid를 이용한 기질특이성의 상대활성은 daidzin, glycitin, genistin, 순으로 나타났으며 esculin과 apigenin-7-glucose는 기질로 사용하지 않았다. $\beta$-Glucosidase 활성은 EDTA, DTT에 의해 억제되었으며, $MnSO_4$, $CaCl_2$, KCl, $MgSO_4$에 의해 증가하였고, 특히 Mn이온에 의해 증가하였다. $CuSO_4$, NaCl에 의해 효소활성이 저해되었으며, 특히 $ZnSO_4$의 경우 효소활성이 강하게 억제되었다.