• Korean Journal of Microbiology
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• v.49 no.4
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• pp.391-397
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• 2013

Changes in ${\beta}$-glycosidase activity, total phenolic and isoflavone contents, and antioxidant activities during the fermentation of Korean black soybeans (Seoritae and Seomoktae) fermented food cheonggukjang by the potential probiotic Bacillus subtilis CSY191 were investigated. The levels of total phenolic and isoflavone-malonylglycoside and -aglycone contents increased, while 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity and ferric reducing/antioxidant power (FRAP) increased, but the isoflavone-glycoside contents decreased after cheonggukjang fermentation. The content of antioxidant compounds, including isoflavone-aglycones and -malonylglycosides, was increased by fermenting-processing, whereas the content of isoflavone-glycosides was decreased in the fermented soybeans. In particular, the Seoritae soybean fermented at 3 $7^{\circ}C$ for 48 h displayed the highest antioxidant activities, compared to those of the Seomoktae soybean and the fermented. The highest levels of daidzein, glycitein, and genistein were present at concentrations of 253.0 ${\mu}g/g$, 72.5 ${\mu}g/g$, and 114.1 ${\mu}g/g$ after 48 h of Seoritae soybean fermentation. From those results, we suggest that the high antioxidant activity of cheonggukjang of black soybeans might be related to the markedly higher levels of total phenolic and isoflavone-aglycone and -malonylglycoside contents achieved during fermentation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.1
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• pp.48-52
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• 2006

Naturally occurring soybean isoflavones are known to be influenced by various genetic and environmental conditions. Growth, yield, and isoflavone content were determined in four different cultivars of soybean grown under drained paddy and upland fields. Most of growth characteristics and yield components of four different soybean cultivars harvested in drained paddy field were greater than those in upland field, regardless of cultivar. By means of high performance liquid chromatography, total daidzein and genistein contents of soybean in drained paddy field were increased up to 40 and 35%, respectively, compared with those in drained paddy field. Besides isoflavone contents, the growth and yield of soybean were significantly affected by cultivar and field conditions, indicating the necessity of genetic program for soybean cultivars appropriate to drained paddy field conditions. In conclusion, converting paddy field into upland may effectively improve soybean cropping system, especially in terms of isoflavone increment under paddy field conditions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.160-165
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• 2006

Biofuctionality of soybean seeds and soy-bean products have been fortified by the uncovering of the multifuctional beneficial effects of isoflavones. As one way to fully utilize beneficial effects of isoflavones in soybean sprout is through the enhancement of isoflavone contents in soybean seeds, genetic selection for higher isoflavone and cultivational measures to increase isoflavone content in soybean seeds were attempted. Isoflavones (daidzein, gemstein) contents in soybean seeds and soybean sprouts were determined by high performance liquid chromatography. Total isoflavone contents in soybean seeds ranged from 756 to $1,682{\mu}g/g$ and Iksan #13 $(1,682{\mu}g/g)$ showed highest content among the 21 germplasms analyzed. Onetime treatment of soybean plants with Antipol or Piaster at the $V_4$ stage yielded seeds with higher isoflavones as $2,472{\mu}g/g\;or\;2,052{\mu}g/g$, respectively, which were higher by 37% and 14% than that of seeds in the control plants, respectively. In Eunhakong, Isoflavone contents of soybean sprout changed during sprouting. Daidzein content in hypocotyl increased to maximum on the third day of cultivation and decreased there-after, whereas the content changed little in cotyledon. In sprouts of Pungsannamulkong, daidzein content in hypocotyl showed a maximum level on the first day and decreased gradually thereafter but, the content changed little in cotyledon. Total isoflavone contents in lateral roots which developed on the 6th day after sprouting ranged from 4,416 to $5,232{\mu}g/g$ DW.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.4
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• pp.543-550
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• 2010

This study was conducted to determine the characteristics of chungkukjang with added isoflavone extracted from arrowroot and to determine its utility as a functional food substance. Crude isoflavone was prepared from arrowroot by the ethanol extraction method and frozen dried (AI). Samples of chungkukjang each had different amounts of isoflavone extracts added to them: 0 (control), 1.76 (AC1-chungkukjang), 3.52 (AC2-chungkukjang), and 7.11 (AC3-chungkukjang) g/kg. The pH, color, slime material content, calcium, and isoflavone of each sample were measured to investigate the quality and changes in isoflavone content. As AI increased, the pH of chungkukjang decreased to 7.46~7.53 compared to the pH of control (7.63). The slime material content range increased to 4.46~6.16%. However, there was no significant difference in the general components of chungkukjang between each of the groups (Con, AC1, AC2, AC3). In colors of chungkukjang, values for $L^*$, $a^*$, and $b^*$ decreased as AI increased. Meanwhile, the calcium content of AC1, AC2 and AC3 tended to increase by 11.18~12.82% compared to the control. This may be due to the influence of Ca in the arrowroot extract powder. There was a remarkable increase in total isoflavone content, by 30.81~130.66%, with an order of AC3>AC2>AC1. In all of the groups, the content of genistein and daidzein, aglycone form, increased dramatically, by 65.00~128.34%, and 89.38~142.91%, respectively, compared to the control. In AC3, in particular the genistin and daidzin content increased by 103.47% and 188.13%. These results showed that AI can be used as a source of isoflavone supplementation in chungkukjang.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.3
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• pp.239-247
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• 2018

Soybean produces three major types of isoflavones, daidzein, genistein, and glycitein aglycones and their glucosides and malonylglucosides. It has been known that malonylated glucosides are rapidly converted to their corresponding aglycones due to the unstable thermolabile glucoside malonates; therefore, the analytical study of malonylated glucosides has been insufficient. In this study, we analyzed the malonylglucoside content in soybean seeds. Isoflavone analysis of three soybean cultivars revealed that 81.5~90.0% of the total isoflavones were malonylglucosides, whereas aglycones were rarely detected. Moreover, the total isoflavone content increased during a 5-day germination period where growth regulators and coumaric acid treatments tended to yield higher isoflavone content than the normal germination treatment, however the differences were not significant; notably, the isoflavone accumulation trend continued with additional germination days. The content of malonylglucoside was higher than that of other isoflavones, which was 83.7~86.6% of the total isoflavone content in seeds with a 3-day germination period. Furthermore, isoflavones were significantly accumulated in the hypocotyl of seedlings with a 5-day germination period. The content of isoflavone in the hypocotyl of the Pungsannamul-kong was 10,240 ug/g when treated with coumaric acid, which was considerably higher than that of other cultivars and treatments. Additionally, soybean seeds heated at $60^{\circ}C$ for 1 hour produced higher isoflavone content than non-heated soybean seeds. Our results show that it is possible to increase the isoflavone content in soybean seeds through various treatments.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.498-502
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• 2005

Three Korean soybean varieties - Shinpaldal-2, Seomoktae and Seoritae - were investigated for changes in their physical properties and the amount of functional components (i.e. isoflavones and oligosaccharides), during germination. Soybeans were germinated at $20^{\circ}C$ for 96 hr in complete darkness. The dry weights of cotyledone, hypocotyl, seed coat, and hilum of Seoritae were heavier than those of other varieties. The dry weights of the three bean varieties decreased steadily in spite of root growth. The largest amount of isoflavone content was observed from Shinpaldal-2 (1.824 mg/g), followed by Seoritae (1.216 mg/g) and Seomoktae (1.125 mg/g). Total isoflavone content increased by 13% during initial germination, and then decreased thereafter. Aglycone types such as daidzein and genistein dominated the increase in isoflavone contents. The increase in genistein content of Shinpaldal-2 was 17.5 fold compared with ungerminated soybean, while the amount of daidzein was 6.7 times as much as ungerminated Shinpaldal-2 over an 18-hr germination period. Oligosaccharide contents such as raffinose (Raf) and stachyose (Sta) rapidly decreased during germination, while the sucrose (Sue) content remained constant until 36-48 hr of germination. From these results, it was clearly shown that the germination process significantly changed the contents of functional nutrients in soybeans. Therefore, the optimization of germination process should be considered to improve the biological functionality of soybeans in food processing.

• Korean journal of food and cookery science
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• v.22 no.4 s.94
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• pp.545-551
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• 2006

The effects of the addition of germinated soybean powder on Injulmi characteristics were investigated in this study. Injulmi was prepared with five different levels of germinated soybean powder (0%, 4%, 8%, 12% and 16%)and the physical properties were examined. The moisture content decreased, while the protein, fat and ash contents increased With increasing germinated soybean powder content. Total isoflavone contents, 3.39${\sim}$15.35 mg% before cooking, slightly increased to 3.94${\sim}$15.96 mg% after cooking. Genistin, genistein, daidzin and daidzein, which are blown to be the major functional isoflavones, accounted for approximately 93% of total isoflavone contents. The color of Injulmi darkened slightly and became greenish yellow with the addition of germinated soybean powder. Textural profile analysis showed that hardness and gumminess increased, but cohesiveness and springiness decreased with increasing germinated soybean powder level. Sensory test showed that Injulmi prepared with up to 8% added germinated soybean powder was evaluated as being equally acceptable as Injulmi without germinated soybean powder.

• The Korean Journal of Food And Nutrition
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• v.33 no.3
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• pp.299-308
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• 2020

This study investigated the quality characteristics of black soybean sediments to diversify the availability of soybean. The cooking method selected for black soybean sediment preparation was a pressure cooking process without soaking, considering the isoflavone content. The black soybean sediments were prepared by the addition of 0, 10, 30, 50 and 100% (w/w) black soybean. When 0% to 100% black soybean was added to the black soybean sediments, the moisture and crude protein contents increased from 53.17% to 54.41% and from 12.07% to 21.68%, respectively. The total isoflavone content of the black soybean sediments was increased from 2.69 ㎍/g to 696.09 ㎍/g, respectively, by the addition of black soybean. The anthocyanin content of the black soybean sediments ranged from 279.29 ㎍/g to 387.8 ㎍/g by the addition of black soybean. The total polyphenol content and the total flavonoid content of the black soybean sediments range from 1.72 mg/g to 2.00 mg/g and 0.89 mg/g to 0.92 mg/g, respectively, by the addition of black soybean. Given the isoflavones, total polyphenol, and anthocyanin content of the black soybean sediments, it is appropriate that the ratio of added black soybeans is at least 50% after the pressure-cooking process, regardless of soaking.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.778-782
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• 2005

Analysis of black soybeans [Glycine max (L.) Merr.; 59 Korean varieties] revealed that 100-seed weights of green cotyledon seeds (33.5 g, n=31) were higher than those of yellow ones (28.9 g, n=28). Contents of delphinidin-3-glucoside (D3G), cyanidin-3-glucoside (C3G), petunidin-3-glucoside (P3G), and total anthocyanins in seed coats of black soybeans were 0.03-4.15, 0.74-18.36, 0.02-1.60, and 0.87-23.52 mg/g, respectively, among which most prominent anthocyanin was C3G (80.9% of total content), followed by D3G (13.6%) and P3G (5.5%). No significant differences were observed in color parameters $a^*$ and $b^*$ between black soybeans with yellow cotyledon (BYC) and green cotyledon (BGC). Total isoflavone content of BGC was higher than that of BYC, and negative correlation was found between total anthocyanin and isoflavone contents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.1
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• pp.96-101
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• 2013

This study was carried out to investigate the changes in antioxidant activity, and the isoflavone and free amino acid content in fermented tofu of the ingredients of kimchi (red pepper, garlic, ginger, and anchovies) and lactic acid bacteria (Pediococcus acidilactici KL-6) during 24 weeks of fermentation at $20^{\circ}C$. The total polyphenol content of various types of fermented tofu such as the control (tofu with kimchi ingredients mixture), tofu and kimchi ingredients with lactic acid bacteria (TL), and tofu in pre-fermented kimchi ingredients with lactic acid bacteria (TPL) ranged from 156.34 to 165.17 mg/g, showing that TPL was significantly higher in terms of fermentation time (6 weeks) compared to others. The DPPH free radical scavenging activity of TPL (84.11%) was higher than that of the control (76.68%) and TL (78.95%) after 12 weeks fermentation at $20^{\circ}C$. The changes of nitrite scavenging activity and SOD-like activity in the tested tofu showed the same tendency as the DPPH free radical scavenging activity during 14 weeks fermentation TPL showed statistically significant levels of increased antioxidant activity, so we compared the isoflavone and free amino acid content. The isoflavone and free amino acid content of TPL was 2.34 mg/g and 20.81 mg/g after 14 weeks fermentation, respectively.