• Microbiology and Biotechnology Letters
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• v.13 no.1
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• pp.13-17
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• 1985

Rhizobium japonicum isolates from all around Korea could be classified into two groups, i.e., acid producing fast-growers with 2.4 hour mean generation time and non-acid producing slow-growers in yeast extract-mannitol medium with 13.1 hour mean generation time. Tested fast-growers were higher in 6-phosphogluconate dehydrogenase activity than slow-growers were and used sucrose as carbon source whereas slow-growers did not. Fast-grower R4, R257, R278, showed tolerance even in 0.5M NaCl or above and the growth of all the strains tested were inhibited at below pH 4.5. Relative symbiotic activities of nitrogen fixation for these isolated with Glycine max cv. Jangyeobkong (commercial soybean cultivar mostly cultivated in Korea) ranged 0.1 to 2.0 comparing to that of R. japonicum L-259 (NRRL), without regard to their growth rate.

• Journal of Applied Biological Chemistry
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• v.50 no.2
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• pp.63-69
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• 2007

Compositional components such as isoflavone, protein, oil, fatty acid, and free sugar in Korean vegetable soybeans were examined with four cultivars including Hwaeomputkong, Keunolkong, Mirang, and Danmi 2. In the isoflavone, Mirang cultivar showed the highest content ($967.1{\mu}g/g$), whereas Keunolkong was the lowest content ($535.9{\mu}g/g$). The malonylglucosides were the predominant isoflavone type followed by the glucoside, aglycone, and acetyl glucoside forms, respectively. In the protein content, Hwaeomputkong was the lowest (41.7%) and Danmi 2 was the highest (45.9%). The oil contents were 11.5 to 21.2% and Mirang cultivar was the lowest. The fatty acid compositions of the oil extracts exhibited that linoleic acid was the highest (33.6-42.5%), followed by oleic, palmitic, linolenic, and stearic acids. Whereas, oleic acid ($46.7{\pm}2.0%$) was more than linoleic acid ($33.6{\pm}1.3%$) in Mirang cultivar. In the free sugar contents, Hwaeomputkong cultivar showed the highest level and sucrose ($5.52{\pm}0.49%$) appeared to be most prevalent in vegetable soybeans.

• The Korean Journal of Pesticide Science
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• v.11 no.1
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• pp.52-58
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• 2007

ALA (5-aminolevulinic acid) has been proposed as a tetrapyrrole-dependent photodynamic herbicide and insecticide by the action of the protoporphyrinogen IX oxidase (Protox IX). The present study was conducted to determine growth responses of plant and insects to ALA, biodegradable biopesticidal substance. In the paddy condition experiment, plant height and shoot fresh weight of barnyardgrass (Echinochloa crus-galli) was more reduced by ALA than rice plants, even though both plant species show great phytotoxicity. Hairy crabgrass (Digitaria sanguinalis), a monocot weed, was more sensitive to ALA at 5mM under upland condition when ALA applied on the foliage, compared with soybean (Glycine max) as a dicot crop. ALA solutions were tested for their insecticidal and larvicidal activities against Spodaptera exigua (Hubner) and Tetranychus urticae Koch. by foliar application and leaf-dipping method. The result showed higher insecticidal activity of ALA at 10mM and its mixture with insecticide luferon against S. exigua. Strongest insecticidal activity against T. urticae was observed from the ALA solution at 10mM 72 days after application. This results show that ALA solution had potent herbicidal and insecticidal activities against agricultural pests even though their activities were lower than those of synthetic pesticides.

• Fisheries and Aquatic Sciences
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• v.12 no.1
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• pp.1-5
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• 2009

Crude saponin, extracted from the starfish Asterias amurensis, was assessed for its capacity as a biological pesticide. As part of this analysis, its insecticidal and repellent activities, in addition to its acute and chronic toxicities were tested. In comparison with the control group, insecticidal activity of saponin against tobacco cutworm, Spodoptera litura, in kale, Brassica loeracea was low at 36.4%. Repellent activities of the extracted saponin against green peach aphid, Myzus persicae, and S. litura, on soybean leaf, Glycine max and kale were 65.6% and 35.0% at $1^{st}$ day, and 54.5% and 30.0% at $3^{rd}$ day, respectively. Acute and chronic toxicity analysis was carried out using acute immobilizatioin test and reproduction impairment test, respectively. The saponin had 48 h-$EC_{50}$ of $65.21{\mu}g/mL$. Twenty-one day accumulative reproduction after treatment was lower in Daphnia magna at $7{\mu}g/mL$ saponin (78 youngs), compared with the control group (129 youngs). These results indicate that the extracted saponin exhibited some toxicity and has potential as a repellent against insects.

• Biomolecules & Therapeutics
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• v.27 no.4
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• pp.363-372
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• 2019

Daidzein isolated from soybean (Glycine max) has been widely studied for its antioxidant and anti-inflammatory activities. However, the protective effects of 7,8,4'-trihydroxyisoflavone (THIF), a major metabolite of daidzein, on 6-hydroxydopamine (OHDA)-induced neurotoxicity are not well understood. In the current study, 7,8,4'-THIF significantly inhibited neuronal cell death and lactate dehydrogenase (LDH) release induced by 6-OHDA in SH-SY5Y cells, which were used as an in vitro model of Parkinson's disease (PD). Moreover, pretreatment with 7,8,4'-THIF significantly increased the levels of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) and decreased malondialdehyde (MDA) activity in 6-OHDA-induced SH-SY5Y cells. In addition, 7,8,4'-THIF significantly recovered 6-OHDA-induced cleaved caspase-3, cleaved caspase-9, cleaved poly-ADP-ribose polymerase (PARP), increased Bax, and decreased Bcl-2 levels. Additionally, 7,8,4'-THIF significantly restored the expression levels of phosphorylated c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase 1/2 (ERK 1/2), phosphatidylinositol 3-kinases (PI3K)/Akt, and glycogen synthase kinase-3 beta ($GSK-3{\beta}$) in 6-OHDA-induced SH-SY5Y cells. Further, 7,8,4'-THIF significantly increased the reduced tyrosine hydroxylase (TH) level induced by 6-OHDA in SH-SY5Y cells. Collectively, these results suggest that 7,8,4'-THIF protects against 6-OHDA-induced neuronal cell death in cellular PD models. Also, these effects are mediated partly by inhibiting activation of the MAPK and PI3K/Akt/$GSK-3{\beta}$ pathways.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.11
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• pp.1700-1707
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• 2015

The effects of drying temperature on drying characteristics of soybeans with different grain sizes [6.0 (S), 7.5 (M), and 9.0 mm (L) (${\pm}0.2$)] with 25.0% (${\pm}0.8$) initial moisture content were studied. Drying temperatures varied at 25, 35, and $45^{\circ}C$, with a constant air velocity (13.2 m/s). Thin-layer drying models were applied to describe the drying process of soybeans. The Midilli-Kucuk model showed the best fit ($R^2$ >0.99). Based on the model parameters, drying time to achieve the target moisture content (10%) was successfully estimated. Drying time was strongly dependent on the size of soybeans and the drying temperature. The effective moisture diffusivity ($D_{eff}$) was estimated by the diffusion model based on Fick's second law. $D_{eff}$ values increased as grain size and drying temperature increased due to the combined effect of high temperatures and high drying rates, which promote compact tissue. Deff values of S, M, and L estimated were in the range of $0.83{\times}10^{-10}$ to $1.51{\times}10^{-10}m^2/s$, $1.17{\times}10^{-10}$ to $2.17{\times}10^{-10}m^2/s$, and $1.53{\times}10^{-10}$ to $2.95{\times}10^{-10}m^2/s$, respectively, whereas activation energy ($E_a$) based on drying temperature showed no significant differences in the size of soybeans.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.332-338
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• 2012

Soil compaction is one of the major problems facing modern agriculture. Overuse of machinery, intensive cropping, short crop rotations, intensive grazing and inappropriate soil management leads to compaction. This study was carried out evaluate of the effects soil texture and different compaction levels within the soil profile on the soybean root growth and productivity. The soybean plants were grown in $21cm{\o}{\times}30cm$ cylinder pots using three different soil textures (clay, fine loamy and coarse loamy) compacted at different compaction levels (1.25, 1.50, 1.75, and 2.00 MPa). Results revealed that soybean development is more sensitive on penetration resistance, irrespective of soil type. Soybean yield and root weight density significantly decreases with increasing levels of soil compaction in both clayey and fine loamy soils, but not in coarse loamy soil. The highest root weight density was recorded in coarse loamy soils, followed by fine loamy and clay soils, in descending order. The root growth by soil compaction levels started to decline from 1.16, 1.28 and 1.60 MPa for clay, fine loamy and coarse loamy soils. Soybean production in the field experiment decreased about 30% at compacted sub-soils compared to undisturbed soils.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.319-324
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• 2014

Soybean (Glycine max (L.) Merr.) is an important crop for protein, oil, carbohydrates, isoflavones, and many other nutrients to humans and animals. But, antinutritional factors in the raw mature soybean are exist. Raffinose and stachyose are main antinutritional factors in soybean seed. Both raffinose and stachyose are carbohydrates, belonging to the raffinose family of oligosaccharides (RFOs). RFOs are not readily digested in humans and cause flatulence or diarrhea. The objective of this research is to obtain the information on raffinose and stachyose content according to genotype and environment. A total of twenty two soybean genotypes (11 cultivars, 3 germplasms and 8 breeding lines) were selected. Each genotype was grown in the field for two years with two replications and harvested in bulk at natural maturity for two years. Content of raffinose and stachyose was detected by HPLC. The raffinose content (g/kg) of 22 genotypes was $2.68{\pm}0.21-5.87{\pm}2.43$ in year 1 and was $3.24{\pm}0.37-9.05{\pm}0.16$ in year 2. The stachyose content (g/kg) was $4.23{\pm}0.98-27.68{\pm}9.90$ at year 1 and was $5.11{\pm}1.09-25.32{\pm}0.35$ in year 2. Genotype and environment have highly significant effects on raffinose and stachyose content. Three genotypes (Da-7, 116-13, and RS-78) have low stachyose content at 5% significant level in two years. A positive correlation ($R^2=0.1985^*$) between raffinose and stachyose was observed in year 2. These informations are valuable in soybean genetics and breeding program related with raffinose and stachyose content.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.3
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• pp.248-256
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• 1997

In order to establish a optimum level and proper method of fly ash application for soybean cultivation, the successive three years experiment was conducted in the field applied with four application levels of fly ash, 0, 30, 60, 90 MT/ha during the 1991 to 1993. Influence of successive application and residue of fly ash in soil on soybean growth and yield was discussed. Fly ash application had a favorable effect on soybean growth, however over application such as 90 MT/ha caused to turn the color into the brown of young leaf edge and eventually to have necrosis on the leaf. This symptom was prominent under the application of bituminous coal fly ash. In the 1st year cultivation of soybean, the highest yield was obtained at application level of 30 MT/ha. In the 2nd year, application of anthracite fly ash showed the highest yield at 60 MT/ha for successive application and at 90 MT/ha for the 1st year application followed by the 2nd year residue. Application of bituminous coal fly ash showed the highest yield at 60 MT/ha for the both successive application and residue. In the 3rd year, successive application of the both fly ash was given the highest yield at 30 MT/ha, respectively indicating the decrease of yield with increasing level of application. In case of residue plot, the highest yield by the application of anthracite fly ash was made at 90 MT/ha for the 1st year application followed by 2 years residue and at 60 MT/ha for the 1st and 2nd year application followed by the 3rd year residue. But in the residue plot of bituminous coal fly ash, yield was highest at 30 MT/ha showing the decrease of yield with increasing level of residue. Enhancement in growth and yield of soybean by application of fly ash was due to the fact that fly ash contained some plant nutrients such as phosphorus, silicon, and boron etc. and reformed soil pH that caused to increase availability of nutrients in soil.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.2
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• pp.143-148
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• 2017

Soybean [Glycine max (L.) Merr.] seed is an important dietary source of protein, oil, carbohydrates, isoflavones, and other nutrients for humans and animals. Raffinose and stachyose are the main antinutritional factors in soybean seed. They are carbohydrates belonging to the raffinose family of oligosaccharides, which are not readily digested in humans and cause flatulence or diarrhea. The genetic reduction of the raffinose and stachyose contents in mature soybean seeds will improve the nutritional value of soybean. The objective of this research was to evaluate agronomic traits with 10 $F_6$ strains selected from breeding populations derived from a cross among seven parents. The contents of raffinose and stachyose in mature seeds were detected by high-performance liquid chromatography. Agronomic traits such as flower color, flowering date, harvesting date, lodging, plant height, seed coat color, hilum color, 100 seed weight, and yield were evaluated. Ten intermediate parents showed low raffinose and stachyose contents. The intermediate parent 883-1 had a small seed size, six intermediate parents (15A1, 15D1, RS-5, RS-33, RS-64, and RS-70) had a medium seed size, and two intermediate parents (14G20 and RS-21) had a large seed size. The intermediate parent RS-21 had a black seed coat and a green cotyledon. Four intermediate parents (883-1, 14G20, RS-5, and RS-21) had elite agronomic traits. The new intermediate parents developed through this study will be used to develop improved soybean cultivars with low contents of raffinose and stachyose.