• 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.

• Journal of Microbiology and Biotechnology
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• v.20 no.11
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• pp.1546-1554
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• 2010

A bacterial strain capable of producing extracellular ${\alpha}$-galactosidase was isolated from a sample of sugarcane industrial waste. Microbiological, physiological, and biochemical studies revealed that the isolate belonged to Bacillus sp. Furthermore, based on a 16S rDNA sequence analysis, the new isolate was identified as Bacillus megaterium VHM1. The production of ${\alpha}$-galactosidase was optimized based on various physical culture conditions. Guar gum and yeast extract acted as the best carbon and nitrogen sources, respectively. The optimum pH was 7.5 and the enzyme remained stable over a pH range of 5-9. The enzyme was optimally active at $55^{\circ}C$ and thermostable with a half-life of 120 min, yet lost 90% of its residual activity within 120 min at $60^{\circ}C$. One mM concentrations of $Ag^2$, $Cu^2$, and $Hg^{2+}$ strongly inhibited the ${\alpha}$-galactosidase, whereas the metal ions $Fe^2$, $Mn^{2+}$, and $Mg^{2+}$ had no effect on the ${\alpha}$-galactosidase activity, and $Zn^{2+}$, $Ni^{2+}$, and $Ca^{2+}$ reduced the enzyme activity slightly. When treated with the B. megaterium VHM1 enzyme, the flatulence-causing sugars in soymilk were completely hydrolyzed within 1.5 h.

• Molecules and Cells
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• v.39 no.6
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• pp.477-483
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• 2016

Heat shock factors (Hsfs) are central regulators of abiotic stress responses, especially heat stress responses, in plants. In the current study, we characterized the activity of the Hsf gene HsfA3 in Arabidopsis under oxidative stress conditions. HsfA3 transcription in seedlings was induced by reactive oxygen species (ROS), exogenous hydrogen peroxide ($H_2O_2$), and an endogenous $H_2O_2$ propagator, 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB). HsfA3-overexpressing transgenic plants exhibited increased oxidative stress tolerance compared to untransformed wild-type plants (WT), as revealed by changes in fresh weight, chlorophyll fluorescence, and ion leakage under light conditions. The expression of several genes encoding galactinol synthase (GolS), a key enzyme in the biosynthesis of raffinose family oligosaccharides (RFOs), which function as antioxidants in plant cells, was induced in HsfA3 overexpressors. In addition, galactinol levels were higher in HsfA3 overexpressors than in WT under unstressed conditions. In transient transactivation assays using Arabidopsis leaf protoplasts, HsfA3 activated the transcription of a reporter gene driven by the GolS1 or GolS2 promoter. Electrophoretic mobility shift assays showed that GolS1 and GolS2 are directly regulated by HsfA3. Taken together, these findings provide evidence that GolS1 and GolS2 are directly regulated by HsfA3 and that GolS enzymes play an important role in improving oxidative stress tolerance by increasing galactinol biosynthesis in Arabidopsis.