• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.502-504
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• 2009

• Journal of Plant Biology
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• v.37 no.4
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• pp.411-415
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• 1994

In immature seeds of Phaseolus vulgaris, the presence of threee new 2-deoxy type brassinosteroids (trihydroxybrassinosteroids) have been demonstrated. These less polar brassinosteroids have been demonstrated. These less polar brassinosteroids have been tentatively characterized to be (3ξ, 22ξ, 23ξ)-2-deoxy-25-methylodolicholide, (3ξ, 22ξ, 23ξ)-2-deoxoy-dolichosterone and (3ξ, 22ξ, 23ξ)-2-deoxy-24-ethylbrassinone by analysis of gas chromatography-mass spectrometry. Their less biological activity and oxidation state than those of tetrahydroxybrassinosteroids suggest that they are potent biosynthetic precusors of tetrahydroxybrassinosteroids.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.259-262
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• 2013

• Journal of Plant Biotechnology
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• v.32 no.1
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• pp.63-71
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• 2005

A cell-free enzyme solution prepared from suspension cultured cells of Phaseolus vulgaris successfully mediated conversions of cholesterol $\to$ cholestanol and 6-deoxo-28-norteasterone $\leftrightarrow$ 6-deoxo-28-nor-3-dehydroteasterone $\leftrightarrow$ 6-deoxo-28-nortyphasterol $\to$ 6-deoxo-28-norcastasterone $\to$ 28-norcastasterone. Al-though conversion of cholestanol to 6-deoxo-28-norteasterone intermediated by 6-deoxo-28-norcathasterone was not demonstrated, this strongly suggests that a complete set of biosynthetic enzymes catalyzing reactions from cholesterol to 28-norcastasterone via 6-deoxo-28-nor type brassinosteroids is endogenously present in the cells, which demonstrates that a $C_{27}$ brassinosteroids biosynthetic pathway, namely the late C-6 oxidation for $C_{27}$ brassinosteroids, is operative in the cells. Additionally, the enzyme solution mediated conversion of 28-norcastasterone to castasterone in the presence of S-adenosyl-methionine and NADPH, providing that the $C_{27}$ brassinosteroids biosynthesis is an important route to generate castasterone in the cells. Together with our previous finding that castasterone can be biosynthesized by the same biosynthetic pathway in tomato, this study demonstrates that the $C_{27}$ brassinosteroids biosynthesis is a common alternative process to maintain endo-genous level of castasterone, an active $C_{28}$ brassinosteroid, in plants.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.360-365
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• 1996

To investigate the presence of brassinosteroids in rice bran and pㅐlished rice, they were extracted with MeOH. The extracts were purified through sequential procedure of solvent fractionation, silica gel adsorption chromatography, Sephadex LH-20 column chromatography and charcoal adsorption chromatography. The activity of brassinosteroids was monitored by the rice inclination test and its presence was confirmed in each purification step. The purified active components were further separated by TLC and HPLC. Brassinosteroids in active fractions of rice bran were identified as castasterone and teasterone by HPLC. We acknowledge that our work is probably the first report of brassinosteroids in mature seeds of rice The more amount of brassinosteroids was confirmed in rice bran than polished rice. The contents of castasterone and teasterone which were identified in rice bran were 0.15 ng/g and 0.37 ng/g, respectively.

• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1117-1118
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• 2006

• Journal of Plant Biotechnology
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• v.5 no.1
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• pp.69-77
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• 2003

Brassinosteroids are known to promote cell elongation in a wide range of plant species but their effect on cell division has not been extensively studied. The effect of brassinolide on the kinetics and final division frequencies of regenerating petal protoplasts of Petunia hybrida Vilm v. Comanche was examined. Under optimal auxin and cytokinin conditions, 10-100 nM brassinolide not only reduced the time of first cell division by 4.5 days but also altered the final division frequencies after 10 days of culture. One micromolar brassinolide showed the same acceleration of first cell division but inhibited the final division frequency by approximately 9%. Under sub-optimal auxin conditions, 10-100 nM brassinolide accelerated the first cell division, but no significant increase in the 8-10 days final division frequencies. Isolated protoplasts may provide a useful model system for the investigation of the molecular mechanisms of brassinosteroid action on cell division and proliferation in higher plants.

• Journal of Plant Biotechnology
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• v.5 no.1
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• pp.63-67
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• 2003

Brassinosteroids are known to promote cell elongation in a wide range of plant species but their effect on cell division has not been extensively studied. The effect of brassinolide on the kinetics and final division frequencies of regenerating petal protoplasts of Petunia hybrida Vilm v. Comanche was examined. Under optimal auxin and cytokinin conditions, 10-100 nM brassinolide not only reduced the time of first cell division by 4.5 days but also altered the final division frequencies after 10 days of culture. One micromolar brassinolide showed the same acceleration of first cell division but inhibited the final division frequency by approximately 9%. Under sub-optimal auxin conditions, 10-100 nM brassinolide accelerated the first cell division, but no significant increase in the 8-10 days final division frequencies. Isolated protoplasts may provide a useful model system for the investigation of the molecular mechanisms of brassinosteroid action on cell division and proliferation in higher plants.

• Applied Biological Chemistry
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• v.38 no.2
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• pp.179-183
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• 1995

The brassinosteroid-like active principles from immature seeds of Zea mays were purified and identified as castasterone, teasterone, 28-norcastasterone and 6-deoxocastasterone by GC-MS analysis. Our work is probably the first report that showed the presence of brassinosteroids in Zea mays seeds.

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.293-294
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• 2009