• Korean Journal of Microbiology
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• v.29 no.2
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• pp.111-116
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• 1991

Rhizopus nigricans produces 11.alpha.-hydroxyprogesternoe with a unidentified byproduct, which is hardly separated. Results of chromatography, IR and NMR spectroscopy identified the byproduct to be 11.alpha.-hydroxy-allopregnane-3,20-dione. R. nigricans was found to transform progesternoe into a monoform intermediate, 11.alpha.-hydroxyprogesterone, from which 11.alpha.-hydroxy-allopregnane-3,20-dione and 6.betha., 11.alpha. - dihydroxyprogesterone were formed respectively by 5.alpha.-reduction and 6.betha.-hydroxylation.

• Korean Journal of Microbiology
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• v.23 no.4
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• pp.297-301
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• 1985

The dependence of activities of Aspergillus phoenicis on the culture conditions in the progesterone transformation reaction was investigated. In the beginning of the reaction, $6{\beta},\;11{\alpha}-dihydroxyprogesterone$ was not produced even at high concentration of $11{\alpha}-hydroxyprogesterone$. However, large amount of the product was obtained after the complete exhaustion of progesterone. When spores of A.phoenicis replaced mycelia as enzyme source, $11{\alpha}-hydroxyprogesterone$ was produced after a considerably long indyction period, and its maximum production rate followed the exponential growth phase. The $6{\beta}-hydroxylation\;of\;11{\alpha}-hydroxyprogesterone$ continued, even after the stationary growth phase. A. phoenicis showed high enzyme activity for these reactions when the phosphate buffer solutions were used in place of the ordinary culture medium. The buffer solutions of low pH gave more yield of $11{\alpha}-hydroxyprogesterone$ than those of high pH. However, the addition of flucose to the buffer solutions did not activate the transformation reaction. The presence of progesterone seems to be necessary for the induction of enzymes for the $6{\beta}-hydroxylation\;of\;11{\alpha}-hydroxyprogesterone\;since\;6{\beta},\;11{\alpha}-dihydroxyprogesterone$ is not produced in the reaction medium containing only $11{\alpha}-hydroxyprogesterone$ as a substrate.

• The Korean Journal of Mycology
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• v.13 no.2
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• pp.83-87
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• 1985

The temperature dependency and the stability of enzyme systems for $11{\alpha}-hydroxyla­tion$ of progesterone were investigated using Aspergillus phoenicis. Though A. phoenicis conserves high enzyme activities for lactose hydrolysis even at high temperatures, the bioconversion reaction of progesterone by this strain was found to be very temperature sensitive. The compositions of reaction mediums of inside and outside of cells were analyzed using sonication technique. At early stage of reaction, the concentration of $11{\alpha}-hydroxyprogesterone$ of cell inside was higher than that of outside. But as the reaction proceeded further, the $11{\alpha}-hydroxyprogesterone$ existing inside of cells being converted into another products, its concentration was lower within the cells that in the bulk medium. Even in the reaction mediums containing organic solvents, A. phoenicis was founded to be able to metabolite, so that $11{\alpha}-hydroxyprogesterone$ can be produced continuously from fixed bed reactions packed with immobilized A phoenicis in vivo.