Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
69708 | Journal of Molecular Catalysis B: Enzymatic | 2015 | 9 Pages |
•Enzymatic oxidations of betulinic and betulonic acids.•Biotransformations with two bacteria and two fungi were studied.•Several di-, tri-, tetrahydroxy and multiply oxidized compounds were obtained.•Five novel compounds were produced and characterized.
Enzymatic transformation of betulinic acid by growing cells of microorganisms provided several hydroxylated and oxidized products. Bacillus megaterium SC16644 gave 7β,15α-dihydroxybetulinic acid, 7β,15α-dihydroxybetulonic acid, and a new compound 7β,15α,23-trihydroxybetulinic acid [3β,7β,15α,23-tetrahydroxy-lup-20(29)en-28-oic acid]. Another strain of B. megaterium SC6394 produced 30-oxobetulonic acid, and a mixture of 30-hydroxybetulonic acid and a new compound 7β-hydroxy-30-oxobetulonic acid [7β-hydroxy-3,30-dioxo-lup-20(29)en-28-oic acid]. Three products were obtained from the biotransformation of betulinic acid by Streptomyces fragilis SC16401: 7β-hydroxybetulonic acid, and two new compounds 2α,7β-dihydroxybetulinic acid [2α,3β,7β-trihydroxy-lup-20(29)en-28-oic acid] and 2-oxo-7β-hydroxy-betulinic acid [2-oxo-3β,7β-dihydroxy-lup-20(29)en-28-oic acid]. Cunninghamella elegans SC16025 gave 25-hydroxybetulinic acid from betulinic acid. Oxidation of betulinic acid by Aspergillus terreus SC16513 led to two A-ring fission products: 4-hydroxy-3,4-seco-lup-20(29)-en-3,28-dioic acid and 3,4-seco-lup-20(29), 4(23)-dien-3,28-dioic acid. B. megaterium SC16644 catalyzed transformation of betulonic acid provided 7β-hydroxybetulonic acid, 7β,15α-dihydroxybetulonic acid, and a new compound 7β,15α,30-trihydroxybetulonic acid [3-oxo-7β,15α,30-trihydroxy-lup-20(29)en-28-oic acid].
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