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Updated: Jul 30, 2026

Customization of Aspergillus niger Morphology Through Addition of Talc Micro Particles
Published on: March 15, 2012
Stereo- and regioselective hydroxylation of grindelic acid derivatives by Aspergillus niger
A A Orden1, D A Cifuente, E J Borkowski
1Intequi-Conicet. Area de Química Orgánica, Facultad de Química, Bioquímica y Farmacia, UNSL, Chacabuco y Pedernera, 5700, San Luis.
Abstract:
Stereo- and regioselective hydroxylation of grindelane derivatives on position 3beta was catalyzed by cultures of Aspergillus niger. Grindelic acid (1), methyl grindelate (2), 15-hydroxy-7(8)-en-9alpha,13(S)-oxide-ent-labdane (3) and 7alpha,8alpha-epoxymethylgrindelate (4) were bioconverted into the corresponding 3beta-hydroxy derivatives as the only biotransformation products. 13(S),15-dihydroxy-8(9)-en-ent-labdane (5) remained unreacted under the same conditions. The conformational and electronic studies of the substrates are discussed.
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