Supercritical fluid extraction of dry mouldy bran for the purification of gibberellic acid from the concomitant products produced during solid state fermentation.

Dry mouldy bran (DMB) containing gibberellic acid (GA,) is a solid fermented material resulting
from solid state fermentation by Gibberellufqjikuroi P-3. Samples of this bran were subjected
to supercritical fluid extraction (SCFE) to remove other concomitant products which are produced
during the fermentation process. A fungal sterol, identified as the major component in the
extract, was found to disturb the defensive mechanism in rice seedlings. The physicochexnical
and spectral characteristics of this sterol were established. The extraction of the sterol by SCFE
was found to improve with the use of an entrainer (ethanol). The fungal mycelia and spores
were disintegrated during the SCFE process. The solid material retained the GA, activity without
any loss during extraction and can be used directly for application on agricultural fields.