Acta Pharm. 49 (1999) 201-209

Mycological contamination of stored herbal drugs

ZDENKA CVETNIC^* and  STJEPAN PEPELJNJAK

Department of Microbiology,  Faculty of Pharmacy and Biochemistry,   University of Zagreb,  10000 Zagreb

Fungal flora was identified in 85 samples of dried herbal drugs belonging to 53 species. Moulds of the genera Aspergillus (62.3%), Rhizopus (42.3%) and Penicillium (41.1%) have been most frequently observed. Aflatoxigenicity and ochratoxigenicity detection of Aspergillus flavus and A. ochraceus strains were tested by a specific fluorescence method in long wavelength UV-light (365 nm) in aflatoxin- producing ability medium (APA). Only one out of fifteen A. flavus strains investigated showed fluorescence and was found to be aflatoxin B₁ producer. The strain was isolated from stored sample of Gentiana radix. The concentration of toxin obtained from fluorescent APA medium was 0.75 micrograms g^-1. None of three A. ochraceus strains produced ochratoxin A or aflatoxin B₁.
It is suggested that plant material intended for medical use should be stored under appropriate conditions in order to prevent growth of naturally occurring toxigenic fungi.

Keywords: mycological contamination, drug plants, aflatoxin B1