Objective:The documented evidence of toxigenic fungi and their toxic metabolites on medicinal plants,coupled with the ability of these toxins to resist decomposition and temperature treatments necessitated this study,with a view of surveying for a possible carry over into the final medicinal products.As such popular indigenous crude herbal preparations widely consumed for various ailments in south-western Nigeria,were screened for fungal contamination,mycoflora enumeration,flora mycotoxin productibility,detection and quantification of a potent human carcinogen(aflatoxin). Methods:Fungal contamination was assessed on acidified potato dextrose agar using the plate count method, while mycotoxin detection,extraction and quantification were achieved by the thin - layer chromatography and chemical confirmation techniques.Mycoflora were characterized by standard procedures.Results:The total plate count ranged from 1.80×10~4 CFU/ML to 1.1×10~5 CFU/ML and 2.00×10~3 CFU/ML to 1.38×10~5 CFU/ML for water and dry gin extracted preparations respectively.The mycoflora consisted of six genera(Aspergillus,Penicillium,Fusarium, Mucor,Alternaria and Rhizopus).Thirty-four percent(34%) of the potential toxigenic species(Aspergillus, Penicillium and Fusarium) produced mycotoxins in culture,while further characterization indicated production of aflatoxin Bl(42%),ochratoxin A(50%) and penicillic acid(8%) by the mycotoxigenic strains respectively. The aflatoxin content of the herbal medicines ranged between 0.004μg/kg and 0.345μg/kg.Conclusion:The study confirmed the carry over of the fungal contaminants and their toxic metabolites into the final herbal medicines in quantities that exceeded some of the available limits.The implication of this is that the chronic exposure to mycotoxins particularly aflatoxins as a result of long term consumption of these preparations,could lead to impaired growth, nutritional interference,immunologic suppression and hepatocellular carcinoma in the consumers.
