In vitro antifungal activities of saffron (Crocus sativus L.) stigmas against Aspergillus species and toxin production

This study was carried out to evaluate the in vitro use of Croccus sativus L. (saffron) stigmas in the control of Aspergillus species which is a notable causative agent of food rot and mycotoxins. Antifungal activities of saffron stigmas and toxin production were tested against Aspergillus niger, Aspergillus flavus and Aspergillus parasiticus in vitro. Saffron dried stigmas (0, 5, 10 mg ml-1) were added in Yeast Extract Sucrose (YES) medium and dry weight of the mycelium was measured after 0, 5, 10, 15, 20, 25 and 30 days after inoculation. Colorimetric procedure was used for safranal content in tested saffron and thin layer chromatography for aflatoxin B1 (AFB1) determination. Results indicated that the amounts of crocin, picrocrocin and safranal in saffron sample were 231±0.52, 87.16±0.85 and 34.86±0.25 mg. g-1 dw, respectively. When saffron was added at concentration of 10 mg·ml-1 to YES inoculated with Aspergillus species, mycelium growth decreased by 29-32% compared to control cultures without saffron addition. Conclusively when saffron was added to YES inoculated, AFB1 production decreased from 5µg·ml-1 to not detectable level compared to control cultures without saffron addition. The growth and AFB1 reduction were not significantly different betweenAspergillus species. The results suggest that saffron can be used in pharmaceutical and food formulations to inhibit Aspergillus species and toxin production.