MYCOFLORA AND NATURAL OCCURRENCE OF MYCOT OXINS IN TOBACCO FROM CIGARETTES IN EGYPT

Forty-two species and 4 varieties belonging to 21 genera were collecte d from 40 tobacco samples on glucose- and cellulose-Czapek's agar at 2 8-degrees-C and 45-degrees-C. The most common mesophiles (at 28-degree s-C) in tobacco on the two types of media were: Aspergillus flavus, A. flavus var. columnaris, A. fumigatus, A. niger, Penicillium chrysogen um and P. funiculosum. Two samples were heavily contaminated with memb ers of Fusarium (F. moniliforme, F. oxysporum, F. solani). Some fungi were encountered only on plates of cellulose agar as Chaetomium globos um, Stachybotrys atra var. microspora and S. chartarum. At 45-degrees- C the most prevalent fungus was A. fumigatus. Truely thermophiles were also collected: Humicola grisea var. thermoidae, Rhizomucor pusillus and Thermoascus aurantiacus. Based on biological assays (brine shrimp larvae (Artemia salina L.) and Bacillus megatherium test) and chemical analysis of chloroform extraction of tobacco (TLC and UV spectrophoto metric), four samples (out of 40) had toxicity and four compounds of m ycotoxins were detected namely; aflatoxins B1 & B2 (2 samples; 15.5 an d 20.7 mug/kg), zearalenone (1 sample, 5.5 mug) and T-2 toxin (1 sampl e, 2.8 mug). For studying the tracing of aflatoxins in smoking cigaret tes, three doses (10, 20 and 50 mug) of aflatoxins B1 and B2 (w/w, 1 : 1) were injected each in ten cigarettes. All extracts of cigarettes s moke proved to be non-toxic and mycotoxins not detected. However, afla toxins were detected in topping filter (2.8, 3.5 and 8.8 mug/the three doses, respectively).