Omo. Elmaghraby et Ma. Abdelsater, MYCOFLORA AND NATURAL OCCURRENCE OF MYCOT OXINS IN TOBACCO FROM CIGARETTES IN EGYPT, Zentralblatt fur Mikrobiologie, 148(4), 1993, pp. 253-264
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).