Abstract
Spices form an integral part of regular diets for purposes of flavor. but
are subject to contamination by fungi under optimal storage conditions. To
determine the risk level associated with this factor, 21 samples for each of five
major markets in the city of Erbil were sampled and examined for presence
and infection rates due to fungi.
Fungi were identified by morphological inspection, culture on Potato
Dextrose Agar (PDA) and Czapek Dox Agar (CDA), and molecular sequencing,
while the VITEK 2 system was used to identify yeasts. Mycotoxin levels,
including total aflatoxins and ochratoxin A (OTA), in 16 spice samples were
determined by ELISA. Four of the most frequently used spices (clove, thyme,
fenugreek, and black cumin) were also tested for antifungal potential against
three fungi (Aspergillus flavus, A. niger, and Rhizopus oryzae) isolated from
spices and three yeasts (Candida albicans, C. tropicalis, and Clavispora
lusitaniae) isolated from clinical strains.
The analysis for species identified 8 genera and 19 species, the most
important species including Aspergillus flavus, A. niger, A. terreus, A. carneus,
A. ustus, Rhizopus oryzae, R. stolonifer, Mucor sp., and Alternaria alternata.
The total number of fungi in the sample was 94 × 10³ cfu/g in PDA and 60 ×
10³ cfu/g in CDA. Aspergillus was the most common mold followed by
Rhizopus while Penicillium and Fusarium were not found. Turmeric, cumin,
Coriander and Anise contained maximum contamination while no
contamination was observed in clove and minimum contamination was found
in Thyme, fenugreek and Cubeb. Among the Fungi detected by molecular method were A. flavus, A. niger, Rhizopus oryzae and an infrequent species A. welwitschiae. VITEK 2 also picked up Cryptococcus sp. as well as Candida spp. ELISA revealed that nearly all spice samples contained aflatoxins at toxic levels, although Ochratoxin A levels varied: three spices (black cumin, cubeb,and cinnamon) exceeded European Commission safety limits, whereas others (mustard, curry powder, cumin, red pepper, coriander, oregano, black pepper, pul biber, cardamom, white pepper, anise, turmeric, and yellow dried lime) were below safe limits. Among the plant extracts screened, clove exhibited the highest antifungal activity against both the molds and yeasts, thyme and fenugreek exhibited moderate activity, while black cumin exhibited negligible or no inhibitory effect.These findings illustrate the health hazards of fungal and mycotoxin contamination in spices commonly consumed in Erbil and the potential for certain spice extracts, in particular clove, to serve as natural antifungal agents.
