Handbook of Herbs and Spices - Volume 3

(sharon) #1

Detecting and controlling mycotoxin contamination of herbs and spices 19


Elshafie et al., (2002) detected mycobiota of seven different spices from a group


consisting of one hundred and five samples. Coriander was found to be the most


heavily fungal contaminated among the spices (18 out of 20) followed by black


pepper, ginger, cinnamon, cumin, and cardamom. Clove was the least contaminated


spice due to its microbial inhibitory effect. Cinnamon was found to be contaminated


by a number of fungi (11 out of 20) including potentially mycotoxin producing fungi.


Fifteen samples of spices (ginger, cumin, cinnamon, clove, black pepper, cardamom,


ginger and coriander) that were heavily contaminated by A. flavus were screened for


the presence of aflatoxins using HPLC. No aflatoxins were detected on the samples.


Of the seven spices studied, clove was found to be the least contaminated, while


cumin was the most heavily contaminated.


Medicinal plants such as peppermint, chamomile, anise, caraway and tilio were


analysed for moulds and aflatoxins (Abou-Arab et al., 1999). Samples were


collected randomly from the Egyptian market. Aspergillus and Penicillium genera


were more frequently detected and in greater abundance in the samples than


other genera of fungi. For the A. flavus infection, the results showed that all tested


medicinal plants were infected with the exception of packed tilio. The highest percentage


of infection was in peppermint (15.8%) followed by non-packed tilio (15.4%) as


well as non-packed caraway (13.5%). The other tested medicinal plants showed


a low percentage of A. flavus. However, natural aflatoxin contamination was not


detected.


Rizzo et al., (2004) studied toxigenic fungi on 56 species of medicinal and aromatic


herbs, which were used as raw material for drugs in Argentina. A. flavus and A.


parasiticus were the predominant species isolated, 50% out of 40 isolates were


toxigenic, 26% of isolates produced OTA in low concentrations, 27% of the isolates


were F. verticilloides and F. proliferatum, which produced fumonisin B 1 and fumonisin


B 2. Other Fusarium species were able to produce neither group A and B trichothecenes


nor zearalenone.


Martins et al., (2001) studied microbiological quality of seven species (chamomile,


leaves of orange tree, flower soft linden, corn silk, marine alga, pennyroyal mint and


garden sage) of 62 medicinal plants in Lisbon, Portugal. Corn silk samples were the


most contaminated. Fusarium spp., Penicillium spp., A. flavus and A. niger were


predominant in all samples with the exception of garden sage.


1.4 Detecting mycotoxins in herbs and spices


Various methods have been published to determine the mycotoxin content of foodstuffs


by international organisations such as the Association of Official Analytical Chemists


(AOAC), the International Union of Pure and Applied Chemistry (IUPAC), the European


Standardization Committee (CEN). However, an official method related to the


determination of mycotoxin in herbs and spices does not exist. The aim of this


section is not to repeat a specific method developed by the official bodies mentioned


above, but to present information regarding issues to be considered during method


selection and application for herbs and spices together with alternative methods that


can be used in mycotoxin analyses of herbs and spices and the recent development in


the field.

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