Mycotoxigenic Fungi in Spices: Molecular Methods of Detection and Control

Shadanaika, Ms. (2005) Mycotoxigenic Fungi in Spices: Molecular Methods of Detection and Control. PhD thesis, University of Mysore.

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Abstract

The occurrence of mycotoxigenic fungi and elaboration of their toxins in agricultural commodities including spices has been viewed with great concern world over, mainly because of their potential health hazards to humans and live stocks and also its impact on economy. Several mycotoxigenic fungi belonging to species of Alternaria, Aspergillus, Cladosporium, Curvularia,Fusarium and Penicillium, are known to contaminate food and agricultural commodities. Amongst mycotoxigenic fungi, Aspergillus flavus group continues to be the predominant fungi and occupies wide variety of human habitats. The mycotoxin contamination in some spices is suspected for two reasons; (1) many spices are cultivated and processed in warm tropical areas, where conditions favor growth of naturally occurring fungi; (2) most of the spice producing countries are developing countries where the drying and storage practices are not satisfactory. Out of 70 spices grown in different parts of the world, 52 of them are cultivated in India and have occupied a prominent place in the national economy with a tag of export potential. Chilli, ginger, turmeric, cardamom and pepper are considered as major spices and have considerable volume of international trade. India exported 246566.32 metric tones of spices worth of Rs 190508.50 during the year 2003-2004. Amongst them, chilli contributed 81500.00 metric tones worth of Rs 35511.25, ginger and turmeric contributed 5000.00 and 34500.00 tones worth of Rs 2340.50 and 12751.88 respectively (Spices Board, 2004). It has been estimated that roughly 25% of the world’s food crops are affected by mycotoxin contamination annually (Magan and Aldred, 2003). Mycotoxins are important as evidenced by occasional outbreaks of human mycotoxicoses and the role of aflatoxins in liver cancer in West Africa and fumonisins in esophageal cancer in South Africa are well established (Shephard, 2004). (ii) The most significant mycotoxigenic Aspergilli are A. flavus, A. parasiticus and A.nomius which produce aflatoxins, A.ochraceus, which produce ochratoxins, and A.versicolor, which produce sterigmatocystin. Aspergillus flavus is of ubiquitous occurrence in nature and produces aflatoxin B1 and B2, while Aspergillus parasiticus produces these same metabolites along with G1 and G2 (Mclean, Dutton 1995). Despite several efforts attempted throughout the world in the field of mycotoxins, some questions are still to be answered. The need for total surveillance, improve sampling and analytical methods, storage facilities and continuously evolving control measure against mycotoxigenic fungi is indispensable. In addition to this, priority towards management of mycotoxins through development of efficient detoxification and decontamination procedures for their regulations needs to be addressed. The presentation of investigations in this thesis deals with a systematic study on spices such as chilli, ginger and turmeric with the following objectives: Objectives : ● Natural occurrence of mycotoxigenic fungi in spices. ● Evaluation of substrate specificity of spices for mycotoxin production. ● Determination of critical moisture level in spices through sorption studies. ● Detection of aflatoxigenic fungi in spices by molecular method. ● Studies on the control of mycotoxigenic fungi.

Item Type:	Thesis (PhD)
Uncontrolled Keywords:	mycotoxigenic fungi spices molecular methods Mycotoxins detection
Subjects:	600 Technology > 08 Food technology > 30 Spices/Condiments 600 Technology > 08 Food technology > 29 Microbiological food > 02 Fungi 500 Natural Sciences and Mathematics > 07 Life Sciences > 03 Biochemistry & Molecular Biology
Divisions:	Human Resource Development
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	03 Dec 2007 11:12
Last Modified:	28 Dec 2011 09:31
URI:	http://ir.cftri.res.in/id/eprint/1531

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