AFLATOXIN CONTROL THROUGH TARGETING MECHANISMS GOVERNING AFLATOXIN BIOSYNTHESIS IN CORN AND COTTONSEED
Location: Food and Feed Safety Research
Title: Global Perspectives of Fungal Secondary Metabolite Research
Submitted to: Mycopathologia
Publication Type: Abstract Only
Publication Acceptance Date: October 15, 2006
Publication Date: October 30, 2006
Citation: Bhatnagar, D., Cary, J.W. 2006. Preface: Global Perspectives of Fungal Secondary Metabolite Research. Mycopathologia. 162:141-142.
Fungi produce a wide range of unusual metabolites, termed secondary metabolites because they play no role in the normal, basic metabolic pathways used for growth and energy production, etc. Some of these secondary metabolites have antibiotic properties; others are potent toxins that are dangerous when ingested by humans or other animals; and still others include pigments inserted into the fungal walls or released into the surrounding environment. The range of these metabolites is almost endless, and most of them have no known roles. The diverse metabolic pathways of fungi generate many commercial products such as ethanol, organic acids and enzymes as well.
Mycotoxins, as a group, are the most significant of fungal secondary metabolites having received considerable attention worldwide. It is estimated that almost a third of the world’s food supply is contaminated with mycotoxins. Toxic effects of these compounds have been documented since the Middle Ages, and modern mycotoxicology began over four decades ago with the discovery of aflatoxins in the early 1960's. Since then, researchers have made significant strides in developing a clear understanding of the major classes of mycotoxins and the fungi that produce them; methods for detection and analysis of these secondary metabolites; elucidation of their toxic effects; and methods to control or reduce the contamination of commodities with these compounds. Mycotoxins negatively impact agriculture and associated industries, in one form or another, in all parts of the globe. Regulations exist in many countries prohibiting the sale of contaminated commodities, and the negative economic effect of these regulations has been estimated to be in the millions of U.S. dollars annually. Therefore, from “field to fork,” the presence of mycotoxins in agricultural crops and finished food and beverage products represents both an economic hardship as well as a health risk to humans and livestock.
In spite of four decades of global research establishing the extent of mycotoxin contamination, its role in recurrent episodes of chronic and acute toxicities, and the extensive economic and social costs associated with these compounds, mycotoxin contamination is still not considered to be epidemic. Some of the reasons for this may be that reports of outbreaks and deleterious effects worldwide are often contradictory. Diagnosis of mycotoxicoses in animals is difficult, as symptoms may be similar to those of diseases with other causes. Moreover, the effects of mycotoxins are usually synergistic. Efforts to draw attention to mycotoxins has been met with limited success around the globe. Countries must often weigh the health risks associated with the sale of mycotoxin contaminated commodities with those of economic reward. This is especially true for developing countries. Therefore, there are currently no uniform regulations worldwide for foodborne mycotoxin contamination of commodities. To tackle the mycotoxin menace, a united effort is required, with better cooperation amongst researchers, particularly in the developed world, so that ultimately the developing countries can benefit from this coordinated research effort to minimize, if not eliminate, the negative economic and health impacts of mycotoxins worldwide.
This special issue (as a follow-up to the earlier Mycopathologia special issue on this topic) is designed to provide the reader with a sampling of an international perspective (both agricultural and industrial) of the types of research programs being undertaken to define the benefits that can be derived from fungal metabolism, and to monitor and reduce the incidence of toxic secondary metabolites in the food chain. Authors have addressed the latest technologies on biocontrol of mycotoxigenic fungi, detection of mycotoxins (biosensors) in the food supply and use of genomics for prevention of toxin contamination, as well as improvement of fungal strains used in the fermentation industry. Those interested in analysis of fungal genomes for strain improvement, biosensors, biological control and international perspectives on this increasingly important topic will benefit from the discussions provided in this issue.