Interactions of Fungicides and Pesticides with Specific Enzymes

This chapter concerns influences of fungicides and pesticides on specific enzymes of various living systems. There is a growing interest on enzyme systems and environmental factors affecting them in the field of biochemistry and molecular biology. As known, fungicides, pesticides and other chemicals can enter rain water, food, irrigation water or rivers in many cases, and may be hazardous for living systems. Many chemical substances including fungicides, pesticides, drugs and metal ions influence metabolism at very low concentrations by altering enzyme activities and disrupting physiological balances. Many biocides are known to interfere with a number of processes as they have neurotoxic, hematotoxic, genotoxic, hepatic and renal effects on vertebrates (Hayes, 1990; Pretty & Hine, 2005; Ecobichon, 1996; WHO, 1967; Eisler, 1996). Although there are numerous examples of applications of widely used pesticides and fungicides, little is known about their effects on specific enzymes in organisms and there is a serious lack of data and information on exposures, effects and biological evaluation that connect them. Whereas the effects of several factors on enzyme levels and activity is reasonably well appreciated, the effects of xenobiotic exposure on specific enzyme systems have not received substantial review yet. Relevant xenobiotics are derived from pharmaceutical, nutraceutical and environmental exposure, and many of the mechanisms involved are highly complex in nature, not easily predictable from existing in vitro tests and do not always predict well from in vivo animal models. After a detailed review of enzymes, fungicides and pesticides, a framework for considering the different levels of direct and indirect modulation by xenobiotics is developed herein, and areas that still require further investigation are highlighted. It is anticipated that this chapter may help explain some of the variation in levels of specific enzymes, guide the direction of long-term drug/nutraceutical safety trials, and stimulate ideas for future research.