Selected phenolic compounds in cultivated plants: ecologic functions, health implications, and modulation by pesticides.

Abstract

Phenolic compounds are widely distributed in the plant kingdom. Plant tissues may contain up to several grams per kilogram. External stimuli such as microbial infections, ultraviolet radiation, and chemical stressors induce their synthesis. The phenolic compounds resveratrol, flavonoids, and furanocoumarins have many ecologic functions and affect human health. Ecologic functions include defense against microbial pathogens and herbivorous animals. Phenolic compounds may have both beneficial and toxic effects on human health. Effects on low-density lipoproteins and aggregation of platelets are beneficial because they reduce the risk of coronary heart disease. Mutagenic, cancerogenic, and phototoxic effects are risk factors of human health. The synthesis of phenolic compounds in plants can be modulated by the application of herbicides and, to a lesser extent, insecticides and fungicides. The effects on ecosystem functioning and human health are complex and cannot be predicted with great certainty. The consequences of the combined natural and pesticide-induced modulating effects for ecologic functions and human health should be further evaluated.

Nutritional composition of vegetables grown in organic and conventional cultivation systems in Uberlndia, MG

“…In the work of Rocha et al (2008), there was no difference in fiber content between organic and conventional foods, however, according to Daniel et al (1999), the application of some herbicides can increase or decrease the secondary metabolites content, including total phenols, which leads to an uncertainty in the fiber content of conventional foods in Rocha's work.…”

“…In the other vegetables, it is observed that there was a trend of higher fiber content on crops grown organically even with no significant difference occurred. As lignin is part of the total fiber and its structure contains phenols, it is possible that the type of cultivation may interfere with the increase of phenolic compounds since these compounds are produced by the plant as a defense against pathogens (Daniel et al, 1999).…”

Biochemical Characteristics, Antimicrobial and Mutagenic Activity in Organically and Conventionally Produced Malus domestica, Annurca

“…Generally, the content of polyphenols may be expected in vegetable organisms also as reaction against biotic or abiotic stress. The application of pesticides and fertilisers has been previously reported to affect the biosynthesis of phenolics in plants, substituting their action, so that conventionally grown plants generally show a phenol content lower than the same but organically grown varieties [19,20]. …”

Phytoestrogen signaling and symbiotic gene activation are disrupted by endocrine-disrupting chemicals.

“…Such studies have shown that synthesis of phenolic phytoestrogens, necessary for recruiting soil bacteria for symbiosis, is altered by the application of pesticides (Daniel et al 1999). Herbicide application reduces the total amount of and alters the production levels of multiple phytochemicals in treated plants (Daniel et al 1999).…”

“…Such studies have shown that synthesis of phenolic phytoestrogens, necessary for recruiting soil bacteria for symbiosis, is altered by the application of pesticides (Daniel et al 1999). Herbicide application reduces the total amount of and alters the production levels of multiple phytochemicals in treated plants (Daniel et al 1999). These findings are significant because the amount and exact profile of phytochemicals produced by a plant directly correlates with its ability to signal and recruit symbiotic soil bacteria (Daniel et al 1999;Peters and Long 1988).…”