xenobiotic


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xenobiotic

 [ze″no-bi-ot´ik]
a chemical compound foreign to a given biological system. With respect to animals and humans, xenobiotics include drugs, drug metabolites, and environmental compounds such as pollutants that are not produced by the body. In the environment, xenobiotics include synthetic pesticides, herbicides, and industrial pollutants that would not be found in nature.

xen·o·bi·ot·ic

(zen'ō-bī-ot'ik),
1. A pharmacologically, endocrinologically, or toxicologically active substance not endogenously produced and therefore foreign to an organism.
2. Pertaining to association of two animal species, usually insects, in the absence of a dependency relationship, as opposed to parasitism.
[xeno- + G. bios, life + -ic]

xenobiotic

(zĕn′ə-bī-ŏt′ĭk, zē′nə-)
adj.
Not a natural component of a particular organism or biological system. Used of chemical compounds.
n.
A xenobiotic chemical, such as a pesticide.

xenobiotic

[-bī·ot′ik]
Etymology: Gk, xenos, strange, bios, life
a chemical compound foreign to a given biological system. With respect to animals and humans, xenobiotics include drugs, drug metabolites, and environmental compounds, such as pollutants that are not produced by the body. In the environment, xenobiotics include synthetic pesticides, herbicides, and industrial pollutants that would not be found in nature.

xen·o·bi·ot·ic

(zen'ō-bī-ot'ik)
A pharmacologically, endocrinologically, or toxicologically active substance not endogenously produced and therefore foreign to an organism.
[xeno- + G. bios, life + -ic]

xenobiotic

a chemically synthesized compound that is found in the natural environment, but that does not normally occur in nature. Examples include pesticides, dyes, industrial pollutants. Such compounds may be structurally related to natural compounds and may be degraded slowly by the ENZYMES that degrade the natural counterparts. Others may be structurally unrelated to any known natural compound and their degradation occurs very slowly if at all. Xenobiotics generally persist in environments where microorganisms capable of their degradation do not naturally occur.

xen·o·bi·ot·ic

(zen'ō-bī-ot'ik)
Pharmacologically, endocrinologically, or toxicologically active substance not endogenously produced and therefore foreign to an organism.
[xeno- + G. bios, life + -ic]

xenobiotic

any substance, harmful or not, that is foreign to the animal's biological system.

xenobiotic transformation
the principal mechanism for maintaining homeostasis during exposure to small foreign molecules such as drugs and toxins; the process deals with foreign chemicals which are too small for processing by the immune system; composed of enzyme systems evolved to render xenobiotics easily excreted, mainly in the liver; enzymic reactions classified as Phase I (add to or expose functional chemical groups; includes cytochrome P-450 monooxygenases) and Phase II (glucuronidation, conjugation and other reactions producing a large increase in water solubility to promote excretion). Cats lack the capacity for glucuronidation, making them more susceptible to certain poisonings, e.g. acetaminophen (paracetamol).
References in periodicals archive ?
Living cells are exposed to many intrinsic and extrinsic genotoxic factors like xenobiotics and reactive oxygen species (ROS).
Various chelating agents might be required to detect and treat mercury, arsenic, and other xenobiotics.
The investigation of metabolic behavior and metabolism xenobiotic plays an important role in understanding the molecular mechanism of the chemical and its effect at large.
Regulation of drug-metabolizing enzymes by xenobiotic receptors: PXR and CAR.
Chapter 26 covers poisoning that can occur through practice of Cajun, Voodoo, and Hoodoo traditions with the discussions covering some of the xenobiotics used in the practice of these traditions.
Among the most aggressive xenobiotics on the equilibrium of ecosystems are cited some pollutants such as pesticides [1].
Genetical predisposition to resist xenobiotic stress could, in principle, be explained in terms of single nucleotide polymorphisms (SNPs) of complex MDR system components, starting from drug transporters, censoring receptors, and xenobiotic/drug metabolising enzymes (see several examples below).
It can nonspecifically oxidize a variety of phenolic and non- phenolic substances including lignin and various other xenobiotic pollutants [6].
Hoyer (physiology, University of Arizona) and her contributors present a compilation of chapters treating this important subject with new information related to the impact of xenobiotic chemicals on ovarian function.
By supporting healthy xenobiotic elimination from the body, as well as by exerting supportive effects on target bio-molecules, cells and tissues, Detox Weight Manager supports healthy weight management, while also enhancing detoxification, according to the company.
Increasing evidence indicates that, in addition to the well-known xenobiotic metabolism genes in cytochrome P450, family 1 (Cyp1), there are other AHR transcriptional targets, including genes involved in cell-cycle regulation and morphogenetic processes, that may play a vital function during embryonic development (Sartor et al.