Are Xenobiotics Harmful?

What is xenobiotic degradation?

In other words, defined as the ability of microorganisms to convert toxic chemicals (xenobiotics) to simpler non-toxic compounds by synthesis of certain enzymes • Biodegradation of xenobiotics can be affected by substrate specificity, nutrition source, temperature, pH etc..

What metabolizes caffeine?

Caffeine is primarily metabolised in the liver by cytochrome P450 enzymes, which are responsible for more than 90% of caffeine clearance19.

Is lead a xenobiotic?

Throughout our life span, humans are also exposed to xenobiotic metals from natural and anthropogenic sources, including aluminum, arsenic, cadmium, lead, and mercury.

What is cytochrome p450?

Cytochrome P450 enzymes play a role in the synthesis of many molecules including steroid hormones, certain fats (cholesterol and other fatty acids), and acids used to digest fats (bile acids).

What the body does to the drug is?

Pharmacokinetics, sometimes described as what the body does to a drug, refers to the movement of drug into, through, and out of the body—the time course of its absorption, bioavailability, distribution, metabolism, and excretion.

What does bioavailability mean?

(BY-oh-uh-VAY-luh-bul) The ability of a drug or other substance to be absorbed and used by the body. Orally bioavailable means that a drug or other substance that is taken by mouth can be absorbed and used by the body.

What are xenobiotics and their examples?

Xenobiotic is a term used to describe chemical substances that are foreign to animal life and thus includes such examples as plant constituents, drugs, pesticides, cosmetics, flavorings, fragrances, food additives, industrial chemicals and environmental pollutants.

Why are drugs referred to as xenobiotics?

The term xenobiotics, however, is very often used in the context of pollutants such as dioxins and polychlorinated biphenyls and their effect on the biota, because xenobiotics are understood as substances foreign to an entire biological system, i.e. artificial substances, which did not exist in nature before their …

Are drugs xenobiotics?

Drugs can be considered a subset of xenobiotics, that is, natural compounds of exogenous origin that may find their way into the human body. Other important classes of xenobiotics are potentially toxic plant alkaloids or fungal toxins.

What does the body do to a lipophilic compound during metabolism?

Drug metabolism often converts lipophilic compounds into hydrophilic products that are more readily excreted.

Is DDT a xenobiotic?

1,1,1-Trichloro-2,2-bis-(4′-chlorophenyl)ethane (DDT), the first of the chlorinated organic insecticides, is a widely distributed and persistent xenobiotic contaminant in the environment. DDT is not metabolized very rapidly by animals; instead, it is deposited and stored in the fatty tissues.

Is caffeine a xenobiotic?

Caffeine is one of the most widely used psychoactive drugs in humans, acting as a stimulant, and has been employed as a convenient model xenobiotic in Drosophila research, where it is known to induce the expression of a number of P450 and GST genes in Drosophila S2 cells, larvae and adults [19–22].

What is the meaning of xenobiotics?

Definition. Xenobiotics are chemicals found but not produced in organisms or the environment. Some naturally occurring chemicals (endobiotics) become xenobiotics when present in the environment at excessive concentrations.

What are xenobiotics compounds?

A xenobiotic (Greek, xenos “foreign”; bios “life”) is a compound that is foreign to a living organism. … Xenobiotics may be grouped as carcinogens, drugs, environmental pollutants, food additives, hydrocarbons, and pesticides.

What is a Phase 1 reaction?

Metabolism is often divided into two phases: Phase 1 metabolism involves chemical reactions such as oxidation (most common), reduction and hydrolysis. There are three possible results of phase 1 metabolism. The drug becomes completely inactive. In other words, the metabolites are pharmacologically inactive.

How can xenobiotics be of concern to human?

With the development of the society, the xenobiotics have brought high potential risk to human and animal. Insecticides bring high risk to human and animal through food, water, and air. …

Why xenobiotics are recalcitrant?

But some xenobiotics are recalcitrant in nature because of various reasons. Some of them cannot be used as substrate by microbes, some cannot transport them due to absence of transporting enzymes and some are in accessible to microbes due to larger structure and insolubility.

What is Phase 1 biotransformation?

Phase I biotransformation reactions introduce or expose functional groups on the drug with the goal of increasing the polarity of the compound. … Typically, oxidation is the most common phase I reaction. The hepatic cytochrome P450 system is the most important of the phase I oxidation systems (Figure 1).