Скачать или смотреть Xenobiotic Metabolism; Definition, Purpose, Phases, Factors Influencing

Xenobiotic Metabolism is the process by which organisms transform and eliminate foreign substances—called xenobiotics—that aren't naturally produced by the body. These include drugs, pollutants, food additives, and industrial chemicals. The goal? To detoxify and safely excrete these compounds.

🔍 Key Phases of Xenobiotic Metabolism
Phase I – Functionalization

Enzymes like cytochrome P450 oxidases introduce reactive or polar groups.

Reactions include oxidation, reduction, and hydrolysis.

This step often makes the compound more chemically active (sometimes even more toxic).

Phase II – Conjugation

The modified xenobiotic is linked to endogenous molecules like glucuronic acid, sulfate, or glutathione.

These reactions increase water solubility, aiding excretion.

Enzymes involved include glutathione S-transferases and UDP-glucuronosyltransferases.

Phase III – Transport

Conjugated xenobiotics are recognized by efflux transporters.

These transporters pump the compounds out of cells for elimination via urine or bile.

🧬 Why It Matters
Drug Metabolism: Determines how quickly and effectively medications work.

Toxicology: Helps assess risks from environmental chemicals.

Pharmacokinetics: Influences absorption, distribution, metabolism, and excretion (ADME) of drugs.

Environmental Science: Microbial xenobiotic metabolism is key in bioremediation efforts.

#Xenobiotic #Metabolism