Oxygen in Biology and Biochemistry: Role of Free Radicals

نویسنده

  • MARCELO HERMES-LIMA
چکیده

A free radical is defined as any atom or molecule that contains unpaired electrons and has independent existence (hence, the term free). A dot is used to represent a free radical species. The abstraction or gain of one electron by a nonradical molecule may (or may not) convert it to a radical species. Free radicals can have positive, negative, or neutral charges [reactions (12.1.1) and (12.1.2)].

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Role of oxygen and nitrogen free radicals in diabetes-induced atherosclerosis and effects of exercise on it

Free radical can be defined as a molecule or molecular fragments containing unpaired electron in the outer orbital, which react with nearby molecules to get stability. There are two types of them in the body: oxygen free radicals and nitrogen free radicals. Our body has an antioxidant defense system which prevents accumulation of these radicals. There is a balance between free radical produc...

متن کامل

Oxidative Stress and its Role in Female Infertility and Assisted Reproduction: Clinical Implications

Reactive oxygen species (ROS) are involved in physiological functions and act as mediators in various signaling processes. Elevated or sustained generation of free radicals and non radical species derived from free radicals can lead to an imbalance in the intracellular redox homeostasis. Normally, any excess levels of reactive radical and nonradical species generated are intercepted by antioxid...

متن کامل

Development of a Method for measuring Reactive Oxygen Radicals Levels In Vitro and Study the Effects of Vitamin C and E on Radical Production Reaction

Background: Free radicals and reactive oxygen species(ROS) are the most important factors in formation of oxidative stress reaction. Now, radical damage has been suggested to contribute to a wide variety of diseases such as Alzheimer, atherosclerosis and cancer. Transition metal ions in the presence of the various biomolecules produce these active compounds. The aim of this study is introducing...

متن کامل

Evaluation of antioxidant activity of natural product compounds from Platycladus orientalis leaves

Background and objectives: Natural product compounds of plants have been used since ancient times and in folklore medicine for the treatment of many diseases and illnesses. Oxygen-centered free radicals and other reactive oxygen species, which are continuously, produced in vivo, result in cell death and tissue damage. Oxidative damage caused by free radicals may be rel...

متن کامل

مروری بر نقش محافظتی ترکیبات پلی فنلی (رسوراترول، کوئرسیتین و کورکومین) بر عملکرد میتوکندری قلب

Mitochondria plays a major role in maintaining homeostasis of heart cells. Mitochondria produce ATP and is the main intracellular source of reactive oxygen species (ROS) which can cause oxidative damage. Free oxygen radicals and oxidative damage are associated with cardiovascular pathology. Antioxidant defense can play an essential role in preventing oxidative damage by controlling free oxygen ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2004