Microbiology Notes | Biochemistry,Immunolgy,Cell biology

What Is Xenobiotic Compound? Xenobiotic compounds are man-made chemicals that are present in the environment at unnaturally high concentrations. The xenobiotic compounds are either not produced naturally, or are produced at much lower concentrations than man. Microorganism have the capability of degrading all naturally occurring compounds; this is known as the principle of microbial infallibility proposed by Alexander in 1965. Microorganisms are also able to degrade many of the xenobiotic compounds, but they are unable to degrade many others. The compounds that resist biodegradation and thereby persists in the environment are called recalcitrant The evolution of microbial catabolic enzymes cannot keep pace with the rapid introduction of novel compounds into the environment. These new synthetic compounds that are slowly biodegradable or non-biodegradable are known as recalcitrant compounds, and range from simple halogenated hydrocarbons to complex polym...

For biotoxification or Biodegradation of toxic substances Required a special enzyme which contain encoded gen on Plasmid Dr. Ananda Mohan Chakrabarty  and his co-workers are isolated a specific organism which is known as Pseudomonas putida in 1989.which can utilize some toxic chemical substances such as 3 chlorobenzene,ethylene etc. Pseudomonas putida  is a Gram-negative, rod-shaped, saprotrophic soil bacterium. V A variety of  P. putida , called multiplasmid hydrocarbon-degrading  Pseudomonas , is the first patented organism in the world. Because it is a living organism, the patent was disputed and brought before the United States Supreme Court in the historic court case  Diamond v. Chakrabarty , which the inventor, Ananda Mohan Chakrabarty, won . P. putida is a multiplasmid containing orgamism which contain more then one plasmid they introduce by genetic engineering different types of plasmid into a cell and forme...

Bioremediation  is a process where biological organisms are used to remove or neutralize an environmental contaminant or waste. The ‘bio-‘ part refers to the biological organisms, which typically includes microscopic organisms, like fungi and bacteria. And, the ‘-remediation’ part refers to remedying the situation ,It is an environment friendly processes. According to Wikipedia, “Bioremediation is a waste management technique that involves the use of organisms to remove or neutralize pollutants from a contaminated site.” According to the EPA, Bioremediation is a “treatment that uses naturally occurring organisms to break down hazardous substances into less toxic or non toxic substances.” Advantage there is no uses of chemical substances It allow the waste to Recycle Classificatin of Bioremediation There are two classes of bioremediation – 1 . In-situ Bioremidiation: In-situ bioremediation  means that you allow bioremediat...

Definition Radionuclide Pollution or Radionuclide Contamination is define as when the radioactive molecules are present on surface of solide,water,air or in human skin which is undesirable is called radionuclide contamination addition of radiation in environment from radioactive element is called Radionuclide Pollution. Radioactive pollution is like any other kind of pollution in which some unwanted elements are release into environment,this unwanted element is called Radioactive Pollution. Radioactive elements are spread through the earth atmosphere is called Fallout The measurement unit of Radioactivity is Disintegration or decays, per unit time.common unit of radioactivity is Becquerel, equal to 1 decay per second.and curie, equal to the 37 billion decay per second. Source The sources of radioactive pollution can be classified into two groups: natural and man made. Natural Source: 1.Cosmic Radiation 2.Internal Radiation 3.Terrestrial Radiation Man Ma...

Ionizing Radiation The high energy containing electron waves are called ionizing radiation which can pull electrons from orbit. Example, ultraviolet light, X-rays, gamma-rays They have very high frequencies (in the range of 100 billion billion hertz) and very short wavelengths (1 million millionth of a metre). Mode of action They destroy the atom by pull the electrons from the Orbit. They kill the bacterial cell by destroy the DNA Structure.(by forming dimer in DNA nucleotides) Exposure to ionizing radiation Radiation exposure may be internal or external, and can be acquired through various exposure pathways. Internal exposure  to ionizing radiation occurs when a radionuclide is inhaled, ingested or otherwise enters into the bloodstream (for example, by injection or through wounds). Internal exposure stops when the radionuclide ...

Acute toxicity Acute toxicity  describes the adverse effects of a substance that result either from a single exposure or from multiple exposures in a short period of time (usually less than 24 hours). The adverse effects should occur within 14 days of the administration of the substance. Treatments When a person has been exposed to an acutely toxic dose of a substance, they can be treated in a number of ways in order to minimize the harmful effects. Emergency showers  used for removing irritating or hazardous chemicals from the skin. Emergency eye washes  used for removing any irritating or hazardous chemicals from the eyes. Activated charcoal  used to bind and remove harmful substances consumed orally. Chronic toxicity Chronic toxicity , the development of adverse effects as a result of long term exposure to a contaminant or other stressor. The Chronic Toxicity may be lethal or sublethal. Including changes in growth, reproduction...

Definition and Characters of BOD Biochemical Oxygen Demand  (also called Biological Oxygen Demand ) is the amount of dissolved oxygen needed by aerobic biological organisms to break down organic material present in a given water sample at certain temperature over a specific time period. Oxygen dissolved in water can come from the atmosphere or as a byproduct of the photosynthesis of aquatic plants. BOD help to determine either the water is portable or not. If the number of organism is increases then the Amount of BOD will decrease. Aerobic microorganisms used BOD to oxidize the organic component in sewage water. The strength of water is depend on the BOD value and the magnitude of BOD is depend on the organic substances in sewage water. BOD test is used to determine the presence of organisms in water. Reaction and Formula When biodegradable organic matter is released into a water body, microorganisms feed on the wastes, breaking them into simpler organic and inorga...