Related Experiment Video

Updated: Jul 12, 2026

Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
15:19

Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor

Published on: October 15, 2015

Dehalogenation: a novel pathway for the anaerobic biodegradation of haloaromatic compounds

J M Suflita, A Horowitz, D R Shelton

    Science (New York, N.Y.)
    |December 10, 1982
    PubMed

    More Related Videos

    Isolation, Propagation, and Identification of Bacterial Species with Hydrocarbon Metabolizing Properties from Aquatic Habitats10:03

    Isolation, Propagation, and Identification of Bacterial Species with Hydrocarbon Metabolizing Properties from Aquatic Habitats

    Published on: December 7, 2021

    A Toolkit to Enable Hydrocarbon Conversion in Aqueous Environments20:28

    A Toolkit to Enable Hydrocarbon Conversion in Aqueous Environments

    Published on: October 2, 2012

    Related Concept Videos

    Microbial Bioremediation of Pesticides01:28

    Microbial Bioremediation of Pesticides

    Pesticides often feature structurally complex chemical architectures, incorporating halogen groups and multiple aromatic rings. These characteristics confer high chemical stability, rendering many pesticides resistant to natural degradation processes. This resistance poses significant environmental concerns, as persistent pesticide residues can accumulate in ecosystems and affect non-target organisms.Despite the inherent stability of many pesticides, certain microorganisms possess the metabolic...
    Multiple Halogenation of Methyl Ketones: Haloform Reaction01:28

    Multiple Halogenation of Methyl Ketones: Haloform Reaction

    A method involving the transformation of methyl ketones to carboxylic acids using excess base and halogen is called the haloform reaction. It begins with the deprotonation of α hydrogen to form an enolate ion which reacts with the electrophilic halogen to give an α-halo ketone. The step continues until all the α protons are substituted to form a trihalomethyl ketone. The resulting molecule is unstable, and in the presence of a hydroxide base, it readily undergoes nucleophilic acyl substitution.
    Radical Substitution: Halogenation of Alkanes and Alkyl Substituents01:27

    Radical Substitution: Halogenation of Alkanes and Alkyl Substituents

    In the presence of heat or light, alkanes react with molecular halogens to form alkyl halides by a substitution reaction called radical halogenation. This reaction has three steps: initiation, propagation, and termination, as seen in the radical chlorination of methane to produce methyl chloride.
    In the initiation step of the reaction, the chlorine molecule undergoes homolytic cleavage in the presence of light or heat, forming two highly reactive chlorine radicals. Propagation occurs in two...
    Halogenation of Alkenes02:46

    Halogenation of Alkenes

    Halogenation is the addition of chlorine or bromine across the double bond in an alkene to yield a vicinal dihalide. The reaction occurs in the presence of inert and non-nucleophilic solvents, such as methylene chloride, chloroform, or carbon tetrachloride.
    Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
    Base-Promoted α-Halogenation of Aldehydes and Ketones00:51

    Base-Promoted α-Halogenation of Aldehydes and Ketones

    α-Halogenation of aldehydes and ketones is a reaction involving the substitution of α hydrogens with halogens in the presence of a base.  The reaction begins with the abstraction of  α hydrogen by the base to produce a nucleophilic enolate ion. This intermediate undergoes a subsequent nucleophilic substitution with the halogen to produce a monohalogenated carbonyl compound. If the starting substrate has more than one α hydrogen, it is difficult to stop the reaction at the stage of...
    Acid-Catalyzed α-Halogenation of Aldehydes and Ketones01:21

    Acid-Catalyzed α-Halogenation of Aldehydes and Ketones

    By replacing an α-hydrogen with a halogen, acid-catalyzed α-halogenation of aldehydes or ketones yields a monohalogenated product
    In the first step of the mechanism, the acid protonates the carbonyl oxygen resulting in a resonance-stabilized cation, which subsequently loses an α-hydrogen to form an enol tautomer. The C=C bond in an enol is highly nucleophilic because of the electron-donating nature of the –OH group. Consequently, the double bond attacks an electrophilic halogen to form a...