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Chemical substances

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Penicillin is a group of antibiotics which include penicillin G, penicillin V, procaine penicillin, and benzathine penicillin. Penicillin antibiotics were among the first medications to be effective against many bacterial infections caused by staphylococci and streptococci. They are still widely used today, though many types of bacteria have developed resistance following extensive use.



Plastic is material consisting of any of a wide range of synthetic or semi-synthetic organic compounds that are malleable and so can be molded into solid objects.



Gluten is a composite of storage proteins termed prolamins and glutelins and stored together with starch in the endosperm of various cereal (grass) grains. It is found in wheat, barley, rye related species and hybrids and products of these. Glutens, and most especially the Triticeae glutens, are appreciated for their viscoelastic properties. Gluten gives elasticity to dough, helping it rise and keep its shape and often gives the final product a chewy texture.

Food, Science


Beer is one of the oldest and most widely consumed alcoholic drinks in the world, and the third most popular drink overall after water and tea. Beer is brewed from cereal grains—most commonly from malted barley, though wheat, maize (corn), and rice are also used. During the brewing process, fermentation of the starch sugars in the wort produces ethanol and carbonation in the resulting beer. Most modern beer is brewed with hops, which add bitterness and other flavours and act as a natural preservative and stabilizing agent. Other flavouring agents such as gruit, herbs, or fruits may be included or used instead of hops. In commercial brewing, the natural carbonation effect is often removed during processing and replaced with forced carbonation.



Glucose is a simple sugar with the molecular formula C6H12O6. Glucose circulates in the blood of animals as blood sugar. It is made during photosynthesis from water and carbon dioxide, using energy from sunlight. It is the most important source of energy for cellular respiration. Glucose is stored as a polymer, in plants as starch and in animals as glycogen.



Proteins are large biomolecules, or macromolecules, consisting of one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific three-dimensional structure that determines its activity.



Gelatin or gelatine is a translucent, colorless, brittle, flavorless food ingredient that is derived from collagen obtained from various animal body parts. It is commonly used as a gelling agent in food, medications, drug and vitamin capsules, photographic films and papers, and cosmetics.



Enzymes are macromolecular biological catalysts. Enzymes accelerate chemical reactions. The molecules upon which enzymes may act are called substrates and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called enzymology and a new field of pseudoenzyme analysis has recently grown up, recognising that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties.



Prions are misfolded proteins with the ability to transmit their misfolded shape onto normal variants of the same protein. They characterize several fatal and transmissible neurodegenerative diseases in humans and many other animals. It is not known what causes the normal protein to misfold; the abnormal three-dimensional structure is suspected of conferring infectious properties, collapsing nearby protein molecules into the same shape. The word prion derives from "proteinaceous infectious particle". The hypothesized role of a protein as an infectious agent stands in contrast to all other known infectious agents such as viruses, bacteria, fungi and parasites, all of which contain nucleic acids.


Acetone peroxide

Acetone peroxide is an organic peroxide and a primary high explosive. It is produced by the oxidation of acetone to yield a mixture of linear monomer and cyclic dimer, trimer, and tetramer forms. The trimer is known as triacetone triperoxide (TATP) or tri-cyclic acetone peroxide (TCAP). The dimer is known as diacetone diperoxide (DADP). Acetone peroxide takes the form of a white crystalline powder with a distinctive bleach-like odor or a fruit-like smell when pure and can explode if subjected to heat, friction, static electricity, concentrated sulfuric acid, strong UV radiation or shock. As a non-nitrogenous explosive, TATP has historically been more difficult to detect, and it has been used as an explosive in several terrorist attacks since 2001.



A polymer is a large molecule, or macromolecule, composed of many repeated subunits. Due to their broad range of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass relative to small molecule compounds produces unique physical properties, including toughness, viscoelasticity, and a tendency to form glasses and semicrystalline structures rather than crystals.



A drug is any substance that, when inhaled, injected, smoked, consumed, absorbed via a patch on the skin, or dissolved under the tongue causes a temporary physiological change in the body.



A mineral is a naturally occurring chemical compound, usually of crystalline form and not produced by life processes. A mineral has one specific chemical composition, whereas a rock can be an aggregate of different minerals or mineraloids. The study of minerals is called mineralogy.


B vitamins

B vitamins are a class of water-soluble vitamins that play important roles in cell metabolism. Though these vitamins share similar names, they are chemically distinct compounds which often coexist in the same foods. In general, dietary supplements containing all eight are referred to as a vitamin B complex. Individual B vitamin supplements are referred to by the specific number or name of each vitamin: B1 = thiamine, B2 = riboflavin, B3 = niacin, etc. Some are better known by name than number: niacin, pantothenic acid, biotin and folate.


Vitamin A

Vitamin A is a group of unsaturated nutritional organic compounds that includes retinol, retinal, retinoic acid, and several provitamin A carotenoids. Vitamin A has multiple functions: it is important for growth and development, for the maintenance of the immune system and good vision. Vitamin A is needed by the retina of the eye in the form of retinal, which combines with protein opsin to form rhodopsin, the light-absorbing molecule necessary for both low-light and color vision. Vitamin A also functions in a very different role as retinoic acid, which is an important hormone-like growth factor for epithelial and other cells.