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Sucrose (α-d-glucopyranosyl-(1→2)-β-d-fructofuranoside) is an inexpensive chemical produced by sugar cane and sugar beet cultivation. Chemical and/or biochemical transformations convert it into highly valuable synthetic intermediates such as 5-hydroxymethylfurfural (HMF), bioethylene, 1,2-propylene glycol and levulinic acid. Sucrose can also be converted into biodegradable polymers such as polyesters and polyurethanes, as well as into novel carbohydrates such as isomaltulose, trehalulose, inulin, levan, Neo-amylose, and dextran, highly valuable additives for food and cosmetics and materials for separation and purification technologies. [ABSTRACT FROM AUTHOR]

'tis, we musicians know, the C Major of this life. Paintings and museum reconstructions depicting the activities of medieval alchemists can easily give the wrong impression of the chemical knowledge of that period. Inanimate objects such as crystals are seen sharing shelves with the preserved bodies of small creatures, a common feature of the early laboratory. This could be taken to suggest that the scientists of those days had grasped the unity of chemistry: that in spite of great differences in their external appearance, Nature makes no distinction between chemical combinations in living and dead substances. Nothing could be farther from the truth. The universally held belief was that the matter contained in living organisms possessed an essential extra ingredient, a vital force, the mysterious origin of which was attributable to divine powers. This attitude was epitomized in the succinct classification to be found in the book Cours de Chyme, published by Nicholas Lemery in 1685. His division is still to be found in the standard first question of a popular parlour game: ‘animal, vegetable or mineral?’. By the end of the eighteenth century, the vital force theory was in rapid decline. Antoine Lavoisier, analyzing typical organic compounds, found them to contain inorganic substances such as hydrogen, oxygen, nitrogen, carbon, sulphur and phosphorus. The basic principles that govern chemical change, such as conservation of total mass, were being established during this period, and in 1844 Jöns Berzelius showed that they apply to all matter irrespective of whether it is inorganic or organic. [ABSTRACT FROM AUTHOR]

The article deals with the acid esters microbicides including ethyl formate, ethyl bromoacetate and benzyl bromoacetate among others. It offers information on their chemical and structural formulas, molecular mass, chemical and physical properties, toxicity and antimicrobial effectiveness and applications.

The article deals with the preservatives used for food and beverage preservation including benzoic acid, sorbic acid, propionic acid, sulfur dioxide, nitrite, esters of p-hydroxybenzoic acid, nisin and pimaricin among others. It offers information on the other names, acute toxicity, antimicrobial action and applications of the preservatives.

When trying to classify or to subclassify material protecting microbicides to their mode of action, e.g. as membrane-active and electrophilically active agents, it turned out that a clear assignment is not always possible. For that reason it has been resorted to chemistry’s principle of classifying, i.e. organisation of microbicides by the following groupings: Alcohols — Aldehydes — Aldehyde releasing compounds — Phenol derivatives — Acids — Acid esters — Amides — Carbamates — Dibenzamidines — Pyridine derivatives — Azoles — Heterocyclic N, S compounds — Compounds with activated halogen atoms — Surface-active agents — Organometallic compounds — Various compounds — Oxidizing agents Such a classification provides in most cases the first necessary information about a microbicide’s properties. The data sets inform about the chemical and physical properties of the microbicides, their toxicity (including their ecotoxicity), their antimicrobial effectiveness and applicability. Sources for toxicity data are, if not otherwise indicated: Supplier names do not claim to be always complete and up-to-date. Nowadays it is not rare that active agents have been discontinued, or being made by another company; corporate takeovers, or the shift of microbicides to a new company have also taken place. [ABSTRACT FROM AUTHOR]

Chapter 2.3 of the book "Vitamin & Mineral Requirements in Human Nutrition" is presented. Most of the circulating vitamin A is retinol whereas in most tissues, secretions and other animal food sources, it exists mainly as retinyl esters, which are frequently hydrolysed before analytical detection. It mentions the efforts of the World Health Organization to express the vitamin A activity of carotenoids in diets on a common basis.

Description of the vitamin "Retinol concentrate" is presented. It is noted that vitamin A concentrate is of yellow to brownish yellow in color. It is a composition of ester or a mixture of esters usually prepared by synthesis. Details regarding the relative molecular mass, physical description, solubility, and storage are provided. Tests for the identification of this substance are listed. Information about the mass density, water content and acidity test is also provided.

An encyclopedia entry for phthalate esters is presented. Phthalate esters are di- and mono-esters of phthalic acid. These compounds are widely used as industrial plasticizers to coat polyvinylchloride surfaces of plastics and are common environmental contaminants.

A definition of the term "esterases" is presented. It refers to any group of enzymes that hydrolyze esters into alcohols and acids.

A definition of the term "chromate" is presented. It refers to the hexavalent monomeric base salt or ester of chromic acid.

The article presents an encyclopedia entry for the term "phorbol esters." It refers to the isolated diterpene esters from croton oil. The plane Croton tiglium produces croton oil. The prototypical phorbol ester promotes tumour production and triggers protein kinase C isoforms.

A definition of the term "organic nitrates" is presented. The term refers to polyol esters of nitric acid. Glyceryl trinitrate or nitroglycerine, isosorbide mononitrate and amyl nitrite are included in this group of drugs. A process involving an enzymatic step causes organic nitrates to release nitric oxide. At clinical concentrations, organic nitrates lead to a relaxation of venous capacitance vessels.