Glycerides review

A lipase has been defined as an enzyme that hydrolyzes the esters from emulsified glycerides at an oil-water interface (Desnuelle 1961). This review adheres to this definition as a consequence, investigations which involve water-soluble substrates or substrates containing an alcoholic moiety other than glycerol have not been included. 

In a study designed to investigate the structural features of a phospho-glyceride interaction with a bacterial phospholipase C, El-Sayed et al. (1985), reported that the carbonyl group and its closely related environment are most important. A more detailed treatment of the substrate specificity of this enzyme can be found in an excellent review by Massing and Eibl (1994). 

Croton Oil. Fixed oil expressed from seeds of Croton tiglium L., Euphorbiaceae. Constit. Croton resin—a powerful vesicant glycerides of stearic, palmitic, myristic, lauric. tiglic, etc., acids crotin phorbol (q. v.) esters. Review Meeker, Schmidt. Fortschr. Chem. Org. Naturst. 31, 377 (1974). 

Hydrolyzes fat (present in ester form, such as glycerides) yielding fatty acids and glycerol. Catalyzes digestion. Widely distributed in the plant world, also in molds, bacteria, milk and milk products, and in animal tissues, especially in the pancreas, [soln from castor beans H. Gibian in Ullmann s Encyklopadie der technischen Chemie, 3rd ed., vol. 7, 406 -407 (1956). Purification of pancreatic lipase March s-Mouren el al.. Arch, Biochem. Biophys. 83, 309 (1959), Review of milk lipases Chan dan, Shahani, J, Dairy Sri. 47, 471 (1964). Comprehensive reviews Wills, Ad van. Lipid Res. 3, 197-240 (1965) Desnuelle in The Enzymes vol, 7, P. D. Boyer, Ed. (Academic Press, New York, 3rd ed<> 1972) pp 575-616. 

While no esters were reported in tobacco smoke by Kosak (2170) in his 1954 compilation of reported tobacco smoke components, the number of esters in tobacco and its smoke has increased dramatically over the years and now exceeds 1000. In 1955, Latimer (2270) collated and reported component data from Chemical Abstracts and listed only one set of esters reported in tobacco and its smoke, the glycerides. In 1959, Johnstone and Plimmer (1971) listed sixteen identified esters from these two sources. Between the Johnstone and Plimmer review and that of Stedman (3797) in 1968, the number of identified esters in tobacco and/or smoke escalated to over 300. 

Digestion of usual food fats and subsequent absorption of their digestion products (2), the in vitro digestion profiles of long-and medium-chain glycerides, and the phase behavior of their lipolytic products have been reviewed recently (3). In the present review, the stereospecific aspects will be highlighted. 

A nomenclature for lipid crystal forms, originally proposed for glycerides (Larsson, 1966), was later applied also to other lipids and will be used in the present review. The nomenclature is based on the following three criteria ... 

Gas chromatography (GC) and MS have long been used in conjuction, as we have repeatedly mentioned. However, GC is not suitable for the separation of glycerides and other complex lipids, because these molecules are thermolabile. Liquid chromatography provides a suitable substitute for MS lipid analysis (Fig. 9.35). Techniques for coupling LC with MS have been reviewed by Privett and Erdahl (1978) these authors have also described an interface for the analysis of lipids by MS. This interface is based on the moving wire transport principle using an endless stainless-steel belt (Erdahl and Privett, 1977). After evaporation of the solvent, the solute remains as a... 

Glyceride Synthesis. - This topic has been reviewed. Eibl... 

Lipids are important as pheromones, precursors of pheromones, or carriers of pheromones in plants and animals. The topic has been reviewed for vertebrates and insects by Shorey (1976) and for invertebrates (mainly helminths) other than insects by Haseeb and Fried (1988). Lipophilic pheromones or their carriers are mainly glycerides, free fatty acids, and sterols. Insects excrete long-chain alcohols, alkyl acetates, aldehydes, and ketones that serve as intraspecific pheromones (Mahadevan and Ackman, 1984). 

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