Triterpenes biological activities

SCHEME 8.15 Various triterpene QMs with broad biological activities. 

The utility of mass selective detection is greatest when analyzing compounds that do not contain chromophores or when structural information is needed for chemical identification. Triterpene saponins contain very weak chromophores and have long been associated with a variety of biological activities including... 

The biological activity and toxicity of terpenoids to herbivores has been discussed (56,84) and representatives of each major type of terpene are known to be active. Well known examples are sesquiterpene lactones, pyrethrins, and several classes of diter-penes and triterpenes. 

BIOLOGICALLY ACTIVE TRITERPENE GLYCOSIDES FROM SEA CUCUMBERS (HOLOTHUROIDEA, ECHINODERMATA)... 

TRITERPENE GLYCOSIDES FROM SEA CUCUCMBERS (HOLOTHURIOIDEA, ECHINODERMATA). BIOLOGICAL ACTIVITIES AND FUNCTIONS... 

Many kinds of biological activities of holothurian triterpene glycosides are a result of their membranol)dic action, i. e. their capability to induce disturbances in cellular membrane permeability up to lysis. 

The biological activities depend on the structures of holothurian triterpene glycosides [42-44]. The structures of both an aglycon part and a carbohydrate chain are very important for the antifungal activity. The 18(20)-lactone presence is necessary for the activity, because the derivative 49 without the lactone does not show antifungal properties. 

The importance of a linear tetrasaccharide fragment and an 18(20)-lactone for biological activity, the absence of a significant contribution of 4-0-sulfate at first xylose to activities of tetraosides and, in contrast, its important role for activity of biosides were shown for hemolytic action of triterpene glycosides from sea cucumbers [33]. It confirmed a common mechanism of their activity against membranes of both erythrocytes and fungal cells. 

GRAPHICAL INTERPRETATION OF BIOLOGICAL ACTIVITIES AND BIOLOGICAL ROLE OF SEA CUCUMBER TRITERPENE GLYCOSIDES... 

Therefore, the ability to modify the structural organization of cellular membranes by different modes is the basis of the wide spectrum of biological activities as well as biological roles of sea cucumber triterpene glycosides. 

Biosynthetically-patterned microbiological transformations exploit the substrate flexibility of enzymes involved in the biosynthesis of secondary metabohtes. These biotransformations are sometimes known as analogue biosynthesis or precursor-directed biosynthesis. This approach to biotransformation can be useful in preparing analogues of biologically-active microbial metabolites for structure-activity studies, a feature that has been exploited with penicillins using a cloned isopenicillin N synthase. The structures of the substances that are transformed and of their products can also shed light on the stereo-electronic constraints of enzymatic steps and on the nature of biosynthetic intermediates, a feature that has been exploited in studies on the cyclization of squalene to the triterpenes and steroids. 

Triterpenes belong to a wide group of compounds frequently isolated from plant sources. The biosynthetic pathways of many of the skeletons are known and the range of biological activities makes them attractive as potential new drugs. 

A wide range of biological activities has been described for triterpenes and nor-triterpene quinonemethides. These include anti-inflammatory, anti-hyperlipidemic, antitumour-promotion, hepatoprotective, anti-ulcer, anti-microbial and hypoglycemic activitiy, among others [16,35]. Among the compound mentioned previously in this review, antitumour-promotion, anti-inflammatory, inmunosuppressive, anti-tumour, insecticide and anti-AIDS activities were found and are described below. 

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