Glycosylated secondary metabolites

Saponins are glycosylated secondary metabolites that are widely distributed in the Plant Kingdom.3,4 They are a diverse and chemically complex family of compounds that can be divided into three major groups depending on the structure of the aglycone, which may be a steroid, a steroidal alkaloid, or a triterpenoid. These molecules have been proposed to contribute to plant defense.3 6 Saponins are also exploited as drugs and medicines and for a variety of other purposes.4 Despite the considerable commercial interest in this important group of natural products, little is known about their biosynthesis. This is due in part to the complexity of the molecules, and also to the lack of pathway intermediates for biochemical studies. 

The glycopeptide antibiotics are glycosylated secondary metabolites of bacteria and fungi that are s)mthesized by non-ribosomal peptide synthetases. The term glycopeptide antibiot-... 

Quantification of the Glycosylated Secondary Metabolites Through a Determination of the Glycosyl-Glucose (G-G). 

In terms of usage, due to its versatility and flexibility, HP-RPC techniques dominate the separation of secondary metabolites at the analytical, laboratory-scale, and preparative levels, since the majority of secondary metabolites possess some degree of hydrophobicity.18 19 Figure 3 shows the analysis of glycosylated flavonoids and other phenolic compounds using HP-RPC.20... 

Many of the naturally occurring secondary metabolites from bacteria and plants are glycosylated, mostly by 6-deoxyhexoses derived from dTDP-glucose (deoxythymidine 5 -diphospho glucose). 6-Deoxyhexose derivatives are present in a variety of antibiotics from actinomycetes, including macrolides, polyenes, and aminoglycosides, among others. 

Triterpenoids are a group of secondary metabolites widely distributed in nature. Their relatively complex cyclic carbon structures, based on six isoprene units, can be heavily substituted with different functional groups, which may be esterilied or glycosylated, for instance. As a result, over 20,000 different natural triterpenoids are known to humans. Among the most widely spread are pentacyclic triterpenoids (C30), which can be divided into several structural subgroups based on their skeleton. Many of these compounds show important pharmacological activities. Reported beneficial effects of various triterpenoids on human health indicate the nutritional importance of these compounds. 

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