Spirostanol monodesmosides

Antiyeast spirostanol-monodesmosides The deterioration of cooked foods is known to be caused by yeasts. 

The vast majority of structurally elucidated solanaceous saponins are spirostanol monodesmosides, characterized by one carbohydrate chain comprising usually 2-5 monosaccharide units which is attached glycosidically to the hydroxyl at C-3P of the aglycone, thus forming an acetal linkage. However, in case of several 6a-hydroxylated... 

The selective hydrolysis of 26-O-glycoside linkage of the 3, 26-O-bisdesmosides which is followed by sponteneous cyclization of the side chain to form a spirostanol-3-O-monodesmoside, has been observed for homogenates of some plants which contain both furostanol-3, 26-O-bisdesmosides and corresponding spirostanol-3-O-monodesmosides. However, isolation and characterization of an enzyme which is responsible for this novel activity, has not been reported until recently. 

Costus speciosus (Zingiberaceae) grows wild in Southeast and South Asia. From the rhizomes, a number of spirostanol-3-O-monodesmosides of diosgenin and the corresponding fiirostanol-3,26-0-bisdemosides have been isolated as shown in Fig. 5 [10]. 

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