I'd try hydrolyzing in 6N HCl.

I like to use an ampoule that I can seal; I freeze the solution (liquid nitrogen works well if you can get it) in the ampoule, pull a vacuum, close off the vacuum (but don't disconnect from the vacuum line). Allow to thaw, then freeze again and seal with a flame. This removes air that may oxidize the sample while heating. I heat at 100° C overnight and analyze the next day. I used this procedure in this paper: https://www.researchgate.net/publication/14525877_Phospholipase_D_inhibitors_from_a_Myrsine_species

Article Phospholipase D Inhibitors from a Myrsine Species

I agree with Jack but if sealing is inconvenient - Pyrex tubes with stopper works fine too on a heating block - I don't think you to cook overnight. 5-6 hours of heating should be enough to remove the glycoside linkage.

thank you so much for the answers

Dear Ms. Sujata

The attached information may be useful to you.

Best wishes.

@jACK SILVER Could you please make the method more elaborate .As in i want to set up the apparatus .

@Wangkheirakpam Sujata

I used ampules suchas these: http://wheaton.com/laboratory/ampules-vacules.html ; you should be able to get them from your dealer in India, Fisher, VWR, or Aadyanth Inc. 

The sample is placed in the ampule and the top is attached to a vacuum source (a water aspirator will work). I have a simple valve in the vacuum line so I can leave the vacuum running when I defrost the sample. The vacuum line was chosen to fit the top of the ampule. After following the air removal I described above, I used a hand torch to seal the ampule just below the vacuum line. Since the vacuum is turned on while sealing, the glass collapses on itself easily.

Jatinder Rana's method will work too, but I removed the air to improve the yield and reduce oxidation. I found I had a clear solution by taking the extra steps while I got a slightly brown solution when I didn't remove the air.

@JACK SILVER how did you manged freezing and defrosting  and why was it done i cant get the reason behind it .My lab is not so well equiped so I have to arrange the set p newly.

Acid or alkaline hydrolysis of saponin glycosides are exercised to deglycosolate the sugar moieties leaving the most part an intact aglycone. The aglycone and related glycosides are then separated and visualized on TLC) before and after hydrolysis to confirm the presence of different aglycones and to assign new compounds to their respective groups based on TLC migratory patterns. Acid hydrolysis is generally the preferred method to get sapogenin from crude extracts. Acid hydrolysis in anhydrous methanol has been reported to enable the highest recovery of sapogenins without producing artifacts. Alkaline hydrolysis (with 5% NaOH in anhydrous methanol) on the other hand, tends to produce partial hydrolysis.

thank you i know the principle as i am looking for the aglycone i have been trying with refluxing normally with sulfuric acid .As the compound is less i want ed to get a good method first . i have been haeting at 00 degree without vaccuum . i am just unaware of the freezing and defrosting in the method by JACK SILVER1

For natural product compounds, the method is very important for isolation of sapogenin (genin) and their aglycone.  A fast and simple method for the separation and purification and identification of triterpene saponins from Chenopodium quinoa Willd. We should  use both methods of basic hydrolysis and acid hydrolysis for the isolation of sugars and aglycones.

http://www.sciencedirect.com/science/article/pii/S0031942208001179

thank you so much for the informations