I prepared crude saponins using the following protocol: heat 5g of plant extract in 30 ml of 20% methanol in 4 hrs in a water bath to reduce volume to 15 mls. I added 20 mls diethyl ether to separate organic portion from the aqueous. The organic portion was discarded. I added 15ml butanol to the methanolic fraction to obtain 30ml methanol/n-butanol fraction. The latter was washed with 50 ml 5% Nacl solution and the the aqueous fraction discarded. The methanol/n-butanol fraction obtained was washed for the second time with another 50ml of 5% Nacl and there was no separation into methanol/n-butanol fraction and aqueous fraction. I therefore evaporated both mixture of methanol/n-butanol fraction and aqueous solution to dryness to obtain a crystalline soapy extract. Is my protocol right? What have done wrong here? somebody help me!
I work with ginseng saponins and ultrasonication based extraction with 100% methanol works the best in my case, even though 70% methanolic solutions are just as fine.You may try extraction using a particular methanolic solution apt for you. Try partitioning with di-ethyl ether using an aqueous phase rather than the methanolic solution. After removal of organic layer, you may try water saturated butanol for partitioning. The butanolic extract may be evaporated in vaccuum to obtain a crude saponin mixture.
Check this thread for possible answers to your question. In addition there are several threads on the subject of saponins which can be accessed by double clicking on saponins topic in your thread.
https://www.researchgate.net/post/how_could_be_assayed_the_total_saponins_in_a_plant_extract
I think You have to avoid the use of 5% NaCl and there should be 75% methanol or 80% ethanol with plant extract and keep it in shaking machine at least for 72 hours, at room temperature or you may keep it in cold room (2-8 degree C.). and then Filter with What-man filter paper and then evaporate with rotary evaporator machine.
Tee Lucky, I think the method you have used is still ok because it is similar to the AOAC method of 1975. However, considering the method suggested by Kebede will also yield a better result. but you should also bear in mind the method of analysis.
- Badges
- Science topic
- Similar topics
- Biological Science
- Botany
- Pharmaceutical Botany
- Plant Extracts