Dear Sudheer

I will suggest you to use a desiccator instead of these chemicals for storing the extract. If possible, first spray dry the extract and get it in a powder form. Otherwise also you can keep it as such. Just try to remove as much solvent as you can by keeping it on a water bath. Concentrate it sufficiently and store in a normal desiccator with any of the following desiccant chemicals (this list is not limited, many more are available):

1. silica gel (the beads in little packets, you might have seen very often)

2. sodium hydroxide

3. calcium chloride (anhydrous)

The desiccant will need to be replaced after it has absorbed all of the water that it can hold. Some chemicals will liquefy when this occurs so that you will know they need to be replaced (e.g., sodium hydroxide). Otherwise, you'll just need to switch out the desiccant when it starts to lose its effectiveness.

If you store properly in this way, it will never catch fungus. This is just a simple in-house method. Try and see the result.

Regards

Put the solid extract in the vial and at the top of the extract add 5ml ethanol that will prevent the fungus formation.

The second way to stop fungus formation on aqueous plant extract is dry the extract at low temperature in oven for 2-3 days.

Maintain ph 2.8-3.0 with phosphoric Acid to prevent formation of fungus

Centrifuge the extract and then put it in a waterbath at 50C for 30 minutes. Cool and store in refrigerator. The pasteurization processes can be repeated second time if needed.

If the extract is still in water put some benzene 5-10 ml and keep in freeze. If the extract is viscous completely dry it under vacuum and again put some benzene and distill completely under vacuum until free of water. Keep in Desiccator containing Calcium chloride fused

Add Chloroform 2ml per 1000 ml Water extract solution and keep tight by aluminum foil. This is approved method as per pharmacoepia

@ Pushpinder kaur : Just read Indian Pharmacoepia 1966. They give the formula to prepare chloroform water 2.5 ml in 1000 ml for deatail read B.Pharm Firs year Practical book here page no 4

http://books.google.co.in/books?id=nxkDvaGboEIC&pg=PA3&lpg=PA3&dq=chloroform+water+ip&source=bl&ots=9j7WXMtR9z&sig=pljk8m06fD2-mPlAvptasjYOG3s&hl=en&sa=X&ei=ArbRUJjpKo3IrQeny4DIDA&ved=0CEgQ6AEwBA#v=onepage&q=chloroform%20water%20ip&f=false

when we use in this conc chloroform it is easily miscible and prevent from fungus grow

Dear Sudheer

I will suggest you to use a desiccator instead of these chemicals for storing the extract. If possible, first spray dry the extract and get it in a powder form. Otherwise also you can keep it as such. Just try to remove as much solvent as you can by keeping it on a water bath. Concentrate it sufficiently and store in a normal desiccator with any of the following desiccant chemicals (this list is not limited, many more are available):

1. silica gel (the beads in little packets, you might have seen very often)

2. sodium hydroxide

3. calcium chloride (anhydrous)

The desiccant will need to be replaced after it has absorbed all of the water that it can hold. Some chemicals will liquefy when this occurs so that you will know they need to be replaced (e.g., sodium hydroxide). Otherwise, you'll just need to switch out the desiccant when it starts to lose its effectiveness.

If you store properly in this way, it will never catch fungus. This is just a simple in-house method. Try and see the result.

Regards

The another good technique is kept in deep freezer. No fungus is grow