Disclosed is a method for preparing a fine powder of a polymannan extract comprising the steps of: weighing a specified quantity of a freeze-dried aloe powder, wherein the quantity is corrected for a moisture content dissolving the freeze-dried aloe powder in deionised water to form a solution adding a first volume of an organic solvent to the solution to form a first mixture wherein the organic solvent to the deionised water ratio is at least 2.5:1 allowing the first mixture to settle for at least 8 hours withdrawing a specified volume of a supernatant solution from the first mixture and adding a second volume of the organic solvent to the specified volume of the supernatant solution to form a second mixture centrifuging the second mixture observing for a presence of a precipitate in the second mixture adding a third volume of the organic solvent to the first mixture if any precipitate is observed in the second mixture decanting the supernatant of the first mixture by siphoning, wherein the decantation is done only if no precipitate is observed in the second mixture filtering the precipitate from the first mixture by using a filter paper and a suction funnel under vacuum recovering the powder of the polymannan extract from the suction funnel by scraping placing the powder of the polymannan extract in a capped lyophilisation flask in a freezer for at least 8 hours lyophilising the frozen powder of the polymannan extract in a lyophiliser and grinding the lyophilised powder of the polymannan extract in a grinder to a desired texture.
