Production of beta-glucans and mannans
Disclosed are methods for producing yeast β-glucan and mannan preparations. The methods employ an autolysis process, followed by enzymatic treatment with one or more of a protease, glucanase or lipase. The preparations produced may be used in food supplements, pharmaceuticals, cosmetics, animal feeds, and neutraceuticals.
1. A method for processing yeast cells comprising:
(a) autolyzing the yeast cells at a temperature of 50° C. to 65° C. to release yeast cell walls;
(b) incubating the cell walls with an exogenous protease at a pH of 9 to 10;
(c) incubating the protease-treated cell walls of step (b) with an enzyme comprising at least one of an amylase, lipase and a combination thereof;
(d) separating the enzyme-treated cell walls of step (c) into a glucan-enriched component and a mannan-enriched component; and
(e) separately retaining said glucan-enriched component and said mannan-enriched component;
wherein said glucan-enriched component of step (e) can be added to an animal feed or to a product selected from a food supplement, pharmaceutical, cosmetic and neutraceutical.
2. The method of claim 1 , wherein the yeast cells comprise brewer's yeast cells.
3. The method of claim 1 , wherein step (c) is carried out at a pH of 4 to 6.
4. The method of claim 1 , further comprising adding the glucan-enriched component of step (e) to a product selected from a food supplement, pharmaceutical, cosmetic and neutraceutical.
5. The method of claim 1 , further comprising
(f) ultrafiltering the mannan-enriched component of step (e) to form a filtrate and a retentate.
6. The method of claim 1 , wherein the retentate comprises mannans, and wherein at least 85% (w/w) of the mannans have a molecular weight of at least 10,000 Da.
7. The method of claim 5 , further comprising adding the filtrate of step (f) to a product selected from a food supplement, pharmaceutical, cosmetic and neutraceutical.