Methods for enzymatic decolorization of chlorophyll

Abstract

The invention provides the invention provides compositions and methods for the enzymatic treatment (“bleaching” or “de-colorizing”) of chlorophyll-comprising compositions, e.g., algae preparations, chlorophyll-containing or chlorophyll-contaminated feeds, foods or oils, for example, vegetable oils, including oils processed from oilseeds, such as canola (rapeseed) oil or soybean oil, or oil fruits, such as palm oil. In one aspect, the invention provides methods using a chlorophyllase enzyme for the enzymatic hydrolysis of chlorophyll in an algae, an animal (e.g., a fish) or plant preparation, a food or an oil. In one aspect, the chlorophyllase is immobilized onto a silica. The invention also provides compositions of manufacture and detergents.

What is claimed is: 
     
         1 . A method of enzymatic treatment comprising:
 a) providing at least one polypeptide according to the polypeptide of SEQ ID NO: 22 or the polypeptide encoded by the nucleic acid sequence of SEQ ID NO: 21 and having a chlorophyllase activity   b) de-coloring a pheophytin-containing composition under conditions wherein the at least one polypeptide catalyzes hydrolysis of pheophytin to generate pheophorbide and a phytol; and   c) separating said pheophorbide and phytol.   
     
     
         2 . The method of  claim 1 , wherein the polypeptide is immobilized on: an array, a cell, a metal, a resin, a polymer, a ceramic, a glass, a microelectrode, a graphitic particle, a bead, a gel, a plate, a capillary tube, an inorganic support or organic support, and optionally the support comprises: an alumina, celite, Dowex-1-chloride, glass beads, silica, silica gel, alginate hydrogel, or alginate bead. 
     
     
         3 . The method of  claim 1 , wherein the pheophytin containing composition:
 (a) is derived from a plant, an animal or an algae, or a mixture thereof,   (b) comprises a plant material, plant oil or plant extract,   (c) comprises a vegetable oil or a seed oil,   (d) comprises a palm oil or a canola oil,   (e) comprises a crude oil or a refined oil,   (f) comprises an undiluted crude oil preparation, or   (g) comprises an algae preparation.   
     
     
         4 . The method of  claim 1 , wherein at least one step of the treatment is performed in a reaction vessel, and optionally the reaction vessel comprises a gravitational gum separation device or a holding tank. 
     
     
         5 . The method of  claim 1 , wherein at least one step of the treatment is performed in a cell extract or in a whole cell. 
     
     
         6 . The method of  claim 1 , wherein the treatment further comprises modifying pH to promote aqueous separation of a pheophorbide. 
     
     
         7 . The method of  claim 1 , wherein the treatment is combined with a caustic neutralization step. 
     
     
         8 . The method of  claim 1 , wherein polypeptide is used with a phospholipase and optionally the phospholipase is a phospholipase C. 
     
     
         9 . The method of  claim 1 , wherein the treatment is included in a degumming process. 
     
     
         10 . The method of  claim 1 , wherein the treatment further comprises the removal of residual chlorophyll or pheophytin; pesticides; or a polycyclic aromatic hydrocarbons. 
     
     
         11 . The method of  claim 1 , wherein the enzymatic treatment of a pheophtin-containing composition is combined with a degumming process and a caustic neutralization step.