Treatment of microbial infections

Abstract

The present application relates to an anti-microbial system for use in the treatment of microbial infections or control of microbial contamination, which avoids the use of antibiotics. Such infections include mastitis, tuberculosis, cystic fibrosis and the contamination that may result from biofilm formation on medical devices.

1 . A microbiocidal composition comprising a reactive oxygen species or components capable of producing a reactive species, the composition being capable of delivering the reactive oxygen species to a level of at least 0.4 millimoles per litre, over a 24 hour period. 
     
     
         2 . A composition as claimed in  claim 1  capable of delivering the reactive oxygen species to a level of at least 0.5 millimoles per litre, over a 24 hour period. 
     
     
         3 . A composition as claimed in  claim 1  or  2  wherein the reactive oxygen species is produced by the reaction of a peroxidase, a substrate for the peroxidase and hydrogen peroxide. 
     
     
         4 . A composition as claimed in any preceding claim where the reactive oxygen species is selected from the group comprising hypothiocyanate (hypothiocyanite, SCNO − ), hypoiodate (IO − ) and hypochlorite (CLO − ). 
     
     
         5 . A composition as claimed in  claim 3  or  4  wherein the peroxidase enzyme is selected from the group comprising a lactoperoxidase, a chloroperoxidase, a bromoperoxidase and an iodooxidase. 
     
     
         6 . A composition as claimed in  claim 5  comprising a lactoperoxidase enzyme and further comprising iodide or thiocyanate ions. 
     
     
         7 . A composition as claimed in  claim 5  comprising a chloroperoxidase enzyme and further comprising chloride ion. 
     
     
         8 . A composition as claimed in any of  claims 3  to  7  where the source of hydrogen peroxide is a solution of the hydrogen peroxide. 
     
     
         9 . A composition as claimed in any preceding claim where the hydrogen peroxide is released by a hydrogen peroxide releasing compound selected from the group comprising percarbonates, citric acid and perhydrates, or by enzymatic methods. 
     
     
         10 . A composition as claimed in any of  claims 3  to  9  where the hydrogen peroxide is produced by an enzymatic reaction between a sugar and its appropriate oxidoreductase 
     
     
         11 . A composition as claimed in  claim 10  wherein the oxidoreductase is galactose oxidase and/or glucose oxidase. 
     
     
         12 . A composition as claimed in  claim 11  further comprising free monosaccharide sugar(s). 
     
     
         13 . A composition as claimed in any of  claims 3  to  12  further comprising a disaccharide sugar, and its corresponding glycoside hydrolase to produce a source of hydrogen peroxide. 
     
     
         14 . A composition as claimed in  claim 13  wherein the glycoside hydrolase is Beta-galactosidase, and the disaccharide sugar is lactose. 
     
     
         15 . A composition as claimed in any preceding claim wherein a glycoside hydrolase and/or an oxidoreductase is used to react with sugars present at the infection site. 
     
     
         16 . A composition as claimed in  claim 10  wherein the additional source of hydrogen peroxide is derived from the reaction of a polyol (sugar alcohol) with its relative oxidase enzyme. 
     
     
         17 . A composition as claimed in  claim 16  wherein the polyol is glycerol and its relative oxidase enzyme is glycerol oxidase, or wherein the polyol is mannitol and its relative oxidase enzyme is mannitol oxidase. 
     
     
         18 . A composition as claimed in any of  claims 2  to  17  wherein the hydrogen peroxide is produced from the enzymatic reaction of L-amino acids with L-amino acid oxidase or xanthine (or hypoxanthine) and xanthine oxidase. 
     
     
         19 . A composition as claimed in any preceding claim further comprising either hypoxanthine or xanthine or both. 
     
     
         20 . A composition as claimed in  claim 19  further comprising free amino acids. 
     
     
         21 . A composition claimed in any preceding claim additionally comprising lactoferrin, or a glucocorticoid. 
     
     
         22 . A composition claimed in  claim 21  wherein the glucocorticoid is prednisolone or prednisone. 
     
     
         23 . A composition as claimed in any preceding claim adapted for intramammary infusion or nebulisation, for use as an antimicrobial solution, emulsion or dried product, for use as an antimicrobial solution to be added to a poultice for a burn lesion to the skin, for use as an antimicrobial solution to be used as a nasal rinse, for use as an antimicrobial solution to be used as a surface cleaner. 
     
     
         24 . An intramammary infusion delivery device loaded with a composition as claimed in any preceding claim. 
     
     
         25 . A composition as claimed in any preceding claim where the solution is prepared as an emulsion, or dried product. 
     
     
         26 . A composition as claimed in any preceding claim wherein the compounds are adhered to the surface of a medical device. 
     
     
         27 . A composition as claimed in any preceeding claim where the components are adapted for delivery sequentially or cumulatively to the infection site. 
     
     
         28 . A composition as claimed in any preceeding claim where the components are allowed to react before addition to the infection site. 
     
     
         29 . A composition as claimed in any preceeding claim where the components are allowed react before addition to the infection site, and treated with catalase to remove excess hydrogen peroxide.