Antimicrobial compositions

Inventors

Patton, Thomas • Brennan, James • Barrett, John Reginald • STAPLES, Ian

Assignees

Matoke Holdings Ltd

Abstract

Storage-stable compositions for generating antimicrobial activity are described. The compositions comprise an enzyme that is able to convert a substrate to release hydrogen peroxide, and an unrefined natural substance, such as a honey, that includes a substrate for the enzyme. In certain embodiments, the enzyme is a purified enzyme. In other embodiments, the substrate lacks catalase activity, and the enzyme is additional to any enzyme activity able to convert the substrate to release hydrogen peroxide that may be present in the unrefined natural substance. The storage-stable compositions do not include sufficient free water to allow the enzyme to convert the substrate. Use of the compositions to treat microbial infections and wounds is described, as well as methods for their production.

Core Innovation

The disclosure relates to sterile, storage-stable antimicrobial compositions that generate antimicrobial activity by exogenous addition of a hydrogen-peroxide-producing enzyme, including glucose oxidase, to an unrefined natural substrate that includes D-glucose. Key stability is achieved by preventing hydrogen peroxide generation during storage, so the enzyme does not convert the D-glucose while the composition is stored. At use, hydrogen peroxide generation occurs after dilution and conversion under conditions that permit the glucose oxidase to act.

The composition limits free water and/or sets water activity so the glucose oxidase does not produce hydrogen peroxide during storage, while still allowing antimicrobial activity after dilution at use. Variability reduction is emphasized by using substrates lacking catalase activity and/or lacking substrate-conversion activity, including pasteurized honey to inactivate catalase and endogenous glucose oxidase. The disclosure also emphasizes excluding ozonized honey or ozonized oil and avoiding added peroxidase, thereby keeping the composition substantially free of hydrogen peroxide.

The document further supports antimicrobial activity and includes rationales for wound-healing properties, including antimicrobial and wound-healing uses. Delivery and form factors are described, including dressings, solutions, and kits, and sterility is described as achievable by gamma irradiation. Extensive experimental support is described, including well-diffusion assays with phenol-equivalent potency control, stability after storage and irradiation, MIC/MBC and time-kill data for topical formulations, antiviral activity, and examples addressing wound infection outcomes and device-related colonization.

Claims Coverage

The provided independent claim is clm-00001, which recites a sterile storage-stable composition for generating antimicrobial activity with a hydrogen-peroxide-producing system constrained by water conditions and multiple exclusions. The claim includes several main inventive features, and the dependent claims further refine these features, including specifying honey as the sugar substance, pasteurization of the honey, powder form, irradiation sterilization, and quantitative glucose oxidase content.

Across the independent claim, the invention is defined by combining glucose oxidase with a sugar substance that includes D-glucose but lacks catalase and glucose oxidase activity, while enforcing storage stability by limiting free water or setting aw between 0.47 and 0.7, and excluding ozonized honey/oil, hydrogen peroxide, and any added peroxidase.

Stated Advantages

Documented Applications