PURE 3R-3'R STEREOISOMER OF ZEAXANTHIN FOR TREATING MACULAR DEGENERATION IN HUMANS

摘要

Methods and formulations are disclosed for makingand purifying the 3R-3'R stereoisomer of zeaxanthin as asole detectable isomer, in any desired quantity, for useas a drug or vitamin by humans. Zeaxanthin, a yellowishpigment which is naturally present in macular cells inthe center of the human retina, absorbs blue and near-ultraviolet light radiation, thereby protecting retinalcells against phototoxic damage. Zeaxanthin preparationswhich contain only the desired 3R-3'R stereoisomer can beproduced by a strain of Flavobacterium mul tivorum cells(ATCC accession number 55238). These cells (and othercells transformed with their zeaxanthin-producing genes)do not create any detectable quantities of the undesiredS-S or S-R isomers of zeaxanthin, and they do notsynthesize significant quantities of other carotenoidswhich might compete against zeaxanthin for alimentaryuptake after oral ingestion. After synthesis usingmicrobial fermentation, the zeaxanthin can beconcentrated to about 5 to 20% by simple and inexpensivesteps such as solvent extraction. It can also be purifiedto much higher levels by other methods, if desired. Thepure R-R isomer can be taken orally, either as atherapeutic drug by patients suffering from maculardegeneration, or as a vitamin or nutritional supplementby anyone who wants to reduce his or her risk ofsuffering from age-related macular degeneration, which iswidespread among people over the age of about 50 or 60.Extraction solvents, stabilizing agents, and convenientformulations for oral ingestion (such as mixed withvegetable oil and encapsulated, or used as a margarine orfood additive) are also disclosed.