Californian supplement manufacturer Source Naturals is promoting an improved version of its phosphatidyl serine (PS) soft gels, with the claim that the product contains the most shelf-stable PS available.
Source Naturals' Phosphatidyl Serine Complex soft gels contain Leci-PS, produced by German chemicals firm Degussa.
PS is thought to reverse the effects of age-related cognitive decline and loss of memory, and has also been shown to reduce stress and depression. The FDA has approved two health claims for the function of PS in brain health. The chemical is found naturally in soy beans, green leafy vegetables, rice and certain meat products.
Degussa recently reported that it had investigated the activity of PS in soft gels and had identified key problems that cause variation in the quality of the ingredient when formulated in soft gels.
Tests found that an enzyme used in the manufacture of PS must be eliminated prior to encapsulation because it reacts with glycerol (in the gelatin), causing a degradation of PS. They also showed that moisture from the gelatin shell could cause a further loss of content.
A new, patent-pending Leci-PS 20V blend developed by the German group, and used in Source Naturals soft gels, is entirely free of residual enzyme activity and is also said to be shelf-stable, unlike many other PS formulas.
Source Naturals cites a clinical trial by Crook (1998) showing that three months of supplementation with soy-derived PS has comparable effects on memory and cognition to bovine-derived PS.