Grapefruit Seed Extract Dårligst Plant extracts No known benefits Grapefruit Seed Extract description Labelled as _Citrus paradisi_ (grapefruit) seed extract, this is often claimed as a natural preservative when added to cosmetics. However, research has demonstrated that it is not an ideal preservative agent, as it cannot protect against both the most common forms of growth - even in sealed, pump-style packaging. [1,2,3] Yes, citrus extracts can have preservative-like benefits, but they’re simply not strong enough to defend against from a broad range of substances necessary to properly preserve a skin care product.