GSN Evening Primrose Oil 500mg/100 pearls. The seed oil Evening Primrose GSN is a product rich in essential fatty acids such as oleic, linoleic, gamma-linolenic, palmitic and stearic. Each pearl contains 500 mg of Pure Oil Seeds Oenothera biennis (Evening Primrose), first cold pressed, rich in essential fatty acids and 1 mg of vitamin E in a natural base of gelatin. Pearls of evening primrose oil GSN quick disintegration, not contain any preservatives, colorings, flavorings, or allergens