Gamma-Linolenic acid is an isomer of α-linolenic acid, which is a polyunsaturated n−3 (omega-3) fatty acid, found in rapeseed canola oil, soybeans, walnuts, flax seed (linseed oil), perilla, chia, and hemp seed. GLA was first isolated from the seed oil of evening primrose. This herbal plant was grown by Native Americans to treat swelling in the body. In the 17th century, it was introduced to Europe and became a popular folk remedy, earning the name "king's cure-all." In 1919, Heiduschka and Lüft extracted the oil from evening primrose seeds and described an unusual linolenic acid, which they name γ-. Later, the exact
Narva Oil Plant from the power plants and the separate subsidiary of Eesti Energia was established. The retorting plant consists of two modified Galoter type solid heat carrier retorts (Enefit retort)—both processing 125 tonnes per hour of oil shale. Main products are fuel grade shale oil, raw material for bitumen and antiseptics. The designed annual capacity of the plant is 220,000 tons of shale oil and 60 million cubic meters of retort gas. In May 2009, Eesti Energia announced that it plans to build a new shale oil plant adjacent to the existing plant with processing capacity of 2.26 million tonnes of oil