Evening Primrose Oil from Pure Encapsulations is extracted from the seeds of the evening primrose (Oenothera biennis). For generations, evening primrose oil has been prized by many because it contains up to 14% of the unsaturated fatty acid gamma-linolenic acid (GLA), which has immune-boosting and antioxidant properties. Pure Encapsulations' evening primrose oil is cold-pressed without the use of solvents. Like all Pure Encapsulations products, evening primrose oil is manufactured according to strict international standards. To ensure long-term, consistently high product quality, the entire process, from production to storage, is constantly monitored. Internal and external quality controls are implemented at every stage.